#!/usr/bin/env python3
"""
Lighthouse Performance Audit Script
Runs Lighthouse audits on specified URLs and reports results
"""

import subprocess
import json
import sys
from pathlib import Path

def run_lighthouse(url, output_file=None):
    """Run Lighthouse audit on a URL"""
    cmd = [
        'npx', 'lighthouse', url,
        '--output=json',
        '--output-path=stdout',
        '--chrome-flags="--headless --no-sandbox"',
        '--quiet'
    ]

    try:
        result = subprocess.run(cmd, capture_output=True, text=True, timeout=60)
        if result.returncode != 0:
            print(f"Error running Lighthouse on {url}: {result.stderr}")
            return None

        data = json.loads(result.stdout)
        return data
    except subprocess.TimeoutExpired:
        print(f"Timeout running Lighthouse on {url}")
        return None
    except json.JSONDecodeError:
        print(f"Failed to parse Lighthouse output for {url}")
        return None
    except Exception as e:
        print(f"Unexpected error for {url}: {e}")
        return None

def extract_scores(lighthouse_data):
    """Extract key scores from Lighthouse data"""
    if not lighthouse_data or 'categories' not in lighthouse_data:
        return None

    categories = lighthouse_data['categories']
    return {
        'performance': int(categories.get('performance', {}).get('score', 0) * 100),
        'accessibility': int(categories.get('accessibility', {}).get('score', 0) * 100),
        'best-practices': int(categories.get('best-practices', {}).get('score', 0) * 100),
        'seo': int(categories.get('seo', {}).get('score', 0) * 100),
    }

def get_issues(lighthouse_data):
    """Extract issues from Lighthouse audit"""
    if not lighthouse_data or 'audits' not in lighthouse_data:
        return []

    issues = []
    audits = lighthouse_data['audits']

    # Key audits to check
    important_audits = [
        'first-contentful-paint',
        'largest-contentful-paint',
        'cumulative-layout-shift',
        'total-blocking-time',
        'speed-index',
        'interactive',
        'image-alt',
        'document-title',
        'meta-description',
        'link-text',
        'crawlable-anchors',
        'color-contrast',
        'tap-targets',
        'viewport',
        'uses-responsive-images',
        'modern-image-formats',
        'offscreen-images',
        'render-blocking-resources',
        'unminified-css',
        'unminified-javascript',
        'unused-css-rules',
        'unused-javascript',
    ]

    for audit_id in important_audits:
        if audit_id in audits:
            audit = audits[audit_id]
            if audit.get('score') is not None and audit['score'] < 0.9:
                issues.append({
                    'id': audit_id,
                    'title': audit.get('title', audit_id),
                    'score': audit.get('score'),
                    'displayValue': audit.get('displayValue', ''),
                    'description': audit.get('description', ''),
                })

    return issues

def main():
    if len(sys.argv) < 2:
        print("Usage: python lighthouse_audit.py <url>")
        sys.exit(1)

    url = sys.argv[1]
    print(f"\n🔍 Running Lighthouse audit on: {url}\n")

    data = run_lighthouse(url)
    if not data:
        print("❌ Failed to run Lighthouse audit")
        sys.exit(1)

    scores = extract_scores(data)
    if not scores:
        print("❌ Failed to extract scores")
        sys.exit(1)

    # Print results
    print("=" * 60)
    print("LIGHTHOUSE SCORES")
    print("=" * 60)

    for category, score in scores.items():
        emoji = "✅" if score >= 90 else "⚠️" if score >= 50 else "❌"
        print(f"{emoji} {category.upper():20s}: {score:3d}/100")

    print("\n" + "=" * 60)
    print("ISSUES FOUND")
    print("=" * 60 + "\n")

    issues = get_issues(data)
    if issues:
        for issue in issues[:10]:  # Show top 10 issues
            score_str = f"{int(issue['score'] * 100)}/100" if issue['score'] is not None else "N/A"
            print(f"⚠️  {issue['title']}")
            print(f"   Score: {score_str}")
            if issue['displayValue']:
                print(f"   Value: {issue['displayValue']}")
            print()
    else:
        print("✅ No major issues found!\n")

    # Check if all scores >= 90
    all_passed = all(score >= 90 for score in scores.values())
    if all_passed:
        print("🎉 All scores are 90+! Great job!\n")
        sys.exit(0)
    else:
        print("⚠️  Some scores are below 90. Review issues above.\n")
        sys.exit(1)

if __name__ == '__main__':
    main()