# steward/core/migration_runner.py
from __future__ import annotations
import logging
from pathlib import Path

logger = logging.getLogger(__name__)


def discover_all_plugin_migration_dirs(plugin_dir: Path) -> list[Path]:
    """Scan plugin_dir for any migrations/ subdirs, regardless of enabled status.

    Used by run_core_migrations so Alembic can resolve the full revision graph
    even when a plugin migration is already stamped in alembic_version.
    """
    dirs: list[Path] = []
    if not plugin_dir.exists():
        return dirs
    for entry in sorted(plugin_dir.iterdir()):
        if not entry.is_dir():
            continue
        mdir = entry / "migrations"
        if mdir.exists():
            dirs.append(mdir)
    return dirs


def run_core_migrations(db_url: str, plugin_dir: Path | None = None) -> None:
    """Run core Alembic migrations.

    Includes all discovered plugin migration dirs (if plugin_dir given) so
    Alembic can resolve any previously-applied plugin revisions in the graph.
    Called first so the app_settings table exists before loading settings.
    """
    dirs = discover_all_plugin_migration_dirs(plugin_dir) if plugin_dir else []
    _run(db_url, plugin_migration_dirs=dirs)


def run_plugin_migrations(db_url: str, plugin_migration_dirs: list[Path]) -> None:
    """Run plugin Alembic migrations after settings are loaded."""
    if plugin_migration_dirs:
        _run(db_url, plugin_migration_dirs=plugin_migration_dirs)


def run_migrations(db_url: str, plugin_migration_dirs: list[Path] | None = None) -> None:
    """Run core + plugin Alembic migrations (single-phase convenience wrapper)."""
    _run(db_url, plugin_migration_dirs=plugin_migration_dirs or [])


def _run(db_url: str, plugin_migration_dirs: list[Path]) -> None:
    from alembic import command
    from alembic.config import Config

    core_migrations = Path(__file__).parent.parent / "migrations"
    core_versions = core_migrations / "versions"

    cfg = Config()
    cfg.set_main_option("script_location", str(core_migrations))
    cfg.set_main_option("sqlalchemy.url", db_url)

    version_locs = [str(core_versions)]
    for plugin_dir in plugin_migration_dirs:
        pv = plugin_dir / "versions"
        if pv.exists():
            version_locs.append(str(pv))

    cfg.set_main_option("version_locations", " ".join(version_locs))

    logger.info("Running migrations (version_locations: %s)", " ".join(version_locs))
    command.upgrade(cfg, "heads")
    logger.info("Migrations complete")


def get_plugin_migration_dirs(plugin_dir: Path, plugins_cfg: dict) -> list[Path]:
    """Return migration directories for enabled plugins (filesystem scan only)."""
    dirs = []
    for name, cfg in plugins_cfg.items():
        if not cfg.get("enabled", False):
            continue
        mdir = plugin_dir / name / "migrations"
        if mdir.exists():
            dirs.append(mdir)
    return dirs