import { statSync, existsSync, writeFileSync } from 'fs';
import path from 'path';
import type { VideoInfo } from './video';
import { fileTypeFromFile } from 'file-type';
import { platform } from 'node:os';
import { LogWrapper } from './log';
import { FFmpegAdapterFactory } from './ffmpeg-adapter-factory';
import type { IFFmpegAdapter } from './ffmpeg-adapter-interface';

const getFFmpegPath = (tool: string, binaryPath?: string): string => {
  if (process.platform === 'win32' && binaryPath) {
    const exeName = `${tool}.exe`;
    const localPath = path.join(binaryPath, 'ffmpeg', exeName);
    const isLocalExeExists = existsSync(localPath);
    return isLocalExeExists ? localPath : exeName;
  }
  return tool;
};

export let FFMPEG_CMD = 'ffmpeg';
export let FFPROBE_CMD = 'ffprobe';
export class FFmpegService {
  private static adapter: IFFmpegAdapter | null = null;
  private static initialized = false;

  /**
     * 初始化 FFmpeg 服务
     * @param binaryPath 二进制文件路径(来自 pathWrapper.binaryPath)
     * @param logger 日志记录器
     */
  public static async init (binaryPath: string, logger: LogWrapper): Promise<void> {
    if (this.initialized) {
      return;
    }

    // 检查本地 ffmpeg 路径
    FFMPEG_CMD = getFFmpegPath('ffmpeg', binaryPath);
    FFPROBE_CMD = getFFmpegPath('ffprobe', binaryPath);

    // 立即初始化适配器(会触发自动下载等逻辑)
    this.adapter = await FFmpegAdapterFactory.getAdapter(
      logger,
      FFMPEG_CMD,
      FFPROBE_CMD,
      binaryPath
    );

    this.initialized = true;
  }

  public static getAdapterName (): string {
    if (!this.adapter) {
      throw new Error('FFmpeg service not initialized. Please call FFmpegService.init() first.');
    }
    return this.adapter.name;

  }

  /**
     * 获取 FFmpeg 适配器
     */
  private static async getAdapter (): Promise<IFFmpegAdapter> {
    if (!this.adapter) {
      throw new Error('FFmpeg service not initialized. Please call FFmpegService.init() first.');
    }
    return this.adapter;
  }

  /**
     * 设置 FFmpeg 路径并更新适配器
     * @deprecated 建议使用 init() 方法初始化
     */
  public static async setFfmpegPath (ffmpegPath: string, logger: LogWrapper): Promise<void> {
    if (platform() === 'win32') {
      FFMPEG_CMD = path.join(ffmpegPath, 'ffmpeg.exe');
      FFPROBE_CMD = path.join(ffmpegPath, 'ffprobe.exe');
      logger.log('[Check] ffmpeg:', FFMPEG_CMD);
      logger.log('[Check] ffprobe:', FFPROBE_CMD);

      // 更新适配器路径
      await FFmpegAdapterFactory.updateFFmpegPath(logger, FFMPEG_CMD, FFPROBE_CMD);
    }
  }

  /**
     * 提取视频缩略图
     */
  public static async extractThumbnail (videoPath: string, thumbnailPath: string): Promise<void> {
    const adapter = await this.getAdapter();
    await adapter.extractThumbnail(videoPath, thumbnailPath);
  }

  /**
     * 转换音频文件
     */
  public static async convertFile (inputFile: string, outputFile: string, format: string): Promise<void> {
    const adapter = await this.getAdapter();
    await adapter.convertFile(inputFile, outputFile, format);
  }

  /**
     * 转换为 PCM 格式
     */
  public static async convert (filePath: string, pcmPath: string): Promise<{ result: boolean, sampleRate: number; }> {
    const adapter = await this.getAdapter();
    return adapter.convertToPCM(filePath, pcmPath);
  }

  /**
     * 获取视频信息
     */
  public static async getVideoInfo (videoPath: string, thumbnailPath: string): Promise<VideoInfo> {
    const adapter = await this.getAdapter();

    try {
      // 获取文件大小
      const fileSize = statSync(videoPath).size;

      // 使用适配器获取视频信息
      const videoInfo = await adapter.getVideoInfo(videoPath);

      // 如果提供了缩略图路径且适配器返回了缩略图,保存到指定路径
      if (thumbnailPath && videoInfo.thumbnail) {
        writeFileSync(thumbnailPath, videoInfo.thumbnail);
      }

      const result: VideoInfo = {
        width: videoInfo.width,
        height: videoInfo.height,
        time: videoInfo.duration,
        format: videoInfo.format,
        size: fileSize,
        filePath: videoPath,
      };

      return result;
    } catch (_error) {
      // 降级处理:返回默认值
      const fileType = await fileTypeFromFile(videoPath).catch(() => null);
      const fileSize = statSync(videoPath).size;

      return {
        width: 100,
        height: 100,
        time: 60,
        format: fileType?.ext ?? 'mp4',
        size: fileSize,
        filePath: videoPath,
      };
    }
  }
}