voirs-cli 0.1.0-beta.1

// Cloud storage integration for VoiRS model and data synchronization
use aes_gcm::{
    aead::{Aead, KeyInit, OsRng},
    Aes256Gcm, Nonce,
};
use anyhow::Result;
use serde::{Deserialize, Serialize};
use sha2::{Digest, Sha256};
use std::collections::HashMap;
use std::path::{Path, PathBuf};
use tokio::fs;

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CloudStorageConfig {
    pub provider: StorageProvider,
    pub bucket_name: String,
    pub region: String,
    pub access_key: Option<String>,
    pub secret_key: Option<String>,
    pub endpoint: Option<String>,
    pub encryption_enabled: bool,
    pub compression_enabled: bool,
    pub sync_interval_seconds: u64,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum StorageProvider {
    AWS,
    Azure,
    GoogleCloud,
    MinIO,
    S3Compatible,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct SyncableItem {
    pub local_path: PathBuf,
    pub remote_path: String,
    pub last_modified: u64,
    pub checksum: String,
    pub size_bytes: u64,
    pub sync_priority: SyncPriority,
    pub sync_direction: SyncDirection,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum SyncPriority {
    Low,
    Normal,
    High,
    Critical,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum SyncDirection {
    Upload,
    Download,
    Bidirectional,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct SyncManifest {
    pub version: u32,
    pub last_sync_timestamp: u64,
    pub items: Vec<SyncableItem>,
    pub total_size_bytes: u64,
    pub checksum: String,
}

pub struct CloudStorageManager {
    config: CloudStorageConfig,
    local_cache_dir: PathBuf,
    sync_manifest: SyncManifest,
    pending_uploads: Vec<SyncableItem>,
    pending_downloads: Vec<SyncableItem>,
}

impl CloudStorageManager {
    pub fn new(config: CloudStorageConfig, cache_dir: PathBuf) -> Result<Self> {
        std::fs::create_dir_all(&cache_dir)?;

        let manifest_path = cache_dir.join("sync_manifest.json");
        let sync_manifest = if manifest_path.exists() {
            let content = std::fs::read_to_string(&manifest_path)?;
            serde_json::from_str(&content)?
        } else {
            SyncManifest::new()
        };

        Ok(Self {
            config,
            local_cache_dir: cache_dir,
            sync_manifest,
            pending_uploads: Vec::new(),
            pending_downloads: Vec::new(),
        })
    }

    /// Add a file or directory to the synchronization list
    pub async fn add_to_sync(
        &mut self,
        local_path: PathBuf,
        remote_path: String,
        direction: SyncDirection,
    ) -> Result<()> {
        let metadata = fs::metadata(&local_path).await?;
        let last_modified = metadata
            .modified()?
            .duration_since(std::time::UNIX_EPOCH)?
            .as_secs();

        let checksum = self.calculate_file_checksum(&local_path).await?;

        let item = SyncableItem {
            local_path,
            remote_path,
            last_modified,
            checksum,
            size_bytes: metadata.len(),
            sync_priority: SyncPriority::Normal,
            sync_direction: direction,
        };

        self.sync_manifest.items.push(item);
        self.save_manifest().await?;

        Ok(())
    }

    /// Perform synchronization based on the current manifest
    pub async fn sync(&mut self) -> Result<SyncResult> {
        let mut result = SyncResult::new();

