#!/usr/bin/env python3
"""
PPT Master - Examples Index Generator

Automatically scans the examples directory and generates a README.md index file.

Usage:
    python3 scripts/generate_examples_index.py
    python3 scripts/generate_examples_index.py examples
"""

import sys
from pathlib import Path
from datetime import datetime
from collections import defaultdict

from console_encoding import configure_utf8_stdio

configure_utf8_stdio()

try:
    from project_utils import find_all_projects, get_project_info, CANVAS_FORMATS
except ImportError:
    print("Error: Cannot import the project_utils module")
    print("Please ensure project_utils.py is in the same directory")
    sys.exit(1)


def generate_examples_index(examples_dir: str = 'examples') -> str:
    """
    Generate a README.md index for the examples directory

    Args:
        examples_dir: Path to the examples directory

    Returns:
        Generated README.md content
    """
    examples_path = Path(examples_dir)

    if not examples_path.exists():
        print(f"[ERROR] Directory not found: {examples_dir}")
        return ""

    print(f"[SCAN] Scanning directory: {examples_dir}")

    # Find all projects
    projects = find_all_projects(examples_dir)

    if not projects:
        print("[WARN] No projects found")
        return ""

    print(f"Found {len(projects)} project(s)")

    # Collect project information
    projects_info = []
    for project_path in projects:
        info = get_project_info(str(project_path))
        projects_info.append(info)

    # Sort by date (newest first)
    projects_info.sort(key=lambda x: x['date'], reverse=True)

    # Group by format
    by_format = defaultdict(list)
    for info in projects_info:
        by_format[info['format']].append(info)

    # Generate README content
    content = []
    content.append("# PPT Master Example Projects Index\n")
    content.append("> This file is auto-generated by `skills/ppt-master/scripts/generate_examples_index.py`\n")
    content.append(f"> Last updated: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}\n")

    # Overview statistics
    content.append("## [Stats] Overview\n")
    content.append(f"- **Total projects**: {len(projects_info)}")
    content.append(f"- **Canvas formats**: {len(by_format)} type(s)")

    total_svgs = sum(info['svg_count'] for info in projects_info)
    content.append(f"- **SVG files**: {total_svgs}")

    # Statistics by format
    content.append("\n### Format Distribution\n")
    for fmt_key in sorted(by_format.keys(), key=lambda x: len(by_format[x]), reverse=True):
        count = len(by_format[fmt_key])
        fmt_name = CANVAS_FORMATS.get(fmt_key, {}).get('name', fmt_key)
        content.append(f"- **{fmt_name}**: {count} project(s)")

    # Recently updated
    content.append("\n## [New] Recently Updated\n")
    for info in projects_info[:5]:
        content.append(
            f"- **{info['name']}** ({info['format_name']}) - {info['date_formatted']}")

    # Project list by format
    content.append("\n## [List] Project List\n")

    # Define format display order
    format_order = ['ppt169', 'ppt43', 'wechat',
                    'xiaohongshu', 'moments', 'story', 'banner', 'a4']

    for fmt_key in format_order:
        if fmt_key not in by_format:
            continue

        fmt_info = CANVAS_FORMATS.get(fmt_key, {})
        fmt_name = fmt_info.get('name', fmt_key)
        dimensions = fmt_info.get('dimensions', '')

        content.append(f"\n### {fmt_name} ({dimensions})\n")

        projects_list = by_format[fmt_key]
        # Sort by date
        projects_list.sort(key=lambda x: x['date'], reverse=True)

        for info in projects_list:
            # Project name and link
            project_link = f"./{info['dir_name']}"

            # Build project entry
            line = f"- **[{info['name']}]({project_link})**"

            # Add date
            line += f" - {info['date_formatted']}"

            # Add SVG count
            line += f" - {info['svg_count']} page(s)"

            content.append(line)

