#!/usr/bin/env python3
"""Compile every standalone C++ fenced block in course Markdown files."""

from __future__ import annotations

import re
import subprocess
import sys
import tempfile
from pathlib import Path


def main() -> int:
    root = Path(sys.argv[1] if len(sys.argv) > 1 else "课程")
    documents = sorted(root.rglob("*.md"))
    failed = 0
    compiled = 0
    snippets = 0
    with tempfile.TemporaryDirectory(prefix="course-cpp-") as temp:
        directory = Path(temp)
        for source in sorted(Path("参考实现").rglob("*.cpp")):
            compiled += 1
            output = directory / f"attachment-{compiled}"
            result = subprocess.run(
                [
                    "g++",
                    "-std=c++17",
                    "-Wall",
                    "-Wextra",
                    "-Wpedantic",
                    str(source),
                    "-o",
                    str(output),
                ],
                text=True,
                capture_output=True,
                check=False,
            )
            if result.returncode != 0:
                failed += 1
                print(f"FAIL {source}", file=sys.stderr)
                print(result.stderr, file=sys.stderr)
        for document in documents:
            text = document.read_text(encoding="utf-8")
            blocks = re.findall(r"```(?:cpp|c\+\+)\n(.*?)```", text, flags=re.DOTALL)
            for index, code in enumerate(blocks, 1):
                if not re.search(r"\bint\s+main\s*\(", code):
                    snippets += 1
                    continue
                compiled += 1
                source = directory / f"block-{compiled}.cpp"
                output = directory / f"block-{compiled}"
                source.write_text(code, encoding="utf-8")
                result = subprocess.run(
                    [
                        "g++",
                        "-std=c++17",
                        "-Wall",
                        "-Wextra",
                        "-Wpedantic",
                        str(source),
                        "-o",
                        str(output),
                    ],
                    text=True,
                    capture_output=True,
                    check=False,
                )
                if result.returncode != 0:
                    failed += 1
                    print(f"FAIL {document}:{index}", file=sys.stderr)
                    print(result.stderr, file=sys.stderr)
    print(f"compiled={compiled} snippets_skipped={snippets} failed={failed}")
    return 1 if failed else 0


if __name__ == "__main__":
    raise SystemExit(main())