use std::collections::HashMap;
use std::path::{Path, PathBuf};
use std::sync::{Arc, Mutex};
use std::fs;
use serde::Deserialize;

use crate::collection::Collection;
use crate::error::{DocTreeError, Result};
use crate::storage::RedisStorage;
use crate::include::process_includes;
use crate::utils::name_fix;

/// Configuration for a collection from a .collection file
#[derive(Deserialize, Default, Debug)]
struct CollectionConfig {
    /// Optional name of the collection
    name: Option<String>,
    // Add other configuration options as needed
}

// Global variable to track the current collection name
// This is for compatibility with the Go implementation
lazy_static::lazy_static! {
    static ref CURRENT_COLLECTION_NAME: Arc<Mutex<Option<String>>> = Arc::new(Mutex::new(None));
}

// Global variable to track the current Collection
// This is for compatibility with the Go implementation

/// DocTree represents a manager for multiple collections
pub struct DocTree {
    /// Map of collections by name
    pub collections: HashMap<String, Collection>,
    
    /// Default collection name
    pub default_collection: Option<String>,
    
    /// Redis storage backend
    storage: RedisStorage,
    
    /// Name of the doctree (used as prefix for Redis keys)
    pub doctree_name: String,
    
    /// For backward compatibility
    pub name: String,
    
    /// For backward compatibility
    pub path: PathBuf,
}

/// Builder for DocTree
pub struct DocTreeBuilder {
    /// Map of collections by name
    collections: HashMap<String, Collection>,
    
    /// Default collection name
    default_collection: Option<String>,
    
    /// Redis storage backend
    storage: Option<RedisStorage>,
    
    /// Name of the doctree (used as prefix for Redis keys)
    doctree_name: Option<String>,
    
    /// For backward compatibility
    name: Option<String>,
    
    /// For backward compatibility
    path: Option<PathBuf>,
}

impl DocTree {
    /// Create a new DocTreeBuilder
    ///
    /// # Returns
    ///
    /// A new DocTreeBuilder
    pub fn builder() -> DocTreeBuilder {
        DocTreeBuilder {
            collections: HashMap::new(),
            default_collection: None,
            storage: None,
            doctree_name: Some("default".to_string()),
            name: None,
            path: None,
        }
    }
    
    /// Add a collection to the DocTree
    ///
    /// # Arguments
    ///
    /// * `path` - Base path of the collection
    /// * `name` - Name of the collection
    ///
    /// # Returns
    ///
    /// The added collection or an error
    pub fn add_collection<P: AsRef<Path>>(&mut self, path: P, name: &str) -> Result<&Collection> {
        // Create a new collection
        let namefixed = name_fix(name);
        // Clone the storage and set the doctree name
        let storage = self.storage.clone();
        storage.set_doctree_name(&self.doctree_name);
        
        let collection = Collection::builder(path, &namefixed)
            .with_storage(storage)
            .build()?;
        
        // Scan the collection
        collection.scan()?;
        
        // Add to the collections map
        self.collections.insert(collection.name.clone(), collection);
        
        // Return a reference to the added collection
        self.collections.get(&namefixed).ok_or_else(|| {
            DocTreeError::CollectionNotFound(namefixed.clone())
        })
    }
    
    /// Get a collection by name
    ///
    /// # Arguments
    ///
    /// * `name` - Name of the collection
    ///
    /// # Returns
    ///
    /// The collection or an error
    pub fn get_collection(&self, name: &str) -> Result<&Collection> {
        // For compatibility with tests, apply namefix
        let namefixed = name_fix(name);
        
        // Check if the collection exists
        self.collections.get(&namefixed).ok_or_else(|| {
            DocTreeError::CollectionNotFound(name.to_string())
        })
    }
    
    /// Delete a collection from the DocTree
    ///
    /// # Arguments
    ///
    /// * `name` - Name of the collection
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error
    pub fn delete_collection(&mut self, name: &str) -> Result<()> {
        // For compatibility with tests, apply namefix
        let namefixed = name_fix(name);
        
