//
//  EPImageUploader.swift
//  YuMi
//
//  Created by AI on 2025-10-11.
//

import UIKit
import Foundation

/// 图片批量上传工具（纯 Swift 内部类，直接使用 QCloudCOSXML SDK）
/// 不对外暴露，由 EPSDKManager 内部调用
class EPImageUploader {
    
    init() {}
    
    /// 批量上传图片（内部方法）
    /// - Parameters:
    ///   - images: 要上传的图片数组
    ///   - bucket: QCloud bucket 名称
    ///   - customDomain: 自定义域名
    ///   - progress: 进度回调 (已上传数, 总数)
    ///   - success: 成功回调
    ///   - failure: 失败回调
    func performBatchUpload(
        _ images: [UIImage],
        bucket: String,
        customDomain: String,
        progress: @escaping (Int, Int) -> Void,
        success: @escaping ([[String: Any]]) -> Void,
        failure: @escaping (String) -> Void
    ) {
        let total = images.count
        let queue = DispatchQueue(label: "com.yumi.imageupload", attributes: .concurrent)
        let semaphore = DispatchSemaphore(value: 3) // 最多同时上传 3 张
        var uploadedCount = 0
        var resultList: [[String: Any]] = []
        var hasError = false
        let lock = NSLock()
        
        for (_, image) in images.enumerated() {
            queue.async {
                semaphore.wait()
                
                // 检查是否已经失败
                lock.lock()
                if hasError {
                    lock.unlock()
                    semaphore.signal()
                    return
                }
                lock.unlock()
                
                // 压缩图片
                guard let imageData = image.jpegData(compressionQuality: 0.5) else {
                    lock.lock()
                    hasError = true
                    lock.unlock()
                    semaphore.signal()
                    DispatchQueue.main.async {
                        failure(YMLocalizedString("error.image_compress_failed"))
                    }
                    return
                }
                
                // 获取图片格式
                let format = UIImage.getImageType(withImageData: imageData) ?? "jpeg"
                
                // 生成文件名
                let uuid = NSString.createUUID()
                let fileName = "image/\(uuid).\(format)"
                
                // 直接使用 QCloud SDK 上传
                let request = QCloudCOSXMLUploadObjectRequest<AnyObject>()
                request.bucket = bucket
                request.object = fileName
                request.body = imageData as NSData
                
                // 监听上传进度（可选）
                request.sendProcessBlock = { bytesSent, totalBytesSent, totalBytesExpectedToSend in
                    // 单个文件的上传进度（当前不使用）
                }
                
                // 监听上传结果
                request.finishBlock = { [weak self] result, error in
                    guard let self = self else {
                        semaphore.signal()
                        return
                    }
                    
                    if let error = error {
                        // 上传失败
                        lock.lock()
                        if !hasError {
                            hasError = true
                            lock.unlock()
                            semaphore.signal()
                            DispatchQueue.main.async {
                                failure(error.localizedDescription)
                            }
                        } else {
                            lock.unlock()
                            semaphore.signal()
                        }
                    } else if let result = result as? QCloudUploadObjectResult {
                        // 上传成功
                        lock.lock()
                        if !hasError {
                            uploadedCount += 1
                            
                            // 解析上传 URL（参考 UploadFile.m line 217-223）
                            let uploadedURL = self.parseUploadURL(result.location, customDomain: customDomain)
                            
                            let imageInfo: [String: Any] = [
                                "resUrl": uploadedURL,
                                "width": image.size.width,
                                "height": image.size.height,
                                "format": format
                            ]
                            resultList.append(imageInfo)
                            
                            let currentUploaded = uploadedCount
                            lock.unlock()
                            
                            // 进度回调
                            DispatchQueue.main.async {
                                progress(currentUploaded, total)
                            }
                            
                            // 全部完成
                            if currentUploaded == total {
                                DispatchQueue.main.async {
                                    success(resultList)
                                }
                            }
                        } else {
                            lock.unlock()
                        }
                        semaphore.signal()
                    } else {
                        semaphore.signal()
                    }
                }
                
                // 执行上传
                QCloudCOSTransferMangerService.defaultCOSTransferManager().uploadObject(request)
            }
        }
    }
    
    /// 解析上传返回的 URL（参考 UploadFile.m line 217-223）
    /// - Parameters:
    ///   - location: QCloud 返回的原始 URL
    ///   - customDomain: 自定义域名
    /// - Returns: 解析后的 URL
    private func parseUploadURL(_ location: String, customDomain: String) -> String {
        let components = location.components(separatedBy: ".com/")
        if components.count == 2 {
            return "\(customDomain)/\(components[1])"
        }
        return location
    }
}