gen-bsky 0.1.22

#[cfg_attr(doc, aquamarine::aquamarine)]
/// # Post Module Documentation
///
/// ## Overview
///
/// The `post` module provides functionality for managing and publishing blog posts to Bluesky.
/// It handles the complete workflow from loading post files to authenticating with Bluesky,
/// publishing posts, and managing post lifecycle including cleanup of successfully posted content.
///
/// ## Module Architecture
///
/// ```mermaid
/// graph TD
///     A["Post Files (.post)"] --> B["Post::load()"]
///     B --> C["BskyPost Collection"]
///     C --> D["Post::post_to_bluesky()"]
///     D --> E["Bluesky Authentication"]
///     E --> F["Publish Posts"]
///     F --> G["Update Post States"]
///     G --> H["Post::delete_posted_posts()"]
///     H --> I["Cleanup Files"]
/// ```
///
/// ## Post Lifecycle
///
/// Posts progress through several states during their lifecycle:
///
/// 1. **Read**: Posts are loaded from `.post` files and ready for publishing
/// 2. **Posted**: Posts have been successfully published to Bluesky
/// 3. **Deleted**: Post files have been cleaned up after successful publishing
///
/// ```mermaid
/// stateDiagram-v2
///     [*] --> Read: Load from file
///     Read --> Posted: Successful publish
///     Read --> Read: Publish error
///     Posted --> Deleted: File cleanup
///     Deleted --> [*]
/// ```
///
/// ## Key Components
///
/// - **Post**: Main struct managing the posting workflow and Bluesky credentials
/// - **BskyPost**: Individual post representation with state tracking
/// - **BskyPostState**: Enum representing the current state of each post
/// - **PostError**: Comprehensive error handling for all posting operations
///
/// ## Authentication
///
/// The module handles Bluesky authentication using:
/// - User identifier (handle or email)
/// - Password or app-specific password
/// - Automatic session management and labeler configuration
///
/// ## File Format
///
/// Posts are expected to be stored as JSON files with `.post` extension containing
/// Bluesky `RecordData` structures that can be directly published to the platform.
///
/// ## Testing Mode
///
/// The module supports a testing mode activated by the `TESTING` environment variable,
/// which simulates posting without actually publishing to Bluesky.
///
/// ## Error Handling
///
/// Comprehensive error handling covers:
/// - Authentication failures
/// - File I/O errors
/// - JSON deserialization errors
/// - Bluesky API errors
/// - Network connectivity issues
///
/// ## Usage Example
///
/// ```rust,ignore
/// use crate::post::Post;
///
/// async fn publish_posts() -> Result<(), Box<dyn std::error::Error>> {
///     let mut poster = Post::new("user@example.com", "password")?;
///     
///     poster
///         .load("./posts")?        // Load .post files
///         .post_to_bluesky().await? // Publish to Bluesky
///         .delete_posted_posts()?;  // Clean up successful posts
///         
///     println!("Cleaned up {} posts", poster.count_deleted());
///     Ok(())
/// }
/// ```
use std::{fmt::Display, fs, io::BufReader, path::Path};

const TESTING_FLAG: &str = "TESTING";
pub(crate) mod bsky_post;

use bsky_post::{BskyPost, BskyPostState};
use bsky_sdk::{agent::config::Config as BskyConfig, BskyAgent};
// use serde::{Deserialize, Serialize};
use thiserror::Error;

/// # PostError - Comprehensive Error Handling for Post Operations
///
/// The `PostError` enum provides detailed error information for all operations
/// in the post module, from authentication to file handling to API communication.
///
/// ## Error Categories
///
/// ### Authentication Errors
/// - `NoBlueskyIdentifier`: Missing or empty user identifier
/// - `NoBlueskyPassword`: Missing or empty password
/// - `BlueskyLoginError`: Authentication failure with Bluesky
///
/// ### File System Errors
/// - `Io`: File operations, directory reading, or file deletion errors
///
/// ### Data Processing Errors
/// - `SerdeJsonError`: JSON parsing errors when reading post files
///
/// ### API Communication Errors
/// - `BskySdk`: Bluesky SDK errors including network and API issues
///
/// ## Error Handling Strategy
///
/// ```rust,ignore
/// use crate::post::{Post, PostError};
///
/// async fn handle_posting() {
///     match Post::new("user", "pass") {
///         Ok(mut poster) => {
///             if let Err(e) = poster.load("./posts") {
///                 match e {
///                     PostError::Io(io_err) => eprintln!("File error: {}", io_err),
///                     PostError::SerdeJsonError(json_err) => eprintln!("JSON error: {}", json_err),
///                     _ => eprintln!("Other error: {}", e),
///                 }
///             }
///         },
///         Err(PostError::NoBlueskyIdentifier) => eprintln!("Missing username"),
///         Err(PostError::NoBlueskyPassword) => eprintln!("Missing password"),
///         Err(e) => eprintln!("Setup error: {}", e),
///     }
/// }
/// ```
///
/// ## Recovery Strategies
///
/// - **Authentication errors**: Verify credentials and network connectivity
/// - **File errors**: Check file permissions and directory structure
/// - **JSON errors**: Validate post file format and content
/// - **API errors**: Check network connectivity and Bluesky service status
#[non_exhaustive]
#[derive(Debug, Error)]
pub enum PostError {
    /// Bluesky identifier required to post to bluesky not provided.
    ///
    /// This error occurs when:
    /// - An empty string is passed as the identifier to `Post::new()`
    /// - The identifier parameter is whitespace-only
    ///
    /// ## Resolution
    /// Provide a valid Bluesky handle (e.g., "user.bsky.social") or email address.
    #[error("No bluesky identifier provided")]
    NoBlueskyIdentifier,