        // Check if the collection exists
        if !self.collections.contains_key(&namefixed) {
            return Err(DocTreeError::CollectionNotFound(name.to_string()));
        }
        
        // Delete from Redis
        self.storage.delete_collection(&namefixed)?;
        
        // Remove from the collections map
        self.collections.remove(&namefixed);
        
        Ok(())
    }
    
    /// Delete all collections from the DocTree and Redis
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error
    pub fn delete_all_collections(&mut self) -> Result<()> {
        // Delete all collections from Redis
        self.storage.delete_all_collections()?;
        
        // Clear the collections map
        self.collections.clear();
        
        // Reset the default collection
        self.default_collection = None;
        
        Ok(())
    }
    
    /// List all collections
    ///
    /// # Returns
    ///
    /// A vector of collection names
    pub fn list_collections(&self) -> Vec<String> {
        // First, try to get collections from the in-memory map
        let mut collections = self.collections.keys().cloned().collect::<Vec<String>>();
        
        // If no collections are found, try to get them from Redis
        if collections.is_empty() {
            // Get all collection keys from Redis
            if let Ok(keys) = self.storage.list_all_collections() {
                collections = keys;
            }
        }
        
        collections
    }
    
    /// Load a collection from Redis
    ///
    /// # Arguments
    ///
    /// * `name` - Name of the collection
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error
    pub fn load_collection(&mut self, name: &str) -> Result<()> {
        // Check if the collection exists in Redis
        if !self.storage.collection_exists(name)? {
            return Err(DocTreeError::CollectionNotFound(name.to_string()));
        }
        
        // Try to get the collection's path from Redis
        let path = match self.storage.get_collection_path(name) {
            Ok(path_str) => {
                println!("DEBUG: Found collection path in Redis: {}", path_str);
                PathBuf::from(path_str)
            },
            Err(e) => {
                println!("DEBUG: Could not retrieve collection path from Redis: {}", e);
                PathBuf::new() // Fallback to empty path if not found
            }
        };
        
        // Create a new collection
        let collection = Collection {
            path,
            name: name.to_string(),
            storage: self.storage.clone(),
        };
        
        // Add to the collections map
        self.collections.insert(name.to_string(), collection);
        
        Ok(())
    }
    
    /// Load all collections from Redis
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error
    pub fn load_collections_from_redis(&mut self) -> Result<()> {
        // Get all collection names from Redis
        let collections = self.storage.list_all_collections()?;
        
        // Load each collection
        for name in collections {
            // Skip if already loaded
            if self.collections.contains_key(&name) {
                continue;
            }
            
            // Try to get the collection's path from Redis
            let path = match self.storage.get_collection_path(&name) {
                Ok(path_str) => {
                    println!("DEBUG: Found collection path in Redis: {}", path_str);
                    PathBuf::from(path_str)
                },
                Err(e) => {
                    println!("DEBUG: Could not retrieve collection path from Redis: {}", e);
                    PathBuf::new() // Fallback to empty path if not found
                }
            };
            
            // Create a new collection
            let collection = Collection {
                path,
                name: name.clone(),
                storage: self.storage.clone(),
            };
            
            // Add to the collections map
            self.collections.insert(name, collection);
        }
        
        Ok(())
    }
    
    /// Get a page by name from a specific collection
    ///
    /// # Arguments
    ///
    /// * `collection_name` - Name of the collection (optional)
    /// * `page_name` - Name of the page
    ///
    /// # Returns
    ///
    /// The page content or an error
    pub fn page_get(&mut self, collection_name: Option<&str>, page_name: &str) -> Result<String> {
        let (collection_name, page_name) = self.resolve_collection_and_page(collection_name, page_name)?;
        
        // Get the collection
        let collection = self.get_collection(&collection_name)?;
        
        // Get the page content
        let content = collection.page_get(page_name)?;
        
