#!/usr/bin/env python3
"""Render Mermaid diagrams in markdown files to ASCII art."""

import re
import subprocess
import sys


def extract_mermaid_blocks(content: str) -> list[str]:
    """Extract mermaid blocks from markdown."""
    return re.findall(r"```mermaid\n(.*?)\n```", content, re.DOTALL)


def render_diagram(block: str) -> str:
    """Render a single mermaid block to ASCII."""
    result = subprocess.run(
        ["mermaid-ascii", "-f", "-"],
        input=block,
        capture_output=True,
        text=True,
    )
    if result.returncode != 0:
        return f"ERROR: {result.stderr}"
    return result.stdout


def main():
    if len(sys.argv) < 2:
        print("Usage: render-diagrams.py <markdown-file>")
        sys.exit(1)

    filename = sys.argv[1]
    content = open(filename).read()
    blocks = extract_mermaid_blocks(content)

    print(f"Found {len(blocks)} mermaid diagram(s) in {filename}")
    print()

    for i, block in enumerate(blocks):
        # Skip if empty
        if not block.strip():
            continue

        print(f"=== Diagram {i + 1} ===")
        print(render_diagram(block))


if __name__ == "__main__":
    main()