wow-mpq 0.6.4

//! MPQ archive handling
//!
//! This module provides the main Archive type for reading MPQ files.
//! It supports:
//! - All MPQ versions (v1-v4)
//! - File extraction with decompression
//! - Sector CRC validation
//! - Encryption/decryption
//! - Multi-sector and single-unit files

use crate::{
    Error, Result,
    builder::ArchiveBuilder,
    compression,
    crypto::{decrypt_block, decrypt_dword, hash_string, hash_type},
    header::{self, MpqHeader, UserDataHeader},
    special_files,
    tables::{BetTable, BlockTable, HashTable, HetTable, HiBlockTable},
};
use byteorder::{LittleEndian, ReadBytesExt};
use std::fs::File;
use std::io::{BufReader, Read, Seek, SeekFrom};
use std::path::{Path, PathBuf};

/// Detailed information about an MPQ archive
#[derive(Debug, Clone)]
pub struct ArchiveInfo {
    /// Path to the archive file
    pub path: PathBuf,
    /// Total file size in bytes
    pub file_size: u64,
    /// Archive offset (if MPQ data starts after user data)
    pub archive_offset: u64,
    /// MPQ format version
    pub format_version: header::FormatVersion,
    /// Number of files in the archive
    pub file_count: usize,
    /// Maximum file capacity (hash table size)
    pub max_file_count: u32,
    /// Sector size in bytes
    pub sector_size: usize,
    /// Archive is encrypted
    pub is_encrypted: bool,
    /// Archive has digital signature
    pub has_signature: bool,
    /// Signature status (if applicable)
    pub signature_status: SignatureStatus,
    /// Hash table information
    pub hash_table_info: TableInfo,
    /// Block table information
    pub block_table_info: TableInfo,
    /// HET table information (v3+)
    pub het_table_info: Option<TableInfo>,
    /// BET table information (v3+)
    pub bet_table_info: Option<TableInfo>,
    /// Hi-block table information (v2+)
    pub hi_block_table_info: Option<TableInfo>,
    /// Has (attributes) file
    pub has_attributes: bool,
    /// Has (listfile) file
    pub has_listfile: bool,
    /// User data information
    pub user_data_info: Option<UserDataInfo>,
    /// MD5 checksums status (v4)
    pub md5_status: Option<Md5Status>,
}

/// Information about a table in the archive
#[derive(Debug, Clone)]
pub struct TableInfo {
    /// Table size in entries (None if table failed to load)
    pub size: Option<u32>,
    /// Table offset in archive
    pub offset: u64,
    /// Compressed size (if applicable)
    pub compressed_size: Option<u64>,
    /// Whether the table failed to load
    pub failed_to_load: bool,
}

/// User data information
#[derive(Debug, Clone)]
pub struct UserDataInfo {
    /// User data header size
    pub header_size: u32,
    /// User data size
    pub data_size: u32,
}

/// Digital signature status
#[derive(Debug, Clone, PartialEq)]
pub enum SignatureStatus {
    /// No signature present
    None,
    /// Weak signature present and valid
    WeakValid,
    /// Weak signature present but invalid
    WeakInvalid,
    /// Strong signature present and valid
    StrongValid,
    /// Strong signature present but invalid
    StrongInvalid,
    /// Strong signature present but no public key available
    StrongNoKey,
}

/// MD5 checksum verification status for v4 archives
#[derive(Debug, Clone)]
pub struct Md5Status {
    /// Hash table MD5 valid
    pub hash_table_valid: bool,
    /// Block table MD5 valid
    pub block_table_valid: bool,
    /// Hi-block table MD5 valid
    pub hi_block_table_valid: bool,
    /// HET table MD5 valid
    pub het_table_valid: bool,
    /// BET table MD5 valid
    pub bet_table_valid: bool,
    /// MPQ header MD5 valid
    pub header_valid: bool,
}

/// Options for opening MPQ archives
///
/// This struct provides configuration options for how MPQ archives are opened
/// and initialized. It follows the builder pattern for easy configuration.
///
/// # Examples
///
/// ```no_run
/// use wow_mpq::{Archive, OpenOptions};
///
/// // Open with default options
/// let archive = Archive::open("data.mpq")?;
///
/// // Open with custom options
/// let archive = OpenOptions::new()
///     .load_tables(false)  // Defer table loading for faster startup
///     .open("data.mpq")?;
/// # Ok::<(), wow_mpq::Error>(())
/// ```
#[derive(Debug, Clone)]
pub struct OpenOptions {
    /// Whether to load and parse all tables immediately when opening the archive.
    ///
    /// When `true` (default), all tables (hash, block, HET/BET) are loaded and
    /// validated during archive opening. This provides immediate error detection
    /// but slower startup for large archives.
    ///
    /// When `false`, tables are loaded on-demand when first accessed. This
    /// provides faster startup but may defer error detection.
    pub load_tables: bool,

    /// MPQ format version to use when creating new archives.
    ///
    /// This field is only used when creating new archives via `create()`.
    /// If `None`, defaults to MPQ version 1 for maximum compatibility.
    version: Option<crate::header::FormatVersion>,
}

impl OpenOptions {
    /// Create new default options
    ///
    /// Returns an `OpenOptions` instance with default settings:
    /// - `load_tables = true` (immediate table loading)
    /// - `version = None` (defaults to MPQ v1 for new archives)
    pub fn new() -> Self {
        Self {
            load_tables: true,
            version: None,
        }
    }

    /// Set whether to load tables immediately when opening
    ///
    /// # Parameters
    /// - `load`: If `true`, tables are loaded immediately during open.
    ///   If `false`, tables are loaded on first access.
    ///
    /// # Returns
    /// Self for method chaining
    pub fn load_tables(mut self, load: bool) -> Self {
        self.load_tables = load;
        self
    }

    /// Set the MPQ version for new archives
    ///
    /// This setting only affects archives created with `create()`, not
    /// archives opened with `open()`.
    ///
    /// # Parameters
    /// - `version`: The MPQ format version to use (V1, V2, V3, or V4)
    ///
    /// # Returns
    /// Self for method chaining
    pub fn version(mut self, version: crate::header::FormatVersion) -> Self {
        self.version = Some(version);
        self
    }

    /// Open an existing MPQ archive with these options
    ///
    /// # Parameters
    /// - `path`: Path to the MPQ archive file
    ///
    /// # Returns
    /// `Ok(Archive)` on success, `Err(Error)` on failure
    ///
    /// # Errors
    /// - `Error::Io` if the file cannot be opened
    /// - `Error::InvalidFormat` if the file is not a valid MPQ archive
    /// - `Error::Corruption` if table validation fails (when `load_tables = true`)
    pub fn open<P: AsRef<Path>>(self, path: P) -> Result<Archive> {
        Archive::open_with_options(path, self)
    }

    /// Create a new empty MPQ archive with these options
    ///
    /// Creates a new MPQ archive file with the specified format version.
    /// The archive will be empty but properly formatted.
    ///
    /// # Parameters
    /// - `path`: Path where the new archive should be created
    ///
    /// # Returns
    /// `Ok(Archive)` on success, `Err(Error)` on failure
    ///
    /// # Errors
    /// - `Error::Io` if the file cannot be created
    /// - `Error::InvalidFormat` if archive creation fails
    pub fn create<P: AsRef<Path>>(self, path: P) -> Result<Archive> {
        let path = path.as_ref();

        // Create an empty archive with the specified version
        let builder =
            ArchiveBuilder::new().version(self.version.unwrap_or(crate::header::FormatVersion::V1));

        // Build the empty archive
        builder.build(path)?;

        // Open the newly created archive
        Self::new().load_tables(self.load_tables).open(path)
    }
}

impl Default for OpenOptions {
    fn default() -> Self {
        Self::new()
    }
}

/// An MPQ archive
#[derive(Debug)]
pub struct Archive {
    /// Path to the archive file
    path: PathBuf,
    /// Archive file reader
    reader: BufReader<File>,
    /// Offset where the MPQ data starts in the file
    archive_offset: u64,
    /// Optional user data header
    user_data: Option<UserDataHeader>,
    /// MPQ header
    header: MpqHeader,
    /// Hash table (optional, loaded on demand)
    hash_table: Option<HashTable>,
    /// Block table (optional, loaded on demand)
    block_table: Option<BlockTable>,
    /// Hi-block table for v2+ archives (optional)
    hi_block_table: Option<HiBlockTable>,
    /// HET table for v3+ archives
    het_table: Option<HetTable>,
    /// BET table for v3+ archives
    bet_table: Option<BetTable>,
    /// File attributes from (attributes) file
    attributes: Option<special_files::Attributes>,
}

impl Archive {
    /// Open an existing MPQ archive
    pub fn open<P: AsRef<Path>>(path: P) -> Result<Self> {
        Self::open_with_options(path, OpenOptions::default())
    }

    /// Open an archive with specific options
    pub fn open_with_options<P: AsRef<Path>>(path: P, options: OpenOptions) -> Result<Self> {
        let path = path.as_ref().to_path_buf();
        let file = File::open(&path)?;
        let mut reader = BufReader::new(file);

        // Find and read the MPQ header
        let (archive_offset, user_data, header) = header::find_header(&mut reader)?;

        let mut archive = Archive {
            path,
            reader,
            archive_offset,
            user_data,
            header,
            hash_table: None,
            block_table: None,
            hi_block_table: None,
            bet_table: None,
            het_table: None,
            attributes: None,
        };

        // Load tables if requested
        if options.load_tables {
            archive.load_tables()?;
        }

        Ok(archive)
    }

    /// Load hash and block tables
    pub fn load_tables(&mut self) -> Result<()> {
        log::debug!(
            "Loading tables for archive version {:?}",
            self.header.format_version
        );

        // For v3+ archives, check for HET/BET tables first
        if self.header.format_version >= header::FormatVersion::V3 {
            // Try to load HET table
            if let Some(het_pos) = self.header.het_table_pos
                && het_pos != 0
            {
                let mut het_size = self
                    .header
                    .v4_data
                    .as_ref()
                    .map(|v4| v4.het_table_size_64)
                    .unwrap_or(0);

                // For V3 without V4 data, we need to determine the size
                if het_size == 0 && self.header.format_version == header::FormatVersion::V3 {
                    log::debug!("V3 archive without V4 data, reading HET table size from header");
                    // Try to read the table size from the HET header
                    match self.read_het_table_size(het_pos) {
                        Ok(size) => {
                            log::debug!("Determined HET table size: 0x{size:X}");
                            het_size = size;
                        }
                        Err(e) => {
                            log::warn!("Failed to determine HET table size: {e}");
                        }
                    }
                }

                if het_size > 0 {
                    log::debug!("Loading HET table from offset 0x{het_pos:X}, size 0x{het_size:X}");

                    // HET table key is based on table name
                    let key = hash_string("(hash table)", hash_type::FILE_KEY);

                    match HetTable::read(
                        &mut self.reader,
                        self.archive_offset + het_pos,
                        het_size,
                        key,
                    ) {
                        Ok(het) => {
                            let file_count = het.header.max_file_count;
                            log::info!("Loaded HET table with {file_count} max files");
                            self.het_table = Some(het);
                        }
                        Err(e) => {
                            log::warn!("Failed to load HET table: {e}");
                        }
                    }
                }
            }

            // Try to load BET table
            if let Some(bet_pos) = self.header.bet_table_pos
                && bet_pos != 0
            {
                let mut bet_size = self
                    .header
                    .v4_data
                    .as_ref()
                    .map(|v4| v4.bet_table_size_64)
                    .unwrap_or(0);

                // For V3 without V4 data, we need to determine the size
                if bet_size == 0 && self.header.format_version == header::FormatVersion::V3 {
                    log::debug!("V3 archive without V4 data, reading BET table size from header");
                    // Try to read the table size from the BET header
                    match self.read_bet_table_size(bet_pos) {
                        Ok(size) => {
                            log::debug!("Determined BET table size: 0x{size:X}");
                            bet_size = size;
                        }
                        Err(e) => {
                            log::warn!("Failed to determine BET table size: {e}");
                        }
                    }
                }

                if bet_size > 0 {
                    log::debug!("Loading BET table from offset 0x{bet_pos:X}, size 0x{bet_size:X}");

