#!/usr/bin/env python3
"""
sync_helpers.py - small helper used by sync.sh

Two jobs, on purpose kept out of bash because reliable YAML parsing and XML
escaping in pure bash/sed is a losing game:

  parse-yaml <file>
      Reads the "sources:" list from the YAML file and prints it as JSON
      on stdout, so sync.sh can loop over it safely (no word-splitting
      issues, handles quoting etc.).

  gen-appstream <origin> <entries_json>
      entries_json is a JSON array of {"name":..., "summary":...} objects
      (only the *explicitly requested* top-level packages, never pulled-in
      dependencies). Prints a minimal AppStream "generic component" catalog
      on stdout, which sync.sh gzips and injects into the repo metadata via
      modifyrepo_c.

      NOTE: "generic" components (no icon/screenshots/.desktop file) make a
      package installable from GNOME Software / Discover and show up in
      search, but will NOT appear on the curated "Explore" front page -
      that's a GNOME Software behaviour for non-desktop-app components, not
      something fixable at the repo-metadata level.
"""
import sys
import json
import argparse
from xml.sax.saxutils import escape


def cmd_parse_yaml(path: str) -> None:
    try:
        import yaml
    except ImportError:
        sys.stderr.write(
            "ERROR: python3-pyyaml (PyYAML) is not installed.\n"
            "Install it with: dnf install -y python3-pyyaml\n"
        )
        sys.exit(1)

    with open(path, "r", encoding="utf-8") as fh:
        data = yaml.safe_load(fh) or {}

    sources = data.get("sources") or []
    if not isinstance(sources, list):
        sys.stderr.write("ERROR: 'sources' in YAML is not a list\n")
        sys.exit(1)

    for i, src in enumerate(sources):
        for field in ("name", "baseurl", "packages"):
            if field not in src:
                sys.stderr.write(
                    f"ERROR: source #{i} is missing required field '{field}'\n"
                )
                sys.exit(1)
        if not isinstance(src["packages"], list) or not src["packages"]:
            sys.stderr.write(
                f"ERROR: source '{src.get('name')}' has an empty/invalid packages list\n"
            )
            sys.exit(1)

    json.dump(sources, sys.stdout)


def cmd_gen_appstream(origin: str, entries_json: str) -> None:
    entries = json.loads(entries_json)
    print('<?xml version="1.0" encoding="UTF-8"?>')
    print(f'<components version="0.14" origin="{escape(origin)}">')
    for e in entries:
        name = e.get("name", "")
        summary = e.get("summary") or f"{name} (mirrored package)"
        cid = f"{name}.generic"
        print('  <component type="generic">')
        print(f"    <id>{escape(cid)}</id>")
        print(f"    <pkgname>{escape(name)}</pkgname>")
        print(f"    <name>{escape(name)}</name>")
        print(f"    <summary>{escape(summary)}</summary>")
        print("    <metadata_license>CC0-1.0</metadata_license>")
        print("    <project_license>unknown</project_license>")
        print("  </component>")
    print("</components>")


def main() -> None:
    ap = argparse.ArgumentParser()
    sub = ap.add_subparsers(dest="cmd", required=True)

    p1 = sub.add_parser("parse-yaml")
    p1.add_argument("path")

    p2 = sub.add_parser("gen-appstream")
    p2.add_argument("origin")
    p2.add_argument("entries_json")

    args = ap.parse_args()

    if args.cmd == "parse-yaml":
        cmd_parse_yaml(args.path)
    elif args.cmd == "gen-appstream":
        cmd_gen_appstream(args.origin, args.entries_json)


if __name__ == "__main__":
    main()