    /// Bluesky password required to post to bluesky not provided.
    ///
    /// This error occurs when:
    /// - An empty string is passed as the password to `Post::new()`
    /// - The password parameter is whitespace-only
    ///
    /// ## Resolution
    /// Provide a valid password or app-specific password for the Bluesky account.
    #[error("No bluesky password provided")]
    NoBlueskyPassword,

    /// Bluesky SDK reports a login error.
    ///
    /// This error occurs when:
    /// - Invalid credentials are provided
    /// - Network connectivity issues prevent authentication
    /// - Bluesky service is temporarily unavailable
    /// - Account is suspended or restricted
    ///
    /// ## Resolution
    /// - Verify username and password are correct
    /// - Check network connectivity
    /// - Verify account status on Bluesky
    /// - Wait and retry if service issues are suspected
    #[error("bsky_sdk create_session error says: {0:?}")]
    BlueskyLoginError(String),

    /// Error reported from the std::io module.
    ///
    /// This error occurs during:
    /// - Reading post directories in `load()`
    /// - Opening post files for reading
    /// - Deleting posted files in `delete_posted_posts()`
    /// - Any other file system operations
    ///
    /// ## Common Causes
    /// - File or directory doesn't exist
    /// - Insufficient permissions
    /// - Disk full or I/O errors
    /// - File in use by another process
    #[error("io error says: {0:?}")]
    Io(#[from] std::io::Error),

    /// Error reported from the serde_json crate.
    ///
    /// This error occurs when:
    /// - Post files contain invalid JSON
    /// - JSON structure doesn't match expected RecordData format
    /// - File encoding issues
    ///
    /// ## Resolution
    /// - Validate JSON syntax in post files
    /// - Ensure post files match Bluesky RecordData schema
    /// - Check file encoding (should be UTF-8)
    #[error("serde_json create_session error says: {0:?}")]
    SerdeJsonError(#[from] serde_json::error::Error),

    /// Error reported from the bsky_sdk crate.
    ///
    /// This error occurs during:
    /// - API calls to Bluesky
    /// - Network communication
    /// - Post creation and submission
    /// - Preference retrieval
    ///
    /// ## Common Causes
    /// - Network connectivity issues
    /// - API rate limiting
    /// - Invalid post content
    /// - Service temporarily unavailable
    #[error("bsky_sdk error says: {0:?}")]
    BskySdk(#[from] bsky_sdk::Error),

    /// Error writing back to frontmatter.
    #[error("frontmatter write-back error: {0:?}")]
    FmWrite(#[from] crate::frontmatter_writeback::FmWriteError),
}

/// # Post - Bluesky Post Management and Publishing
///
/// The `Post` struct manages the complete lifecycle of publishing posts to Bluesky,
/// from loading post files to authentication, publishing, and cleanup.
///
/// ## Fields
///
/// - `bsky_posts`: Collection of individual posts with state tracking
/// - `id`: Bluesky user identifier (handle or email)
/// - `pwd`: Authentication password or app-specific password
///
/// ## Memory Characteristics
///
/// - Memory usage scales linearly with the number of posts loaded
/// - Credentials are stored as owned `String` instances for the session duration
/// - Post data is kept in memory during the entire publishing workflow
/// - Implements `Clone` for flexibility, but credentials are duplicated
///
/// ## Usage Pattern
///
/// ```rust,ignore
/// use crate::post::Post;
///
/// async fn publish_workflow() -> Result<(), Box<dyn std::error::Error>> {
///     let mut poster = Post::new("user.bsky.social", "app-password")?;
///     
///     // Chain operations for fluent API usage
///     poster
///         .load("./post_directory")?        // Load all .post files
///         .post_to_bluesky().await?         // Authenticate and publish
///         .delete_posted_posts()?;          // Clean up successful posts
///         
///     println!("Published and cleaned up {} posts", poster.count_deleted());
///     Ok(())
/// }
/// ```
///
/// ## Thread Safety
///
/// This struct is not thread-safe due to:
/// - Mutable references returned by methods
/// - Internal state mutations during posting
/// - File system operations
///
/// ## Credential Security
///
/// - Credentials are stored in memory as plain text
/// - No automatic credential clearing (consider `zeroize` for sensitive use)
/// - Credentials are logged only in debug builds with appropriate redaction
#[derive(Default, Debug, Clone)]
pub struct Post {
    /// Collection of Bluesky posts with individual state tracking
    bsky_posts: Vec<BskyPost>,

    /// Bluesky user identifier (handle like "user.bsky.social" or email)
    id: String,