        // Process includes
        let processed_content = process_includes(&content, &collection_name, self)?;
        
        Ok(processed_content)
    }
    
    /// Get a page by name from a specific collection and return its HTML content
    ///
    /// # Arguments
    ///
    /// * `collection_name` - Name of the collection (optional)
    /// * `page_name` - Name of the page
    ///
    /// # Returns
    ///
    /// The HTML content or an error
    pub fn page_get_html(&self, collection_name: Option<&str>, page_name: &str) -> Result<String> {
        let (collection_name, page_name) = self.resolve_collection_and_page(collection_name, page_name)?;
        
        // Get the collection
        let collection = self.get_collection(&collection_name)?;
        
        // Get the HTML
        collection.page_get_html(page_name, Some(self))
    }
    
    /// Get the URL for a file in a specific collection
    ///
    /// # Arguments
    ///
    /// * `collection_name` - Name of the collection (optional)
    /// * `file_name` - Name of the file
    ///
    /// # Returns
    ///
    /// The URL for the file or an error
    pub fn file_get_url(&self, collection_name: Option<&str>, file_name: &str) -> Result<String> {
        let (collection_name, file_name) = self.resolve_collection_and_page(collection_name, file_name)?;
        
        // Get the collection
        let collection = self.get_collection(&collection_name)?;
        
        // Get the URL
        collection.file_get_url(file_name)
    }
    
    /// Get the path to a page in the default collection
    ///
    /// # Arguments
    ///
    /// * `page_name` - Name of the page
    ///
    /// # Returns
    ///
    /// The path to the page or an error
    pub fn page_get_path(&self, page_name: &str) -> Result<String> {
        // Check if a default collection is set
        let default_collection = self.default_collection.as_ref().ok_or_else(|| {
            DocTreeError::NoDefaultCollection
        })?;
        
        // Get the collection
        let collection = self.get_collection(default_collection)?;
        
        // Get the path
        collection.page_get_path(page_name)
    }
    
    /// Get information about the DocTree
    ///
    /// # Returns
    ///
    /// A map of information
    pub fn info(&self) -> HashMap<String, String> {
        let mut info = HashMap::new();
        info.insert("name".to_string(), self.name.clone());
        info.insert("path".to_string(), self.path.to_string_lossy().to_string());
        info.insert("collections".to_string(), self.collections.len().to_string());
        info
    }
    
    /// Scan the default collection
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error
    pub fn scan(&self) -> Result<()> {
        // Check if a default collection is set
        let default_collection = self.default_collection.as_ref().ok_or_else(|| {
            DocTreeError::NoDefaultCollection
        })?;
        
        // Get the collection
        let collection = self.get_collection(default_collection)?;
        
        // Scan the collection
        collection.scan()
    }
    
    /// Resolve collection and page names
    ///
    /// # Arguments
    ///
    /// * `collection_name` - Name of the collection (optional)
    /// * `page_name` - Name of the page
    ///
    /// # Returns
    ///
    /// A tuple of (collection_name, page_name) or an error
    fn resolve_collection_and_page<'a>(&self, collection_name: Option<&'a str>, page_name: &'a str) -> Result<(String, &'a str)> {
        match collection_name {
            Some(name) => Ok((name_fix(name), page_name)),
            None => {
                // Use the default collection
                let default_collection = self.default_collection.as_ref().ok_or_else(|| {
                    DocTreeError::NoDefaultCollection
                })?;
                Ok((default_collection.clone(), page_name))
            }
        }
    }
    
    /// Recursively scan directories for .collection files and add them as collections
    ///
    /// # Arguments
    ///
    /// * `root_path` - The root path to start scanning from
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error
    pub fn scan_collections<P: AsRef<Path>>(&mut self, root_path: P) -> Result<()> {
        let root_path = root_path.as_ref();
        
        println!("DEBUG: Scanning for collections in directory: {:?}", root_path);
        
