"""
Light-weight *runs* endpoint to query artefacts produced by workers.

    • `GET /runs/{run_id}`     → metadata & locations for a finished / running flow
"""

from __future__ import annotations

from pathlib import Path
from typing import Any

from fastapi import APIRouter, HTTPException
from librarian_core.storage.worker_store import WorkerStore
from pydantic import BaseModel

router = APIRouter(tags=["runs"])


# --------------------------------------------------------------------------- #
# response model                                                              #
# --------------------------------------------------------------------------- #
class RunInfo(BaseModel):
    run_id: str
    worker: str
    state: str
    dir: Path
    data: dict | None = None


# --------------------------------------------------------------------------- #
# helper                                                                      #
# --------------------------------------------------------------------------- #
def _open_store(run_id: str) -> WorkerStore:
    try:
        return WorkerStore.open(run_id)
    except FileNotFoundError as exc:
        raise HTTPException(status_code=404, detail="Run-id not found") from exc


# --------------------------------------------------------------------------- #
# routes                                                                      #
# --------------------------------------------------------------------------- #
@router.get("/{run_id}", response_model=RunInfo)
def get_run(run_id: str) -> RunInfo:
    """
    Return coarse-grained information about a single flow run.

    For the web-UI we expose only minimal metadata plus the local directory
    where files were written; clients can read further details from disk.
    """
    store = _open_store(run_id)
    meta = store.metadata  # {'worker_name': …, 'state': …, …}

    return RunInfo(
        run_id=run_id,
        worker=meta["worker_name"],
        state=meta["state"],
        dir=store.data_dir,
        data=store.load_model(as_dict=True), # type: ignore
    )

@router.get("/{worker_name}/latest", response_model=RunInfo | None)
def get_latest_run(worker_name: str) -> RunInfo | None:
    artifact: dict[str, Any] | None = WorkerStore.load_latest(worker_name=worker_name)
    if artifact is None:
        raise HTTPException(status_code=404, detail="No runs found")

    store = _open_store(artifact["run_id"])
    meta = store.metadata
    return RunInfo(
        run_id=artifact["run_id"],
        worker=worker_name,
        state=meta["state"],
        dir=artifact["dir"],
        data=artifact["data"],
    )


@router.get("/{run_id}/artifact")
def get_artifact(run_id: str) -> str:
    store = _open_store(run_id)
    # Check if the artifact.md file exists
    if not store._run_dir.joinpath("artifact.md").exists():
        raise HTTPException(status_code=404, detail="Artifact not found")
    return store._run_dir.joinpath("artifact.md").read_text()