        // Process all items in the manifest
        for item in &self.sync_manifest.items {
            match item.sync_direction {
                SyncDirection::Upload => {
                    if self.should_upload(item).await? {
                        match self.upload_file(item).await {
                            Ok(_) => result.uploaded_files += 1,
                            Err(e) => {
                                result.failed_uploads += 1;
                                result.errors.push(format!(
                                    "Upload failed for {}: {}",
                                    item.local_path.display(),
                                    e
                                ));
                            }
                        }
                    }
                }
                SyncDirection::Download => {
                    if self.should_download(item).await? {
                        match self.download_file(item).await {
                            Ok(_) => result.downloaded_files += 1,
                            Err(e) => {
                                result.failed_downloads += 1;
                                result.errors.push(format!(
                                    "Download failed for {}: {}",
                                    item.remote_path, e
                                ));
                            }
                        }
                    }
                }
                SyncDirection::Bidirectional => {
                    // Determine sync direction based on timestamps
                    let sync_direction = self.determine_sync_direction(item).await?;
                    match sync_direction {
                        Some(SyncDirection::Upload) => match self.upload_file(item).await {
                            Ok(_) => result.uploaded_files += 1,
                            Err(e) => {
                                result.failed_uploads += 1;
                                result.errors.push(format!(
                                    "Upload failed for {}: {}",
                                    item.local_path.display(),
                                    e
                                ));
                            }
                        },
                        Some(SyncDirection::Download) => match self.download_file(item).await {
                            Ok(_) => result.downloaded_files += 1,
                            Err(e) => {
                                result.failed_downloads += 1;
                                result.errors.push(format!(
                                    "Download failed for {}: {}",
                                    item.remote_path, e
                                ));
                            }
                        },
                        _ => {
                            // Files are in sync, no action needed
                            result.skipped_files += 1;
                        }
                    }
                }
            }
        }

        // Update sync timestamp
        self.sync_manifest.last_sync_timestamp = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_secs();

        self.save_manifest().await?;

        Ok(result)
    }

    /// Upload a specific file to cloud storage
    async fn upload_file(&self, item: &SyncableItem) -> Result<()> {
        tracing::info!(
            "Uploading {} to {}",
            item.local_path.display(),
            item.remote_path
        );

        // Validate that the local file exists
        if !item.local_path.exists() {
            return Err(anyhow::anyhow!(
                "Local file does not exist: {}",
                item.local_path.display()
            ));
        }

        // Read the file content
        let file_content = fs::read(&item.local_path).await?;

        // Verify file integrity using checksum
        let file_checksum = calculate_file_checksum(&file_content);
        if file_checksum != item.checksum {
            return Err(anyhow::anyhow!("File checksum mismatch during upload"));
        }

        // Compress the file if compression is enabled
        let upload_content = if self.config.compression_enabled {
            self.compress_data(&file_content).await?
        } else {
            file_content
        };

        // Encrypt the file if encryption is enabled
        let final_content = if self.config.encryption_enabled {
            self.encrypt_data(&upload_content).await?
        } else {
            upload_content
        };

        // Perform the actual upload based on provider
        match self.config.provider {
            StorageProvider::AWS => {
                self.upload_to_aws(&item.remote_path, &final_content)
                    .await?
            }
            StorageProvider::Azure => {
                self.upload_to_azure(&item.remote_path, &final_content)
                    .await?
            }
            StorageProvider::GoogleCloud => {
                self.upload_to_gcp(&item.remote_path, &final_content)
                    .await?
            }
            StorageProvider::MinIO | StorageProvider::S3Compatible => {
                self.upload_to_s3_compatible(&item.remote_path, &final_content)
                    .await?
            }
        }

        tracing::info!(
            "Successfully uploaded {} ({} bytes) to {}",
            item.local_path.display(),
            item.size_bytes,
            item.remote_path
        );

        Ok(())
    }

    /// Download a specific file from cloud storage
    async fn download_file(&self, item: &SyncableItem) -> Result<()> {
        tracing::info!(
            "Downloading {} to {}",
            item.remote_path,
            item.local_path.display()
        );

        // Ensure local directory exists
        if let Some(parent) = item.local_path.parent() {
            fs::create_dir_all(parent).await?;
        }

        // Download the file content based on provider
        let downloaded_content = match self.config.provider {
            StorageProvider::AWS => self.download_from_aws(&item.remote_path).await?,
            StorageProvider::Azure => self.download_from_azure(&item.remote_path).await?,
            StorageProvider::GoogleCloud => self.download_from_gcp(&item.remote_path).await?,
            StorageProvider::MinIO | StorageProvider::S3Compatible => {
                self.download_from_s3_compatible(&item.remote_path).await?
            }
        };

        // Decrypt the file if encryption is enabled
        let decrypted_content = if self.config.encryption_enabled {
            self.decrypt_data(&downloaded_content).await?
        } else {
            downloaded_content
        };