    /// Authentication password or app-specific password
    pwd: String,
    // Future: Track sent posts for additional state management
    // sent_posts: Vec<PathBuf>,
}

impl Post {
    /// Creates a new Post instance with Bluesky credentials.
    ///
    /// Initializes a Post struct with the provided Bluesky authentication credentials.
    /// The post collection starts empty and credentials are validated for basic requirements.
    ///
    /// ## Parameters
    ///
    /// - `id`: Bluesky user identifier (handle like "user.bsky.social" or email address)
    /// - `password`: Account password or app-specific password
    ///
    /// ## Returns
    ///
    /// - `Ok(Post)`: Successfully created Post instance ready for loading posts
    /// - `Err(PostError)`: Validation failure for credentials
    ///
    /// ## Errors
    ///
    /// - `PostError::NoBlueskyIdentifier`: Empty or whitespace-only identifier
    /// - `PostError::NoBlueskyPassword`: Empty or whitespace-only password
    ///
    /// ## Security Considerations
    ///
    /// - Credentials are stored as plain text in memory
    /// - No validation of credential format or existence
    /// - Consider using app-specific passwords instead of main account passwords
    ///
    /// ## Examples
    ///
    /// ```rust,ignore
    /// use crate::post::Post;
    ///
    /// // Using handle format
    /// let poster = Post::new("user.bsky.social", "app-password")?;
    ///
    /// // Using email format  
    /// let poster = Post::new("user@example.com", "password")?;
    ///
    /// // Error handling
    /// match Post::new("", "password") {
    ///     Err(PostError::NoBlueskyIdentifier) => println!("Missing username"),
    ///     Ok(_) => println!("Success"),
    ///     Err(e) => println!("Other error: {}", e),
    /// }
    /// ```
    pub fn new(id: &str, password: &str) -> Result<Self, PostError> {
        if id.is_empty() {
            return Err(PostError::NoBlueskyIdentifier);
        };

        if password.is_empty() {
            return Err(PostError::NoBlueskyPassword);
        };

        Ok(Post {
            id: id.to_string(),
            pwd: password.to_string(),
            ..Default::default()
        })
    }

    /// Loads Bluesky post documents from a specified directory.
    ///
    /// Scans the provided directory for files with `.post` extension and loads them
    /// as JSON-formatted Bluesky `RecordData`. Successfully loaded posts are added
    /// to the internal collection with `Read` state.
    ///
    /// ## Parameters
    ///
    /// - `directory`: Path to directory containing `.post` files (implements `AsRef<Path> + Display`)
    ///
    /// ## Returns
    ///
    /// - `Ok(&mut Self)`: Fluent interface for method chaining
    /// - `Err(PostError)`: File system or parsing errors
    ///
    /// ## Errors
    ///
    /// - `PostError::Io`: Directory doesn't exist, permission denied, or I/O errors
    /// - `PostError::SerdeJsonError`: Invalid JSON format or schema mismatch
    ///
    /// ## behaviour
    ///
    /// - Only processes files with `.post` extension
    /// - Ignores files that don't match the extension
    /// - Accumulated posts from multiple `load()` calls
    /// - Non-UTF-8 filenames may cause panics (uses `.unwrap()`)
    ///
    /// ## File Format
    ///
    /// Post files must contain valid JSON matching Bluesky's `RecordData` schema:
    /// ```json
    /// {
    ///   "text": "Your post content here",
    ///   "createdAt": "2024-01-01T00:00:00.000Z",
    ///   "langs": ["en"]
    /// }
    /// ```
    ///
    /// ## Performance
    ///
    /// - **Time Complexity**: O(n) where n is the number of `.post` files
    /// - **Memory**: Loads all posts into memory simultaneously
    /// - **I/O**: Sequential file reading, not optimized for large directories
    ///
    /// ## Examples
    ///
    /// ```rust,ignore
    /// use crate::post::Post;
    ///
    /// let mut poster = Post::new("user", "pass")?;
    ///
    /// // Load from single directory
    /// poster.load("./posts")?;
    ///
    /// // Load from multiple directories (accumulative)
    /// poster.load("./posts1")?
    ///       .load("./posts2")?;
    ///
    /// // Using PathBuf
    /// use std::path::PathBuf;
    /// let post_dir = PathBuf::from("./posts");
    /// poster.load(post_dir)?;
    /// ```
    pub fn load<P>(&mut self, directory: P) -> Result<&mut Self, PostError>
    where
        P: AsRef<Path> + Display,
    {
        let files = fs::read_dir(&directory)?;
        let mut bsky_posts = Vec::new();
        for file in files {
            let file = file?;
            let file_name = file.file_name().into_string().unwrap();
            if file_name.ends_with(".post") {
                let file_path = file.path();
                let post = fs::File::open(&file_path)?;
                let reader = BufReader::new(post);
                let post_file: bsky_post::PostFile = serde_json::from_reader(reader)?;
                let bsky_post = if let Some(src) = post_file.source_path {
                    BskyPost::new_with_source(post_file.record, file_path, src)
                } else {
                    BskyPost::new(post_file.record, file_path)
                };
                bsky_posts.push(bsky_post);
            }
        }
        self.bsky_posts.extend(bsky_posts);
        Ok(self)
    }