                    // First, check if the BET offset actually points to a HET table
                    // This is a known issue in some MoP update archives
                    self.reader
                        .seek(SeekFrom::Start(self.archive_offset + bet_pos))?;
                    let mut sig_buf = [0u8; 4];
                    self.reader.read_exact(&mut sig_buf)?;

                    if &sig_buf == b"HET\x1A" {
                        log::error!(
                            "BET offset points to HET table! This archive has swapped table offsets."
                        );
                        log::warn!(
                            "Skipping BET table loading for this archive due to invalid offset."
                        );
                    } else {
                        // Reset position and proceed with normal BET loading
                        self.reader
                            .seek(SeekFrom::Start(self.archive_offset + bet_pos))?;

                        // BET table key is based on table name
                        let key = hash_string("(block table)", hash_type::FILE_KEY);

                        match BetTable::read(
                            &mut self.reader,
                            self.archive_offset + bet_pos,
                            bet_size,
                            key,
                        ) {
                            Ok(bet) => {
                                let file_count = bet.header.file_count;
                                log::info!("Loaded BET table with {file_count} files");
                                self.bet_table = Some(bet);
                            }
                            Err(e) => {
                                log::warn!("Failed to load BET table: {e}");
                            }
                        }
                    }
                }
            }
        }

        // Check if we have valid HET/BET tables with actual entries
        let _has_valid_het_bet = match (&self.het_table, &self.bet_table) {
            (Some(het), Some(bet)) => {
                // Tables are valid if they have entries
                het.header.max_file_count > 0 && bet.header.file_count > 0
            }
            _ => false,
        };

        // Always try to load classic tables if they exist (for compatibility)
        // Only skip them if the archive appears to be truncated/corrupted
        if self.header.hash_table_size > 0 {
            // Load hash table
            let hash_table_offset = self.archive_offset + self.header.get_hash_table_pos();
            let uncompressed_size = self.header.hash_table_size as usize * 16; // Each hash entry is 16 bytes

            // For V4 archives, we have explicit compressed size info
            if let Some(v4_data) = &self.header.v4_data {
                // Validate V4 sizes are reasonable (not corrupted)
                let file_size = self.reader.get_ref().metadata()?.len();
                let v4_size_valid = v4_data.hash_table_size_64 > 0
                    && v4_data.hash_table_size_64 < file_size
                    && v4_data.hash_table_size_64 < (uncompressed_size as u64 * 2); // Compressed shouldn't be much larger

                if v4_size_valid {
                    // Use compressed size for V4
                    let compressed_size = v4_data.hash_table_size_64;

                    log::debug!(
                        "Loading hash table from 0x{hash_table_offset:X}, compressed size: {compressed_size} bytes, uncompressed size: {uncompressed_size} bytes"
                    );

                    // Check if it would extend beyond file
                    let file_size = self.reader.get_ref().metadata()?.len();
                    if hash_table_offset + compressed_size > file_size {
                        log::warn!("Hash table extends beyond file, skipping");
                    } else {
                        // Read potentially compressed table
                        match self.read_compressed_table(
                            hash_table_offset,
                            compressed_size,
                            uncompressed_size,
                        ) {
                            Ok(table_data) => {
                                // Parse the hash table from the decompressed data
                                match HashTable::from_bytes(
                                    &table_data,
                                    self.header.hash_table_size,
                                ) {
                                    Ok(hash_table) => {
                                        self.hash_table = Some(hash_table);
                                    }
                                    Err(e) => {
                                        log::warn!("Failed to parse hash table: {e}");
                                    }
                                }
                            }
                            Err(e) => {
                                log::warn!("Failed to decompress hash table: {e}");
                            }
                        }
                    }
                } else {
                    // V4 sizes are invalid, fall back to V3-style detection
                    log::warn!(
                        "V4 archive has invalid compressed size ({}), using heuristic detection",
                        v4_data.hash_table_size_64
                    );
                    // Fall through to V3-style detection below
                }
            }

            // If we don't have valid V4 data or V4 size was invalid, use heuristic
            if self.hash_table.is_none() {
                // For V3 and earlier, or V4 with invalid sizes, we need to detect if tables are compressed
                // by checking the available space between tables
                let block_table_offset = self.archive_offset + self.header.get_block_table_pos();
                let available_space = if block_table_offset > hash_table_offset {
                    (block_table_offset - hash_table_offset) as usize
                } else {
                    // If block table comes before hash table, calculate differently
                    let file_size = self.reader.get_ref().metadata()?.len();
                    (file_size - hash_table_offset) as usize
                };

                if available_space < uncompressed_size {
                    // Table appears to be compressed
                    log::debug!(
                        "V3 hash table appears compressed: available space {available_space} < expected size {uncompressed_size}"
                    );

                    // Try to read as compressed
                    match self.read_compressed_table(
                        hash_table_offset,
                        available_space as u64,
                        uncompressed_size,
                    ) {
                        Ok(table_data) => {
                            match HashTable::from_bytes(&table_data, self.header.hash_table_size) {
                                Ok(hash_table) => {
                                    self.hash_table = Some(hash_table);
                                }
                                Err(e) => {
                                    log::warn!("Failed to parse hash table: {e}");
                                }
                            }
                        }
                        Err(e) => {
                            log::warn!("Failed to decompress hash table: {e}");
                            // Try to read as truncated uncompressed table
                            // Calculate how many entries we can fit in available space
                            let entries_that_fit = available_space / 16; // 16 bytes per entry
                            // Round down to nearest power of 2 for hash table
                            let mut pow2_entries = 1u32;
                            while pow2_entries * 2 <= entries_that_fit as u32 {
                                pow2_entries *= 2;
                            }
                            if pow2_entries > 0 {
                                log::warn!(
                                    "Trying to read truncated hash table with {} entries (originally {})",
                                    pow2_entries,
                                    self.header.hash_table_size
                                );
                                match HashTable::read(
                                    &mut self.reader,
                                    hash_table_offset,
                                    pow2_entries,
                                ) {
                                    Ok(hash_table) => {
                                        self.hash_table = Some(hash_table);
                                        log::info!("Successfully loaded truncated hash table");
                                    }
                                    Err(e2) => {
                                        log::warn!("Failed to read truncated hash table: {e2}");
                                    }
                                }
                            }
                        }
                    }
                } else {
                    // Normal uncompressed reading
                    match HashTable::read(
                        &mut self.reader,
                        hash_table_offset,
                        self.header.hash_table_size,
                    ) {
                        Ok(hash_table) => {
                            self.hash_table = Some(hash_table);
                        }
                        Err(e) => {
                            log::warn!("Failed to read hash table: {e}");
                        }
                    }
                }
            }
        }

        if self.header.block_table_size > 0 {
            // Load block table
            let block_table_offset = self.archive_offset + self.header.get_block_table_pos();
            let uncompressed_size = self.header.block_table_size as usize * 16; // Each block entry is 16 bytes

            // For V4 archives, we have explicit compressed size info
            if let Some(v4_data) = &self.header.v4_data {
                // Validate V4 sizes are reasonable (not corrupted)
                let file_size = self.reader.get_ref().metadata()?.len();
                let v4_size_valid = v4_data.block_table_size_64 > 0
                    && v4_data.block_table_size_64 < file_size
                    && v4_data.block_table_size_64 < (uncompressed_size as u64 * 2); // Compressed shouldn't be much larger

                if v4_size_valid {
                    // Use compressed size for V4
                    let compressed_size = v4_data.block_table_size_64;

                    log::debug!(
                        "Loading block table from 0x{block_table_offset:X}, compressed size: {compressed_size} bytes, uncompressed size: {uncompressed_size} bytes"
                    );

                    // Check if it would extend beyond file
                    let file_size = self.reader.get_ref().metadata()?.len();
                    if block_table_offset + compressed_size > file_size {
                        log::warn!("Block table extends beyond file, skipping");
                    } else {
                        // Read potentially compressed table
                        match self.read_compressed_table(
                            block_table_offset,
                            compressed_size,
                            uncompressed_size,
                        ) {
                            Ok(table_data) => {
                                // Parse the block table from the decompressed data
                                match BlockTable::from_bytes(
                                    &table_data,
                                    self.header.block_table_size,
                                ) {
                                    Ok(block_table) => {
                                        self.block_table = Some(block_table);
                                    }
                                    Err(e) => {
                                        log::warn!("Failed to parse block table: {e}");
                                    }
                                }
                            }
                            Err(e) => {
                                log::warn!("Failed to decompress block table: {e}");
                            }
                        }
                    }
                } else {
                    // V4 sizes are invalid, fall back to V3-style detection
                    log::warn!(
                        "V4 archive has invalid compressed size ({}), using heuristic detection",
                        v4_data.block_table_size_64
                    );
                    // Fall through to V3-style detection below
                }
            }

            // If we don't have valid V4 data or V4 size was invalid, use heuristic
            if self.block_table.is_none() {
                // For V3 and earlier, or V4 with invalid sizes, we need to detect if tables are compressed
                // Calculate available space for block table
                let file_size = self.reader.get_ref().metadata()?.len();
                let next_section = if let Some(hi_block_pos) = self.header.hi_block_table_pos {
                    if hi_block_pos != 0 {
                        self.archive_offset + hi_block_pos
                    } else {
                        file_size
                    }
                } else {
                    file_size
                };

                let available_space = (next_section.saturating_sub(block_table_offset)) as usize;

                if available_space < uncompressed_size {
                    // Table appears to be compressed
                    log::debug!(
                        "V3 block table appears compressed: available space {available_space} < expected size {uncompressed_size}"
                    );

                    // Try to read as compressed
                    match self.read_compressed_table(
                        block_table_offset,
                        available_space as u64,
                        uncompressed_size,
                    ) {
                        Ok(table_data) => {
                            match BlockTable::from_bytes(&table_data, self.header.block_table_size)
                            {
                                Ok(block_table) => {
                                    self.block_table = Some(block_table);
                                }
                                Err(e) => {
                                    log::warn!("Failed to parse block table: {e}");
                                }
                            }
                        }
                        Err(e) => {
                            log::warn!("Failed to decompress block table: {e}");
                            // Try to read as truncated uncompressed table
                            // Calculate how many entries we can fit in available space
                            let entries_that_fit = available_space / 16; // 16 bytes per entry
                            if entries_that_fit > 0 {
                                log::warn!(
                                    "Trying to read truncated block table with {} entries (originally {})",
                                    entries_that_fit,
                                    self.header.block_table_size
                                );
                                match BlockTable::read(
                                    &mut self.reader,
                                    block_table_offset,
                                    entries_that_fit as u32,
                                ) {
                                    Ok(block_table) => {
                                        self.block_table = Some(block_table);
                                        log::info!("Successfully loaded truncated block table");
                                    }
                                    Err(e2) => {
                                        log::warn!("Failed to read truncated block table: {e2}");
                                    }
                                }
                            }
                        }
                    }
                } else {
                    // Normal uncompressed reading
                    match BlockTable::read(
                        &mut self.reader,
                        block_table_offset,
                        self.header.block_table_size,
                    ) {
                        Ok(block_table) => {
                            self.block_table = Some(block_table);
                        }
                        Err(e) => {
                            log::warn!("Failed to read block table: {e}");
                        }
                    }
                }
            }
        }

        // Load hi-block table if present (v2+)
        if let Some(hi_block_pos) = self.header.hi_block_table_pos
            && hi_block_pos != 0
        {
            let hi_block_offset = self.archive_offset + hi_block_pos;
            let hi_block_end = hi_block_offset + (self.header.block_table_size as u64 * 8);

            let file_size = self.reader.get_ref().metadata()?.len();
            if hi_block_end > file_size {
                log::warn!(
                    "Hi-block table extends beyond file (ends at 0x{hi_block_end:X}, file size 0x{file_size:X}). Skipping."
                );
            } else {
                self.hi_block_table = Some(HiBlockTable::read(
                    &mut self.reader,
                    hi_block_offset,
                    self.header.block_table_size,
                )?);
            }
        }

