import { spawn } from 'node:child_process';

/**
 * Check if FFmpeg is available
 */
export async function checkFFmpeg(): Promise<boolean> {
  return new Promise((resolve) => {
    const proc = spawn('ffmpeg', ['-version']);
    proc.on('error', () => resolve(false));
    proc.on('close', (code) => resolve(code === 0));
  });
}

/**
 * Check if MP4Box is available
 */
export async function checkMP4Box(): Promise<boolean> {
  return new Promise((resolve) => {
    const proc = spawn('MP4Box', ['-version']);
    proc.on('error', () => resolve(false));
    proc.on('close', (code) => resolve(code === 0));
  });
}

/**
 * Check if NVENC is available
 */
export async function checkNvenc(): Promise<boolean> {
  return new Promise((resolve) => {
    const proc = spawn('ffmpeg', ['-hide_banner', '-encoders']);
    let output = '';
    
    proc.stdout.on('data', (data) => {
      output += data.toString();
    });
    
    proc.on('error', () => resolve(false));
    proc.on('close', (code) => {
      if (code !== 0) {
        resolve(false);
      } else {
        resolve(output.includes('h264_nvenc') || output.includes('hevc_nvenc'));
      }
    });
  });
}

/**
 * Execute FFmpeg command with progress tracking
 */
export async function execFFmpeg(
  args: string[],
  onProgress?: (percent: number) => void,
  duration?: number
): Promise<void> {
  return new Promise((resolve, reject) => {
    const proc = spawn('ffmpeg', args);

    let stderrData = '';

    proc.stderr.on('data', (data) => {
      const text = data.toString();
      stderrData += text;

      if (onProgress && duration) {
        // Parse time from FFmpeg output: time=00:01:23.45
        const timeMatch = text.match(/time=(\d{2}):(\d{2}):(\d{2}\.\d{2})/);
        if (timeMatch) {
          const hours = parseInt(timeMatch[1]);
          const minutes = parseInt(timeMatch[2]);
          const seconds = parseFloat(timeMatch[3]);
          const currentTime = hours * 3600 + minutes * 60 + seconds;
          const percent = Math.min(100, (currentTime / duration) * 100);
          onProgress(percent);
        }
      }
    });

    proc.on('error', (err) => {
      reject(new Error(`FFmpeg error: ${err.message}`));
    });

    proc.on('close', (code) => {
      if (code === 0) {
        resolve();
      } else {
        reject(new Error(`FFmpeg failed with exit code ${code}\n${stderrData}`));
      }
    });
  });
}

/**
 * Execute MP4Box command
 */
export async function execMP4Box(args: string[]): Promise<void> {
  return new Promise((resolve, reject) => {
    const proc = spawn('MP4Box', args);

    let stdoutData = '';
    let stderrData = '';

    proc.stdout.on('data', (data) => {
      stdoutData += data.toString();
    });

    proc.stderr.on('data', (data) => {
      stderrData += data.toString();
    });

    proc.on('error', (err) => {
      reject(new Error(`MP4Box error: ${err.message}`));
    });

    proc.on('close', (code) => {
      if (code === 0) {
        resolve();
      } else {
        const output = stderrData || stdoutData;
        reject(new Error(`MP4Box failed with exit code ${code}\n${output}`));
      }
    });
  });
}