import Foundation
import Logging

private let logger = Logger(label: "com.buckia.LocalStorageProvider")

/// Implementation of StorageProvider for local filesystem storage
public class LocalStorageProvider: StorageProvider {
    /// Provider type identifier
    public let providerType: StorageProviderType = .local
    
    /// Root directory for local storage
    private let rootDirectory: URL
    
    /// Creates a local storage provider with the specified configuration
    public init(config: BuckiaConfiguration) throws {
        guard config.provider == .local else {
            throw BuckiaError.configurationError("Invalid provider type for LocalStorageProvider")
        }
        
        // Use the user's Documents directory as the root
        self.rootDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
            .appendingPathComponent("BuckiaStorage")
            .appendingPathComponent(config.bucketName)
    }
    
    /// Connect to the storage provider
    public func connect() async throws -> Bool {
        // Ensure the root directory exists
        try FileManager.default.createDirectory(at: rootDirectory, withIntermediateDirectories: true)
        return true
    }
    
    /// Test connection to the provider
    public func testConnection() async throws -> ConnectionStatus {
        // Check if the root directory exists and is writable
        let isDirectory = try rootDirectory.checkResourceIsReachable()
        let isWritable = FileManager.default.isWritableFile(atPath: rootDirectory.path)
        
        return ConnectionStatus(
            isConnected: isDirectory && isWritable,
            details: [
                "directory_exists": isDirectory,
                "is_writable": isWritable
            ]
        )
    }
    
    /// Sync files between local and remote storage
    public func sync(options: SyncOptions, progressHandler: SyncProgressHandler?) async throws -> SyncResult {
        // Placeholder implementation
        return SyncResult()
    }
    
    /// Upload a file to remote storage
    public func uploadFile(localURL: URL, remotePath: String?) async throws -> UploadResult {
        let remoteURL = rootDirectory.appendingPathComponent(remotePath ?? localURL.lastPathComponent)
        
        // Create directory if needed
        try FileManager.default.createDirectory(at: remoteURL.deletingLastPathComponent(), withIntermediateDirectories: true)
        
        // Copy the file
        try FileManager.default.copyItem(at: localURL, to: remoteURL)
        
        return UploadResult(success: true, url: remoteURL)
    }
    
    /// Download a file from remote storage
    public func downloadFile(remotePath: String, localURL: URL) async throws -> DownloadResult {
        let remoteURL = rootDirectory.appendingPathComponent(remotePath)
        
        // Create directory if needed
        try FileManager.default.createDirectory(at: localURL.deletingLastPathComponent(), withIntermediateDirectories: true)
        
        // Copy the file
        try FileManager.default.copyItem(at: remoteURL, to: localURL)
        
        return DownloadResult(success: true, localURL: localURL)
    }
    
    /// Delete a file from remote storage
    public func deleteFile(remotePath: String) async throws -> Bool {
        let remoteURL = rootDirectory.appendingPathComponent(remotePath)
        
        if FileManager.default.fileExists(atPath: remoteURL.path) {
            try FileManager.default.removeItem(at: remoteURL)
            return true
        }
        
        return false
    }
    
    /// List files in remote storage
    public func listFiles(path: String?) async throws -> [RemoteFile] {
        let directoryURL = path != nil ? rootDirectory.appendingPathComponent(path!) : rootDirectory
        
        let fileURLs = try FileManager.default.contentsOfDirectory(at: directoryURL, includingPropertiesForKeys: [
            .fileSizeKey, .contentModificationDateKey, .typeIdentifierKey
        ])
        
        var remoteFiles: [RemoteFile] = []
        
        for fileURL in fileURLs {
            let relativePath = fileURL.path.replacingOccurrences(of: rootDirectory.path, with: "")
            let attributes = try fileURL.resourceValues(forKeys: [.fileSizeKey, .contentModificationDateKey, .typeIdentifierKey])
            
            remoteFiles.append(RemoteFile(
                path: relativePath,
                size: Int64(attributes.fileSize ?? 0),
                lastModified: attributes.contentModificationDate ?? Date(),
                contentType: attributes.typeIdentifier
            ))
        }
        
        return remoteFiles
    }
    
    /// Get a public URL for a file
    public func getPublicURL(remotePath: String) throws -> URL {
        return rootDirectory.appendingPathComponent(remotePath)
    }
    
    /// Generate tokens for access control
    public func generateAccessToken(options: AccessTokenOptions) throws -> String? {
        // Local storage doesn't need tokens, but we'll return a simple token for testing
        return "local_token_\(UUID().uuidString)"
    }
}