import sharp from 'sharp';
import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

async function generateFavicon() {
	const sourceIcon = path.join(__dirname, '..', 'static', 'icon-source.png');
	const outputIcon = path.join(__dirname, '..', 'static', 'favicon.png');

	console.log('Generating favicon.png from icon-source.png...');

	// Verify source file exists
	if (!fs.existsSync(sourceIcon)) {
		console.error('Error: icon-source.png not found at', sourceIcon);
		process.exit(1);
	}

	// Resize to 192x192 with transparent background
	await sharp(sourceIcon)
		.resize(192, 192, {
			fit: 'contain',
			background: { r: 0, g: 0, b: 0, alpha: 0 }
		})
		.ensureAlpha()
		.png()
		.toFile(outputIcon);

	// Verify output file
	const metadata = await sharp(outputIcon).metadata();
	const stats = fs.statSync(outputIcon);

	console.log(`✓ favicon.png generated successfully`);
	console.log(`  Dimensions: ${metadata.width}x${metadata.height}`);
	console.log(`  Format: ${metadata.format}`);
	console.log(`  Size: ${(stats.size / 1024).toFixed(1)}KB`);

	// Validate success criteria
	if (metadata.width !== 192 || metadata.height !== 192) {
		console.error('Error: Invalid dimensions');
		process.exit(1);
	}
	if (metadata.format !== 'png') {
		console.error('Error: Invalid format');
		process.exit(1);
	}
	if (stats.size > 100 * 1024) {
		console.error('Error: File size exceeds 100KB');
		process.exit(1);
	}

	console.log('✓ All validation checks passed');
}

generateFavicon().catch((err) => {
	console.error('Error generating favicon:', err);
	process.exit(1);
});