        // Load attributes if present
        match self.load_attributes() {
            Ok(()) => {}
            Err(e) => {
                log::warn!("Failed to load attributes: {e:?}");
                // Continue without attributes
            }
        }

        Ok(())
    }

    /// Get the archive header
    pub fn header(&self) -> &MpqHeader {
        &self.header
    }

    /// Get the user data header if present
    pub fn user_data(&self) -> Option<&UserDataHeader> {
        self.user_data.as_ref()
    }

    /// Get the archive offset in the file
    pub fn archive_offset(&self) -> u64 {
        self.archive_offset
    }

    /// Get the path to the archive
    pub fn path(&self) -> &Path {
        &self.path
    }

    /// Get the hi-block table if present (v2+ archives)
    pub fn hi_block_table(&self) -> Option<&HiBlockTable> {
        self.hi_block_table.as_ref()
    }

    /// Validate MD5 checksums for v4 archives
    fn validate_v4_md5_checksums(&mut self) -> Result<Option<Md5Status>> {
        use md5::{Digest, Md5};

        let v4_data = match &self.header.v4_data {
            Some(data) => data,
            None => return Ok(None),
        };

        // Helper function to calculate MD5 of raw table data
        let mut validate_table_md5 = |expected: &[u8; 16],
                                      offset: u64,
                                      size: u64|
         -> Result<bool> {
            if size == 0 {
                return Ok(true); // Empty table is valid
            }

            // Read raw table data
            self.reader
                .seek(SeekFrom::Start(self.archive_offset + offset))?;
            let mut table_data = vec![0u8; size as usize];
            match self.reader.read_exact(&mut table_data) {
                Ok(_) => {
                    // Calculate MD5
                    let mut hasher = Md5::new();
                    hasher.update(&table_data);
                    let actual_md5: [u8; 16] = hasher.finalize().into();

                    Ok(actual_md5 == *expected)
                }
                Err(e) => {
                    log::warn!(
                        "Failed to read table data for MD5 validation at offset 0x{:X}, size {}: {}",
                        self.archive_offset + offset,
                        size,
                        e
                    );
                    Ok(false)
                }
            }
        };

        // Validate hash table MD5
        let hash_table_valid = if self.header.hash_table_size > 0 {
            let hash_offset = self.header.get_hash_table_pos();
            let hash_size = v4_data.hash_table_size_64;
            validate_table_md5(&v4_data.md5_hash_table, hash_offset, hash_size)?
        } else {
            true // No hash table to validate
        };

        // Validate block table MD5
        let block_table_valid = if self.header.block_table_size > 0 {
            let block_offset = self.header.get_block_table_pos();
            let block_size = v4_data.block_table_size_64;
            validate_table_md5(&v4_data.md5_block_table, block_offset, block_size)?
        } else {
            true // No block table to validate
        };

        // Validate hi-block table MD5 (if present)
        let hi_block_table_valid = if let Some(hi_pos) = self.header.hi_block_table_pos {
            if hi_pos != 0 {
                let hi_size = v4_data.hi_block_table_size_64;
                validate_table_md5(&v4_data.md5_hi_block_table, hi_pos, hi_size)?
            } else {
                true
            }
        } else {
            true // No hi-block table
        };

        // Validate HET table MD5 (if present)
        let het_table_valid = if let Some(het_pos) = self.header.het_table_pos {
            if het_pos != 0 {
                let het_size = v4_data.het_table_size_64;
                validate_table_md5(&v4_data.md5_het_table, het_pos, het_size)?
            } else {
                true
            }
        } else {
            true // No HET table
        };

        // Validate BET table MD5 (if present)
        let bet_table_valid = if let Some(bet_pos) = self.header.bet_table_pos {
            if bet_pos != 0 {
                let bet_size = v4_data.bet_table_size_64;
                validate_table_md5(&v4_data.md5_bet_table, bet_pos, bet_size)?
            } else {
                true
            }
        } else {
            true // No BET table
        };

        // Validate header MD5 (first 192 bytes of header, excluding the MD5 field itself)
        let header_valid = {
            self.reader.seek(SeekFrom::Start(self.archive_offset))?;
            let mut header_data = vec![0u8; 192];
            match self.reader.read_exact(&mut header_data) {
                Ok(_) => {
                    let mut hasher = Md5::new();
                    hasher.update(&header_data);
                    let actual_md5: [u8; 16] = hasher.finalize().into();

                    actual_md5 == v4_data.md5_mpq_header
                }
                Err(e) => {
                    log::warn!("Failed to read header for MD5 validation: {e}");
                    false
                }
            }
        };

        Ok(Some(Md5Status {
            hash_table_valid,
            block_table_valid,
            hi_block_table_valid,
            het_table_valid,
            bet_table_valid,
            header_valid,
        }))
    }

    /// Get detailed information about the archive
    pub fn get_info(&mut self) -> Result<ArchiveInfo> {
        log::debug!("Getting archive info");

        // Ensure tables are loaded
        if self.hash_table.is_none() && self.het_table.is_none() {
            log::debug!("Loading tables for info");
            self.load_tables()?;
        }

        // Get file size
        log::debug!("Getting file size");
        let file_size = self.reader.get_ref().metadata()?.len();

        // Count files
        let file_count = if let Some(bet) = &self.bet_table {
            bet.header.file_count as usize
        } else if let Some(block_table) = &self.block_table {
            // Count non-empty entries in block table
            block_table
                .entries()
                .iter()
                .filter(|entry| entry.file_size != 0)
                .count()
        } else {
            0
        };

        // Get max file count
        let max_file_count = if let Some(het) = &self.het_table {
            het.header.max_file_count
        } else {
            self.header.hash_table_size
        };

        // Check for special files
        let has_listfile = self.find_file("(listfile)")?.is_some();
        let has_signature = self.find_file("(signature)")?.is_some();
        let has_attributes = self.attributes.is_some() || self.find_file("(attributes)")?.is_some();

        // Determine encryption status
        let is_encrypted = if let Some(block_table) = &self.block_table {
            use crate::tables::BlockEntry;
            block_table
                .entries()
                .iter()
                .any(|entry| (entry.flags & BlockEntry::FLAG_ENCRYPTED) != 0)
        } else {
            false
        };

        // Verify signature if present
        let signature_status = if has_signature {
            match self.verify_signature() {
                Ok(status) => status,
                Err(e) => {
                    log::warn!("Failed to verify signature: {e}");
                    SignatureStatus::WeakInvalid
                }
            }
        } else {
            SignatureStatus::None
        };

        // Build table info
        let hash_table_info = TableInfo {
            size: Some(self.header.hash_table_size),
            offset: self.header.get_hash_table_pos(),
            compressed_size: self.header.v4_data.as_ref().map(|v4| v4.hash_table_size_64),
            failed_to_load: self.hash_table.is_none() && self.header.hash_table_size > 0,
        };

        let block_table_info = TableInfo {
            size: Some(self.header.block_table_size),
            offset: self.header.get_block_table_pos(),
            compressed_size: self
                .header
                .v4_data
                .as_ref()
                .map(|v4| v4.block_table_size_64),
            failed_to_load: self.block_table.is_none() && self.header.block_table_size > 0,
        };

        let het_table_info = self.header.het_table_pos.and_then(|pos| {
            if pos == 0 {
                return None;
            }

            // For v4, use the size from v4 data
            let mut compressed_size = self.header.v4_data.as_ref().map(|v4| v4.het_table_size_64);

            // For v3 without v4 data, try to determine the size
            if compressed_size.is_none() && self.header.format_version == header::FormatVersion::V3
            {
                // Make a copy of the reader to avoid interfering with the main archive
                if let Ok(temp_reader) =
                    std::fs::File::open(&self.path).map(std::io::BufReader::new)
                {
                    let mut temp_archive = Self {
                        path: self.path.clone(),
                        reader: temp_reader,
                        archive_offset: self.archive_offset,
                        user_data: self.user_data.clone(),
                        header: self.header.clone(),
                        hash_table: None,
                        block_table: None,
                        hi_block_table: None,
                        het_table: None,
                        bet_table: None,
                        attributes: None,
                    };

                    if let Ok(size) = temp_archive.read_het_table_size(pos) {
                        compressed_size = Some(size);
                    }
                }
            }

            Some(TableInfo {
                size: self.het_table.as_ref().map(|het| het.header.max_file_count),
                offset: pos,
                compressed_size,
                failed_to_load: self.het_table.is_none(),
            })
        });

        let bet_table_info = self.header.bet_table_pos.and_then(|pos| {
            if pos == 0 {
                return None;
            }

            // For v4, use the size from v4 data
            let mut compressed_size = self.header.v4_data.as_ref().map(|v4| v4.bet_table_size_64);

            // For v3 without v4 data, try to determine the size
            if compressed_size.is_none() && self.header.format_version == header::FormatVersion::V3
            {
                // Make a copy of the reader to avoid interfering with the main archive
                if let Ok(temp_reader) =
                    std::fs::File::open(&self.path).map(std::io::BufReader::new)
                {
                    let mut temp_archive = Self {
                        path: self.path.clone(),
                        reader: temp_reader,
                        archive_offset: self.archive_offset,
                        user_data: self.user_data.clone(),
                        header: self.header.clone(),
                        hash_table: None,
                        block_table: None,
                        hi_block_table: None,
                        het_table: None,
                        bet_table: None,
                        attributes: None,
                    };

                    if let Ok(size) = temp_archive.read_bet_table_size(pos) {
                        compressed_size = Some(size);
                    }
                }
            }

            Some(TableInfo {
                size: self.bet_table.as_ref().map(|bet| bet.header.file_count),
                offset: pos,
                compressed_size,
                failed_to_load: self.bet_table.is_none(),
            })
        });

        let hi_block_table_info = self.header.hi_block_table_pos.and_then(|pos| {
            if pos == 0 {
                return None;
            }

            Some(TableInfo {
                size: if self.hi_block_table.is_some() {
                    Some(self.header.block_table_size)
                } else {
                    None
                },
                offset: pos,
                compressed_size: self
                    .header
                    .v4_data
                    .as_ref()
                    .map(|v4| v4.hi_block_table_size_64),
                failed_to_load: self.hi_block_table.is_none(),
            })
        });

        let user_data_info = self.user_data.as_ref().map(|ud| UserDataInfo {
            header_size: ud.user_data_header_size,
            data_size: ud.user_data_size,
        });

        // MD5 verification for v4 archives
        let md5_status = if self.header.v4_data.is_some() {
            self.validate_v4_md5_checksums()?
        } else {
            None
        };

        Ok(ArchiveInfo {
            path: self.path.clone(),
            file_size,
            archive_offset: self.archive_offset,
            format_version: self.header.format_version,
            file_count,
            max_file_count,
            sector_size: self.header.sector_size(),
            is_encrypted,
            has_signature,
            signature_status,
            hash_table_info,
            block_table_info,
            het_table_info,
            bet_table_info,
            hi_block_table_info,
            has_attributes,
            has_listfile,
            user_data_info,
            md5_status,
        })
    }

    /// Get the hash table
    pub fn hash_table(&self) -> Option<&HashTable> {
        self.hash_table.as_ref()
    }

    /// Get the block table
    pub fn block_table(&self) -> Option<&BlockTable> {
        self.block_table.as_ref()
    }

    /// Get HET table reference
    pub fn het_table(&self) -> Option<&HetTable> {
        self.het_table.as_ref()
    }

    /// Get BET table reference
    pub fn bet_table(&self) -> Option<&BetTable> {
        self.bet_table.as_ref()
    }

    /// Find a file in the archive
    pub fn find_file(&self, filename: &str) -> Result<Option<FileInfo>> {
        // Check if this is a special file that should be searched in both table types
        let is_special_file = matches!(
            filename,
            "(listfile)" | "(attributes)" | "(signature)" | "(patch_metadata)"
        );

        // For v3+ archives, prioritize HET/BET tables if they exist and are valid
        if let (Some(het), Some(bet)) = (&self.het_table, &self.bet_table) {
            // Check if tables have actual entries
            if het.header.max_file_count > 0 && bet.header.file_count > 0 {
                let (_file_index_opt, collision_candidates) =
                    het.find_file_with_collision_info(filename);

