"""CLI parsing + entry point dispatch.

Flag style mirrors packwiz-installer-bootstrap so operators wiring Prism's
PreLaunch/PostExit hooks don't relearn the surface. Supports both
``--url value`` and ``--url=value`` forms.
"""

from __future__ import annotations

import argparse
import sys
from dataclasses import dataclass
from pathlib import Path


@dataclass(frozen=True)
class Args:
    """Parsed CLI args shared by both pull + push subcommands."""

    url: str
    pack_folder: Path
    token_file: Path
    restic_binary: Path | None  # None → auto-discover
    allow_download: bool
    headless: bool


def build_parser() -> argparse.ArgumentParser:
    p = argparse.ArgumentParser(
        prog="cloud-sync",
        description="Per-user Minecraft state sync via restic.",
    )
    p.add_argument("--version", action="version", version="cloud-sync 0.1.0")

    sub = p.add_subparsers(dest="cmd", required=True)
    for name in ("pull", "push"):
        sp = sub.add_parser(name, help=f"{name} player state")
        sp.add_argument(
            "--url", required=True,
            help="cloud-svc data plane URL (e.g. https://cloud.tm.center)",
        )
        sp.add_argument(
            "--pack-folder", default=".", type=Path,
            help="Minecraft instance directory (default: cwd)",
        )
        sp.add_argument(
            "--token-file", default=None, type=Path,
            help="Token file path (default: <pack-folder>/.cloud-sync/token)",
        )
        sp.add_argument(
            "--restic-binary", default=None, type=Path,
            help="Path to a restic binary; overrides auto-discovery",
        )
        sp.add_argument(
            "--no-download", action="store_true",
            help="Don't auto-fetch restic from upstream; fail if not found locally",
        )
        sp.add_argument(
            "-g", "--no-gui", action="store_true",
            help="Headless mode (no Swing/Qt windows, restic stdout only)",
        )
    return p


def parse(argv: list[str]) -> tuple[str, Args]:
    """Parse argv → (subcommand, Args). Raises SystemExit on error/help."""
    ns = build_parser().parse_args(argv)
    pack = Path(ns.pack_folder).absolute().resolve()
    token = (
        Path(ns.token_file).absolute()
        if ns.token_file is not None
        else pack / ".cloud-sync" / "token"
    )
    return ns.cmd, Args(
        url=ns.url,
        pack_folder=pack,
        token_file=token,
        restic_binary=Path(ns.restic_binary).absolute() if ns.restic_binary else None,
        allow_download=not ns.no_download,
        headless=ns.no_gui,
    )


def main(argv: list[str] | None = None) -> int:
    """CLI entrypoint. Returns exit code (0=ok, 1=user cancel, 2=error)."""
    # Imports kept here so tests of parse() don't drag UI in.
    from . import sync, ui

    try:
        cmd, args = parse(sys.argv[1:] if argv is None else argv)
    except SystemExit as e:
        return int(e.code) if isinstance(e.code, int) else 2

    action = {"pull": sync.pull, "push": sync.push}[cmd]
    progress = ui.make_progress(headless=args.headless)
    title = "Cloud sync — pulling" if cmd == "pull" else "Cloud sync — pushing"

    try:
        return progress.run_with(lambda: action(args, progress), title)
    except KeyboardInterrupt:
        print("cloud-sync: cancelled", file=sys.stderr)
        return 1
    except Exception as e:  # noqa: BLE001
        print(f"cloud-sync {cmd}: {e}", file=sys.stderr)
        return 2