import datetime as dt
import os
from types import SimpleNamespace

import pytest
from fastapi.testclient import TestClient


def is_roughly_now(datetime_str):
    """Check if a datetime string is roughly from now"""
    now = dt.datetime.utcnow()
    datetime = dt.datetime.fromisoformat(datetime_str)
    return (now - datetime).total_seconds() < 3


class TestWebservice:
    @pytest.fixture(autouse=True)
    def db_file(self, tmp_path):
        filename = tmp_path / "test-db.sqlite"
        os.environ["DB_FILE_NAME"] = str(filename)

    @pytest.fixture
    def client(self):
        from gistillery.webservice import app

        client = TestClient(app)
        client.get("/clear")
        return client

    @pytest.fixture
    def mlregistry(self):
        # use dummy models
        from gistillery.ml import MlRegistry, RawTextProcessor, Summarizer, Tagger

        class DummySummarizer(Summarizer):
            """Returns the first 10 characters of the input"""
            def __init__(self, *args, **kwargs):
                pass

            def get_name(self):
                return "dummy summarizer"

            def __call__(self, x):
                return x[:10]

        class DummyTagger(Tagger):
            """Returns the first 3 words of the input"""
            def __init__(self, *args, **kwargs):
                pass

            def get_name(self):
                return "dummy tagger"

            def __call__(self, x):
                return ["#" + word for word in x.split(maxsplit=4)[:3]]

        registry = MlRegistry()
        registry.register_processor(RawTextProcessor())

        # arguments don't matter for dummy summarizer and tagger
        summarizer = DummySummarizer(None, None, None, None)
        registry.register_summarizer(summarizer)

        tagger = DummyTagger(None, None, None, None)
        registry.register_tagger(tagger)
        return registry

    def process_jobs(self, registry):
        # emulate work of the background worker
        from gistillery.worker import check_pending_jobs, process_job

        jobs = check_pending_jobs()
        for job in jobs:
            process_job(job, registry)

    def test_status(self, client):
        resp = client.get("/status")
        assert resp.status_code == 200
        assert resp.json() == "OK"

    def test_recent_empty(self, client):
        resp = client.get("/recent")
        assert resp.json() == []

    def test_recent_tag_empty(self, client):
        resp = client.get("/recent/general")
        assert resp.json() == []

    def test_submitted_job_status_pending(self, client, monkeypatch):
        # monkeypatch uuid4 to return a known value
        job_id = "abc1234"
        monkeypatch.setattr("uuid.uuid4", lambda: SimpleNamespace(hex=job_id))
        client.post("/submit", json={"author": "ben", "content": "this is a test"})

        resp = client.get(f"/check_job_status/{job_id}")
        output = resp.json()
        last_updated = output.pop("last_updated")
        assert output == {
            "id": job_id,
            "status": "pending",
        }
        assert is_roughly_now(last_updated)

    def test_submitted_job_status_not_found(self, client, monkeypatch):
        # monkeypatch uuid4 to return a known value
        job_id = "abc1234"
        monkeypatch.setattr("uuid.uuid4", lambda: SimpleNamespace(hex=job_id))
        client.post("/submit", json={"author": "ben", "content": "this is a test"})

        other_job_id = "def5678"
        resp = client.get(f"/check_job_status/{other_job_id}")
        output = resp.json()
        last_updated = output.pop("last_updated")
        assert output == {
            "id": other_job_id,
            "status": "not found",
        }
        assert last_updated is None

    def test_submitted_job_status_done(self, client, mlregistry, monkeypatch):
        # monkeypatch uuid4 to return a known value
        job_id = "abc1234"
        monkeypatch.setattr("uuid.uuid4", lambda: SimpleNamespace(hex=job_id))
        client.post("/submit", json={"author": "ben", "content": "this is a test"})
        self.process_jobs(mlregistry)

        resp = client.get(f"/check_job_status/{job_id}")
        output = resp.json()
        last_updated = output.pop("last_updated")
        assert output == {
            "id": job_id,
            "status": "done",
        }
        assert is_roughly_now(last_updated)

    def test_recent_with_entries(self, client, mlregistry):
        # submit 2 entries
        client.post(
            "/submit", json={"author": "maxi", "content": "this is a first test"}
        )
        client.post(
            "/submit", json={"author": "mini", "content": "this would be something else"}
        )
        self.process_jobs(mlregistry)
        resp = client.get("/recent").json()

        # results are sorted by recency but since dummy models are so fast, the
        # date in the db could be the same, so we sort by author
        resp = sorted(resp, key=lambda x: x["author"])
        assert len(resp) == 2

        resp0 = resp[0]
        assert resp0["author"] == "maxi"
        assert resp0["summary"] == "this is a "
        assert resp0["tags"] == sorted(["#this", "#is", "#a"])

        resp1 = resp[1]
        assert resp1["author"] == "mini"
        assert resp1["summary"] == "this would"
        assert resp1["tags"] == sorted(["#this", "#would", "#be"])

    def test_recent_tag_with_entries(self, client, mlregistry):
        # submit 2 entries
        client.post(
            "/submit", json={"author": "maxi", "content": "this is a first test"}
        )
        client.post(
            "/submit", json={"author": "mini", "content": "this would be something else"}
        )
        self.process_jobs(mlregistry)

        # the "this" tag is in both entries
        resp = client.get("/recent/this").json()
        assert len(resp) == 2

        # the "would" tag is in only one entry
        resp = client.get("/recent/would").json()
        assert len(resp) == 1

        resp0 = resp[0]
        assert resp0["author"] == "mini"
        assert resp0["summary"] == "this would"
        assert resp0["tags"] == sorted(["#this", "#would", "#be"])

    def test_submitted_job_failed(self, client, mlregistry, monkeypatch):
        # monkeypatch uuid4 to return a known value
        job_id = "abc1234"
        monkeypatch.setattr("uuid.uuid4", lambda: SimpleNamespace(hex=job_id))
        client.post("/submit", json={"author": "ben", "content": "this is a test"})
        # patch gistillery.worker._process_job to raise an exception

        def raise_(ex):
            raise ex

        monkeypatch.setattr(
            "gistillery.worker._process_job",
            lambda job, registry: raise_(RuntimeError("something went wrong")),
        )
        self.process_jobs(mlregistry)

        resp = client.get(f"/check_job_status/{job_id}")
        output = resp.json()
        output.pop("last_updated")
        assert output == {
            "id": job_id,
            "status": "failed",
        }