#!/usr/bin/env node
/**
 * Logo URL Validator
 * Validates that all logoURI URLs are accessible and return image content
 */

import { readFileSync, existsSync, statSync } from 'fs';
import { fileURLToPath } from 'url';
import { dirname, resolve } from 'path';

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);
const PROJECT_ROOT = resolve(__dirname, '../..');

const MAX_LOGO_SIZE = 500 * 1024; // 500KB
const IMAGE_MIME_TYPES = ['image/png', 'image/jpeg', 'image/jpg', 'image/svg+xml', 'image/webp', 'image/gif'];

function inferContentTypeFromPath(filePath) {
  if (filePath.endsWith('.svg')) return 'image/svg+xml';
  if (filePath.endsWith('.png')) return 'image/png';
  if (filePath.endsWith('.jpg') || filePath.endsWith('.jpeg')) return 'image/jpeg';
  if (filePath.endsWith('.webp')) return 'image/webp';
  if (filePath.endsWith('.gif')) return 'image/gif';
  return null;
}

function resolveLocalRepoAsset(logoURI) {
  try {
    const url = new URL(logoURI);
    if (url.protocol !== 'https:') return null;

    if (url.hostname === 'raw.githubusercontent.com') {
      const segments = url.pathname.split('/').filter(Boolean);
      if (segments.length < 4) return null;
      const relativePath = segments.slice(3).join('/');
      const candidate = resolve(PROJECT_ROOT, relativePath);
      return existsSync(candidate) ? candidate : null;
    }

    if (url.hostname === 'gitea.d-bis.org') {
      const marker = '/raw/branch/';
      const markerIndex = url.pathname.indexOf(marker);
      if (markerIndex === -1) return null;
      const afterMarker = url.pathname.slice(markerIndex + marker.length);
      const pathSegments = afterMarker.split('/').filter(Boolean);
      if (pathSegments.length < 2) return null;
      const relativePath = pathSegments.slice(1).join('/');
      const candidate = resolve(PROJECT_ROOT, relativePath);
      return existsSync(candidate) ? candidate : null;
    }
  } catch {
    return null;
  }

  return null;
}

async function validateLogo(logoURI, tokenInfo) {
  const issues = [];

  // Check protocol
  if (!logoURI.startsWith('https://') && !logoURI.startsWith('ipfs://')) {
    issues.push(`URL should use HTTPS or IPFS (got: ${logoURI.substring(0, 20)}...)`);
  }

  // For HTTPS URLs, validate accessibility
  if (logoURI.startsWith('https://')) {
    const localAsset = resolveLocalRepoAsset(logoURI);
    if (localAsset) {
      try {
        const size = statSync(localAsset).size;
        const contentType = inferContentTypeFromPath(localAsset);
        if (!contentType || !IMAGE_MIME_TYPES.includes(contentType)) {
          issues.push(`Local repo asset has unsupported extension: ${localAsset}`);
        }
        if (size > MAX_LOGO_SIZE) {
          issues.push(`Local repo asset too large: ${(size / 1024).toFixed(2)}KB (max ${MAX_LOGO_SIZE / 1024}KB)`);
        }
        return issues;
      } catch (error) {
        issues.push(`Failed to stat local repo asset: ${error.message}`);
        return issues;
      }
    }

    try {
      const response = await fetch(logoURI, { method: 'HEAD' });
      
      if (!response.ok) {
        issues.push(`HTTP ${response.status}: ${response.statusText}`);
      } else {
        const contentType = response.headers.get('content-type');
        const contentLength = response.headers.get('content-length');
        
        if (contentType && !IMAGE_MIME_TYPES.some(mime => contentType.includes(mime))) {
          issues.push(`Invalid Content-Type: ${contentType} (expected image/*)`);
        }
        
        if (contentLength && parseInt(contentLength) > MAX_LOGO_SIZE) {
          issues.push(`Logo too large: ${(parseInt(contentLength) / 1024).toFixed(2)}KB (max ${MAX_LOGO_SIZE / 1024}KB)`);
        }
      }
    } catch (error) {
      issues.push(`Failed to fetch: ${error.message}`);
    }
  } else if (logoURI.startsWith('ipfs://')) {
    // IPFS URLs are valid but we can't easily validate them
    // Just check format
    if (!logoURI.match(/^ipfs:\/\/[a-zA-Z0-9]+/)) {
      issues.push('Invalid IPFS URL format');
    }
  }

  return issues;
}

async function validateLogos(filePath) {
  console.log(`\n🖼️  Validating logos in: ${filePath}\n`);

  // Read token list file
  let tokenList;
  try {
    const fileContent = readFileSync(filePath, 'utf-8');
    tokenList = JSON.parse(fileContent);
  } catch (error) {
    console.error('❌ Error reading or parsing token list file:');
    console.error(`   ${error.message}`);
    process.exit(1);
  }

  const results = [];
  let totalIssues = 0;

  // Validate top-level logoURI
  if (tokenList.logoURI) {
    console.log('Validating list logoURI...');
    const issues = await validateLogo(tokenList.logoURI, 'List');
    if (issues.length > 0) {
      results.push({ type: 'list', uri: tokenList.logoURI, issues });
      totalIssues += issues.length;
    }
  }

  // Validate token logos
  if (tokenList.tokens && Array.isArray(tokenList.tokens)) {
    for (const [index, token] of tokenList.tokens.entries()) {
      if (token.logoURI) {
        const tokenInfo = `${token.symbol || token.name} (Token[${index}])`;
        const issues = await validateLogo(token.logoURI, tokenInfo);
        if (issues.length > 0) {
          results.push({ type: 'token', token: tokenInfo, uri: token.logoURI, issues });
          totalIssues += issues.length;
        }
      }
    }
  }

  // Report results
  if (totalIssues === 0) {
    console.log('✅ All logos are valid!\n');
    return 0;
  }

  console.log(`Found ${totalIssues} logo issue(s):\n`);
  results.forEach(result => {
    if (result.type === 'list') {
      console.log(`❌ List logoURI: ${result.uri}`);
    } else {
      console.log(`❌ ${result.token}: ${result.uri}`);
    }
    result.issues.forEach(issue => {
      console.log(`   - ${issue}`);
    });
    console.log('');
  });

  return 1;
}

// Main
const filePath = process.argv[2] || resolve(__dirname, '../lists/dbis-138.tokenlist.json');

if (!filePath) {
  console.error('Usage: node validate-logos.js [path/to/token-list.json]');
  process.exit(1);
}

validateLogos(filePath).then(exitCode => {
  process.exit(exitCode);
}).catch(error => {
  console.error('Unexpected error:', error);
  process.exit(1);
});