from __future__ import annotations

from pathlib import Path

from app.core.config import settings
from app.repositories.scheme_artifacts import (
    delete_scheme_artifacts_by_artifact_ids,
    list_artifacts_by_type,
)

PUBLISH_PREVIEW_ARTIFACT_TYPE = "publish_preview"


def _preview_root() -> Path:
    path = Path(settings.storage_preview_dir)
    path.mkdir(parents=True, exist_ok=True)
    return path


def _cleanup_file_and_empty_parent(path: Path) -> bool:
    removed = False

    try:
        if path.exists() and path.is_file():
            path.unlink()
            removed = True
    except FileNotFoundError:
        pass

    try:
        parent = path.parent
        root = _preview_root()
        if parent != root and parent.exists():
            parent.rmdir()
    except OSError:
        pass

    return removed


async def inspect_publish_preview_storage() -> dict:
    rows = await list_artifacts_by_type(artifact_type=PUBLISH_PREVIEW_ARTIFACT_TYPE)
    root = _preview_root()

    db_by_path: dict[str, object] = {row.storage_path: row for row in rows}
    disk_files = sorted(str(path) for path in root.glob("*/*.json"))

    orphan_files = [path for path in disk_files if path not in db_by_path]
    missing_files_for_db_rows = [
        {
            "artifact_id": row.artifact_id,
            "scheme_id": row.scheme_id,
            "scheme_version_id": row.scheme_version_id,
            "artifact_variant": row.artifact_variant,
            "storage_path": row.storage_path,
        }
        for row in rows
        if not Path(row.storage_path).exists()
    ]

    return {
        "artifact_type": PUBLISH_PREVIEW_ARTIFACT_TYPE,
        "db_rows_count": len(rows),
        "disk_files_count": len(disk_files),
        "orphan_files_count": len(orphan_files),
        "missing_files_for_db_rows_count": len(missing_files_for_db_rows),
        "orphan_files": orphan_files,
        "missing_files_for_db_rows": missing_files_for_db_rows,
    }


async def cleanup_publish_preview_storage(*, dry_run: bool = True) -> dict:
    audit = await inspect_publish_preview_storage()

    orphan_files = [Path(path) for path in audit["orphan_files"]]
    missing_rows = audit["missing_files_for_db_rows"]

    deleted_files: list[str] = []
    deleted_db_artifact_ids: list[str] = []

    if not dry_run:
        for path in orphan_files:
            if _cleanup_file_and_empty_parent(path):
                deleted_files.append(str(path))

        deleted_db_artifact_ids = [
            item["artifact_id"] for item in missing_rows
        ]
        await delete_scheme_artifacts_by_artifact_ids(deleted_db_artifact_ids)

    return {
        "artifact_type": PUBLISH_PREVIEW_ARTIFACT_TYPE,
        "dry_run": dry_run,
        "orphan_files_count": len(orphan_files),
        "missing_files_for_db_rows_count": len(missing_rows),
        "orphan_files": [str(path) for path in orphan_files],
        "missing_files_for_db_rows": missing_rows,
        "deleted_files_count": len(deleted_files),
        "deleted_files": deleted_files,
        "deleted_db_rows_count": len(deleted_db_artifact_ids),
        "deleted_db_artifact_ids": deleted_db_artifact_ids,
    }