    /// Publishes all loaded posts to Bluesky.
    ///
    /// Authenticates with Bluesky using stored credentials, then publishes all posts
    /// currently in `Read` state. Posts are processed sequentially, and individual
    /// failures don't stop the overall process.
    ///
    /// ## Returns
    ///
    /// - `Ok(&mut Self)`: Publishing completed (check individual post states for results)
    /// - `Err(PostError)`: Authentication or SDK initialization failure
    ///
    /// ## Errors
    ///
    /// - `PostError::BlueskyLoginError`: Invalid credentials or authentication failure
    /// - `PostError::BskySdk`: Network errors, API errors, or SDK issues
    ///
    /// ## Async behaviour
    ///
    /// - Establishes Bluesky session asynchronously
    /// - Posts are published sequentially (not concurrently)
    /// - Network timeouts are handled by the underlying SDK
    ///
    /// ## Authentication Flow
    ///
    /// 1. Create BskyAgent with default configuration
    /// 2. Login using stored credentials
    /// 3. Retrieve and configure user preferences
    /// 4. Configure content labelers from preferences
    ///
    /// ## Testing Mode
    ///
    /// When `TESTING` environment variable is set:
    /// - No actual posts are made to Bluesky
    /// - All posts are logged as "successfully posted"
    /// - Post states remain as `Read` (not changed to `Posted`)
    /// - Useful for CI/CD and development testing
    ///
    /// ## Error Recovery
    ///
    /// - Individual post failures are logged and skipped
    /// - Failed posts remain in `Read` state for retry
    /// - Successful posts transition to `Posted` state
    /// - Authentication failure stops the entire process
    ///
    /// ## Logging
    ///
    /// - Info: Authentication success, testing mode, successful posts
    /// - Debug: Post content preview, validation status
    /// - Warn: Individual post failures
    ///
    /// ## Examples
    ///
    /// ```rust,ignore
    /// use crate::post::Post;
    /// use std::env;
    ///
    /// async fn publish_example() -> Result<(), Box<dyn std::error::Error>> {
    ///     let mut poster = Post::new("user", "pass")?;
    ///     poster.load("./posts")?;
    ///
    ///     // Enable testing mode
    ///     env::set_var("TESTING", "1");
    ///     
    ///     // Publish posts
    ///     poster.post_to_bluesky().await?;
    ///
    ///     // Check results
    ///     let posted_count = poster.bsky_posts.iter()
    ///         .filter(|p| p.state() == &BskyPostState::Posted)
    ///         .count();
    ///     println!("Posted {} posts", posted_count);
    ///     
    ///     Ok(())
    /// }
    /// ```
    pub async fn post_to_bluesky(&mut self) -> Result<&mut Self, PostError> {
        let bsky_config = BskyConfig::default();

        let agent = BskyAgent::builder().config(bsky_config).build().await?;

        agent
            .login(&self.id, &self.pwd)
            .await
            .map_err(|e| PostError::BlueskyLoginError(e.to_string()))?;
        // Set labelers from preferences
        let preferences = agent.get_preferences(true).await?;
        agent.configure_labelers_from_preferences(&preferences);
        log::info!("Bluesky login successful!");

        let testing = std::env::var(TESTING_FLAG).is_ok();
        if testing {
            log::info!("No posts will be made to bluesky as this is a test.");
        }

        for bsky_post in &mut self
            .bsky_posts
            .iter_mut()
            .filter(|p| p.state() == &BskyPostState::Read)
        {
            // Skip posts whose source markdown already has [bluesky].published set.
            if let Some(src) = bsky_post.source_path() {
                if crate::frontmatter_writeback::read_bluesky_date_field(src, "published").is_some()
                {
                    log::debug!("Skipping post — [bluesky].published already set in {src:?}");
                    continue;
                }
            }

            log::debug!("Post: {}", bsky_post.post().text.clone());

            if testing {
                // log::debug!("Deleting related file: {:?}", bsky_post.file_path);
                // fs::remove_file(&bsky_post.file_path)?;

                log::info!(
                    "Successfully posted `{}` to Bluesky",
                    bsky_post.file_path().to_string_lossy()
                );
            } else {
                let result = agent.create_record(bsky_post.post().clone()).await;

                let Ok(output) = result else {
                    log::warn!("Error posting to Bluesky: {}", result.err().unwrap());
                    continue;
                };

                log::debug!("Post validation: `{:?}`", output.validation_status.as_ref());

                log::info!(
                    "Successfully posted `{}` to Bluesky",
                    bsky_post
                        .post()
                        .text
                        .split_terminator('\n')
                        .collect::<Vec<&str>>()[0],
                );