        // Decompress the file if compression is enabled
        let final_content = if self.config.compression_enabled {
            self.decompress_data(&decrypted_content).await?
        } else {
            decrypted_content
        };

        // Verify file integrity using checksum
        let file_checksum = calculate_file_checksum(&final_content);
        if file_checksum != item.checksum {
            return Err(anyhow::anyhow!("File checksum mismatch during download"));
        }

        // Write the file to local storage
        fs::write(&item.local_path, &final_content).await?;

        // Update file metadata to match the remote version
        let metadata = fs::metadata(&item.local_path).await?;
        if metadata.len() != item.size_bytes {
            return Err(anyhow::anyhow!("Downloaded file size mismatch"));
        }

        tracing::info!(
            "Successfully downloaded {} ({} bytes) to {}",
            item.remote_path,
            item.size_bytes,
            item.local_path.display()
        );

        Ok(())
    }

    /// Check if a file should be uploaded
    async fn should_upload(&self, item: &SyncableItem) -> Result<bool> {
        // Check if local file exists and is newer than last sync
        if !item.local_path.exists() {
            return Ok(false);
        }

        let metadata = fs::metadata(&item.local_path).await?;
        let last_modified = metadata
            .modified()?
            .duration_since(std::time::UNIX_EPOCH)?
            .as_secs();

        // Upload if file was modified since last sync
        Ok(last_modified > self.sync_manifest.last_sync_timestamp)
    }

    /// Check if a file should be downloaded
    async fn should_download(&self, item: &SyncableItem) -> Result<bool> {
        // This would check remote file timestamp
        // For now, we'll just check if local file doesn't exist
        Ok(!item.local_path.exists())
    }

    /// Determine sync direction for bidirectional items
    async fn determine_sync_direction(&self, item: &SyncableItem) -> Result<Option<SyncDirection>> {
        if !item.local_path.exists() {
            return Ok(Some(SyncDirection::Download));
        }

        // In a real implementation, this would compare local and remote timestamps
        // For now, we'll prioritize upload if local file is newer
        let metadata = fs::metadata(&item.local_path).await?;
        let last_modified = metadata
            .modified()?
            .duration_since(std::time::UNIX_EPOCH)?
            .as_secs();

        if last_modified > self.sync_manifest.last_sync_timestamp {
            Ok(Some(SyncDirection::Upload))
        } else {
            Ok(None) // Files are in sync
        }
    }

    /// Calculate SHA256 checksum of a file
    async fn calculate_file_checksum(&self, path: &Path) -> Result<String> {
        let content = fs::read(path).await?;
        let mut hasher = Sha256::new();
        hasher.update(&content);
        let result = hasher.finalize();
        Ok(format!("{:x}", result))
    }

    /// Save the sync manifest to disk
    async fn save_manifest(&self) -> Result<()> {
        let manifest_path = self.local_cache_dir.join("sync_manifest.json");
        let content = serde_json::to_string_pretty(&self.sync_manifest)?;
        fs::write(manifest_path, content).await?;
        Ok(())
    }

    /// Get storage usage statistics
    pub async fn get_storage_stats(&self) -> Result<StorageStats> {
        let total_size: u64 = self
            .sync_manifest
            .items
            .iter()
            .map(|item| item.size_bytes)
            .sum();

        let local_files = self
            .sync_manifest
            .items
            .iter()
            .filter(|item| item.local_path.exists())
            .count();

        Ok(StorageStats {
            total_files: self.sync_manifest.items.len(),
            local_files,
            total_size_bytes: total_size,
            last_sync_timestamp: self.sync_manifest.last_sync_timestamp,
            cache_directory: self.local_cache_dir.clone(),
        })
    }

    /// Cleanup old cache files
    pub async fn cleanup_cache(&mut self, max_age_days: u32) -> Result<CleanupResult> {
        let cutoff_time = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)?
            .as_secs()
            - (max_age_days as u64 * 24 * 60 * 60);

        let mut removed_files = 0;
        let mut freed_bytes = 0u64;
        let mut errors = Vec::new();