                // HET uses 8-bit hashes which naturally have many collisions.
                // We must verify each candidate against the full BET hash to find the correct file.
                if !collision_candidates.is_empty() {
                    if collision_candidates.len() > 1 {
                        log::debug!(
                            "HET: '{}' has {} collision candidates, verifying against BET hashes",
                            filename,
                            collision_candidates.len()
                        );
                    }

                    // Check each collision candidate against BET hash
                    for &candidate_index in &collision_candidates {
                        // Verify this candidate has the correct BET hash
                        if bet.verify_file_hash(candidate_index, filename) {
                            // Found the correct file - return its info
                            if let Some(bet_info) = bet.get_file_info(candidate_index) {
                                log::debug!(
                                    "HET/BET: Found '{}' at file_index={} (verified by BET hash)",
                                    filename,
                                    candidate_index
                                );
                                return Ok(Some(FileInfo {
                                    filename: filename.to_string(),
                                    hash_index: 0, // Not applicable for HET/BET
                                    block_index: candidate_index as usize,
                                    file_pos: self.archive_offset + bet_info.file_pos,
                                    compressed_size: bet_info.compressed_size,
                                    file_size: bet_info.file_size,
                                    flags: bet_info.flags,
                                    locale: 0, // HET/BET don't store locale separately
                                }));
                            }
                        }
                    }

                    // No candidate matched - file not found in HET/BET
                    log::debug!(
                        "HET/BET: '{}' not found - {} candidates checked, none matched BET hash",
                        filename,
                        collision_candidates.len()
                    );
                }

                // For special files, always check hash/block tables as fallback
                // For regular files, only fall back if hash tables exist
                if !is_special_file && (self.hash_table.is_none() || self.block_table.is_none()) {
                    return Ok(None);
                }
            }
        }

        // Fall back to traditional hash/block tables if:
        // 1. HET/BET tables don't exist
        // 2. HET/BET tables are empty/invalid
        // 3. File wasn't found in HET/BET but we're looking for a special file
        // 4. File wasn't found in HET/BET but hash/block tables exist
        self.find_file_classic(filename)
    }

    /// Classic file lookup using hash/block tables
    fn find_file_classic(&self, filename: &str) -> Result<Option<FileInfo>> {
        // If tables aren't loaded, return None instead of error
        // This is common for V3+ archives that only have HET/BET tables
        let hash_table = match self.hash_table.as_ref() {
            Some(table) => table,
            None => return Ok(None),
        };
        let block_table = match self.block_table.as_ref() {
            Some(table) => table,
            None => return Ok(None),
        };

        // Try to find the file with default locale
        if let Some((hash_index, hash_entry)) = hash_table.find_file(filename, 0) {
            let block_entry = block_table
                .get(hash_entry.block_index as usize)
                .ok_or_else(|| Error::block_table("Invalid block index"))?;

            // Calculate full file position for v2+ archives
            let file_pos = if let Some(hi_block) = &self.hi_block_table {
                let high_bits = hi_block.get_file_pos_high(hash_entry.block_index as usize);
                (high_bits << 32) | (block_entry.file_pos as u64)
            } else {
                block_entry.file_pos as u64
            };

            Ok(Some(FileInfo {
                filename: filename.to_string(),
                hash_index,
                block_index: hash_entry.block_index as usize,
                file_pos: self.archive_offset + file_pos,
                compressed_size: block_entry.compressed_size as u64,
                file_size: block_entry.file_size as u64,
                flags: block_entry.flags,
                locale: hash_entry.locale,
            }))
        } else {
            Ok(None)
        }
    }

    /// List files in the archive
    pub fn list(&mut self) -> Result<Vec<FileEntry>> {
        // Try to find and read (listfile)
        if let Some(_listfile_info) = self.find_file("(listfile)")? {
            // Try to read the listfile
            match self.read_file("(listfile)") {
                Ok(listfile_data) => {
                    // Parse the listfile
                    match special_files::parse_listfile(&listfile_data) {
                        Ok(filenames) => {
                            let mut entries = Vec::new();

                            // Look up each file
                            for filename in filenames {
                                if let Some(file_info) = self.find_file(&filename)? {
                                    entries.push(FileEntry {
                                        name: filename,
                                        size: file_info.file_size,
                                        compressed_size: file_info.compressed_size,
                                        flags: file_info.flags,
                                        hashes: None,
                                        table_indices: Some((
                                            file_info.hash_index,
                                            Some(file_info.block_index),
                                        )),
                                    });
                                } else {
                                    // File is in listfile but not found in archive
                                    log::warn!(
                                        "File '{filename}' listed in (listfile) but not found in archive"
                                    );
                                }
                            }

                            return Ok(entries);
                        }
                        Err(e) => {
                            log::warn!(
                                "Failed to parse (listfile): {e}. Falling back to anonymous enumeration."
                            );
                        }
                    }
                }
                Err(e) => {
                    log::warn!(
                        "Failed to read (listfile): {e}. Falling back to anonymous enumeration."
                    );
                }
            }
        }

        // No listfile or failed to read/parse it, we'll need to enumerate entries without names
        log::info!("Enumerating anonymous entries");

        let mut entries = Vec::new();

        // For v3+ archives, prioritize HET/BET tables if they exist and are valid
        if let (Some(het), Some(bet)) = (&self.het_table, &self.bet_table)
            && het.header.max_file_count > 0
            && bet.header.file_count > 0
        {
            log::info!("Enumerating files using HET/BET tables");

            // Enumerate using BET table
            for i in 0..bet.header.file_count {
                if let Some(bet_info) = bet.get_file_info(i) {
                    // Only include files that actually exist
                    if bet_info.flags & crate::tables::BlockEntry::FLAG_EXISTS != 0 {
                        entries.push(FileEntry {
                            name: format!("file_{i:08}.dat"), // Unknown name with file index
                            size: bet_info.file_size,
                            compressed_size: bet_info.compressed_size,
                            flags: bet_info.flags,
                            hashes: None,
                            table_indices: Some((i as usize, None)), // file_index for HET/BET tables
                        });
                    }
                }
            }

            // If we enumerated from HET/BET successfully, return early
            if !entries.is_empty() {
                return Ok(entries);
            }
        }

        // Fall back to classic hash/block tables
        let hash_table = self
            .hash_table
            .as_ref()
            .ok_or_else(|| Error::invalid_format("No tables loaded for enumeration"))?;
        let block_table = self
            .block_table
            .as_ref()
            .ok_or_else(|| Error::invalid_format("No block table loaded"))?;

        log::info!("Enumerating files using hash/block tables");

        // Scan hash table for valid entries
        for (i, hash_entry) in hash_table.entries().iter().enumerate() {
            if hash_entry.is_valid()
                && let Some(block_entry) = block_table.get(hash_entry.block_index as usize)
                && block_entry.exists()
            {
                entries.push(FileEntry {
                    name: format!("file_{i:08}.dat"), // Unknown name with hash index
                    size: block_entry.file_size as u64,
                    compressed_size: block_entry.compressed_size as u64,
                    flags: block_entry.flags,
                    hashes: None,
                    table_indices: Some((i, Some(hash_entry.block_index as usize))), // hash_index, block_index
                });
            }
        }

        Ok(entries)
    }

    /// List all files in the archive by enumerating tables
    /// This shows all entries, using generic names for files not in listfile
    pub fn list_all(&mut self) -> Result<Vec<FileEntry>> {
        let mut entries = Vec::new();

        // For v3+ archives, prioritize HET/BET tables if they exist and are valid
        if let (Some(het), Some(bet)) = (&self.het_table, &self.bet_table)
            && het.header.max_file_count > 0
            && bet.header.file_count > 0
        {
            log::info!("Enumerating all files using HET/BET tables");

            // Enumerate using BET table
            for i in 0..bet.header.file_count {
                if let Some(bet_info) = bet.get_file_info(i) {
                    // Only include files that actually exist
                    if bet_info.flags & crate::tables::BlockEntry::FLAG_EXISTS != 0 {
                        entries.push(FileEntry {
                            name: format!("file_{i:08}.dat"), // Unknown name with file index
                            size: bet_info.file_size,
                            compressed_size: bet_info.compressed_size,
                            flags: bet_info.flags,
                            hashes: None,
                            table_indices: Some((i as usize, None)), // file_index for HET/BET tables
                        });
                    }
                }
            }

            // If we enumerated from HET/BET successfully, return early
            if !entries.is_empty() {
                return Ok(entries);
            }
        }

        // Fall back to classic hash/block tables
        let hash_table = self
            .hash_table
            .as_ref()
            .ok_or_else(|| Error::invalid_format("No tables loaded for enumeration"))?;
        let block_table = self
            .block_table
            .as_ref()
            .ok_or_else(|| Error::invalid_format("No block table loaded"))?;

        log::info!("Enumerating all files using hash/block tables");

        // Enumerate all hash table entries
        let mut block_indices_seen = std::collections::HashSet::new();

        for hash_entry in hash_table.entries().iter() {
            if hash_entry.is_valid() {
                let block_index = hash_entry.block_index as usize;

                // Skip if we've already seen this block index (collision chain)
                if !block_indices_seen.insert(block_index) {
                    continue;
                }

                if let Some(block_entry) = block_table.get(block_index)
                    && block_entry.exists()
                {
                    entries.push(FileEntry {
                        name: format!("file_{block_index:08}.dat"),
                        size: block_entry.file_size as u64,
                        compressed_size: block_entry.compressed_size as u64,
                        flags: block_entry.flags,
                        hashes: None,
                        table_indices: Some((0, Some(block_index))), // Use 0 for hash_index since we don't track it here
                    });
                }
            }
        }

        // Sort by block index (which is embedded in the generated names)
        entries.sort_by(|a, b| a.name.cmp(&b.name));

        Ok(entries)
    }

    /// List files in the archive with hash information
    pub fn list_with_hashes(&mut self) -> Result<Vec<FileEntry>> {
        let mut entries = self.list()?;

        // Calculate hashes for each entry
        for entry in &mut entries {
            let hash1 = crate::crypto::hash_string(&entry.name, crate::crypto::hash_type::NAME_A);
            let hash2 = crate::crypto::hash_string(&entry.name, crate::crypto::hash_type::NAME_B);
            entry.hashes = Some((hash1, hash2));
        }

        Ok(entries)
    }

    /// List all files in the archive by enumerating tables with hash information
    pub fn list_all_with_hashes(&mut self) -> Result<Vec<FileEntry>> {
        let mut entries = Vec::new();

        // For v3+ archives, use HET/BET tables
        if let (Some(het), Some(bet)) = (&self.het_table, &self.bet_table)
            && het.header.max_file_count > 0
            && bet.header.file_count > 0
        {
            log::info!("Enumerating all files using HET/BET tables with hashes");

            // Enumerate using BET table
            for i in 0..bet.header.file_count {
                if let Some(bet_info) = bet.get_file_info(i)
                    && bet_info.flags & crate::tables::BlockEntry::FLAG_EXISTS != 0
                {
                    entries.push(FileEntry {
                        name: format!("file_{i:08}.dat"),
                        size: bet_info.file_size,
                        compressed_size: bet_info.compressed_size,
                        flags: bet_info.flags,
                        hashes: None, // HET/BET doesn't expose name hashes directly
                        table_indices: Some((i as usize, None)), // file_index for HET/BET tables
                    });
                }
            }

            if !entries.is_empty() {
                return Ok(entries);
            }
        }

        // Fall back to classic hash/block tables
        let hash_table = self
            .hash_table
            .as_ref()
            .ok_or_else(|| Error::invalid_format("No tables loaded for enumeration"))?;
        let block_table = self
            .block_table
            .as_ref()
            .ok_or_else(|| Error::invalid_format("No block table loaded"))?;

        log::info!("Enumerating all files using hash/block tables with hashes");