                bsky_post.set_state(BskyPostState::Posted);
            };
        }

        Ok(self)
    }

    /// Deletes post files for all successfully posted content.
    ///
    /// Removes the source `.post` files from the filesystem for all posts
    /// currently in `Posted` state, then transitions them to `Deleted` state.
    /// This cleanup step prevents reprocessing of already-published content.
    ///
    /// ## Returns
    ///
    /// - `Ok(&mut Self)`: Cleanup completed (check individual post states for results)
    /// - `Err(PostError)`: File system errors during deletion
    ///
    /// ## Errors
    ///
    /// - `PostError::Io`: File deletion failures, permission issues, or I/O errors
    ///
    /// ## behaviour
    ///
    /// - Only processes posts in `Posted` state
    /// - Individual file deletion failures stop the entire process
    /// - Successfully deleted files transition posts to `Deleted` state
    /// - Files are deleted from filesystem immediately
    ///
    /// ## Safety Considerations
    ///
    /// - **Irreversible operation**: Deleted files cannot be recovered
    /// - Ensure posts are actually published before calling this method
    /// - Consider backup strategies for important content
    /// - File locks or permissions may prevent deletion
    ///
    /// ## Use Cases
    ///
    /// - Cleanup after successful publishing workflow
    /// - Prevent duplicate posting in subsequent runs
    /// - Disk space management
    /// - Automated CI/CD pipeline cleanup
    ///
    /// ## Error Recovery
    ///
    /// - Failed deletions leave posts in `Posted` state
    /// - Partial deletions are possible (some files deleted, others not)
    /// - Manual intervention may be required for locked files
    /// - Consider retry logic for transient filesystem issues
    ///
    /// ## Logging
    ///
    /// - Debug: File paths being deleted
    /// - Info: Successful deletion confirmations with file paths
    ///
    /// ## Examples
    ///
    /// ```rust,ignore
    /// use crate::post::{Post, PostError};
    ///
    /// async fn cleanup_workflow() -> Result<(), PostError> {
    ///     let mut poster = Post::new("user", "pass")?;
    ///     
    ///     poster.load("./posts")?
    ///           .post_to_bluesky().await?
    ///           .delete_posted_posts()?;  // Clean up successful posts
    ///           
    ///     println!("Deleted {} post files", poster.count_deleted());
    ///     Ok(())
    /// }
    ///
    /// // Error handling example
    /// async fn careful_cleanup(mut poster: Post) {
    ///     match poster.delete_posted_posts() {
    ///         Ok(_) => println!("Cleanup successful"),
    ///         Err(PostError::Io(io_err)) => {
    ///             eprintln!("File deletion failed: {}", io_err);
    ///             // Posts remain in Posted state for manual review
    ///         },
    ///         Err(e) => eprintln!("Unexpected error: {}", e),
    ///     }
    /// }
    /// ```
    pub fn delete_posted_posts(&mut self) -> Result<&mut Self, PostError> {
        for bsky_post in &mut self
            .bsky_posts
            .iter_mut()
            .filter(|p| p.state() == &BskyPostState::Posted)
        {
            // Write `published = <today>` back to the source .md file when known.
            if let Some(src) = bsky_post.source_path() {
                let today = crate::draft::today();
                match crate::frontmatter_writeback::write_bluesky_date_field(
                    src,
                    "published",
                    today,
                ) {
                    Ok(()) => log::debug!(
                        "Wrote [bluesky].published = {} to `{}`",
                        today,
                        src.display()
                    ),
                    Err(e) => log::warn!(
                        "Failed to write [bluesky].published to `{}`: {e}",
                        src.display()
                    ),
                }
            }

            log::debug!("Deleting related file: {:?}", bsky_post.file_path());
            fs::remove_file(bsky_post.file_path())?;

            log::info!(
                "Successfully deleted `{}` bluesky post file",
                bsky_post.file_path().to_string_lossy()
            );

            bsky_post.set_state(BskyPostState::Deleted);
        }

        Ok(self)
    }

    /// Returns the count of posts that have been successfully deleted.
    ///
    /// Counts all posts currently in `Deleted` state, which indicates they were
    /// successfully published to Bluesky and their source files have been removed
    /// from the filesystem.
    ///
    /// ## Returns
    ///
    /// - `usize`: Number of posts in `Deleted` state
    ///
    /// ## Performance
    ///
    /// - **Time Complexity**: O(n) where n is the total number of loaded posts
    /// - **Space Complexity**: O(1) constant space usage
    /// - **Cost**: Iterates through all posts to count matching states
    ///
    /// ## Use Cases
    ///
    /// - Reporting and logging after cleanup operations
    /// - Verification that cleanup completed successfully
    /// - Metrics collection for automated workflows
    /// - Progress tracking in batch processing scenarios
    ///
    /// ## State Transitions
    ///
    /// Posts reach `Deleted` state through this workflow:
    /// 1. `Read` (after loading from files)
    /// 2. `Posted` (after successful publish to Bluesky)
    /// 3. `Deleted` (after successful file cleanup)
    ///
    /// ## Examples
    ///
    /// ```rust,ignore
    /// use crate::post::Post;
    ///
    /// async fn workflow_with_reporting() -> Result<(), Box<dyn std::error::Error>> {
    ///     let mut poster = Post::new("user", "pass")?;
    ///     
    ///     poster.load("./posts")?;
    ///     let initial_count = poster.bsky_posts.len();
    ///     println!("Loaded {} posts", initial_count);
    ///     
    ///     poster.post_to_bluesky().await?
    ///           .delete_posted_posts()?;
    ///           
    ///     let deleted_count = poster.count_deleted();
    ///     println!("Successfully processed {} of {} posts", deleted_count, initial_count);
    ///     
    ///     if deleted_count < initial_count {
    ///         println!("Warning: {} posts may have failed", initial_count - deleted_count);
    ///     }
    ///     
    ///     Ok(())
    /// }
    /// ```
    pub fn count_deleted(&self) -> usize {
        self.bsky_posts
            .iter()
            .filter(|b| b.state() == &BskyPostState::Deleted)
            .count()
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use std::env;
    use std::fs;
    use std::io::Write;
    use tempfile::TempDir;

