from __future__ import annotations

import pytest

from api_layer.server import create_server
from brain.decision_maker import DecisionEngine, HuggingFaceZeroShotClient, choose_mail_action
from config.settings import AppSettings


@pytest.fixture()
def client(monkeypatch, tmp_path):
    monkeypatch.chdir(tmp_path)
    settings = AppSettings(
        app_env="test",
        host="127.0.0.1",
        port=7860,
        debug=False,
        log_level="ERROR",
        default_mail_count=4,
        max_emails=10,
        model_type="rule_based",
        simulation_mode="easy",
        hf_model="facebook/bart-large-mnli",
        hf_token=None,
        hf_timeout=1.0,
        cors_origins=("*",),
        random_seed=7,
    )
    app = create_server(settings)
    app.config.update(TESTING=True)
    return app.test_client()


def test_status_returns_ok(client):
    response = client.get("/status")

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert payload["status"] == "ok"


def test_initialize_returns_valid_json_with_emails(client):
    response = client.post("/initialize", json={"count": 3})

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert len(payload["emails"]) == 3
    assert payload["state"]["current_email"]["id"] == payload["emails"][0]["id"]
    assert {"sender", "subject", "body", "processed"} <= set(payload["emails"][0])


def test_act_returns_score_and_next_state(client):
    initialized = client.post("/initialize", json={"count": 2}).get_json()
    current_email = initialized["state"]["current_email"]
    decision = choose_mail_action(current_email).to_dict()

    response = client.post("/act", json={"decision": decision})

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert "score" in payload
    assert "state" in payload
    assert payload["state"]["progress"]["processed"] == 1
    assert 0 < payload["score"]["classification_accuracy"] < 1
    assert 0 < payload["score"]["priority_correctness"] < 1
    assert "confusion_matrix" in payload["score"]


def test_invalid_input_returns_400(client):
    response = client.post("/act", json={"decision": {"mail_id": ""}})

    assert response.status_code == 400
    payload = response.get_json()
    assert payload == {
        "success": False,
        "error": "Action payload must include a non-empty email id.",
    }


def test_invalid_count_type_returns_400(client):
    response = client.post("/initialize", json={"count": "three"})

    assert response.status_code == 400
    payload = response.get_json()
    assert payload["success"] is False
    assert "count" in payload["error"]


def test_batch_act_returns_predictions(client):
    initialized = client.post("/initialize", json={"count": 2}).get_json()

    response = client.post("/act", json={"emails": initialized["emails"]})

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert payload["count"] == 2
    assert {"category", "priority", "confidence", "explanation"} <= set(
        payload["predictions"][0]
    )


def test_analytics_updates_after_action(client):
    initialized = client.post("/initialize", json={"count": 1}).get_json()
    decision = choose_mail_action(initialized["state"]["current_email"]).to_dict()
    client.post("/act", json={"decision": decision})

    response = client.get("/analytics")

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert payload["analytics"]["total_emails_processed"] == 1
    assert 0 < payload["analytics"]["average_accuracy"] < 1
    assert 0 < payload["analytics"]["average_weighted_score"] < 1


def test_leaderboard_records_completed_run(client):
    initialized = client.post("/initialize", json={"count": 1}).get_json()
    decision = choose_mail_action(initialized["state"]["current_email"]).to_dict()
    client.post("/act", json={"decision": decision})

    response = client.get("/leaderboard")

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert payload["count"] >= 1
    assert "run_id" in payload["leaderboard"][0]


def test_huggingface_mode_success_path(monkeypatch):
    class FakeClient:
        def predict(self, text):
            return "promotion", 0.87

    monkeypatch.setattr(HuggingFaceZeroShotClient, "get", lambda **kwargs: FakeClient())
    engine = DecisionEngine(model_type="huggingface")

    prediction = engine.decide(
        {
            "id": "mail_hf",
            "subject": "Member discount",
            "body": "A quiet sale is running.",
        }
    )

    assert prediction.category == "promotion"
    assert prediction.model_type == "huggingface"
    assert prediction.confidence == 0.87


def test_huggingface_mode_falls_back_without_crashing(monkeypatch):
    class FailingClient:
        def predict(self, text):
            raise RuntimeError("model unavailable")

    monkeypatch.setattr(HuggingFaceZeroShotClient, "get", lambda **kwargs: FailingClient())
    engine = DecisionEngine(model_type="huggingface")

    prediction = engine.decide(
        {
            "id": "mail_fallback",
            "subject": "Urgent response needed",
            "body": "Please reply asap.",
        }
    )

    assert prediction.category == "urgent"
    assert prediction.fallback_used is True
    assert prediction.model_type == "rule_based"


def test_health_alias_returns_ok(client):
    response = client.get("/health")

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert payload["status"] == "ok"


def test_openenv_reset_returns_observation(client):
    response = client.post("/reset?task=spam_detection")

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert payload["task"] == "spam_detection"
    assert payload["observation"]["current_email"]["email_id"]


def test_openenv_step_returns_reward_and_done(client):
    client.post("/reset?task=spam_detection")

    response = client.post(
        "/step?task=spam_detection",
        json={"classification": "spam", "team": "none", "priority": 0},
    )

    assert response.status_code == 200
    payload = response.get_json()
    assert payload["success"] is True
    assert "observation" in payload
    assert "reward" in payload
    assert "done" in payload


def test_openenv_tasks_and_state_describe_are_available(client):
    tasks_response = client.get("/tasks")
    describe_response = client.get("/state-describe?task=spam_detection")

    assert tasks_response.status_code == 200
    assert describe_response.status_code == 200
    assert len(tasks_response.get_json()["tasks"]) == 3
    describe_payload = describe_response.get_json()
    assert "action_space" in describe_payload
    assert "observation_space" in describe_payload