import { NextResponse } from 'next/server';
import { requireRole } from '@/lib/auth';
import { db } from '@/lib/db';
import sharp from 'sharp';

export const maxDuration = 300; // 5 minutes for large migrations

async function convertToWebP(base64Data: string): Promise<string> {
  const matches = base64Data.match(/^data:image\/(\w+);base64,(.+)$/);
  if (!matches) {
    return base64Data;
  }

  const buffer = Buffer.from(matches[2], 'base64');
  const webpBuffer = await sharp(buffer)
    .webp({ quality: 90 })
    .toBuffer();

  return `data:image/webp;base64,${webpBuffer.toString('base64')}`;
}

export async function POST() {
  try {
    await requireRole('admin');

    console.log('Starting WebP migration...');

    const { rows: images } = await db.query(
      'SELECT id, filename, data, thumbnail, medium FROM images'
    );

    console.log(`Found ${images.length} images to process`);

    let converted = 0;
    let skipped = 0;
    let errors: number[] = [];
    let totalSavedKB = 0;

    for (const img of images) {
      try {
        let needsUpdate = false;
        const updates: { data?: string; thumbnail?: string; medium?: string } = {};

        if (img.data && !img.data.includes('image/webp')) {
          console.log(`Converting image ${img.id}: ${img.filename} (full)`);
          updates.data = await convertToWebP(img.data);
          needsUpdate = true;
        }

        if (img.thumbnail && !img.thumbnail.includes('image/webp')) {
          console.log(`Converting image ${img.id}: ${img.filename} (thumbnail)`);
          updates.thumbnail = await convertToWebP(img.thumbnail);
          needsUpdate = true;
        }

        if (img.medium && !img.medium.includes('image/webp')) {
          console.log(`Converting image ${img.id}: ${img.filename} (medium)`);
          updates.medium = await convertToWebP(img.medium);
          needsUpdate = true;
        }

        if (needsUpdate) {
          const oldSize = (img.data?.length || 0) + (img.thumbnail?.length || 0) + (img.medium?.length || 0);
          const newSize = (updates.data?.length || img.data?.length || 0) +
                          (updates.thumbnail?.length || img.thumbnail?.length || 0) +
                          (updates.medium?.length || img.medium?.length || 0);
          const savedKB = Math.round((oldSize - newSize) / 1024);
          totalSavedKB += savedKB;

          await db.query(
            'UPDATE images SET data = $1, thumbnail = $2, medium = $3 WHERE id = $4',
            [updates.data || img.data, updates.thumbnail || img.thumbnail, updates.medium || img.medium, img.id]
          );
          converted++;
        } else {
          skipped++;
        }
      } catch (err) {
        console.error(`Error processing image ${img.id}:`, err);
        errors.push(img.id);
      }
    }

    return NextResponse.json({
      success: true,
      total: images.length,
      converted,
      skipped,
      errors,
      totalSavedMB: Math.round(totalSavedKB / 1024 * 10) / 10,
    });
  } catch (error) {
    console.error('Migration error:', error);
    if ((error as Error).message === 'Unauthorized') {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
    }
    return NextResponse.json({ error: 'Migration failed', details: (error as Error).message }, { status: 500 });
  }
}

export async function GET() {
  try {
    await requireRole('admin');

    const { rows: images } = await db.query(
      'SELECT id, filename, LENGTH(data) as data_size, LENGTH(thumbnail) as thumb_size, LENGTH(medium) as medium_size FROM images'
    );

    let totalSize = 0;
    let webpCount = 0;
    let jpegCount = 0;

    for (const img of images) {
      totalSize += (img.data_size || 0) + (img.thumb_size || 0) + (img.medium_size || 0);
      if (img.data_size) {
        // We'd need to fetch the actual data to check format, so estimate based on size
      }
    }

    return NextResponse.json({
      totalImages: images.length,
      totalSizeKB: Math.round(totalSize / 1024),
      totalSizeMB: Math.round(totalSize / 1024 / 1024 * 10) / 10,
    });
  } catch (error) {
    if ((error as Error).message === 'Unauthorized') {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
    }
    return NextResponse.json({ error: 'Failed to get stats' }, { status: 500 });
  }
}