        // Remove old items from manifest
        self.sync_manifest.items.retain(|item| {
            if item.last_modified < cutoff_time {
                if item.local_path.exists() {
                    match std::fs::remove_file(&item.local_path) {
                        Ok(_) => {
                            removed_files += 1;
                            freed_bytes += item.size_bytes;
                        }
                        Err(e) => {
                            errors.push(format!(
                                "Failed to remove {}: {}",
                                item.local_path.display(),
                                e
                            ));
                        }
                    }
                }
                false // Remove from manifest
            } else {
                true // Keep in manifest
            }
        });

        self.save_manifest().await?;

        Ok(CleanupResult {
            removed_files,
            freed_bytes,
            errors,
        })
    }

    /// Upload to AWS S3
    async fn upload_to_aws(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        // Implementation for AWS S3 upload using AWS SDK
        // This would use the aws-sdk-s3 crate in a real implementation

        self.create_aws_client().await?;
        let bucket = &self.config.bucket_name;

        // Simulate AWS S3 upload with realistic behavior
        tracing::debug!("Uploading to AWS S3: s3://{}/{}", bucket, remote_path);

        // Create a multipart upload for large files (>5MB)
        if content.len() > 5 * 1024 * 1024 {
            self.aws_multipart_upload(remote_path, content).await?;
        } else {
            self.aws_single_upload(remote_path, content).await?;
        }

        Ok(())
    }

    /// Download from AWS S3
    async fn download_from_aws(&self, remote_path: &str) -> Result<Vec<u8>> {
        self.create_aws_client().await?;
        let bucket = &self.config.bucket_name;

        tracing::debug!("Downloading from AWS S3: s3://{}/{}", bucket, remote_path);

        // Simulate AWS S3 download with realistic behavior
        let content = self.aws_get_object(remote_path).await?;

        Ok(content)
    }

    /// Upload to Azure Blob Storage
    async fn upload_to_azure(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        self.create_azure_client().await?;

        tracing::debug!("Uploading to Azure Blob Storage: {}", remote_path);

        // Simulate Azure Blob Storage upload
        self.azure_put_blob(remote_path, content).await?;

        Ok(())
    }

    /// Download from Azure Blob Storage
    async fn download_from_azure(&self, remote_path: &str) -> Result<Vec<u8>> {
        self.create_azure_client().await?;

        tracing::debug!("Downloading from Azure Blob Storage: {}", remote_path);

        let content = self.azure_get_blob(remote_path).await?;

        Ok(content)
    }

    /// Upload to Google Cloud Storage
    async fn upload_to_gcp(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        self.create_gcp_client().await?;

        tracing::debug!("Uploading to Google Cloud Storage: {}", remote_path);

        self.gcp_upload_object(remote_path, content).await?;

        Ok(())
    }

    /// Download from Google Cloud Storage
    async fn download_from_gcp(&self, remote_path: &str) -> Result<Vec<u8>> {
        self.create_gcp_client().await?;

        tracing::debug!("Downloading from Google Cloud Storage: {}", remote_path);

        let content = self.gcp_download_object(remote_path).await?;

        Ok(content)
    }

    /// Upload to S3-compatible storage (MinIO, etc.)
    async fn upload_to_s3_compatible(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        self.create_s3_compatible_client().await?;

        tracing::debug!("Uploading to S3-compatible storage: {}", remote_path);

        self.s3_compatible_put_object(remote_path, content).await?;

        Ok(())
    }

    /// Download from S3-compatible storage
    async fn download_from_s3_compatible(&self, remote_path: &str) -> Result<Vec<u8>> {
        self.create_s3_compatible_client().await?;

        tracing::debug!("Downloading from S3-compatible storage: {}", remote_path);

        let content = self.s3_compatible_get_object(remote_path).await?;

        Ok(content)
    }

    /// Compress data using gzip
    async fn compress_data(&self, data: &[u8]) -> Result<Vec<u8>> {
        use flate2::write::GzEncoder;
        use flate2::Compression;
        use std::io::Write;

        let mut encoder = GzEncoder::new(Vec::new(), Compression::default());
        encoder.write_all(data)?;
        let compressed = encoder.finish()?;

        tracing::debug!(
            "Compressed {} bytes to {} bytes",
            data.len(),
            compressed.len()
        );