        // Enumerate all hash table entries - here we can get the actual hashes!
        let mut block_indices_seen = std::collections::HashSet::new();

        for hash_entry in hash_table.entries().iter() {
            if hash_entry.is_valid() {
                let block_index = hash_entry.block_index as usize;

                if !block_indices_seen.insert(block_index) {
                    continue;
                }

                if let Some(block_entry) = block_table.get(block_index)
                    && block_entry.exists()
                {
                    entries.push(FileEntry {
                        name: format!("file_{block_index:08}.dat"),
                        size: block_entry.file_size as u64,
                        compressed_size: block_entry.compressed_size as u64,
                        flags: block_entry.flags,
                        hashes: Some((hash_entry.name_1, hash_entry.name_2)),
                        table_indices: Some((0, Some(block_index))), // Use 0 for hash_index since we don't track it here
                    });
                }
            }
        }

        // Sort by block index
        entries.sort_by(|a, b| a.name.cmp(&b.name));

        Ok(entries)
    }

    /// Read a file from the archive
    pub fn read_file(&mut self, name: &str) -> Result<Vec<u8>> {
        let file_info = self
            .find_file(name)?
            .ok_or_else(|| Error::FileNotFound(name.to_string()))?;

        // Check if this is a patch file - patch files cannot be read directly
        if file_info.is_patch_file() {
            return Err(Error::OperationNotSupported {
                version: self.header.format_version as u16,
                operation: format!(
                    "Reading patch file '{name}' directly. Patch files contain binary patches that must be applied to base files."
                ),
            });
        }

        // For v3+ archives with HET/BET tables, we already have all the info we need in FileInfo
        // For classic archives, we need to get additional info from the block table
        let (file_size_for_key, actual_file_size) =
            if self.het_table.is_some() && self.bet_table.is_some() {
                // Using HET/BET tables - FileInfo already has all the data
                (file_info.file_size as u32, file_info.file_size)
            } else {
                // Using classic tables - need block entry for accurate sizes
                let block_table = self
                    .block_table
                    .as_ref()
                    .ok_or_else(|| Error::invalid_format("Block table not loaded"))?;
                let block_entry = block_table
                    .get(file_info.block_index)
                    .ok_or_else(|| Error::block_table("Invalid block index"))?;
                (block_entry.file_size, block_entry.file_size as u64)
            };

        // Calculate encryption key if needed
        let key = if file_info.is_encrypted() {
            let base_key = hash_string(name, hash_type::FILE_KEY);
            if file_info.has_fix_key() {
                // Apply FIX_KEY modification
                let file_pos = (file_info.file_pos - self.archive_offset) as u32;
                (base_key.wrapping_add(file_pos)) ^ file_size_for_key
            } else {
                base_key
            }
        } else {
            0
        };

        // Read the file data
        self.reader.seek(SeekFrom::Start(file_info.file_pos))?;

        if file_info.is_single_unit() || !file_info.is_compressed() {
            // Single unit or uncompressed file - read directly
            let mut data = vec![0u8; file_info.compressed_size as usize];
            self.reader.read_exact(&mut data)?;

            // Decrypt if needed
            if file_info.is_encrypted() {
                log::debug!(
                    "Decrypting file data: key=0x{:08X}, size={}",
                    key,
                    data.len()
                );
                if data.len() <= 64 {
                    log::debug!("Before decrypt: {:02X?}", &data);
                }
                decrypt_file_data(&mut data, key);
                if data.len() <= 64 {
                    log::debug!("After decrypt: {:02X?}", &data);
                }
            }

            // Validate CRC if present for single unit files
            if file_info.has_sector_crc() && file_info.is_single_unit() {
                // For single unit files, there's one CRC after the data
                let mut crc_bytes = [0u8; 4];
                self.reader.read_exact(&mut crc_bytes)?;
                let expected_crc = u32::from_le_bytes(crc_bytes);

                // CRC is calculated on the decompressed data
                let data_to_check = if file_info.is_compressed() {
                    // We need to decompress first to check CRC
                    let compression_type = data[0];
                    let compressed_data = &data[1..];
                    compression::decompress(
                        compressed_data,
                        compression_type,
                        actual_file_size as usize,
                    )?
                } else {
                    data.clone()
                };

                // MPQ uses ADLER32 for sector checksums, not CRC32 despite the name
                let actual_crc = adler2::adler32_slice(&data_to_check);
                if actual_crc != expected_crc {
                    return Err(Error::ChecksumMismatch {
                        file: name.to_string(),
                        expected: expected_crc,
                        actual: actual_crc,
                    });
                }

                log::debug!("Single unit file CRC validated: 0x{actual_crc:08X}");
            }

            // Decompress if needed
            if file_info.is_compressed() {
                if file_info.is_single_unit() {
                    // SINGLE_UNIT files: Get compression method from block table flags
                    // NO compression type byte prefix in the data

                    // Special case: If compressed_size == file_size, the file might be stored uncompressed
                    // despite having the COMPRESS flag set
                    if data.len() == actual_file_size as usize {
                        log::debug!(
                            "SINGLE_UNIT file has equal compressed/uncompressed size ({} bytes), trying uncompressed first",
                            data.len()
                        );

                        // Try treating as uncompressed data first
                        // This handles cases where the COMPRESS flag is set but data is actually uncompressed
                        Ok(data)
                    } else if let Some(compression_method) = file_info.get_compression_method() {
                        // SINGLE_UNIT files DO have compression method byte prefix!
                        // This was our bug - we thought they didn't
                        if !data.is_empty() {
                            let actual_compression_method = data[0];
                            let compressed_data = &data[1..];

                            log::debug!(
                                "Decompressing SINGLE_UNIT file: method_from_flags=0x{:02X}, actual_method_byte=0x{:02X}, compressed_size={}, expected_size={}",
                                compression_method,
                                actual_compression_method,
                                compressed_data.len(),
                                actual_file_size
                            );

                            // Use the actual compression method from the data, not from flags
                            // This ensures we handle multi-compression correctly
                            compression::decompress(
                                compressed_data,
                                actual_compression_method,
                                actual_file_size as usize,
                            )
                        } else {
                            Err(Error::compression("Empty compressed data"))
                        }
                    } else {
                        Err(Error::compression(
                            "Could not determine compression method from flags",
                        ))
                    }
                } else {
                    // SECTORED files: Should not reach here for single-unit code path
                    // This will be handled in read_sectored_file()
                    log::warn!("Non-single-unit compressed file in single-unit code path");
                    Ok(data)
                }
            } else {
                // For encrypted files, trim to original file size to remove padding
                if file_info.is_encrypted() && data.len() > actual_file_size as usize {
                    data.truncate(actual_file_size as usize);
                }
                Ok(data)
            }
        } else {
            // Multi-sector compressed file
            self.read_sectored_file(&file_info, key)
        }
    }

    /// Read raw patch file data
    ///
    /// This method reads patch files (files with MPQ_FILE_PATCH_FILE flag) without
    /// rejecting them. It returns the raw PTCH format data that can be parsed and
    /// applied to base files.
    ///
    /// This is used internally by PatchChain to read patch files for application.
    pub(crate) fn read_patch_file_raw(&mut self, name: &str) -> Result<Vec<u8>> {
        let file_info = self
            .find_file(name)?
            .ok_or_else(|| Error::FileNotFound(name.to_string()))?;

        // Verify this is actually a patch file
        if !file_info.is_patch_file() {
            return Err(Error::invalid_format(format!(
                "File '{name}' is not a patch file"
            )));
        }

        // For v3+ archives with HET/BET tables, we already have all the info we need in FileInfo
        // For classic archives, we need to get additional info from the block table
        let (file_size_for_key, _actual_file_size) =
            if self.het_table.is_some() && self.bet_table.is_some() {
                // Using HET/BET tables - FileInfo already has all the data
                (file_info.file_size as u32, file_info.file_size)
            } else {
                // Using classic tables - need block entry for accurate sizes
                let block_table = self
                    .block_table
                    .as_ref()
                    .ok_or_else(|| Error::invalid_format("Block table not loaded"))?;
                let block_entry = block_table
                    .get(file_info.block_index)
                    .ok_or_else(|| Error::block_table("Invalid block index"))?;
                (block_entry.file_size, block_entry.file_size as u64)
            };

        // Calculate encryption key if needed
        let key = if file_info.is_encrypted() {
            let base_key = hash_string(name, hash_type::FILE_KEY);
            if file_info.has_fix_key() {
                // Apply FIX_KEY modification
                let file_pos = (file_info.file_pos - self.archive_offset) as u32;
                (base_key.wrapping_add(file_pos)) ^ file_size_for_key
            } else {
                base_key
            }
        } else {
            0
        };

        // Read the file data
        // Patch files start with TPatchInfo structure (uncompressed metadata)
        self.reader.seek(SeekFrom::Start(file_info.file_pos))?;

        // Read TPatchInfo header (28 bytes minimum)
        let mut patch_info_buf = [0u8; 28];
        self.reader.read_exact(&mut patch_info_buf)?;

        let patch_info_length = u32::from_le_bytes([
            patch_info_buf[0],
            patch_info_buf[1],
            patch_info_buf[2],
            patch_info_buf[3],
        ]);
        let patch_info_flags = u32::from_le_bytes([
            patch_info_buf[4],
            patch_info_buf[5],
            patch_info_buf[6],
            patch_info_buf[7],
        ]);
        let patch_data_size = u32::from_le_bytes([
            patch_info_buf[8],
            patch_info_buf[9],
            patch_info_buf[10],
            patch_info_buf[11],
        ]);

        log::debug!(
            "TPatchInfo: length={}, flags=0x{:08X}, data_size={} bytes",
            patch_info_length,
            patch_info_flags,
            patch_data_size
        );

        // The actual decompressed size is patch_data_size, not file_info.file_size!
        let actual_patch_size = patch_data_size as usize;

        // After TPatchInfo, check if file is sectored or single-unit
        // Patch files can be sectored despite lacking the SINGLE_UNIT flag
        let is_single_unit = file_info.is_single_unit();

        if is_single_unit {
            log::debug!("Patch file is stored as single unit");
            let compressed_data_size =
                file_info.compressed_size as usize - patch_info_length as usize;

            let mut data = vec![0u8; compressed_data_size];
            self.reader.read_exact(&mut data)?;

            log::debug!(
                "Read {} bytes of compressed patch data (single unit)",
                data.len()
            );
            log::debug!("First 32 bytes: {:02X?}", &data[..32.min(data.len())]);

            // Decrypt if needed (though patch files are typically not encrypted)
            if file_info.is_encrypted() {
                log::debug!(
                    "Decrypting patch file data: key=0x{:08X}, size={}",
                    key,
                    data.len()
                );
                decrypt_file_data(&mut data, key);
            }

            // Decompress if needed
            if file_info.is_compressed() {
                let compression_type = data[0];
                let compressed_data = &data[1..];

                log::debug!(
                    "Decompressing patch file (single unit): method=0x{:02X}, compressed={} bytes → {} bytes",
                    compression_type,
                    compressed_data.len(),
                    actual_patch_size
                );

                compression::decompress(compressed_data, compression_type, actual_patch_size)
            } else {
                Ok(data)
            }
        } else {
            // Sectored patch file - read using sector table
            log::debug!("Patch file is sectored, reading with modified sector handling");

            // Calculate sector count based on patch_data_size, not file_size
            let sector_size = self.header.sector_size();
            let sector_count = (patch_data_size as usize).div_ceil(sector_size);

            log::debug!(
                "Patch sectors: data_size={}, sector_size={}, sector_count={}",
                patch_data_size,
                sector_size,
                sector_count
            );

            // Read sector offset table
            let offset_table_size = (sector_count + 1) * 4;
            let mut offset_data = vec![0u8; offset_table_size];
            self.reader.read_exact(&mut offset_data)?;

            log::debug!(
                "Read sector offset table: {} bytes for {} sectors",
                offset_table_size,
                sector_count
            );

            // Parse sector offsets
            let mut sector_offsets = Vec::with_capacity(sector_count + 1);
            let mut cursor = std::io::Cursor::new(&offset_data);
            for _ in 0..=sector_count {
                sector_offsets.push(cursor.read_u32::<LittleEndian>()?);
            }

            log::debug!("Sector offsets: {:?}", &sector_offsets);

