"""Tests for the job queue, cancellation, cache and confidence tiers (no model inference)."""

from __future__ import annotations

import asyncio

import pytest

from app.services import analysis_jobs as aj
from app.services.analysis_jobs import (
    FILE_STEPS, STEP_DONE, STEP_RUNNING, CpuGate, JobCancelled, JobStore, Progress, ResultCache,
)
from app.services.inference_xai import XAIInferenceService

OK = {"result": {"ok": True}, "warnings": [], "errors": []}


@pytest.fixture(autouse=True)
def fresh_state(monkeypatch):
    """Each test gets its own gate and cache."""
    monkeypatch.setattr(aj, "cpu_gate", CpuGate(1))
    monkeypatch.setattr(aj, "result_cache", ResultCache(8, 3600))


def gated(hold: float = 0.05):
    """A job that takes the CPU slot like the real pipeline does."""
    async def work(job):
        async with aj.cpu_gate.slot(job.id, job.progress):
            job.progress.running("features")
            await asyncio.sleep(hold)
            job.progress.set("features", STEP_DONE)
        return OK
    return work


def test_jobs_take_the_cpu_one_at_a_time_in_order() -> None:
    async def scenario() -> None:
        store = JobStore()
        jobs = [store.start("file", FILE_STEPS, gated(0.05)) for _ in range(3)]
        await asyncio.sleep(0.01)
        snaps = [j.to_dict() for j in jobs]
        assert snaps[0]["phase"] == "running" and "queue" not in snaps[0]
        assert snaps[1]["status"] == "running" and snaps[1]["phase"] == "queued"
        assert snaps[1]["queue"]["position"] == 1 and snaps[1]["queue"]["ahead"] == 1
        assert snaps[2]["queue"]["position"] == 2
        await asyncio.sleep(0.25)
        assert all(j.to_dict()["status"] == "done" for j in jobs)
        # The gate now knows how long a job holds the CPU... only past 1 s, so still None here.
        assert aj.cpu_gate.estimated_wait(1) is None

    asyncio.run(scenario())


def test_cancelling_a_queued_job_frees_its_place() -> None:
    async def scenario() -> None:
        store = JobStore()
        first = store.start("file", FILE_STEPS, gated(0.1))
        second = store.start("file", FILE_STEPS, gated(0.1))
        third = store.start("file", FILE_STEPS, gated(0.1))
        await asyncio.sleep(0.01)
        store.cancel(second.id)
        await asyncio.sleep(0.01)
        assert second.status == "error" and second.response["errors"] == ["cancelled"]
        assert third.to_dict()["queue"]["position"] == 1
        await asyncio.sleep(0.3)
        assert first.status == "done" and third.status == "done"

    asyncio.run(scenario())


def test_cancelling_a_running_job_stops_it_at_the_next_check() -> None:
    async def scenario() -> None:
        store = JobStore()

        async def work(job):
            async with aj.cpu_gate.slot(job.id, job.progress):
                await asyncio.sleep(0.05)
            job.progress.check()
            return OK

        job = store.start("file", FILE_STEPS, work)
        await asyncio.sleep(0.01)
        store.cancel(job.id)
        await asyncio.sleep(0.1)
        assert job.status == "error" and job.response["errors"] == ["cancelled"]

    asyncio.run(scenario())


def test_a_job_nobody_polls_is_dropped_when_its_turn_comes(monkeypatch) -> None:
    monkeypatch.setattr(aj, "ABANDON_SEC", 0.02)

    async def scenario() -> None:
        store = JobStore()
        store.start("file", FILE_STEPS, gated(0.08))
        waiting = store.start("file", FILE_STEPS, gated(0.01))
        await asyncio.sleep(0.2)
        assert waiting.status == "error" and waiting.response["errors"] == ["job_abandoned"]

    asyncio.run(scenario())


def test_same_file_shares_the_running_job_then_hits_the_cache() -> None:
    async def scenario() -> None:
        store = JobStore()
        a = store.start("file", FILE_STEPS, gated(0.05), key="file:abc")
        b = store.start("file", FILE_STEPS, gated(0.05), key="file:abc")
        assert a is b
        await asyncio.sleep(0.15)
        c = store.start("file", FILE_STEPS, gated(0.05), key="file:abc")
        assert c is not a and c.cached and c.status == "done" and c.response == OK

    asyncio.run(scenario())


def test_full_queue_is_refused(monkeypatch) -> None:
    monkeypatch.setattr(aj, "MAX_PENDING", 2)

    async def scenario() -> None:
        store = JobStore()
        store.start("file", FILE_STEPS, gated(0.05))
        store.start("file", FILE_STEPS, gated(0.05))
        with pytest.raises(aj.QueueFull):
            store.start("file", FILE_STEPS, gated(0.05))
        await asyncio.sleep(0.2)

    asyncio.run(scenario())


def test_failed_job_settles_as_error() -> None:
    async def scenario() -> None:
        store = JobStore()

        async def boom(job):
            raise RuntimeError("boom")

        job = store.start("file", FILE_STEPS, boom)
        await asyncio.sleep(0.01)
        assert job.status == "error"
        assert job.response == {"result": None, "warnings": [], "errors": ["internal_error"]}

    asyncio.run(scenario())


def test_progress_check_raises_when_cancelled() -> None:
    progress = Progress(FILE_STEPS)
    progress.check()
    progress.cancelled = True
    with pytest.raises(JobCancelled):
        progress.check()


def test_confidence_band_is_measured_from_the_threshold() -> None:
    svc = XAIInferenceService.__new__(XAIInferenceService)
    svc.threshold = 0.431577
    assert svc._confidence_band(0.45).tier == "uncertain"
    assert svc._confidence_band(0.40).tier == "uncertain"
    assert svc._confidence_band(0.97).tier == "very_strong"
    assert svc._confidence_band(0.02).tier == "very_strong"
    assert svc._confidence_band(0.431577).margin == 0.0


def test_progress_reports_how_far_a_running_step_is() -> None:
    progress = Progress(FILE_STEPS)
    progress.set("timeline", STEP_RUNNING)
    progress.advance("timeline", 3, 12)
    item = next(s for s in progress.snapshot() if s["id"] == "timeline")
    assert item["progress"] == 0.25

    progress.set("timeline", STEP_DONE)
    item = next(s for s in progress.snapshot() if s["id"] == "timeline")
    assert "progress" not in item