Scheduling & Auto-Publishing

// Google Sheet columns:
// | Date       | Topic               | Platform  | Time  | Status    |
// | 2025-07-14 | AI Video Trends     | YouTube   | 14:00 | pending   |
// | 2025-07-14 | Quick AI Tips #42   | TikTok    | 09:00 | pending   |
// | 2025-07-14 | AI Video Trends     | Instagram | 18:00 | pending   |

const getCalendarEntries = async (date) => {
  const sheets = google.sheets({ version: 'v4', auth });
  const response = await sheets.spreadsheets.values.get({
    spreadsheetId: SHEET_ID,
    range: 'Calendar!A:E'
  });
  const rows = response.data.values;
  return rows
    .filter(row => row[0] === date && row[4] === 'pending')
    .map(row => ({
      date: row[0],
      topic: row[1],
      platform: row[2],
      time: row[3],
      status: row[4]
    }));
};

const uploadToYouTube = async (videoFile, thumbnailFile, metadata) => {
  const youtube = google.youtube({ version: 'v3', auth: oauthClient });

  // Step 1: Upload the video
  const videoResponse = await youtube.videos.insert({
    part: 'snippet,status,contentDetails',
    requestBody: {
      snippet: {
        title: metadata.title,           // Max 100 characters
        description: metadata.description, // Max 5000 characters
        tags: metadata.tags,              // Array of strings
        categoryId: '28',                 // Science & Technology
        defaultLanguage: 'en',
        defaultAudioLanguage: 'en'
      },
      status: {
        privacyStatus: 'private',         // Start private, schedule public
        publishAt: metadata.publishAt,     // ISO 8601: '2025-07-14T14:00:00Z'
        selfDeclaredMadeForKids: false,
        license: 'youtube',
        embeddable: true
      }
    },
    media: {
      body: fs.createReadStream(videoFile)
    }
  });

  const videoId = videoResponse.data.id;

  // Step 2: Set custom thumbnail
  await youtube.thumbnails.set({
    videoId: videoId,
    media: {
      body: fs.createReadStream(thumbnailFile)
    }
  });

  // Step 3: Add to playlist
  await youtube.playlistItems.insert({
    part: 'snippet',
    requestBody: {
      snippet: {
        playlistId: metadata.playlistId,
        resourceId: {
          kind: 'youtube#video',
          videoId: videoId
        }
      }
    }
  });

  return { videoId, url: `https://youtube.com/watch?v=${videoId}` };
};

// Step 1: Initialize the upload
const initResponse = await fetch('https://open.tiktokapis.com/v2/post/publish/video/init/', {
  method: 'POST',
  headers: {
    'Authorization': `Bearer ${TIKTOK_ACCESS_TOKEN}`,
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    post_info: {
      title: 'AI Video Generation Tips #aitools #ai',
      privacy_level: 'PUBLIC_TO_EVERYONE',
      disable_duet: false,
      disable_comment: false,
      disable_stitch: false
    },
    source_info: {
      source: 'FILE_UPLOAD',
      video_size: fileSize,
      chunk_size: fileSize,
      total_chunk_count: 1
    }
  })
});

const { upload_url, publish_id } = await initResponse.json();

// Step 2: Upload the video file
await fetch(upload_url, {
  method: 'PUT',
  headers: {
    'Content-Range': `bytes 0-${fileSize - 1}/${fileSize}`,
    'Content-Type': 'video/mp4'
  },
  body: fs.createReadStream(videoPath)
});

// Step 3: Check publish status
const statusResponse = await fetch(
  `https://open.tiktokapis.com/v2/post/publish/status/fetch/`,
  {
    method: 'POST',
    headers: { 'Authorization': `Bearer ${TIKTOK_ACCESS_TOKEN}` },
    body: JSON.stringify({ publish_id })
  }
);

// Step 1: Create media container (video must be at a public URL)
const containerResponse = await fetch(
  `https://graph.facebook.com/v18.0/${IG_USER_ID}/media`,
  {
    method: 'POST',
    body: new URLSearchParams({
      media_type: 'REELS',
      video_url: publicVideoUrl,
      caption: 'How AI generates videos automatically! #aiautomation #aivideo',
      share_to_feed: 'true',
      access_token: IG_ACCESS_TOKEN
    })
  }
);
const { id: containerId } = await containerResponse.json();

// Step 2: Wait for processing (poll status)
let status = 'IN_PROGRESS';
while (status === 'IN_PROGRESS') {
  await sleep(10000);
  const check = await fetch(
    `https://graph.facebook.com/v18.0/${containerId}?fields=status_code&access_token=${IG_ACCESS_TOKEN}`
  );
  status = (await check.json()).status_code;
}

// Step 3: Publish
await fetch(
  `https://graph.facebook.com/v18.0/${IG_USER_ID}/media_publish`,
  {
    method: 'POST',
    body: new URLSearchParams({
      creation_id: containerId,
      access_token: IG_ACCESS_TOKEN
    })
  }
);

const generateMetadata = async (script, platform) => {
  const response = await openai.chat.completions.create({
    model: 'gpt-4',
    messages: [
      {
        role: 'system',
        content: `You are a ${platform} SEO expert. Generate optimized metadata for a video based on its script. Return JSON with: title (max 100 chars), description (max 5000 chars for YouTube, 2200 for Instagram), tags (array of 15-30 keywords), hashtags (array of 5-10 for social platforms).`
      },
      {
        role: 'user',
        content: `Platform: ${platform}\nScript:\n${script}`
      }
    ],
    response_format: { type: 'json_object' }
  });
  return JSON.parse(response.choices[0].message.content);
};

// Generate platform-specific metadata
const ytMeta = await generateMetadata(script, 'YouTube');
const tiktokMeta = await generateMetadata(script, 'TikTok');
const igMeta = await generateMetadata(script, 'Instagram Reels');

const generateThumbnail = async (videoTitle, keyFrame) => {
  // Step 1: Generate background image with DALL-E
  const bgImage = await openai.images.generate({
    model: 'dall-e-3',
    prompt: `YouTube thumbnail background: ${videoTitle}. Bold, vibrant, high-contrast, eye-catching, no text. 16:9 aspect ratio.`,
    size: '1792x1024',
    quality: 'hd'
  });

  // Step 2: Generate click-worthy title text with GPT
  const titleText = await openai.chat.completions.create({
    model: 'gpt-4',
    messages: [{
      role: 'user',
      content: `Write a SHORT (3-5 words max) YouTube thumbnail text for: "${videoTitle}". Make it dramatic, curiosity-driven. Examples: "This Changes Everything", "AI Can Do WHAT?", "You Won't Believe This"`
    }]
  });

  // Step 3: Overlay text on image using Sharp + Canvas
  const thumbnail = await sharp(bgImageBuffer)
    .composite([
      { input: textOverlayBuffer, gravity: 'center' },
      { input: brandLogoBuffer, gravity: 'southeast' }
    ])
    .resize(1280, 720)   // YouTube thumbnail standard size
    .jpeg({ quality: 95 })
    .toBuffer();

  return thumbnail;
};