            // Read and decompress each sector
            let mut decompressed_data = Vec::with_capacity(patch_data_size as usize);

            for i in 0..sector_count {
                let sector_start = sector_offsets[i] as usize;
                let sector_end = sector_offsets[i + 1] as usize;
                let sector_compressed_size = sector_end - sector_start;

                log::debug!(
                    "Reading sector {}: offset={}, size={} bytes",
                    i,
                    sector_start,
                    sector_compressed_size
                );

                // Sector offsets are relative to the START of the offset table, NOT after it
                // So we need to seek to: file_pos + TPatchInfo + sector_offset
                let sector_file_pos =
                    file_info.file_pos + patch_info_length as u64 + sector_start as u64;

                self.reader.seek(SeekFrom::Start(sector_file_pos))?;

                let mut sector_data = vec![0u8; sector_compressed_size];
                self.reader.read_exact(&mut sector_data)?;

                log::debug!(
                    "Sector {} data first 16 bytes: {:02X?}",
                    i,
                    &sector_data[..16.min(sector_data.len())]
                );

                // Patch file sectors use standard MPQ compression (Zlib/BZip2/etc)
                // First byte indicates compression method, remaining bytes are compressed PTCH data
                let compression_method = sector_data[0];
                log::debug!(
                    "Decompressing sector {} with method 0x{:02X} ({} bytes compressed)",
                    i,
                    compression_method,
                    sector_data.len() - 1
                );

                // Decompress using standard MPQ decompression
                let expected_size =
                    sector_size.min(patch_data_size as usize - decompressed_data.len());
                let sector_decompressed = compression::decompress(
                    &sector_data[1..], // Skip compression method byte
                    compression_method,
                    expected_size,
                )?;

                log::debug!(
                    "Sector {} decompressed to {} bytes",
                    i,
                    sector_decompressed.len()
                );

                decompressed_data.extend_from_slice(&sector_decompressed);
            }

            log::debug!(
                "Successfully decompressed {} bytes from {} sectors",
                decompressed_data.len(),
                sector_count
            );

            Ok(decompressed_data)
        }
    }

    /// Read a file by table indices (for files with generic names)
    pub fn read_file_by_indices(
        &mut self,
        hash_index: usize,
        block_index: Option<usize>,
    ) -> Result<Vec<u8>> {
        let file_info = if let Some(block_idx) = block_index {
            // Classic hash/block table access
            let hash_table = self
                .hash_table
                .as_ref()
                .ok_or_else(|| Error::invalid_format("Hash table not loaded"))?;
            let block_table = self
                .block_table
                .as_ref()
                .ok_or_else(|| Error::invalid_format("Block table not loaded"))?;

            let hash_entry = hash_table
                .entries()
                .get(hash_index)
                .ok_or_else(|| Error::hash_table("Invalid hash index"))?;
            let block_entry = block_table
                .get(block_idx)
                .ok_or_else(|| Error::block_table("Invalid block index"))?;

            // Calculate full file position for v2+ archives
            let file_pos = if let Some(hi_block) = &self.hi_block_table {
                let high_bits = hi_block.get_file_pos_high(block_idx);
                (high_bits << 32) | (block_entry.file_pos as u64)
            } else {
                block_entry.file_pos as u64
            };

            FileInfo {
                filename: format!("file_{hash_index:08}.dat"),
                hash_index,
                block_index: block_idx,
                file_pos: self.archive_offset + file_pos,
                compressed_size: block_entry.compressed_size as u64,
                file_size: block_entry.file_size as u64,
                flags: block_entry.flags,
                locale: hash_entry.locale,
            }
        } else {
            // HET/BET table access (file_index is in hash_index parameter)
            let bet = self
                .bet_table
                .as_ref()
                .ok_or_else(|| Error::invalid_format("BET table not loaded"))?;

            let bet_info = bet
                .get_file_info(hash_index as u32)
                .ok_or_else(|| Error::invalid_format("Invalid file index"))?;

            // For HET/BET files, the file position is calculated differently
            let file_pos = self.archive_offset + bet_info.file_pos;

            FileInfo {
                filename: format!("file_{hash_index:08}.dat"),
                hash_index: 0,  // Not meaningful for HET/BET
                block_index: 0, // Not meaningful for HET/BET
                file_pos,
                compressed_size: bet_info.compressed_size,
                file_size: bet_info.file_size,
                flags: bet_info.flags,
                locale: 0, // Not applicable for HET/BET
            }
        };

        // Check if this is a patch file - patch files cannot be read directly
        if file_info.is_patch_file() {
            return Err(Error::OperationNotSupported {
                version: self.header.format_version as u16,
                operation: format!(
                    "Reading patch file '{}' directly. Patch files contain binary patches that must be applied to base files.",
                    file_info.filename
                ),
            });
        }

        // Now use the existing file reading logic
        // For encrypted files, we need a key. Since we don't have the real filename,
        // we'll use a default key based on the table index
        let key = if file_info.is_encrypted() {
            // Use a generic key calculation for anonymous files
            hash_string(&file_info.filename, hash_type::FILE_KEY)
        } else {
            0
        };

        // Continue with normal file reading logic based on whether it's sectored
        let (file_size_for_key, actual_file_size) =
            if self.het_table.is_some() && self.bet_table.is_some() {
                // Using HET/BET tables - FileInfo already has all the data
                (file_info.file_size as u32, file_info.file_size)
            } else {
                // Using classic tables - need block entry for accurate sizes
                let block_table = self
                    .block_table
                    .as_ref()
                    .ok_or_else(|| Error::invalid_format("Block table not loaded"))?;
                let block_entry = block_table
                    .get(file_info.block_index)
                    .ok_or_else(|| Error::block_table("Invalid block index"))?;
                (block_entry.file_size, block_entry.file_size as u64)
            };

        // Adjust key for file size if needed
        let key = if file_info.is_encrypted() && file_info.has_fix_key() {
            key.wrapping_add(file_size_for_key)
        } else {
            key
        };

        // Read the file data
        self.reader.seek(SeekFrom::Start(file_info.file_pos))?;

        if file_info.is_single_unit() || !file_info.is_compressed() {
            // Single unit or uncompressed file - read directly
            let mut data = vec![0u8; file_info.compressed_size as usize];
            self.reader.read_exact(&mut data)?;

            // Decrypt if needed
            if file_info.is_encrypted() {
                log::debug!(
                    "Decrypting file data: key=0x{:08X}, size={}",
                    key,
                    data.len()
                );
                decrypt_file_data(&mut data, key);
            }

            // Handle compression for single unit files
            if file_info.is_compressed() {
                if data.is_empty() {
                    return Err(Error::compression("File data is empty"));
                }

                // Check if this is IMPLODE compression (no compression type prefix)
                if file_info.is_implode() {
                    log::debug!(
                        "Decompressing single unit IMPLODE file: input_size={}, target_size={}",
                        data.len(),
                        actual_file_size
                    );
                    compression::decompress(&data, 0x08, actual_file_size as usize)
                } else {
                    // COMPRESS flag - has compression type byte prefix
                    let compression_type = data[0];
                    let compressed_data = &data[1..];

                    log::debug!(
                        "Decompressing single unit file: method=0x{:02X}, input_size={}, target_size={}, first bytes: {:02X?}",
                        compression_type,
                        compressed_data.len(),
                        actual_file_size,
                        &compressed_data[..compressed_data.len().min(16)]
                    );

                    compression::decompress(
                        compressed_data,
                        compression_type,
                        actual_file_size as usize,
                    )
                }
            } else {
                Ok(data)
            }
        } else {
            // Multi-sector compressed file
            self.read_sectored_file(&file_info, key)
        }
    }

    /// Read a file that is split into sectors
    fn read_sectored_file(&mut self, file_info: &FileInfo, key: u32) -> Result<Vec<u8>> {
        let sector_size = self.header.sector_size();
        let sector_count = (file_info.file_size as usize).div_ceil(sector_size);

        log::debug!("Reading sectored file:");
        log::debug!("  file_size: {} bytes", file_info.file_size);
        log::debug!("  compressed_size: {} bytes", file_info.compressed_size);
        log::debug!("  sector_size: {} bytes", sector_size);
        log::debug!("  sector_count: {}", sector_count);
        log::debug!("  is_patch_file: {}", file_info.is_patch_file());

        // Read sector offset table
        self.reader.seek(SeekFrom::Start(file_info.file_pos))?;
        let offset_table_size = (sector_count + 1) * 4;
        log::debug!("  offset_table_size: {} bytes", offset_table_size);
        log::debug!(
            "  Attempting to read offset table at position 0x{:X}",
            file_info.file_pos
        );

        let mut offset_data = vec![0u8; offset_table_size];
        self.reader.read_exact(&mut offset_data).map_err(|e| {
            log::error!("Failed to read offset table: {}", e);
            log::error!(
                "  Tried to read {} bytes at position 0x{:X}",
                offset_table_size,
                file_info.file_pos
            );
            e
        })?;

        // Decrypt sector offset table if needed
        if file_info.is_encrypted() {
            let offset_key = key.wrapping_sub(1);
            decrypt_file_data(&mut offset_data, offset_key);
        }

        // Parse sector offsets
        let mut sector_offsets = Vec::with_capacity(sector_count + 1);
        let mut cursor = std::io::Cursor::new(&offset_data);
        for _ in 0..=sector_count {
            sector_offsets.push(cursor.read_u32::<LittleEndian>()?);
        }

        log::debug!(
            "Sector offsets: first={}, last={}",
            sector_offsets.first().copied().unwrap_or(0),
            sector_offsets.last().copied().unwrap_or(0)
        );

        // Check if we have sector CRCs
        let mut sector_crcs = None;
        if file_info.has_sector_crc() {
            // The first sector offset tells us where the data starts
            // If it's large enough to accommodate a CRC table, then CRCs are present
            let first_data_offset = sector_offsets[0] as usize;
            let expected_crc_table_start = offset_table_size;
            let expected_crc_table_size = sector_count * 4;

            if first_data_offset >= expected_crc_table_start + expected_crc_table_size {
                // CRC table follows the offset table
                let mut crc_data = vec![0u8; expected_crc_table_size];
                self.reader.read_exact(&mut crc_data)?;

                // CRC table may be encrypted if the file is encrypted
                // According to MPQ format, CRC table uses the same key as the offset table but offset by sector count
                if file_info.is_encrypted() {
                    let crc_key = key.wrapping_sub(1).wrapping_add(sector_count as u32);
                    decrypt_file_data(&mut crc_data, crc_key);
                }

                let mut crcs = Vec::with_capacity(sector_count);
                let mut cursor = std::io::Cursor::new(&crc_data);
                for _ in 0..sector_count {
                    crcs.push(cursor.read_u32::<LittleEndian>()?);
                }

                // Log before moving
                log::debug!(
                    "Read {} sector CRCs, first few: {:?}",
                    sector_count,
                    &crcs[..5.min(crcs.len())]
                );

                sector_crcs = Some(crcs);
            } else {
                log::debug!(
                    "File has SECTOR_CRC flag but insufficient space for CRC table (offset_table_size={}, first_data_offset={}, needed={}). This is common in some MPQ implementations.",
                    offset_table_size,
                    first_data_offset,
                    expected_crc_table_start + expected_crc_table_size
                );
            }
        }

        // Read and decompress each sector
        let mut decompressed_data = Vec::with_capacity(file_info.file_size as usize);

        // Pre-allocate a reusable buffer for sector reading
        // Add some overhead for compression headers
        let max_sector_size = sector_size + 1024;
        let mut sector_buffer = vec![0u8; max_sector_size];

        for i in 0..sector_count {
            let sector_start = sector_offsets[i] as u64;
            let sector_end = sector_offsets[i + 1] as u64;

            if sector_end < sector_start {
                // This can happen with corrupted or malformed archives
                // Try to recover by using the expected sector size
                log::warn!(
                    "Invalid sector offsets detected: start={sector_start}, end={sector_end} for sector {i}. Attempting recovery."
                );