        // Walk through the directory tree
        for entry in walkdir::WalkDir::new(root_path).follow_links(true) {
            let entry = match entry {
                Ok(entry) => entry,
                Err(e) => {
                    eprintln!("Error walking directory: {}", e);
                    continue;
                }
            };
            
            // Skip directories and files that start with a dot (.)
            let file_name = entry.file_name().to_string_lossy();
            if file_name.starts_with(".") {
                continue;
            }
            
            // Skip non-directories
            if !entry.file_type().is_dir() {
                continue;
            }
            
            // Check if this directory contains a .collection file
            let collection_file_path = entry.path().join(".collection");
            if collection_file_path.exists() {
                // Found a collection directory
                println!("DEBUG: Found .collection file at: {:?}", collection_file_path);
                let dir_path = entry.path();
                
                // Get the directory name as a fallback collection name
                let dir_name = dir_path.file_name()
                    .and_then(|name| name.to_str())
                    .unwrap_or("unnamed");
                
                // Try to read and parse the .collection file
                let collection_name = match fs::read_to_string(&collection_file_path) {
                    Ok(content) => {
                        if content.trim().is_empty() {
                            // Empty file, use directory name (name_fixed)
                            dir_name.to_string()  // We'll apply name_fix later at line 372
                        } else {
                            // Parse as TOML
                            match toml::from_str::<CollectionConfig>(&content) {
                                Ok(config) => {
                                    // Use the name from config if available, otherwise use directory name
                                    config.name.unwrap_or_else(|| dir_name.to_string())
                                },
                                Err(e) => {
                                    eprintln!("Error parsing .collection file at {:?}: {}", collection_file_path, e);
                                    dir_name.to_string()
                                }
                            }
                        }
                    },
                    Err(e) => {
                        eprintln!("Error reading .collection file at {:?}: {}", collection_file_path, e);
                        dir_name.to_string()
                    }
                };
                
                // Apply name_fix to the collection name
                let namefixed_collection_name = name_fix(&collection_name);
                
                // Add the collection to the DocTree
                println!("DEBUG: Adding collection '{}' from directory {:?}", namefixed_collection_name, dir_path);
                match self.add_collection(dir_path, &namefixed_collection_name) {
                    Ok(collection) => {
                        println!("DEBUG: Successfully added collection '{}' from {:?}", namefixed_collection_name, dir_path);
                        println!("DEBUG: Collection stored in Redis key 'collections:{}'", collection.name);
                        
                        // Count documents and images
                        let docs = collection.page_list().unwrap_or_default();
                        let files = collection.file_list().unwrap_or_default();
                        let images = files.iter().filter(|f|
                            f.ends_with(".png") || f.ends_with(".jpg") ||
                            f.ends_with(".jpeg") || f.ends_with(".gif") ||
                            f.ends_with(".svg")
                        ).count();
                        
                        println!("DEBUG: Collection '{}' contains {} documents and {} images",
                                namefixed_collection_name, docs.len(), images);
                    },
                    Err(e) => {
                        eprintln!("Error adding collection '{}' from {:?}: {}", namefixed_collection_name, dir_path, e);
                    }
                }
            }
        }
        
        Ok(())
    }

    /// Exports all collections to IPFS, encrypting their files and generating CSV manifests.
    ///
    /// # Arguments
    ///
    /// * `output_dir` - The directory to save the output CSV files.
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error.
    pub async fn export_collections_to_ipfs<P: AsRef<Path>>(&self, output_dir: P) -> Result<()> {
        use tokio::fs;

        let output_dir = output_dir.as_ref();

        // Create the output directory if it doesn't exist
        fs::create_dir_all(output_dir).await.map_err(DocTreeError::IoError)?;

        for (name, collection) in &self.collections {
            let csv_file_path = output_dir.join(format!("{}.csv", name));
            println!("DEBUG: Exporting collection '{}' to IPFS and generating CSV at {:?}", name, csv_file_path);
            if let Err(e) = collection.export_to_ipfs(&csv_file_path) {
                eprintln!("Error exporting collection '{}': {}", name, e);
                // Continue with the next collection
            }
        }

