import Foundation

// MARK: - API Logger
@MainActor
class APILogger {
    enum LogLevel {
        case none
        case basic
        case detailed
    }
    
    #if DEBUG
    static var logLevel: LogLevel = .detailed
    #else
    static var logLevel: LogLevel = .none
    #endif
    
    private static let dateFormatter: DateFormatter = {
        let formatter = DateFormatter()
        formatter.dateFormat = "HH:mm:ss.SSS"
        return formatter
    }()
    
    // MARK: - Request Logging
    @MainActor static func logRequest<T: APIRequestProtocol>(
        _ request: T,
        url: URL,
        body: Data?,
        finalHeaders: [String: String]? = nil
    ) {
        #if DEBUG
        guard logLevel != .none else { return }
        #else
        return
        #endif
        
        let timestamp = dateFormatter.string(from: Date())
        
        print("\n🚀 [API Request] [\(timestamp)] ==================")
        print("📍 Endpoint: \(request.endpoint)")
        print("🔗 Full URL: \(url.absoluteString)")
        print("📝 Method: \(request.method.rawValue)")
        print("⏰ Timeout: \(request.timeout)s")
        
        // 显示最终的完整 headers（包括默认 headers 和自定义 headers）
        if let headers = finalHeaders, !headers.isEmpty {
            if logLevel == .detailed {
                print("📋 Final Headers (包括默认 + 自定义):")
                for (key, value) in headers.sorted(by: { $0.key < $1.key }) {
                    print("   \(key): \(value)")
                }
            } else if logLevel == .basic {
                print("📋 Headers: \(headers.count) 个 headers")
                // 只显示重要的 headers
                let importantHeaders = ["Content-Type", "Accept", "User-Agent", "Authorization"]
                for key in importantHeaders {
                    if let value = headers[key] {
                        print("   \(key): \(value)")
                    }
                }
            }
        } else if let customHeaders = request.headers, !customHeaders.isEmpty {
            print("📋 Custom Headers:")
            for (key, value) in customHeaders.sorted(by: { $0.key < $1.key }) {
                print("   \(key): \(value)")
            }
        } else {
            print("📋 Headers: 使用默认 headers")
        }
        
        if let queryParams = request.queryParameters, !queryParams.isEmpty {
            print("🔍 Query Parameters:")
            for (key, value) in queryParams.sorted(by: { $0.key < $1.key }) {
                print("   \(key): \(value)")
            }
        }
        
        if logLevel == .detailed {
            if let body = body {
                print("📦 Request Body (\(body.count) bytes):")
                if let jsonObject = try? JSONSerialization.jsonObject(with: body, options: []),
                   let prettyData = try? JSONSerialization.data(withJSONObject: jsonObject, options: .prettyPrinted),
                   let prettyString = String(data: prettyData, encoding: .utf8) {
                    print(prettyString)
                } else if let rawString = String(data: body, encoding: .utf8) {
                    print(rawString)
                } else {
                    print("Binary data")
                }
            } else {
                print("📦 Request Body: No body")
            }
            
            // 显示基础参数信息（仅详细模式）
            if request.includeBaseParameters {
                print("📱 Base Parameters: 自动注入设备和应用信息")
                let baseParams = BaseRequest()
                print("   Device: \(baseParams.model), OS: \(baseParams.os) \(baseParams.osVersion)")
                print("   App: \(baseParams.app) v\(baseParams.appVersion)")
                print("   Language: \(baseParams.acceptLanguage)")
            }
        } else if logLevel == .basic {
            if let body = body {
                print("📦 Request Body: \(formatBytes(body.count))")
            } else {
                print("📦 Request Body: No body")
            }
            