        Ok(compressed)
    }

    /// Decompress data using gzip
    async fn decompress_data(&self, data: &[u8]) -> Result<Vec<u8>> {
        use flate2::read::GzDecoder;
        use std::io::Read;

        let mut decoder = GzDecoder::new(data);
        let mut decompressed = Vec::new();
        decoder.read_to_end(&mut decompressed)?;

        tracing::debug!(
            "Decompressed {} bytes to {} bytes",
            data.len(),
            decompressed.len()
        );

        Ok(decompressed)
    }

    /// Encrypt data using AES-256-GCM
    async fn encrypt_data(&self, data: &[u8]) -> Result<Vec<u8>> {
        use aes_gcm::aead::rand_core::RngCore;

        // Get 256-bit encryption key
        let key = self.get_encryption_key().await?;

        // Ensure key is exactly 32 bytes for AES-256
        let key_bytes: [u8; 32] = if key.len() >= 32 {
            key[..32]
                .try_into()
                .expect("slice of 32 bytes fits into [u8; 32]")
        } else {
            // Derive 32-byte key using SHA-256
            let mut hasher = Sha256::new();
            hasher.update(&key);
            hasher.finalize().into()
        };

        // Create cipher instance
        let cipher = Aes256Gcm::new(&key_bytes.into());

        // Generate random 96-bit nonce (12 bytes)
        let mut nonce_bytes = [0u8; 12];
        OsRng.fill_bytes(&mut nonce_bytes);
        let nonce = Nonce::from_slice(&nonce_bytes);

        // Encrypt data (GCM automatically adds authentication tag)
        let ciphertext = cipher
            .encrypt(nonce, data)
            .map_err(|e| anyhow::anyhow!("AES-GCM encryption failed: {}", e))?;

        // Format: [nonce (12 bytes)] + [ciphertext + tag (16 bytes)]
        let mut encrypted = Vec::with_capacity(12 + ciphertext.len());
        encrypted.extend_from_slice(&nonce_bytes);
        encrypted.extend_from_slice(&ciphertext);

        tracing::debug!(
            "Encrypted {} bytes to {} bytes (including nonce and tag)",
            data.len(),
            encrypted.len()
        );

        Ok(encrypted)
    }

    /// Decrypt data using AES-256-GCM
    async fn decrypt_data(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Ensure we have at least nonce (12 bytes) + tag (16 bytes)
        if data.len() < 28 {
            anyhow::bail!(
                "Invalid encrypted data: too short (need at least 28 bytes, got {})",
                data.len()
            );
        }

        // Get 256-bit encryption key
        let key = self.get_encryption_key().await?;

        // Ensure key is exactly 32 bytes for AES-256
        let key_bytes: [u8; 32] = if key.len() >= 32 {
            key[..32]
                .try_into()
                .expect("slice of 32 bytes fits into [u8; 32]")
        } else {
            // Derive 32-byte key using SHA-256
            let mut hasher = Sha256::new();
            hasher.update(&key);
            hasher.finalize().into()
        };

        // Create cipher instance
        let cipher = Aes256Gcm::new(&key_bytes.into());

        // Extract nonce (first 12 bytes)
        let nonce = Nonce::from_slice(&data[..12]);

        // Extract ciphertext (remaining bytes include authentication tag)
        let ciphertext = &data[12..];

        // Decrypt and verify authentication tag
        let plaintext = cipher
            .decrypt(nonce, ciphertext)
            .map_err(|e| anyhow::anyhow!("AES-GCM decryption failed: {}", e))?;

        tracing::debug!(
            "Decrypted {} bytes to {} bytes",
            data.len(),
            plaintext.len()
        );

        Ok(plaintext)
    }

    /// Get encryption key from configuration or environment
    async fn get_encryption_key(&self) -> Result<Vec<u8>> {
        // Priority order for key sources:
        // 1. VOIRS_ENCRYPTION_KEY environment variable (highest priority)
        // 2. Key from cloud provider's KMS (if configured)
        // 3. Key from config file
        // 4. Derive from access credentials (fallback)

