import { ApiClientBound } from '../decorators';
import { API_ENDPOINTS } from './common';
import type {
  UploadChunkRequest,
  UploadChunkResponse,
  MergeChunksRequest,
  MergeChunksResponse,
  CheckUploadStatusRequest,
  CheckUploadStatusResponse
} from '../types/upload/api';
import type { AxiosHttpClient } from '../client';

/**
 * 上传API服务类
 * 使用自定义实现而非@Request装饰器，以支持分片上传的复杂headers
 */
@ApiClientBound
export class UploadApiService {
  /**
   * 客户端实例，由ApiClientBound装饰器注入
   */
  declare client: AxiosHttpClient;

  /**
   * 上传文件分片
   * @param chunkRequest 分片上传请求参数
   * @param chunkBlob 文件分片数据
   * @returns 分片上传响应
   */
  async uploadChunk(
    chunkRequest: UploadChunkRequest,
    chunkBlob: Blob
  ): Promise<UploadChunkResponse> {
    // 创建FormData以支持文件上传
    const formData = new FormData();
    formData.append('chunk', chunkBlob);
    formData.append('chunkIndex', chunkRequest.chunkIndex.toString());
    formData.append('totalChunks', chunkRequest.totalChunks.toString());
    formData.append('fileName', chunkRequest.fileName);
    formData.append('fileType', chunkRequest.fileType);
    formData.append('fileId', chunkRequest.fileId);

    // 自定义headers，不设置Content-Type，让浏览器自动设置multipart/form-data
    const headers = {
      'X-Chunk-Index': chunkRequest.chunkIndex.toString(),
      'X-Total-Chunks': chunkRequest.totalChunks.toString(),
      'X-File-Id': chunkRequest.fileId,
      'X-Chunk-Size': chunkRequest.chunkSize.toString(),
      'X-Total-Size': chunkRequest.totalSize.toString(),
      // 不设置Content-Type，让浏览器自动处理
    };

    // 直接使用client实例发送请求，而不通过@Request装饰器
    return await this.client.request({
      method: 'POST',
      url: API_ENDPOINTS.UPLOAD_CHUNK,
      body: formData,
      headers,
      // 允许跨域携带凭证
      withCredentials: true,
      // 禁用默认的Content-Type设置（禁止axios的jsonify处理）
      transformRequest: [(data: any) => data]
    });
  }

  /**
   * 合并文件分片
   * @param mergeRequest 合并分片请求参数
   * @returns 合并分片响应
   */
  async mergeChunks(mergeRequest: MergeChunksRequest): Promise<MergeChunksResponse> {
    const headers = {
      'Content-Type': 'application/json',
      'X-File-Id': mergeRequest.fileId,
      'X-Total-Chunks': mergeRequest.totalChunks.toString()
    };

    return await this.client.request({
      method: 'POST',
      url: API_ENDPOINTS.MERGE_CHUNKS,
      body: mergeRequest,
      headers,
      withCredentials: true
    });
  }

  /**
   * 检查文件上传状态
   * @param checkRequest 检查上传状态请求参数
   * @returns 上传状态响应
   */
  async checkUploadStatus(
    checkRequest: CheckUploadStatusRequest
  ): Promise<CheckUploadStatusResponse> {
    const headers = {
      'X-File-Id': checkRequest.fileId
    };

    return await this.client.request({
      method: 'POST',
      url: API_ENDPOINTS.CHECK_UPLOAD_STATUS,
      body: checkRequest,
      headers,
      withCredentials: true
    });
  }

  /**
   * 生成文件唯一ID
   * @param _fileName 文件名（未使用，保留参数位置）
   * @param fileSize 文件大小
   * @returns 文件唯一ID
   */
  generateFileId(_fileName: string, fileSize: number): string {
    const timestamp = Date.now().toString(36);
    const random = Math.random().toString(36).substring(2, 9);
    return `${timestamp}_${random}_${fileSize}`;
  }

  /**
   * 计算分片数量
   * @param fileSize 文件大小
   * @param chunkSize 分片大小
   * @returns 分片数量
   */
  calculateChunks(fileSize: number, chunkSize: number = 5 * 1024 * 1024): number {
    return Math.ceil(fileSize / chunkSize);
  }
}

// 导出单例实例
export const uploadApi = new UploadApiService();