"""Create a clean, shallow Git checkout ZIP that can fast-forward on launch."""

import argparse
from datetime import datetime
import hashlib
import os
from pathlib import Path
import subprocess
import tempfile
from urllib.parse import urlsplit
import zipfile


EXCLUDED_DIRS = {
    ".git",
    ".venv",
    "venv",
    "env",
    "node_modules",
    "__pycache__",
    "__pypackages__",
    ".angular",
    ".gradle",
    ".pytest_cache",
    ".ruff_cache",
    ".mypy_cache",
    ".cache",
    ".tox",
    ".nox",
    ".hypothesis",
    ".eggs",
    ".idea",
    ".vscode",
    ".vs",
    ".codex",
    ".claude",
    ".gemini",
    ".cursor",
    ".roo",
    ".ipynb_checkpoints",
    "build",
    "dist",
    "out",
    "coverage",
    "htmlcov",
    "artifacts",
    "traces",
    "scratch",
    "outputs",
    "trace_output",
}
EXCLUDED_SUFFIXES = {
    ".pyc",
    ".pyo",
    ".pyd",
    ".so",
    ".dll",
    ".exe",
    ".o",
    ".obj",
    ".a",
    ".lib",
    ".class",
    ".jar",
    ".apk",
    ".aab",
    ".wasm",
    ".map",
    ".tsbuildinfo",
    ".egg",
    ".whl",
    ".zip",
    ".7z",
    ".tar",
    ".gz",
    ".log",
    ".db",
    ".sqlite",
    ".sqlite3",
    ".pem",
    ".key",
    ".keystore",
    ".p12",
    ".pfx",
    ".swp",
    ".swo",
}

GIT_METADATA_FILES = {"HEAD", "config", "index", "shallow", "packed-refs"}
GIT_METADATA_DIRS = {"objects", "refs"}
RUNTIME_PAYLOADS = {"packages/artemis-accessibility-helper/ArtemisAccessibilityHelper.apk"}


def excluded(path: Path) -> bool:
    parts = tuple(part.lower() for part in path.parts)
    name = parts[-1]
    if any(part in EXCLUDED_DIRS or part.endswith(".egg-info") for part in parts):
        return True
    # This tracked directory also contains generated Angular bundles.
    if parts[:3] == ("artemis", "resources", "showcase_ui"):
        return True
    if (name == ".env" or name.startswith(".env.")) and name != ".env.example":
        return True
    if name.startswith((".artemis_", ".jetski_", ".coverage")):
        return True
    if name in {".ds_store", "thumbs.db", ".ipc_port", ".ls_address", ".npmrc", ".pypirc"}:
        return True
    # The tracked helper is needed at runtime on fresh Android installations.
    # Keep this exact payload, while excluding unrelated APKs and build outputs.
    if path.as_posix() in RUNTIME_PAYLOADS:
        return False
    return path.suffix.lower() in EXCLUDED_SUFFIXES or name.endswith((".db-wal", ".db-shm", "~"))


def source_files(root: Path):
    for directory, dirs, files in os.walk(root, followlinks=False):
        current = Path(directory)
        dirs[:] = sorted(
            name
            for name in dirs
            if not (current / name).is_symlink()
            and not excluded((current / name).relative_to(root))
        )
        for name in sorted(files):
            path = current / name
            if not path.is_symlink() and not excluded(path.relative_to(root)):
                yield path


def git(root: Path, *args: str) -> str:
    result = subprocess.run(
        ["git", "-C", str(root), *args],
        capture_output=True,
        text=True,
        encoding="utf-8",
        errors="replace",
        timeout=90,
    )
    if result.returncode:
        raise RuntimeError(f"git {args[0]} failed (exit {result.returncode})")
    return result.stdout.strip()


def git_metadata_files(root: Path):
    metadata = root / ".git"
    for name in sorted(GIT_METADATA_FILES):
        path = metadata / name
        if path.is_file():
            yield path
    for name in sorted(GIT_METADATA_DIRS):
        directory = metadata / name
        if directory.exists():
            yield from source_files_without_filter(directory)
    for name in ("exclude", "sparse-checkout"):
        path = metadata / "info" / name
        if path.is_file():
            yield path