    /// Helper function to create a test Post instance
    fn create_test_post() -> Result<Post, PostError> {
        Post::new("test.user.bsky.social", "test-password")
    }

    /// Helper function to create a temporary directory with test post files
    fn create_test_posts_directory() -> Result<TempDir, std::io::Error> {
        let temp_dir = tempfile::tempdir()?;

        // Create valid post file
        let post_content = r#"{
            "text": "Test post content",
            "createdAt": "2024-01-01T00:00:00.000Z",
            "langs": ["en"]
        }"#;
        let post_path = temp_dir.path().join("test1.post");
        let mut post_file = fs::File::create(post_path)?;
        post_file.write_all(post_content.as_bytes())?;

        // Create another valid post file
        let post_content2 = r#"{
            "text": "Another test post",
            "createdAt": "2024-01-02T00:00:00.000Z",
            "langs": ["en", "es"]
        }"#;
        let post_path2 = temp_dir.path().join("test2.post");
        let mut post_file2 = fs::File::create(post_path2)?;
        post_file2.write_all(post_content2.as_bytes())?;

        // Create a non-post file (should be ignored)
        let other_file = temp_dir.path().join("readme.txt");
        let mut other = fs::File::create(other_file)?;
        other.write_all(b"This is not a post file")?;

        Ok(temp_dir)
    }

    /// Helper function to create invalid JSON post file
    fn create_invalid_post_file(temp_dir: &TempDir) -> Result<(), std::io::Error> {
        let invalid_content = r#"{
            "text": "Invalid JSON",
            "createdAt": "2024-01-01T00:00:00.000Z"
            // Missing closing brace and comma
        "#;
        let invalid_path = temp_dir.path().join("invalid.post");
        let mut invalid_file = fs::File::create(invalid_path)?;
        invalid_file.write_all(invalid_content.as_bytes())?;
        Ok(())
    }

    // Constructor tests
    #[test]
    fn test_post_new_success() {
        let result = Post::new("test.user", "password123");
        assert!(result.is_ok());

        let post = result.unwrap();
        assert_eq!(post.id, "test.user");
        assert_eq!(post.pwd, "password123");
        assert_eq!(post.bsky_posts.len(), 0);
    }

    #[test]
    fn test_post_new_empty_identifier() {
        let result = Post::new("", "password");
        assert!(matches!(result, Err(PostError::NoBlueskyIdentifier)));
    }

    #[test]
    fn test_post_new_empty_password() {
        let result = Post::new("user", "");
        assert!(matches!(result, Err(PostError::NoBlueskyPassword)));
    }

    #[test]
    fn test_post_new_both_empty() {
        let result = Post::new("", "");
        // Should fail on identifier first
        assert!(matches!(result, Err(PostError::NoBlueskyIdentifier)));
    }

    #[test]
    fn test_post_new_whitespace_identifier() {
        let result = Post::new("   ", "password");
        // Current implementation allows whitespace, but should be empty string
        assert!(result.is_ok());
    }

    // Load method tests
    #[test]
    fn test_load_success() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;

        let result = post.load(temp_dir.path().to_string_lossy().to_string());
        assert!(result.is_ok());

        assert_eq!(post.bsky_posts.len(), 2);

        // Check that all posts are in Read state
        for bsky_post in &post.bsky_posts {
            assert_eq!(bsky_post.state(), &BskyPostState::Read);
        }

        // Verify post content - posts can be loaded in any order
        let post_texts: Vec<&str> = post
            .bsky_posts
            .iter()
            .map(|p| p.post().text.as_str())
            .collect();
        assert!(post_texts.contains(&"Test post content"));
        assert!(post_texts.contains(&"Another test post"));

        Ok(())
    }

    #[test]
    fn test_load_nonexistent_directory() {
        let mut post = create_test_post().unwrap();
        let result = post.load("/nonexistent/directory");
        assert!(matches!(result, Err(PostError::Io(_))));
    }

    #[test]
    fn test_load_invalid_json() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;
        create_invalid_post_file(&temp_dir)?;

        let result = post.load(temp_dir.path().to_string_lossy().to_string());
        // Should fail due to invalid JSON
        assert!(matches!(result, Err(PostError::SerdeJsonError(_))));

        Ok(())
    }

    #[test]
    fn test_load_empty_directory() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = tempfile::tempdir()?;

        let result = post.load(temp_dir.path().to_string_lossy().to_string());
        assert!(result.is_ok());
        assert_eq!(post.bsky_posts.len(), 0);

        Ok(())
    }

    #[test]
    fn test_load_no_post_files() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = tempfile::tempdir()?;

        // Create non-post files
        let txt_file = temp_dir.path().join("readme.txt");
        fs::write(txt_file, "Not a post file")?;

        let json_file = temp_dir.path().join("config.json");
        fs::write(json_file, "{\"config\": \"value\"}")?;

        let result = post.load(temp_dir.path().to_string_lossy().to_string());
        assert!(result.is_ok());
        assert_eq!(post.bsky_posts.len(), 0);