        Ok(())
    }

    /// Exports a specific collection to IPFS synchronously, encrypting its files and generating a CSV manifest.
    ///
    /// # Arguments
    ///
    /// * `collection_name` - The name of the collection to export.
    /// * `output_csv_path` - The path to save the output CSV file.
    ///
    /// # Returns
    ///
    /// Ok(()) on success or an error.
    pub fn export_collection_to_ipfs(&self, collection_name: &str, output_csv_path: &Path) -> Result<()> {
        // Get the collection
        let collection = self.get_collection(collection_name)?;

        // Create a new tokio runtime and block on the async export function
        let csv_file_path = output_csv_path.join(format!("{}.csv", collection_name));
        collection.export_to_ipfs(&csv_file_path)?;

        Ok(())
    }
}

impl DocTreeBuilder {
    /// Set the storage backend
    ///
    /// # Arguments
    ///
    /// * `storage` - Redis storage backend
    ///
    /// # Returns
    ///
    /// Self for method chaining
    /// Set the doctree name
    ///
    /// # Arguments
    ///
    /// * `name` - Name of the doctree
    ///
    /// # Returns
    ///
    /// Self for method chaining
    pub fn with_doctree_name(mut self, name: &str) -> Self {
        self.doctree_name = Some(name.to_string());
        self
    }
    
    pub fn with_storage(mut self, storage: RedisStorage) -> Self {
        self.storage = Some(storage);
        self
    }
    
    /// Add a collection
    ///
    /// # Arguments
    ///
    /// * `path` - Base path of the collection
    /// * `name` - Name of the collection
    ///
    /// # Returns
    ///
    /// Self for method chaining or an error
    pub fn with_collection<P: AsRef<Path>>(mut self, path: P, name: &str) -> Result<Self> {
        // Ensure storage is set
        let storage = self.storage.as_ref().ok_or_else(|| {
            DocTreeError::MissingParameter("storage".to_string())
        })?;
        
        // Get the doctree name
        let doctree_name = self.doctree_name.clone().unwrap_or_else(|| "default".to_string());
        
        // Create a new collection
        let namefixed = name_fix(name);
        
        // Clone the storage and set the doctree name
        let storage_clone = storage.clone();
        storage_clone.set_doctree_name(&doctree_name);
        
        let collection = Collection::builder(path.as_ref(), &namefixed)
            .with_storage(storage_clone)
            .build()?;
        
        // Scan the collection
        collection.scan()?;
        
        // Add to the collections map
        self.collections.insert(collection.name.clone(), collection);
        
        // For backward compatibility
        if self.name.is_none() {
            self.name = Some(namefixed.clone());
        }
        if self.path.is_none() {
            self.path = Some(path.as_ref().to_path_buf());
        }
        
        Ok(self)
    }
    
    /// Set the default collection
    ///
    /// # Arguments
    ///
    /// * `name` - Name of the default collection
    ///
    /// # Returns
    ///
    /// Self for method chaining
    pub fn with_default_collection(mut self, name: &str) -> Self {
        self.default_collection = Some(name_fix(name));
        self
    }
    
    /// Scan for collections in the given root path
    ///
    /// # Arguments
    ///
    /// * `root_path` - The root path to scan for collections
    ///
    /// # Returns
    ///
    /// Self for method chaining or an error
    pub fn scan_collections<P: AsRef<Path>>(self, root_path: P) -> Result<Self> {
        // Ensure storage is set
        let storage = self.storage.as_ref().ok_or_else(|| {
            DocTreeError::MissingParameter("storage".to_string())
        })?;
        
        // Get the doctree name
        let doctree_name = self.doctree_name.clone().unwrap_or_else(|| "default".to_string());
        
        // Clone the storage and set the doctree name
        let storage_clone = storage.clone();
        storage_clone.set_doctree_name(&doctree_name);
        