        // Check environment variable first
        if let Ok(key_str) = std::env::var("VOIRS_ENCRYPTION_KEY") {
            if key_str.len() >= 32 {
                tracing::debug!("Using encryption key from VOIRS_ENCRYPTION_KEY environment");
                return Ok(key_str.as_bytes().to_vec());
            } else {
                tracing::warn!(
                    "VOIRS_ENCRYPTION_KEY is too short ({} bytes), deriving with SHA-256",
                    key_str.len()
                );
                let mut hasher = Sha256::new();
                hasher.update(key_str.as_bytes());
                return Ok(hasher.finalize().to_vec());
            }
        }

        // Check config file key
        if let Ok(key_str) = std::env::var("VOIRS_CONFIG_ENCRYPTION_KEY") {
            tracing::debug!("Using encryption key from config file");
            let mut hasher = Sha256::new();
            hasher.update(key_str.as_bytes());
            return Ok(hasher.finalize().to_vec());
        }

        // Fallback: derive key from access credentials
        // This ensures encryption works even without explicit key configuration
        // but credentials must remain consistent for decryption to work
        let key_material = format!(
            "{:?}:{}:{}",
            self.config.provider,
            self.config.bucket_name,
            self.config
                .access_key
                .as_ref()
                .unwrap_or(&"voirs-default".to_string())
        );

        tracing::warn!(
            "No explicit encryption key configured, deriving from credentials (secure but requires consistent config)"
        );

        let mut hasher = Sha256::new();
        hasher.update(key_material.as_bytes());
        // Add salt for additional security
        hasher.update(b"voirs-cloud-storage-encryption-v1");

        Ok(hasher.finalize().to_vec())
    }

    // Cloud provider client creation methods
    async fn create_aws_client(&self) -> Result<()> {
        // This would create an AWS SDK client in a real implementation
        // For now, we'll simulate successful client creation
        tracing::debug!("Created AWS S3 client");
        Ok(())
    }

    async fn create_azure_client(&self) -> Result<()> {
        // This would create an Azure SDK client in a real implementation
        tracing::debug!("Created Azure Blob Storage client");
        Ok(())
    }

    async fn create_gcp_client(&self) -> Result<()> {
        // This would create a Google Cloud SDK client in a real implementation
        tracing::debug!("Created Google Cloud Storage client");
        Ok(())
    }

    async fn create_s3_compatible_client(&self) -> Result<()> {
        // This would create an S3-compatible client in a real implementation
        tracing::debug!("Created S3-compatible client");
        Ok(())
    }

    // AWS-specific helper methods
    async fn aws_multipart_upload(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        tracing::debug!("AWS multipart upload for {}", remote_path);
        // Simulate multipart upload processing
        tokio::time::sleep(tokio::time::Duration::from_millis(100)).await;
        Ok(())
    }

    async fn aws_single_upload(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        tracing::debug!("AWS single upload for {}", remote_path);
        // Simulate single upload processing
        tokio::time::sleep(tokio::time::Duration::from_millis(50)).await;
        Ok(())
    }

    async fn aws_get_object(&self, remote_path: &str) -> Result<Vec<u8>> {
        tracing::debug!("AWS get object for {}", remote_path);
        // Simulate object download with realistic content
        Ok(format!("AWS content for {}", remote_path).into_bytes())
    }

    // Azure-specific helper methods
    async fn azure_put_blob(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        tracing::debug!("Azure put blob for {}", remote_path);
        tokio::time::sleep(tokio::time::Duration::from_millis(50)).await;
        Ok(())
    }

    async fn azure_get_blob(&self, remote_path: &str) -> Result<Vec<u8>> {
        tracing::debug!("Azure get blob for {}", remote_path);
        Ok(format!("Azure content for {}", remote_path).into_bytes())
    }

    // GCP-specific helper methods
    async fn gcp_upload_object(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        tracing::debug!("GCP upload object for {}", remote_path);
        tokio::time::sleep(tokio::time::Duration::from_millis(50)).await;
        Ok(())
    }

    async fn gcp_download_object(&self, remote_path: &str) -> Result<Vec<u8>> {
        tracing::debug!("GCP download object for {}", remote_path);
        Ok(format!("GCP content for {}", remote_path).into_bytes())
    }

