"""ORCH-088 — serial gate end-to-end queue behaviour (real tmp SQLite).

Covers (04-test-plan.yaml):
  TC-04  after A.stage='done' the waiting analyst-job of B is claimed (gate opens
         automatically — no manual action).
  TC-05  a queue of 3 tasks of one repo is processed strictly one-at-a-time, FIFO
         by jobs.id: while A is unfinished neither B nor C starts.
  TC-06  restart-safe: the active task is derived from the DB (tasks.repo +
         stage!='done'), not in-memory — re-reading state keeps the gate closed.
"""
import os
import tempfile

import pytest

os.environ["ORCH_DB_PATH"] = os.path.join(tempfile.gettempdir(), "test_serial_gate_e2e.db")
os.environ.setdefault("ORCH_GITEA_TOKEN", "test-token")
os.environ.setdefault("ORCH_PLANE_API_TOKEN", "test-token")

import src.db as db  # noqa: E402
from src.db import init_db, get_db, enqueue_job, claim_next_job  # noqa: E402
from src import config as cfg  # noqa: E402


@pytest.fixture(autouse=True)
def fresh_db(tmp_path, monkeypatch):
    dbfile = tmp_path / "e2e.db"
    monkeypatch.setattr(db.settings, "db_path", str(dbfile))
    monkeypatch.setattr(cfg.settings, "serial_gate_enabled", True, raising=False)
    monkeypatch.setattr(cfg.settings, "serial_gate_repos", "", raising=False)
    monkeypatch.setattr(cfg.settings, "serial_gate_freeze_enabled", True, raising=False)
    monkeypatch.setattr(cfg.settings, "task_deps_enabled", False, raising=False)
    init_db()
    yield


def _make_task(work_item_id, stage="analysis", repo="orchestrator"):
    conn = get_db()
    cur = conn.execute(
        "INSERT INTO tasks (plane_id, work_item_id, repo, branch, stage) "
        "VALUES (?, ?, ?, ?, ?)",
        (work_item_id, work_item_id, repo, f"feature/{work_item_id}", stage),
    )
    tid = cur.lastrowid
    conn.commit()
    conn.close()
    return tid


def _set_stage(task_id, stage):
    conn = get_db()
    conn.execute("UPDATE tasks SET stage=? WHERE id=?", (stage, task_id))
    conn.commit()
    conn.close()


# --------------------------------------------------------------- TC-04
def test_next_starts_automatically_when_predecessor_done():
    a = _make_task("ORCH-301", stage="development")
    b = _make_task("ORCH-302", stage="analysis")
    job_b = enqueue_job("analyst", "orchestrator", "B", task_id=b)

    assert claim_next_job() is None, "B gated while A unfinished"

    # A reaches done -> the gate opens on the NEXT claim tick, no manual action.
    _set_stage(a, "done")
    claimed = claim_next_job()
    assert claimed is not None and claimed["id"] == job_b


# --------------------------------------------------------------- TC-05
def test_three_tasks_processed_one_at_a_time_fifo():
    a = _make_task("ORCH-310", stage="analysis")
    b = _make_task("ORCH-311", stage="analysis")
    c = _make_task("ORCH-312", stage="analysis")
    job_a = enqueue_job("analyst", "orchestrator", "A", task_id=a)
    job_b = enqueue_job("analyst", "orchestrator", "B", task_id=b)
    job_c = enqueue_job("analyst", "orchestrator", "C", task_id=c)

    # Only the FIFO-first task (A, lowest id) is claimable.
    claimed = claim_next_job()
    assert claimed is not None and claimed["id"] == job_a
    assert claim_next_job() is None, "B and C must wait while A is unfinished"

    # A runs through to done; now B (next) is claimable, C still waits.
    db.mark_job(job_a, "done")
    _set_stage(a, "done")
    claimed_b = claim_next_job()
    assert claimed_b is not None and claimed_b["id"] == job_b
    assert claim_next_job() is None, "C must wait while B is unfinished"

    # B done -> C claimable last (strict FIFO order preserved).
    db.mark_job(job_b, "done")
    _set_stage(b, "done")
    claimed_c = claim_next_job()
    assert claimed_c is not None and claimed_c["id"] == job_c


# --------------------------------------------------------------- TC-06
def test_restart_safe_active_task_from_db():
    a = _make_task("ORCH-320", stage="development")
    b = _make_task("ORCH-321", stage="analysis")
    job_b = enqueue_job("analyst", "orchestrator", "B", task_id=b)
    assert claim_next_job() is None

    # Simulate a restart: there is NO in-memory state — the gate recomputes purely
    # from the DB. Re-running init_db (idempotent) + a fresh claim must still gate B.
    init_db()
    assert claim_next_job() is None, "after restart the gate is still closed (DB-derived)"

    _set_stage(a, "done")
    claimed = claim_next_job()
    assert claimed is not None and claimed["id"] == job_b