        // Create a temporary DocTree to scan collections
        let mut temp_doctree = DocTree {
            collections: HashMap::new(),
            default_collection: None,
            storage: storage_clone,
            doctree_name: doctree_name,
            name: self.name.clone().unwrap_or_default(),
            path: self.path.clone().unwrap_or_else(|| PathBuf::from("")),
        };
        
        // Scan for collections
        temp_doctree.scan_collections(root_path)?;
        
        // Create a new builder with the scanned collections
        let mut new_builder = self;
        for (name, collection) in temp_doctree.collections {
            new_builder.collections.insert(name.clone(), collection);
            
            // If no default collection is set, use the first one found
            if new_builder.default_collection.is_none() {
                new_builder.default_collection = Some(name);
            }
        }
        
        Ok(new_builder)
    }
    
    /// Build the DocTree
    ///
    /// # Returns
    ///
    /// A new DocTree or an error
    pub fn build(self) -> Result<DocTree> {
        // Ensure storage is set
        let storage = self.storage.ok_or_else(|| {
            DocTreeError::MissingParameter("storage".to_string())
        })?;
        
        // Get the doctree name
        let doctree_name = self.doctree_name.unwrap_or_else(|| "default".to_string());
        
        // Set the doctree name in the storage
        let storage_clone = storage.clone();
        storage_clone.set_doctree_name(&doctree_name);
        
        // Create the DocTree
        let mut doctree = DocTree {
            collections: self.collections,
            default_collection: self.default_collection,
            storage: storage_clone,
            doctree_name,
            name: self.name.unwrap_or_default(),
            path: self.path.unwrap_or_else(|| PathBuf::from("")),
        };
        
        // Set the global current collection name if a default collection is set
        if let Some(default_collection) = &doctree.default_collection {
            let mut current_collection_name = CURRENT_COLLECTION_NAME.lock().unwrap();
            *current_collection_name = Some(default_collection.clone());
        }
        
        // Load all collections from Redis
        doctree.load_collections_from_redis()?;
        
        Ok(doctree)
    }
}


/// Create a new DocTree instance
///
/// For backward compatibility, it also accepts path and name parameters
/// to create a DocTree with a single collection
///
/// # Arguments
///
/// * `args` - Optional path and name for backward compatibility
///
/// # Returns
///
/// A new DocTree or an error
pub fn new<P: AsRef<Path>>(args: &[&str]) -> Result<DocTree> {
    let storage = RedisStorage::new("redis://localhost:6379")?;
    
    let mut builder = DocTree::builder().with_storage(storage);
    
    // If the first argument is a doctree name, use it
    if args.len() >= 1 && args[0].starts_with("--doctree=") {
        let doctree_name = args[0].trim_start_matches("--doctree=");
        builder = builder.with_doctree_name(doctree_name);
    }
    
    // For backward compatibility with existing code
    if args.len() == 2 {
        let path = args[0];
        let name = args[1];
        
        // Apply namefix for compatibility with tests
        let namefixed = name_fix(name);
        
        // Add the collection
        builder = builder.with_collection(path, &namefixed)?;
        
        // Set the default collection
        builder = builder.with_default_collection(&namefixed);
    }
    
    builder.build()
}

/// Create a new DocTree by scanning a directory for collections
///
/// # Arguments
///
/// * `root_path` - The root path to scan for collections
/// * `doctree_name` - Optional name for the doctree (default: "default")
///
/// # Returns
///
/// A new DocTree or an error
pub fn from_directory<P: AsRef<Path>>(root_path: P, doctree_name: Option<&str>) -> Result<DocTree> {
    let storage = RedisStorage::new("redis://localhost:6379")?;
    
    let mut builder = DocTree::builder().with_storage(storage);
    
    // Set the doctree name if provided
    if let Some(name) = doctree_name {
        builder = builder.with_doctree_name(name);
    }
    
    builder.scan_collections(root_path)?.build()
}