#!/usr/bin/env python3

import hashlib
import json
import shutil
import subprocess
from pathlib import Path
import sys


ROOT = Path(__file__).resolve().parent
MANIFEST = ROOT / "offline" / "manifest.json"
BASE_IMAGE = "redroid/redroid:13.0.0-latest"


def digest(path, algorithm):
    hasher = hashlib.new(algorithm)
    with path.open("rb") as handle:
        for chunk in iter(lambda: handle.read(1024 * 1024), b""):
            hasher.update(chunk)
    return hasher.hexdigest()


def runtime_available(runtime):
    return shutil.which(runtime) is not None


def local_base_image_present():
    for runtime in ("docker", "podman"):
        if not runtime_available(runtime):
            continue
        result = subprocess.run(
            [runtime, "image", "inspect", BASE_IMAGE],
            stdout=subprocess.DEVNULL,
            stderr=subprocess.DEVNULL,
            check=False,
        )
        if result.returncode == 0:
            return True, runtime
    return False, ""


def main():
    manifest = json.loads(MANIFEST.read_text(encoding="utf-8"))
    failures = []
    base_image_present, base_runtime = local_base_image_present()
    for entry in manifest["artifacts"]:
        path = ROOT / entry["relative_path"]
        if path.name == "redroid-redroid-13.0.0-latest.tar" and base_image_present:
            print("SKIP {} ({} already present locally)".format(entry["relative_path"], BASE_IMAGE))
            continue
        if not path.is_file():
            if path.name == "redroid-redroid-13.0.0-latest.tar":
                failures.append(
                    "{} missing (and {} not found in local {} storage)".format(
                        entry["relative_path"], BASE_IMAGE, base_runtime or "docker/podman"
                    )
                )
                continue
            failures.append("{} missing".format(entry["relative_path"]))
            continue
        if path.stat().st_size != entry["size"]:
            failures.append("{} size mismatch".format(entry["relative_path"]))
            continue
        sha256 = digest(path, "sha256")
        if sha256 != entry["sha256"]:
            failures.append("{} sha256 mismatch".format(entry["relative_path"]))
            continue
        print("OK  {}".format(entry["relative_path"]))

    if failures:
        for item in failures:
            print("FAIL {}".format(item))
        sys.exit(1)

    print("Offline bundle is complete.")


if __name__ == "__main__":
    main()