        Ok(())
    }

    #[test]
    fn test_load_accumulative() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;

        // Create first directory with posts
        let temp_dir1 = create_test_posts_directory()?;
        post.load(temp_dir1.path().to_string_lossy().to_string())?;
        assert_eq!(post.bsky_posts.len(), 2);

        // Create second directory with more posts
        let temp_dir2 = tempfile::tempdir()?;
        let post_content = r#"{
            "text": "Third post",
            "createdAt": "2024-01-03T00:00:00.000Z",
            "langs": ["fr"]
        }"#;
        let post_path = temp_dir2.path().join("test3.post");
        fs::write(post_path, post_content)?;

        post.load(temp_dir2.path().to_string_lossy().to_string())?;
        assert_eq!(post.bsky_posts.len(), 3);

        Ok(())
    }

    // Post to Bluesky tests (using testing mode)
    #[tokio::test]
    async fn test_post_to_bluesky_testing_mode() -> Result<(), Box<dyn std::error::Error>> {
        unsafe { env::set_var("TESTING", "1") };

        let mut post = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;
        post.load(temp_dir.path().to_string_lossy().to_string())?;

        // In testing mode, this should not fail even with fake credentials
        let result = post.post_to_bluesky().await;

        // Clean up environment variable
        unsafe { env::remove_var("TESTING") };

        // Note: This test might fail due to actual network calls even in testing mode
        // depending on the implementation. The current code still tries to authenticate.
        // For a proper test, we'd need to mock the BskyAgent.

        // If authentication fails, that's expected with fake credentials
        match result {
            Err(PostError::BlueskyLoginError(_)) => {
                // Expected with fake credentials
            }
            Ok(_) => {
                // Success in testing mode (if implementation is properly mocked)
            }
            Err(e) => {
                // Other errors might indicate implementation issues
                println!("Unexpected error: {e:?}");
            }
        }

        Ok(())
    }

    // Delete posted posts tests
    #[test]
    fn test_delete_posted_posts_no_posted() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;
        post.load(temp_dir.path().to_string_lossy().to_string())?;

        // No posts are in Posted state yet
        let result = post.delete_posted_posts();
        assert!(result.is_ok());

        // Verify files still exist
        assert!(temp_dir.path().join("test1.post").exists());
        assert!(temp_dir.path().join("test2.post").exists());

        Ok(())
    }

    #[test]
    fn test_delete_posted_posts_with_posted() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;
        post.load(temp_dir.path().to_string_lossy().to_string())?;

        // Manually set one post to Posted state
        let first_post_file_path = post.bsky_posts[0].file_path().clone();
        post.bsky_posts[0].set_state(BskyPostState::Posted);

        let result = post.delete_posted_posts();
        assert!(result.is_ok());

        // Verify the posted file was deleted
        assert!(!first_post_file_path.exists());

        // Count files to verify only one was deleted
        let remaining_files: Vec<_> = ["test1.post", "test2.post"]
            .iter()
            .filter(|filename| temp_dir.path().join(filename).exists())
            .collect();
        assert_eq!(remaining_files.len(), 1);

        // Verify state transition
        assert_eq!(post.bsky_posts[0].state(), &BskyPostState::Deleted);
        assert_eq!(post.bsky_posts[1].state(), &BskyPostState::Read);

        Ok(())
    }

    #[test]
    fn test_delete_posted_posts_file_not_found() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;
        post.load(temp_dir.path().to_string_lossy().to_string())?;

        // Find the post that corresponds to test1.post and delete its file
        let test1_post_index = post
            .bsky_posts
            .iter()
            .position(|p| p.file_path().file_name().unwrap().to_str().unwrap() == "test1.post")
            .expect("Should find test1.post");

        // Remove the actual file
        fs::remove_file(post.bsky_posts[test1_post_index].file_path())?;

        // Set the post to Posted state
        post.bsky_posts[test1_post_index].set_state(BskyPostState::Posted);

        let result = post.delete_posted_posts();
        // Should fail because file doesn't exist
        assert!(matches!(result, Err(PostError::Io(_))));

        Ok(())
    }

    // Count deleted tests
    #[test]
    fn test_count_deleted_none() {
        let post = create_test_post().unwrap();
        assert_eq!(post.count_deleted(), 0);
    }

    #[test]
    fn test_count_deleted_with_deleted_posts() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;
        post.load(temp_dir.path().to_string_lossy().to_string())?;

        // Set posts to different states
        post.bsky_posts[0].set_state(BskyPostState::Deleted);
        post.bsky_posts[1].set_state(BskyPostState::Posted);

        assert_eq!(post.count_deleted(), 1);

        Ok(())
    }

    // Error handling tests
    #[test]
    fn test_error_display() {
        let errors = vec![
            PostError::NoBlueskyIdentifier,
            PostError::NoBlueskyPassword,
            PostError::BlueskyLoginError("Login failed".to_string()),
            PostError::Io(std::io::Error::new(
                std::io::ErrorKind::NotFound,
                "File not found",
            )),
        ];

        for error in errors {
            let error_string = format!("{error}");
            assert!(!error_string.is_empty());
        }
    }

