#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Mermaid Diagram Renderer
Finds mermaid code blocks in a markdown file and converts them to PNG images.
"""

import re
import subprocess
import os
import sys
from pathlib import Path

def check_mmdc():
    """Check if mermaid-cli (mmdc) is installed."""
    try:
        subprocess.run(['mmdc', '--version'], check=True, capture_output=True)
        return True
    except (subprocess.CalledProcessError, FileNotFoundError):
        print("❌ 'mermaid-cli' (mmdc) not found.")
        print("   Please install it globally by running: npm install -g @mermaid-js/mermaid-cli")
        print("   You need Node.js and npm installed first.")
        return False

def render_mermaid_diagrams(md_file_path, output_dir='charts'):
    """
    Renders all mermaid diagrams in a markdown file to PNG images.
    The markdown file is updated in-place to link to the generated images.
    """
    if not check_mmdc():
        return False

    md_path = Path(md_file_path)
    if not md_path.exists():
        print(f"❌ File not found: {md_file_path}")
        return False

    print(f"Processing Mermaid diagrams in: {md_path.name}")
    
    # Create charts directory if it doesn't exist
    charts_path = md_path.parent / output_dir
    charts_path.mkdir(exist_ok=True)

    with open(md_path, 'r', encoding='utf-8') as f:
        content = f.read()

    mermaid_blocks = re.findall(r'(```mermaid\n(.*?)\n```)', content, re.DOTALL)
    
    if not mermaid_blocks:
        print("No Mermaid diagrams found.")
        return True

    new_content = content
    for i, (block, code) in enumerate(mermaid_blocks):
        chart_filename = f"{md_path.stem}-mermaid-{i+1}.png"
        output_image_path = charts_path / chart_filename
        temp_mmd_path = charts_path / f"temp_{i}.mmd"

        # Write mermaid code to a temporary file
        with open(temp_mmd_path, 'w', encoding='utf-8') as f_temp:
            f_temp.write(code)

        # Run mmdc to convert to PNG
        try:
            cmd = [
                'mmdc',
                '-i', str(temp_mmd_path),
                '-o', str(output_image_path),
                '-b', 'transparent', # Transparent background
                '--configFile', 'mermaid_config.json'
            ]
            subprocess.run(cmd, check=True, capture_output=True)
            print(f"  ✅ Rendered {output_image_path.name}")

            # Replace the mermaid block with an image link
            image_link = f"![Mermaid Chart]({output_dir}/{chart_filename})"
            new_content = new_content.replace(block, image_link, 1)

        except subprocess.CalledProcessError as e:
            print(f"  ❌ Failed to render diagram {i+1}:")
            print(e.stderr.decode('utf-8', 'ignore'))
        finally:
            # Clean up temporary file
            if temp_mmd_path.exists():
                os.remove(temp_mmd_path)

    # Write the updated content back to the markdown file
    with open(md_path, 'w', encoding='utf-8') as f:
        f.write(new_content)
        
    print(f"Updated {md_path.name} with image links.")
    return True

def main():
    """Main function to process all specified markdown files."""
    markdown_files = [
        'rongzi_deepseek.md'
    ]
    
    all_successful = True
    for md_file in markdown_files:
        if not render_mermaid_diagrams(md_file):
            all_successful = False
    
    if not all_successful:
        sys.exit(1)

if __name__ == '__main__':
    # This allows running the script on its own to process all relevant files
    main()