#!/usr/bin/env python3
"""Detect uncommitted edits in upstream-owned source trees.

Default mode (no flags): emit a human-readable report and exit 0.
Strict mode (--strict, the default when REDBEAR_BUILD_PHASE is set):
emit the same report and exit non-zero if any tree is dirty. This is
how `build-redbear.sh` ensures that any edits to upstream-owned source
trees under `recipes/core/<component>/source/` (which are symlinks into
`local/sources/<component>/`) are detected and either committed or
explicitly overridden via REDBEAR_ALLOW_DIRTY.

The override is --no-strict, which forces exit 0 even when dirty. This
matches the REDBEAR_ALLOW_DIRTY=1 escape hatch in build-redbear.sh.
"""

import argparse
import os
import subprocess
import sys
from pathlib import Path

PROJECT_ROOT = Path(__file__).resolve().parents[2]
UPSTREAM_OWNED = {
    "kernel": PROJECT_ROOT / "recipes/core/kernel/source",
    "base": PROJECT_ROOT / "recipes/core/base/source",
    "relibc": PROJECT_ROOT / "recipes/core/relibc/source",
    "bootloader": PROJECT_ROOT / "recipes/core/bootloader/source",
    "installer": PROJECT_ROOT / "recipes/core/installer/source",
    "redoxfs": PROJECT_ROOT / "recipes/core/redoxfs/source",
}


def git_has_changes(repo: Path) -> tuple[bool, list[str]]:
    if not (repo / ".git").exists():
        return False, []
    proc = subprocess.run(
        ["git", "status", "--short"],
        cwd=repo,
        check=False,
        capture_output=True,
        text=True,
    )
    lines = [line.rstrip() for line in proc.stdout.splitlines() if line.strip()]
    return bool(lines), lines


def main() -> int:
    parser = argparse.ArgumentParser(
        description="Detect uncommitted edits in upstream-owned Red Bear OS source trees.",
    )
    # Default to strict when invoked from a canonical build (REDBEAR_BUILD_PHASE
    # is set by build-redbear.sh). Default to non-strict for ad-hoc operator use.
    canonical = bool(os.environ.get("REDBEAR_BUILD_PHASE"))
    parser.add_argument(
        "--strict",
        action="store_true",
        default=canonical,
        help="Exit non-zero if any tree is dirty (default when REDBEAR_BUILD_PHASE is set)",
    )
    parser.add_argument(
        "--no-strict",
        dest="strict",
        action="store_false",
        help="Always exit 0, even when dirty (override REDBEAR_BUILD_PHASE default)",
    )
    args = parser.parse_args()

    dirty = False
    for label, repo in UPSTREAM_OWNED.items():
        has_changes, lines = git_has_changes(repo)
        if not has_changes:
            continue
        dirty = True
        print(f"{label}\tDIRTY\t{repo.relative_to(PROJECT_ROOT)}")
        for line in lines[:20]:
            print(f"  {line}")
        if len(lines) > 20:
            print(f"  ... {len(lines) - 20} more")

    if args.strict and dirty:
        print("", file=sys.stderr)
        print("ERROR: uncommitted edits detected in upstream-owned source trees.", file=sys.stderr)
        print("       Use --no-strict to allow, or commit your changes.", file=sys.stderr)
        return 1
    return 0


if __name__ == "__main__":
    sys.exit(main())