    // Clone and Debug tests
    #[test]
    fn test_post_clone() -> Result<(), Box<dyn std::error::Error>> {
        let mut original = create_test_post()?;
        let temp_dir = create_test_posts_directory()?;
        original.load(temp_dir.path().to_string_lossy().to_string())?;

        let cloned = original.clone();
        assert_eq!(original.id, cloned.id);
        assert_eq!(original.pwd, cloned.pwd);
        assert_eq!(original.bsky_posts.len(), cloned.bsky_posts.len());

        Ok(())
    }

    #[test]
    fn test_post_debug() {
        let post = create_test_post().unwrap();
        let debug_str = format!("{post:?}");
        assert!(debug_str.contains("Post"));
    }

    // Default implementation test
    #[test]
    fn test_post_default() {
        let post = Post::default();
        assert!(post.id.is_empty());
        assert!(post.pwd.is_empty());
        assert_eq!(post.bsky_posts.len(), 0);
    }

    // Fluent interface tests
    #[test]
    fn test_fluent_interface() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir1 = create_test_posts_directory()?;
        let temp_dir2 = tempfile::tempdir()?;

        // Create a post in second directory
        let post_content = r#"{
            "text": "Fluent test",
            "createdAt": "2024-01-04T00:00:00.000Z"
        }"#;
        fs::write(temp_dir2.path().join("fluent.post"), post_content)?;

        // Test method chaining
        let result = post
            .load(temp_dir1.path().to_string_lossy().to_string())?
            .load(temp_dir2.path().to_string_lossy().to_string());

        assert!(result.is_ok());
        assert_eq!(post.bsky_posts.len(), 3);

        Ok(())
    }

    // RED: source_path loading and published write-back (issue #909)

    fn create_post_file_with_source_path(
        dir: &std::path::Path,
        filename: &str,
        source_path: &str,
    ) -> std::path::PathBuf {
        let content = format!(
            r#"{{"text":"Test","createdAt":"2026-04-03T00:00:00.000000Z","langs":null,"reply":null,"embed":null,"facets":null,"tags":null,"entities":null,"labels":null,"source_path":"{source_path}"}}"#
        );
        let path = dir.join(filename);
        fs::write(&path, content).unwrap();
        path
    }

    fn create_md_with_bluesky_created(dir: &std::path::Path, filename: &str) -> std::path::PathBuf {
        let content = "+++\ntitle = \"Test\"\ndescription = \"test\"\ndate = 2026-04-03\n\n[bluesky]\ndescription = \"bsky desc\"\ncreated = 2026-04-03\n+++\n\nBody.";
        let path = dir.join(filename);
        fs::write(&path, content).unwrap();
        path
    }

    #[test]
    fn test_load_reads_source_path_from_post_file() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = tempfile::tempdir()?;
        let md_path = temp_dir.path().join("my-post.md");
        create_post_file_with_source_path(temp_dir.path(), "abc.post", &md_path.to_string_lossy());

        post.load(temp_dir.path().to_string_lossy().to_string())?;
        assert_eq!(post.bsky_posts.len(), 1);
        assert_eq!(
            post.bsky_posts[0].source_path(),
            Some(&md_path),
            "source_path should be loaded from .post file"
        );
        Ok(())
    }

    #[test]
    fn test_delete_posted_posts_writes_published_to_frontmatter() {
        // delete_posted_posts is where the write-back happens; no network needed.
        let mut post = create_test_post().unwrap();
        let temp_dir = tempfile::tempdir().unwrap();

        // Create a .md file with [bluesky].created
        let md_path = create_md_with_bluesky_created(temp_dir.path(), "my-post.md");

        // Create a .post file that references this .md
        create_post_file_with_source_path(temp_dir.path(), "abc.post", &md_path.to_string_lossy());

        post.load(temp_dir.path().to_string_lossy().to_string())
            .unwrap();
        assert_eq!(post.bsky_posts.len(), 1);

        // Simulate a successful post by setting state to Posted
        post.bsky_posts[0].set_state(BskyPostState::Posted);

        post.delete_posted_posts().unwrap();

        let md_content = fs::read_to_string(&md_path).unwrap();
        assert!(
            md_content.contains("published ="),
            ".md file should have published date after delete_posted_posts: {md_content}"
        );
    }

    // Memory and performance tests
    #[test]
    fn test_large_number_of_posts() -> Result<(), Box<dyn std::error::Error>> {
        let mut post = create_test_post()?;
        let temp_dir = tempfile::tempdir()?;

        // Create 100 post files
        for i in 0..100 {
            let post_content = format!(
                r#"{{
                    "text": "Post number {i}",
                    "createdAt": "2024-01-01T00:00:00.000Z"
                }}"#
            );
            let post_path = temp_dir.path().join(format!("post{i}.post"));
            fs::write(post_path, post_content)?;
        }

        let result = post.load(temp_dir.path().to_string_lossy().to_string());
        assert!(result.is_ok());
        assert_eq!(post.bsky_posts.len(), 100);

        // Test counting with different states
        for i in 0..30 {
            post.bsky_posts[i].set_state(BskyPostState::Posted);
        }
        for i in 30..50 {
            post.bsky_posts[i].set_state(BskyPostState::Deleted);
        }

        assert_eq!(post.count_deleted(), 20);

        Ok(())
    }
}