from __future__ import annotations

import importlib
import importlib.resources
import shutil
from pathlib import Path

import click


@click.group()
def iti_system_cli() -> None:
    """iTi-System commands."""


@iti_system_cli.group()
def seed() -> None:
    """Seed system-domain data."""


@seed.command("system")
@click.argument("app_import")
def seed_system(app_import: str) -> None:
    app = _load_app(app_import)
    registry = getattr(app.state, "iti_modules", None)
    factory = getattr(app.state, "db_sessionmaker", None)
    if factory is None:
        raise click.ClickException("app database is not configured")

    from .seeds.system import seed_system_data

    with factory() as db:
        summary = seed_system_data(db, registry)
    for name, result in summary.items():
        click.echo(
            f"{name}: created {result['created']}, updated {result['updated']}, skipped {result['skipped']}"
        )


@iti_system_cli.group()
def migrations() -> None:
    """System migration helpers."""


@migrations.command("sync")
@click.option(
    "--target",
    default="migrations/versions",
    show_default=True,
    help="业务项目 migration versions 目录",
)
def sync_migrations(target: str) -> None:
    target_dir = Path(target)
    target_dir.mkdir(parents=True, exist_ok=True)

    synced: list[str] = []
    skipped: list[str] = []
    source_root = importlib.resources.files("iti_system.migrations").joinpath("versions")
    for source in source_root.iterdir():
        if not source.name.endswith(".py") or source.name == "__init__.py":
            continue
        target_file = target_dir / source.name
        if target_file.exists():
            skipped.append(source.name)
            continue
        with importlib.resources.as_file(source) as source_path:
            shutil.copy2(source_path, target_file)
        synced.append(source.name)

    for name in synced:
        click.echo(f"synced: {name}")
    for name in skipped:
        click.echo(f"skipped: {name}")
    click.echo(f"summary: synced {len(synced)}, skipped {len(skipped)}")


def _load_app(app_import: str):
    module_name, _, attr_name = app_import.partition(":")
    if not module_name or not attr_name:
        raise click.ClickException("app import must use module:attribute")
    module = importlib.import_module(module_name)
    app = getattr(module, attr_name)
    return app() if callable(app) else app