    // S3-compatible helper methods
    async fn s3_compatible_put_object(&self, remote_path: &str, content: &[u8]) -> Result<()> {
        tracing::debug!("S3-compatible put object for {}", remote_path);
        tokio::time::sleep(tokio::time::Duration::from_millis(50)).await;
        Ok(())
    }

    async fn s3_compatible_get_object(&self, remote_path: &str) -> Result<Vec<u8>> {
        tracing::debug!("S3-compatible get object for {}", remote_path);
        Ok(format!("S3-compatible content for {}", remote_path).into_bytes())
    }
}

/// Calculate SHA256 checksum of data
fn calculate_file_checksum(data: &[u8]) -> String {
    let mut hasher = Sha256::new();
    hasher.update(data);
    let result = hasher.finalize();
    format!("{:x}", result)
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct SyncResult {
    pub uploaded_files: u32,
    pub downloaded_files: u32,
    pub skipped_files: u32,
    pub failed_uploads: u32,
    pub failed_downloads: u32,
    pub errors: Vec<String>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct StorageStats {
    pub total_files: usize,
    pub local_files: usize,
    pub total_size_bytes: u64,
    pub last_sync_timestamp: u64,
    pub cache_directory: PathBuf,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CleanupResult {
    pub removed_files: u32,
    pub freed_bytes: u64,
    pub errors: Vec<String>,
}

impl SyncManifest {
    fn new() -> Self {
        Self {
            version: 1,
            last_sync_timestamp: 0,
            items: Vec::new(),
            total_size_bytes: 0,
            checksum: String::new(),
        }
    }
}

impl SyncResult {
    fn new() -> Self {
        Self {
            uploaded_files: 0,
            downloaded_files: 0,
            skipped_files: 0,
            failed_uploads: 0,
            failed_downloads: 0,
            errors: Vec::new(),
        }
    }
}

impl Default for CloudStorageConfig {
    fn default() -> Self {
        Self {
            provider: StorageProvider::S3Compatible,
            bucket_name: "voirs-models".to_string(),
            region: "us-west-1".to_string(),
            access_key: None,
            secret_key: None,
            endpoint: None,
            encryption_enabled: true,
            compression_enabled: true,
            sync_interval_seconds: 3600, // 1 hour
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use tempfile::TempDir;

    #[tokio::test]
    async fn test_storage_manager_creation() {
        let temp_dir = TempDir::new().unwrap();
        let config = CloudStorageConfig::default();

        let manager = CloudStorageManager::new(config, temp_dir.path().to_path_buf());
        assert!(manager.is_ok());
    }

    #[tokio::test]
    async fn test_add_to_sync() {
        let temp_dir = TempDir::new().unwrap();
        let config = CloudStorageConfig::default();
        let mut manager = CloudStorageManager::new(config, temp_dir.path().to_path_buf()).unwrap();

        // Create a test file
        let test_file = temp_dir.path().join("test.txt");
        fs::write(&test_file, "test content").await.unwrap();

        let result = manager
            .add_to_sync(
                test_file,
                "remote/test.txt".to_string(),
                SyncDirection::Upload,
            )
            .await;

        assert!(result.is_ok());
        assert_eq!(manager.sync_manifest.items.len(), 1);
    }

    #[tokio::test]
    async fn test_storage_stats() {
        let temp_dir = TempDir::new().unwrap();
        let config = CloudStorageConfig::default();
        let manager = CloudStorageManager::new(config, temp_dir.path().to_path_buf()).unwrap();

        let stats = manager.get_storage_stats().await;
        assert!(stats.is_ok());

        let stats = stats.unwrap();
        assert_eq!(stats.total_files, 0);
        assert_eq!(stats.local_files, 0);
    }

    #[test]
    fn test_sync_direction_serialization() {
        let direction = SyncDirection::Bidirectional;
        let serialized = serde_json::to_string(&direction);
        assert!(serialized.is_ok());

        let deserialized: Result<SyncDirection, _> = serde_json::from_str(&serialized.unwrap());
        assert!(deserialized.is_ok());
    }
}