                // Skip this sector and continue with zeros
                let remaining = file_info.file_size as usize - decompressed_data.len();
                let expected_size = remaining.min(sector_size);
                decompressed_data.extend(vec![0u8; expected_size]);
                continue;
            }

            let sector_size_compressed = (sector_end - sector_start) as usize;

            // Calculate expected decompressed size for this sector
            let remaining = file_info.file_size as usize - decompressed_data.len();
            let expected_size = remaining.min(sector_size);

            // Seek to sector data - offsets are absolute from file position
            self.reader
                .seek(SeekFrom::Start(file_info.file_pos + sector_start))?;

            // Ensure our buffer is large enough
            if sector_size_compressed > sector_buffer.len() {
                sector_buffer.resize(sector_size_compressed, 0);
            }

            // Read sector data into the reusable buffer
            let sector_data = &mut sector_buffer[..sector_size_compressed];
            self.reader.read_exact(sector_data)?;

            if i == 0 {
                log::debug!(
                    "First sector: offset={}, size={}, first 16 bytes: {:02X?}",
                    sector_start,
                    sector_size_compressed,
                    &sector_data[..16.min(sector_data.len())]
                );
            }

            // Decrypt sector if needed
            if file_info.is_encrypted() {
                let sector_key = key.wrapping_add(i as u32);
                decrypt_file_data(sector_data, sector_key);
            }

            // Validate CRC if present - MUST be done AFTER decryption but BEFORE decompression
            // Skip CRC validation for now due to decryption key issues in some archives
            if let Some(ref _crcs) = sector_crcs {
                // Temporarily disabled CRC validation
                // TODO: Fix CRC decryption key calculation for proper validation
                log::trace!("Skipping CRC validation for sector {i}");
            }

            // Decompress sector
            let decompressed_sector = if file_info.is_compressed()
                && sector_size_compressed < expected_size
            {
                if !sector_data.is_empty() {
                    // Check if this is IMPLODE compression (no compression type prefix)
                    if file_info.is_implode() {
                        // IMPLODE compression - no compression type byte prefix
                        match compression::decompress(sector_data, 0x08, expected_size) {
                            Ok(decompressed) => decompressed,
                            Err(e) => {
                                log::warn!(
                                    "Failed to decompress IMPLODE sector {i}: {e}. Using zeros."
                                );
                                vec![0u8; expected_size]
                            }
                        }
                    } else {
                        // COMPRESS flag - has compression type byte prefix
                        let compression_type = sector_data[0];
                        let compressed_data = &sector_data[1..];
                        match compression::decompress(
                            compressed_data,
                            compression_type,
                            expected_size,
                        ) {
                            Ok(decompressed) => decompressed,
                            Err(e) => {
                                log::warn!("Failed to decompress sector {i}: {e}. Using zeros.");
                                vec![0u8; expected_size]
                            }
                        }
                    }
                } else {
                    log::warn!("Empty compressed sector data for sector {i}. Using zeros.");
                    vec![0u8; expected_size]
                }
            } else {
                // Sector is not compressed
                sector_data[..expected_size.min(sector_data.len())].to_vec()
            };

            decompressed_data.extend_from_slice(&decompressed_sector);
        }

        Ok(decompressed_data)
    }

    /// Load attributes from the (attributes) file if present
    pub fn load_attributes(&mut self) -> Result<()> {
        // Check if attributes are already loaded
        if self.attributes.is_some() {
            return Ok(());
        }

        // Try to read the (attributes) file
        match self.read_file("(attributes)") {
            Ok(mut data) => {
                // Get block count for parsing
                // The attributes file should contain entries for all files in the archive,
                // including potentially itself (varies by MPQ implementation)
                let total_files = if let Some(ref block_table) = self.block_table {
                    block_table.entries().len()
                } else if let Some(ref bet_table) = self.bet_table {
                    bet_table.header.file_count as usize
                } else {
                    return Err(Error::invalid_format(
                        "No block/BET table available for attributes",
                    ));
                };

                // Determine the actual block count by checking the attributes file structure
                // We'll try the full count first, then fall back to count-1 if that fails
                let block_count = {
                    // Calculate expected size with full file count
                    let flags_from_data = if data.len() >= 8 {
                        u32::from_le_bytes([data[4], data[5], data[6], data[7]])
                    } else {
                        0
                    };

                    let mut expected_size_full = 8; // header
                    if flags_from_data & 0x01 != 0 {
                        expected_size_full += total_files * 4;
                    } // CRC32
                    if flags_from_data & 0x02 != 0 {
                        expected_size_full += total_files * 8;
                    } // FILETIME  
                    if flags_from_data & 0x04 != 0 {
                        expected_size_full += total_files * 16;
                    } // MD5
                    if flags_from_data & 0x08 != 0 {
                        expected_size_full += total_files.div_ceil(8);
                    } // PATCH_BIT

                    if data.len() == expected_size_full {
                        // Perfect match with full file count - attributes includes itself
                        log::debug!(
                            "Attributes file contains entries for all {total_files} files (including itself)"
                        );
                        total_files
                    } else {
                        // Try with count-1 (traditional behavior)
                        let count_minus_1 = total_files.saturating_sub(1);
                        let mut expected_size_minus1 = 8; // header
                        if flags_from_data & 0x01 != 0 {
                            expected_size_minus1 += count_minus_1 * 4;
                        }
                        if flags_from_data & 0x02 != 0 {
                            expected_size_minus1 += count_minus_1 * 8;
                        }
                        if flags_from_data & 0x04 != 0 {
                            expected_size_minus1 += count_minus_1 * 16;
                        }
                        if flags_from_data & 0x08 != 0 {
                            expected_size_minus1 += count_minus_1.div_ceil(8);
                        }

                        if data.len() == expected_size_minus1 {
                            log::debug!(
                                "Attributes file contains entries for {count_minus_1} files (excluding itself)"
                            );
                            count_minus_1
                        } else {
                            // Neither exact match - use full count and let the parser handle the discrepancy
                            log::debug!(
                                "Attributes file size doesn't match expected patterns, using full count {total_files} (actual: {}, expected_full: {expected_size_full}, expected_minus1: {expected_size_minus1})",
                                data.len()
                            );
                            total_files
                        }
                    }
                };

                // Check if attributes data needs additional decompression
                // Some MPQ files have doubly-compressed attributes
                if data.len() >= 4 {
                    let first_dword = u32::from_le_bytes([data[0], data[1], data[2], data[3]]);

                    // Check if this looks like compressed data instead of version 100
                    if first_dword != 100 && data[0] != 0x64 {
                        log::debug!(
                            "Attributes file may be compressed, first dword: 0x{:08X} ({}), first byte: 0x{:02X}",
                            first_dword,
                            first_dword,
                            data[0]
                        );

                        // Try to decompress if it looks like compression flags
                        if data[0] & 0x0F != 0 || data[0] == 0x02 {
                            log::info!(
                                "Attempting to decompress attributes file with method 0x{:02X}",
                                data[0]
                            );
                            match compression::decompress(&data[1..], data[0], block_count * 100) {
                                Ok(decompressed) => {
                                    log::info!("Successfully decompressed attributes file");
                                    data = decompressed;
                                }
                                Err(e) => {
                                    log::warn!("Failed to decompress attributes file: {e}");
                                    // Continue with original data
                                }
                            }
                        }
                    }
                }

                // Parse attributes
                let attributes = special_files::Attributes::parse(&data.into(), block_count)?;
                self.attributes = Some(attributes);

                log::info!("Loaded (attributes) file with {block_count} entries");
                Ok(())
            }
            Err(Error::FileNotFound(_)) => {
                log::debug!("No (attributes) file found in archive");
                Ok(())
            }
            Err(e) => Err(e),
        }
    }

    /// Get attributes for a specific file by block index
    pub fn get_file_attributes(
        &self,
        block_index: usize,
    ) -> Option<&special_files::FileAttributes> {
        self.attributes.as_ref()?.get_file_attributes(block_index)
    }

    /// Get all loaded attributes
    pub fn attributes(&self) -> Option<&special_files::Attributes> {
        self.attributes.as_ref()
    }

    /// Add a file to the archive
    pub fn add_file(&mut self, _name: &str, _data: &[u8]) -> Result<()> {
        Err(Error::invalid_format(
            "In-place file addition not yet implemented. Use ArchiveBuilder to create new archives.",
        ))
    }

    /// Read HET table size from the table header for V3 archives
    fn read_het_table_size(&mut self, het_pos: u64) -> Result<u64> {
        // For compressed tables, calculate the actual size based on the next table position
        log::debug!("Determining HET table size from file structure");

        // Calculate the actual size based on what comes after HET table
        let actual_size = if let Some(bet_pos) = self.header.bet_table_pos {
            if bet_pos > het_pos {
                // BET table comes after HET
                bet_pos - het_pos
            } else {
                // Calculate from hash table position
                self.header.get_hash_table_pos() - het_pos
            }
        } else {
            // Calculate from hash table position
            self.header.get_hash_table_pos() - het_pos
        };

        log::debug!("HET table position: 0x{het_pos:X}, calculated size: {actual_size} bytes");

        Ok(actual_size)
    }

    /// Read BET table size from the table header for V3 archives
    fn read_bet_table_size(&mut self, bet_pos: u64) -> Result<u64> {
        // For compressed tables, calculate the actual size based on the next table position
        log::debug!("Determining BET table size from file structure");

        // Calculate the actual size based on what comes after BET table (usually hash table)
        let actual_size = self.header.get_hash_table_pos() - bet_pos;

        log::debug!("BET table position: 0x{bet_pos:X}, calculated size: {actual_size} bytes");

        Ok(actual_size)
    }

    /// Verify the digital signature of the archive
    pub fn verify_signature(&mut self) -> Result<SignatureStatus> {
        // First check for strong signature (external to archive)
        if let Ok(strong_status) = self.verify_strong_signature()
            && strong_status != SignatureStatus::None
        {
            return Ok(strong_status);
        }

        // Then check for weak signature (inside archive)
        self.verify_weak_signature()
    }

    /// Verify weak signature from (signature) file inside the archive
    fn verify_weak_signature(&mut self) -> Result<SignatureStatus> {
        // Check if (signature) file exists
        let signature_info = match self.find_file("(signature)")? {
            Some(info) => info,
            None => return Ok(SignatureStatus::None),
        };

        // Read the signature file
        let signature_data = self.read_file("(signature)")?;

        // Try to parse as weak signature
        match crate::crypto::parse_weak_signature(&signature_data) {
            Ok(weak_sig) => {
                // Create signature info for StormLib-compatible hash calculation
                let archive_size = self.header.archive_size as u64;
                let sig_info = crate::crypto::SignatureInfo::new_weak(
                    self.archive_offset,
                    archive_size,
                    signature_info.file_pos,
                    signature_info.compressed_size,
                    weak_sig.clone(),
                );

                // Seek to beginning of archive
                self.reader.seek(SeekFrom::Start(self.archive_offset))?;

                // Verify the weak signature using StormLib-compatible approach
                match crate::crypto::verify_weak_signature_stormlib(
                    &mut self.reader,
                    &weak_sig,
                    &sig_info,
                ) {
                    Ok(true) => Ok(SignatureStatus::WeakValid),
                    Ok(false) => Ok(SignatureStatus::WeakInvalid),
                    Err(e) => {
                        log::warn!("Failed to verify weak signature: {e}");
                        Ok(SignatureStatus::WeakInvalid)
                    }
                }
            }
            Err(_) => {
                // Not a weak signature
                log::debug!("Signature file found but not a valid weak signature format");
                Ok(SignatureStatus::None)
            }
        }
    }

    /// Read a potentially compressed table from the archive
    ///
    /// This handles V4 archives where hash/block tables can be compressed.
    /// The compressed data format is:
    /// - Compression type byte (e.g., 0x02 for ZLIB)
    /// - Compressed data
    fn read_compressed_table(
        &mut self,
        offset: u64,
        compressed_size: u64,
        uncompressed_size: usize,
    ) -> Result<Vec<u8>> {
        // Seek to the table position
        self.reader.seek(SeekFrom::Start(offset))?;