def source_files_without_filter(root: Path):
    for directory, dirs, files in os.walk(root, followlinks=False):
        current = Path(directory)
        dirs[:] = sorted(name for name in dirs if not (current / name).is_symlink())
        for name in sorted(files):
            path = current / name
            if not path.is_symlink():
                yield path


def release_remote(root: Path) -> tuple[str, str]:
    if not (root / ".git").exists():
        raise ValueError("Source packaging requires a Git checkout")
    if git(root, "status", "--porcelain", "--untracked-files=no"):
        raise ValueError("Commit tracked changes before packaging a release")
    branch = git(root, "symbolic-ref", "--quiet", "--short", "HEAD")
    remote = git(root, "config", "--get", f"branch.{branch}.remote")
    merge_ref = git(root, "config", "--get", f"branch.{branch}.merge")
    if remote == "." or merge_ref != f"refs/heads/{branch}":
        raise ValueError("The current branch must track the same branch on a remote")
    url = git(root, "remote", "get-url", remote)
    parsed = urlsplit(url)
    if parsed.scheme != "https" or not parsed.hostname or parsed.username or parsed.password:
        raise ValueError("The release upstream must be a credential-free HTTPS URL")
    if parsed.query or parsed.fragment:
        raise ValueError("The release upstream must not contain a query or fragment")
    return branch, url


def package_source(root: Path, output: Path) -> tuple[int, str]:
    root = root.resolve()
    output = output.resolve()
    branch, remote_url = release_remote(root)
    revision = git(root, "rev-parse", "HEAD")
    output.parent.mkdir(parents=True, exist_ok=True)
    temporary = output.with_suffix(".zip.tmp")
    try:
        with tempfile.TemporaryDirectory(prefix="artemis-release-") as work:
            checkout = Path(work) / "artemis"
            git(
                root,
                "clone",
                "--depth",
                "1",
                "--single-branch",
                "--branch",
                branch,
                root.as_uri(),
                str(checkout),
            )
            git(checkout, "remote", "set-url", "origin", remote_url)
            # Generated assets are tracked upstream but must not appear in the
            # unpacked source. Sparse checkout keeps the Git index clean.
            omitted = [
                name for name in git(checkout, "ls-files").splitlines() if excluded(Path(name))
            ]
            patterns = ["/*", *(f"!/{name}" for name in omitted)]
            git(checkout, "sparse-checkout", "set", "--no-cone", *patterns)
            # Rebuilt assets in sparse paths must not look like user edits.
            info_exclude = checkout / ".git" / "info" / "exclude"
            with info_exclude.open("a", encoding="utf-8") as stream:
                stream.write("\n".join(["", *(f"/{name}" for name in omitted), ""]))
            if git(checkout, "rev-parse", "HEAD") != revision or git(
                checkout, "status", "--porcelain"
            ):
                raise RuntimeError("The packaged checkout is not clean at the requested revision")
            files = [*source_files(checkout), *git_metadata_files(checkout)]
            names = {
                str(Path("artemis") / path.relative_to(checkout)).replace("\\", "/")
                for path in files
            }
            with zipfile.ZipFile(temporary, "w", zipfile.ZIP_DEFLATED, compresslevel=6) as archive:
                for path in files:
                    archive.write(path, Path("artemis") / path.relative_to(checkout))
            with zipfile.ZipFile(temporary) as archive:
                bad_file = archive.testzip()
                if bad_file or set(archive.namelist()) != names:
                    raise RuntimeError(
                        f"ZIP integrity check failed: {bad_file or 'file list mismatch'}"
                    )
        temporary.replace(output)
    finally:
        temporary.unlink(missing_ok=True)
    with output.open("rb") as stream:
        digest = hashlib.file_digest(stream, "sha256").hexdigest()
    return len(files), digest


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--root", type=Path, default=Path(__file__).resolve().parents[1])
    parser.add_argument("--output", type=Path)
    args = parser.parse_args()
    output = (
        args.output
        or args.root / "artifacts" / f"artemis-source-{datetime.now():%Y%m%d-%H%M%S}.zip"
    )
    count, digest = package_source(args.root, output)
    print(f"Archive: {output.resolve()}")
    print(f"Files: {count}; size: {output.stat().st_size / (1024 * 1024):.2f} MiB")
    print(f"SHA256: {digest}")