    # Other uncategorized formats
    other_formats = set(by_format.keys()) - set(format_order)
    if other_formats:
        content.append("\n### Other Formats\n")
        for fmt_key in sorted(other_formats):
            projects_list = by_format[fmt_key]
            for info in projects_list:
                project_link = f"./{info['dir_name']}"
                line = f"- **[{info['name']}]({project_link})**"
                line += f" ({info['format_name']}) - {info['date_formatted']}"
                line += f" - {info['svg_count']} page(s)"
                content.append(line)

    # Usage instructions
    content.append("\n## [Docs] Usage Instructions\n")
    content.append("### Preview Projects\n")
    content.append("Each project contains the following files:\n")
    content.append("- `README.md` - Project documentation")
    content.append("- `Design Spec & Content Outline.md` - Full design specification")
    content.append("- `svg_output/` - SVG output files\n")

    content.append("**Method 1: Using an HTTP server (recommended)**\n")
    content.append("```bash")
    content.append(
        "python3 -m http.server --directory examples/<project_name>/svg_output 8000")
    content.append("# Visit http://localhost:8000")
    content.append("```\n")

    content.append("**Method 2: Open SVG directly**\n")
    content.append("```bash")
    content.append(
        "open examples/<project_name>/svg_output/slide_01_cover.svg")
    content.append("```\n")

    # Create new project
    content.append("### Create a New Project\n")
    content.append("Refer to existing project structures, or use the project management tool:\n")
    content.append("```bash")
    content.append(
        "python3 scripts/project_manager.py init my_project --format ppt169")
    content.append("```\n")

    # Contribution guidelines
    content.append("## [Contribute] Contributing Example Projects\n")
    content.append("We welcome you to share your projects in the examples directory!\n")
    content.append("### Project Requirements\n")
    content.append("1. Follow the standard project structure")
    content.append("2. Include a complete README.md and design specification")
    content.append("3. SVG files must comply with technical specifications")
    content.append("4. Directory naming format: `{project_name}_{format}_{YYYYMMDD}`\n")

    content.append("### Submission Process\n")
    content.append("1. Create a project under the `examples/` directory")
    content.append(
        "2. Validate the project: `python3 scripts/project_manager.py validate examples/<project>`")
    content.append("3. Update the index: `python3 scripts/generate_examples_index.py`")
    content.append("4. Submit a Pull Request\n")

    # Related resources
    content.append("## [Resources] Related Resources\n")
    content.append("- [Quick Start](../README.md)")
    content.append("- [Workflow Tutorial](../../AGENTS.md)")
    content.append("- [Canvas Formats](../references/canvas-formats.md)")
    content.append("- [Role Definitions](../references/)")
    content.append("- [Chart Templates](../templates/charts/README.md)\n")

    # Footer
    content.append("---\n")
    content.append(
        f"*Auto-generated on {datetime.now().strftime('%Y-%m-%d %H:%M:%S')} by PPT Master*")

    return "\n".join(content)


def main() -> None:
    """Run the CLI entry point."""
    examples_dir = 'examples'

    if len(sys.argv) > 1:
        if sys.argv[1] in {'-h', '--help', 'help'}:
            print(__doc__)
            sys.exit(0)

        examples_dir = sys.argv[1]

    print("=" * 80)
    print("PPT Master - Examples Index Generator")
    print("=" * 80 + "\n")

    # Generate index content
    content = generate_examples_index(examples_dir)

    if not content:
        print("\n[ERROR] Generation failed")
        sys.exit(1)

    # Write to file
    output_file = Path(examples_dir) / 'README.md'

    try:
        with open(output_file, 'w', encoding='utf-8') as f:
            f.write(content)

        print(f"\n[OK] Index file generated: {output_file}")
        print(f"   Contains {len(content.splitlines())} lines")

        # Display statistics
        projects_count = content.count('- **[')
        print(f"   Indexed {projects_count} project(s)")

    except Exception as e:
        print(f"\n[ERROR] Failed to write file: {e}")
        sys.exit(1)


if __name__ == '__main__':
    main()