"""Build a minimal, offline, hand-rolled Composer package and its
`packages.json` index, for integration-testing the `php` module of
id-configurator.

No network access and no build backend (composer) is used: the package is a
plain zip file assembled with the standard library only, so this script can
run in a minimal Python image with nothing installed.
"""

from __future__ import annotations

import hashlib
import io
import json
import pathlib
import zipfile

VENDOR = "interdiode"
PACKAGE = "idconfiguratortestpkg"
NAME = f"{VENDOR}/{PACKAGE}"
VERSION = "0.0.1"
ZIP_NAME = f"{PACKAGE}-{VERSION}.zip"
OUT_DIR = pathlib.Path("/srv")

COMPOSER_JSON = json.dumps({"name": NAME, "version": VERSION, "type": "library"})


def build_zip() -> bytes:
    buffer = io.BytesIO()
    with zipfile.ZipFile(buffer, "w", zipfile.ZIP_DEFLATED) as archive:
        archive.writestr("composer.json", COMPOSER_JSON)
        archive.writestr(
            "marker.txt",
            "test-only package served by the id-configurator integration tests\n",
        )
    return buffer.getvalue()


def write_packages_json(out_dir: pathlib.Path, zip_content: bytes) -> None:
    # Composer requires a fully-qualified dist URL: unlike PyPI's simple
    # index, it does not resolve relative/root-relative ones against the
    # repository's own URL for this (non-v2) repository format. The host
    # and port this fixture will actually be reached on aren't known at
    # image-build time (tox-docker only assigns them once the container
    # starts), so this bakes in a placeholder that nginx's sub_filter
    # rewrites to the real https://<host used by the client>/ at request
    # time (see php-repo.nginx.conf).
    packages = {
        "packages": {
            NAME: {
                VERSION: {
                    "name": NAME,
                    "version": VERSION,
                    "dist": {
                        "type": "zip",
                        "url": f"__BASE_URL__/{ZIP_NAME}",
                        "shasum": hashlib.sha1(zip_content).hexdigest(),  # nosec B324
                    },
                }
            }
        }
    }
    (out_dir / "packages.json").write_text(
        json.dumps(packages, indent=2), encoding="utf-8"
    )


def main() -> None:
    OUT_DIR.mkdir(parents=True, exist_ok=True)
    zip_content = build_zip()
    (OUT_DIR / ZIP_NAME).write_bytes(zip_content)
    write_packages_json(OUT_DIR, zip_content)


if __name__ == "__main__":
    main()