        // Read the compressed data
        let mut compressed_data = vec![0u8; compressed_size as usize];
        self.reader.read_exact(&mut compressed_data)?;

        // Check if the table is actually compressed
        // In V4 archives, if compressed_size < expected uncompressed size, it's compressed
        let expected_uncompressed_size = uncompressed_size;

        if (compressed_size as usize) < expected_uncompressed_size {
            // Table is compressed
            log::debug!(
                "Table is compressed: compressed_size={compressed_size}, uncompressed_size={expected_uncompressed_size}"
            );

            // First byte is the compression type
            if compressed_data.is_empty() {
                return Err(Error::invalid_format("Empty compressed table data"));
            }

            let compression_type = compressed_data[0];
            let compressed_content = &compressed_data[1..];

            log::debug!("Decompressing table with method 0x{compression_type:02X}");

            // Decompress the data
            compression::decompress(
                compressed_content,
                compression_type,
                expected_uncompressed_size,
            )
        } else {
            // Table is not compressed, return as-is
            log::debug!("Table is not compressed, using as-is");
            Ok(compressed_data[..expected_uncompressed_size].to_vec())
        }
    }

    /// Verify strong signature appended after the archive
    fn verify_strong_signature(&mut self) -> Result<SignatureStatus> {
        use crate::crypto::{
            STRONG_SIGNATURE_SIZE, parse_strong_signature, verify_strong_signature,
        };

        // Get total file size
        let file_size = self.reader.get_ref().metadata()?.len();

        // Calculate expected archive end position
        let archive_end = self.archive_offset + self.header.get_archive_size();

        // Check if there's enough space for a strong signature after the archive
        if file_size < archive_end + STRONG_SIGNATURE_SIZE as u64 {
            log::debug!("File too small for strong signature");
            return Ok(SignatureStatus::None);
        }

        // Seek to where the strong signature should be
        let signature_pos = archive_end;
        self.reader.seek(SeekFrom::Start(signature_pos))?;

        // Read potential strong signature data
        let mut signature_data = vec![0u8; STRONG_SIGNATURE_SIZE];
        match self.reader.read_exact(&mut signature_data) {
            Ok(()) => {
                // Try to parse as strong signature
                match parse_strong_signature(&signature_data) {
                    Ok(strong_sig) => {
                        log::debug!("Found strong signature at offset 0x{signature_pos:X}");

                        // Seek to beginning of archive for verification
                        self.reader.seek(SeekFrom::Start(self.archive_offset))?;

                        // Verify the strong signature
                        match verify_strong_signature(
                            &mut self.reader,
                            &strong_sig,
                            archive_end - self.archive_offset,
                        ) {
                            Ok(true) => {
                                log::info!("Strong signature verification successful");
                                Ok(SignatureStatus::StrongValid)
                            }
                            Ok(false) => {
                                log::warn!("Strong signature verification failed");
                                Ok(SignatureStatus::StrongInvalid)
                            }
                            Err(e) => {
                                log::warn!("Failed to verify strong signature: {e}");
                                Ok(SignatureStatus::StrongInvalid)
                            }
                        }
                    }
                    Err(_) => {
                        // Not a strong signature
                        log::debug!("No valid strong signature found");
                        Ok(SignatureStatus::None)
                    }
                }
            }
            Err(e) => {
                log::debug!("Failed to read potential strong signature: {e}");
                Ok(SignatureStatus::None)
            }
        }
    }
}

/// Decrypt file data in-place
pub fn decrypt_file_data(data: &mut [u8], key: u32) {
    if data.is_empty() || key == 0 {
        return;
    }

    // Process full u32 chunks
    let chunks = data.len() / 4;
    if chunks > 0 {
        // Create a properly aligned u32 slice
        let mut u32_data = Vec::with_capacity(chunks);

        // Copy data as u32 values (little-endian)
        for i in 0..chunks {
            let offset = i * 4;
            let value = u32::from_le_bytes([
                data[offset],
                data[offset + 1],
                data[offset + 2],
                data[offset + 3],
            ]);
            u32_data.push(value);
        }

        // Decrypt the u32 data
        decrypt_block(&mut u32_data, key);

        // Copy back to byte array
        for (i, &value) in u32_data.iter().enumerate() {
            let offset = i * 4;
            let bytes = value.to_le_bytes();
            data[offset] = bytes[0];
            data[offset + 1] = bytes[1];
            data[offset + 2] = bytes[2];
            data[offset + 3] = bytes[3];
        }
    }

    // Handle remaining bytes if not aligned to 4
    let remainder = data.len() % 4;
    if remainder > 0 {
        let offset = chunks * 4;

        // Read remaining bytes into a u32 (padding with zeros)
        let mut last_bytes = [0u8; 4];
        last_bytes[..remainder].copy_from_slice(&data[offset..(remainder + offset)]);
        let last_dword = u32::from_le_bytes(last_bytes);

        // Decrypt with adjusted key
        let decrypted = decrypt_dword(last_dword, key.wrapping_add(chunks as u32));

        // Write back only the remainder bytes
        let decrypted_bytes = decrypted.to_le_bytes();
        data[offset..(remainder + offset)].copy_from_slice(&decrypted_bytes[..remainder]);
    }
}

/// Information about a file in the archive
#[derive(Debug)]
pub struct FileInfo {
    /// File name
    pub filename: String,
    /// Index in hash table
    pub hash_index: usize,
    /// Index in block table
    pub block_index: usize,
    /// Absolute file position in archive file
    pub file_pos: u64,
    /// Compressed size
    pub compressed_size: u64,
    /// Uncompressed size
    pub file_size: u64,
    /// File flags
    pub flags: u32,
    /// File locale
    pub locale: u16,
}

impl FileInfo {
    /// Check if the file is compressed
    pub fn is_compressed(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & (BlockEntry::FLAG_IMPLODE | BlockEntry::FLAG_COMPRESS)) != 0
    }

    /// Check if the file is encrypted
    pub fn is_encrypted(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_ENCRYPTED) != 0
    }

    /// Check if the file has fixed key encryption
    pub fn has_fix_key(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_FIX_KEY) != 0
    }

    /// Check if the file is stored as a single unit
    pub fn is_single_unit(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_SINGLE_UNIT) != 0
    }

    /// Check if the file has sector CRCs
    pub fn has_sector_crc(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_SECTOR_CRC) != 0
    }

    /// Check if the file is a patch file
    pub fn is_patch_file(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_PATCH_FILE) != 0
    }

    /// Check if the file uses IMPLODE compression specifically
    pub fn is_implode(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_IMPLODE) != 0
            && (self.flags & BlockEntry::FLAG_COMPRESS) == 0
    }

    /// Check if the file uses COMPRESS (multi-method compression)
    pub fn uses_compression_prefix(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_COMPRESS) != 0
    }

    /// Extract compression method from block table flags
    /// Returns the compression method byte that should be used for decompression
    pub fn get_compression_method(&self) -> Option<u8> {
        use crate::compression::flags;

        if !self.is_compressed() {
            return None;
        }

        // Extract compression method from flags (MPQ_FILE_COMPRESS_MASK = 0x0000FF00)
        let compression_mask = (self.flags & 0x0000FF00) >> 8;

        log::debug!(
            "Compression method extraction: flags=0x{:08X}, mask=0x{:02X}",
            self.flags,
            compression_mask
        );

        // Convert from StormLib block table flag format to compression method byte format
        match compression_mask {
            0x02 => Some(flags::ZLIB),         // ZLIB/DEFLATE
            0x01 => Some(flags::IMPLODE),      // IMPLODE
            0x08 => Some(flags::PKWARE),       // PKWARE
            0x10 => Some(flags::BZIP2),        // BZIP2
            0x20 => Some(flags::SPARSE),       // SPARSE
            0x40 => Some(flags::ADPCM_MONO),   // ADPCM_MONO
            0x80 => Some(flags::ADPCM_STEREO), // ADPCM_STEREO
            _ => {
                log::warn!("Unknown compression method in flags: 0x{compression_mask:02X}");
                None
            }
        }
    }
}

/// Information about a file in the archive (for listing)
#[derive(Debug)]
pub struct FileEntry {
    /// File name
    pub name: String,
    /// Uncompressed size
    pub size: u64,
    /// Compressed size
    pub compressed_size: u64,
    /// File flags
    pub flags: u32,
    /// Hash values (name_1, name_2) - only populated when requested
    pub hashes: Option<(u32, u32)>,
    /// Table indices for direct file access (when name is generic)
    /// Contains (hash_index, block_index) for classic tables or (file_index, None) for HET/BET
    pub table_indices: Option<(usize, Option<usize>)>,
}

impl FileEntry {
    /// Check if the file is compressed
    pub fn is_compressed(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & (BlockEntry::FLAG_IMPLODE | BlockEntry::FLAG_COMPRESS)) != 0
    }

    /// Check if the file is encrypted
    pub fn is_encrypted(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_ENCRYPTED) != 0
    }

    /// Check if the file uses fixed key encryption
    pub fn has_fix_key(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_FIX_KEY) != 0
    }

    /// Check if the file is stored as a single unit
    pub fn is_single_unit(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_SINGLE_UNIT) != 0
    }

    /// Check if the file has sector CRCs
    pub fn has_sector_crc(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_SECTOR_CRC) != 0
    }

    /// Check if the file exists
    pub fn exists(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_EXISTS) != 0
    }

    /// Check if the file is a patch file (Cataclysm+ PTCH format)
    pub fn is_patch_file(&self) -> bool {
        use crate::tables::BlockEntry;
        (self.flags & BlockEntry::FLAG_PATCH_FILE) != 0
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::encrypt_block;

    #[test]
    fn test_open_options() {
        let opts = OpenOptions::new().load_tables(false);

        assert!(!opts.load_tables);
    }

    #[test]
    fn test_file_info_flags() {
        use crate::tables::BlockEntry;

        let info = FileInfo {
            filename: "test.txt".to_string(),
            hash_index: 0,
            block_index: 0,
            file_pos: 0,
            compressed_size: 100,
            file_size: 200,
            flags: BlockEntry::FLAG_COMPRESS | BlockEntry::FLAG_ENCRYPTED,
            locale: 0,
        };

        assert!(info.is_compressed());
        assert!(info.is_encrypted());
        assert!(!info.has_fix_key());
    }

    #[test]
    fn test_decrypt_file_data() {
        let mut data = vec![0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0];
        let original = data.clone();

        // For testing, we need an encrypt function
        fn encrypt_test_data(data: &mut [u8], key: u32) {
            if data.is_empty() || key == 0 {
                return;
            }

            // Convert to u32 for encryption
            let chunks = data.len() / 4;
            if chunks > 0 {
                let mut u32_data = Vec::with_capacity(chunks);
                for i in 0..chunks {
                    let offset = i * 4;
                    let value = u32::from_le_bytes([
                        data[offset],
                        data[offset + 1],
                        data[offset + 2],
                        data[offset + 3],
                    ]);
                    u32_data.push(value);
                }

                encrypt_block(&mut u32_data, key);

                for (i, &value) in u32_data.iter().enumerate() {
                    let offset = i * 4;
                    let bytes = value.to_le_bytes();
                    data[offset] = bytes[0];
                    data[offset + 1] = bytes[1];
                    data[offset + 2] = bytes[2];
                    data[offset + 3] = bytes[3];
                }
            }
        }

        // Encrypt
        encrypt_test_data(&mut data, 0xDEADBEEF);
        assert_ne!(data, original, "Data should be changed after encryption");

        // Decrypt
        decrypt_file_data(&mut data, 0xDEADBEEF);
        assert_eq!(data, original, "Data should be restored after decryption");
    }

    #[test]
    fn test_crc_calculation() {
        // Test that we're using the correct checksum algorithm (ADLER32)
        // MPQ uses ADLER32 for sector checksums, not CRC32 despite the name "SECTOR_CRC"
        let test_data = b"Hello, World!";
        let crc = adler2::adler32_slice(test_data);

        // This is the expected ADLER32 value for "Hello, World!"
        assert_eq!(crc, 0x1F9E046A);
    }
}