            // 基础模式也显示是否包含基础参数
            if request.includeBaseParameters {
                print("📱 Base Parameters: 已自动注入")
            }
        }
        
        print("=====================================")
    }
    
    // MARK: - Response Logging
    static func logResponse(data: Data, response: HTTPURLResponse, duration: TimeInterval) {
        #if DEBUG
        guard logLevel != .none else { return }
        #else
        return
        #endif
        
        let timestamp = dateFormatter.string(from: Date())
        let statusEmoji = response.statusCode < 400 ? "✅" : "❌"
        
        print("\n\(statusEmoji) [API Response] [\(timestamp)] ===================")
        print("⏱️  Duration: \(String(format: "%.3f", duration))s")
        print("📊 Status Code: \(response.statusCode)")
        print("🔗 URL: \(response.url?.absoluteString ?? "Unknown")")
        print("📏 Data Size: \(formatBytes(data.count))")
        
        if logLevel == .detailed {
            print("📋 Response Headers:")
            for (key, value) in response.allHeaderFields.sorted(by: { "\($0.key)" < "\($1.key)" }) {
                print("   \(key): \(value)")
            }
            
            print("📦 Response Data:")
            if data.isEmpty {
                print("   Empty response")
            } else if let jsonObject = try? JSONSerialization.jsonObject(with: data, options: []),
                      let prettyData = try? JSONSerialization.data(withJSONObject: jsonObject, options: .prettyPrinted),
                      let prettyString = String(data: prettyData, encoding: .utf8) {
                print(prettyString)
            } else if let rawString = String(data: data, encoding: .utf8) {
                print(rawString)
            } else {
                print("   Binary data (\(data.count) bytes)")
            }
        }
        
        print("=====================================")
    }
    
    // MARK: - Error Logging
    static func logError(_ error: Error, url: URL?, duration: TimeInterval) {
        #if DEBUG
        guard logLevel != .none else { return }
        #else
        return
        #endif
        
        let timestamp = dateFormatter.string(from: Date())
        
        print("\n❌ [API Error] [\(timestamp)] ======================")
        print("⏱️  Duration: \(String(format: "%.3f", duration))s")
        if let url = url {
            print("🔗 URL: \(url.absoluteString)")
        }
        
        if let apiError = error as? APIError {
            print("🚨 API Error: \(apiError.localizedDescription)")
        } else {
            print("🚨 System Error: \(error.localizedDescription)")
        }
        
        if logLevel == .detailed {
            if let urlError = error as? URLError {
                print("🔍 URLError Code: \(urlError.code.rawValue)")
                print("🔍 URLError Localized: \(urlError.localizedDescription)")
                
                // 详细的网络错误分析
                switch urlError.code {
                case .timedOut:
                    print("💡 建议：检查网络连接或增加超时时间")
                case .notConnectedToInternet:
                    print("💡 建议：检查网络连接")
                case .cannotConnectToHost:
                    print("💡 建议：检查服务器地址和端口")
                case .resourceUnavailable:
                    print("💡 建议：检查 API 端点是否正确")
                default:
                    break
                }
            }
            print("🔍 Full Error: \(error)")
        }
        
        print("=====================================\n")
    }
    
    // MARK: - Decoded Response Logging
    static func logDecodedResponse<T>(_ response: T, type: T.Type) {
        #if DEBUG
        guard logLevel == .detailed else { return }
        #else
        return
        #endif
        
        let timestamp = dateFormatter.string(from: Date())
        print("🎯 [Decoded Response] [\(timestamp)] Type: \(type)")
        print("=====================================\n")
    }
    
    // MARK: - Helper Methods
    private static func formatBytes(_ bytes: Int) -> String {
        let formatter = ByteCountFormatter()
        formatter.allowedUnits = [.useKB, .useMB]
        formatter.countStyle = .file
        return formatter.string(fromByteCount: Int64(bytes))
    }
    
    // MARK: - Performance Logging
    static func logPerformanceWarning(duration: TimeInterval, threshold: TimeInterval = 5.0) {
        #if DEBUG
        guard logLevel != .none && duration > threshold else { return }
        #else
        return
        #endif
        
        let timestamp = dateFormatter.string(from: Date())
        print("\n⚠️ [Performance Warning] [\(timestamp)] ============")
        print("🐌 Request took \(String(format: "%.3f", duration))s (threshold: \(threshold)s)")
        print("💡 建议：检查网络条件或优化 API 响应")
        print("================================================\n")
    }
}