"""
Tests for the unified recommendation scoring (B3).

Covers the shared scorer directly, the dict-based alias entry point, and the
/api/v1/stats/recommendation endpoint that now delegates to it.
"""
import pytest
from fastapi.testclient import TestClient

from backend.main import app
from services.recommendation_service import (
    HIGH_PRIORITY_TEXT,
    NORMAL_PRIORITY_TEXT,
    get_statistical_recommendation,
    score_recommendation,
)

client = TestClient(app)


class TestScoreRecommendation:
    """Weights and threshold of the shared scorer."""

    def test_empty_case_scores_zero(self):
        result = score_recommendation()
        assert result['score'] == 0
        assert result['priority'] == 'normal'
        assert result['recommendation'] == NORMAL_PRIORITY_TEXT

    def test_young_child(self):
        assert score_recommendation(age=8)['score'] == 20

    def test_age_at_threshold_not_counted(self):
        assert score_recommendation(age=12)['score'] == 0

    def test_long_elapsed(self):
        assert score_recommendation(elapsed_hours=12)['score'] == 20

    def test_short_elapsed_not_counted(self):
        assert score_recommendation(elapsed_hours=11)['score'] == 0

    def test_risky_terrain(self):
        assert score_recommendation(terrain='лес')['score'] == 15

    def test_adverse_weather(self):
        assert score_recommendation(weather='дождь')['score'] == 15

    def test_multiple_health_flags(self):
        assert score_recommendation(health_flags=['эпилепсия', 'РАС'])['score'] == 15

    def test_single_health_flag_not_counted(self):
        assert score_recommendation(health_flags=['эпилепсия'])['score'] == 0

    def test_terrain_matches_as_substring(self):
        """Substring match — the router previously required an exact match."""
        assert score_recommendation(terrain='смешанный лес')['score'] == 15

    def test_weather_matches_as_substring(self):
        assert score_recommendation(weather='сильный дождь')['score'] == 15

    def test_terrain_case_insensitive(self):
        assert score_recommendation(terrain='ЛЕС')['score'] == 15

    def test_unknown_terrain_scores_zero(self):
        assert score_recommendation(terrain='поле')['score'] == 0

    def test_high_priority_at_threshold(self):
        result = score_recommendation(age=8, elapsed_hours=14)
        assert result['score'] == 40
        assert result['priority'] == 'high'
        assert result['recommendation'] == HIGH_PRIORITY_TEXT

    def test_just_below_threshold_is_normal(self):
        result = score_recommendation(age=8, terrain='лес')
        assert result['score'] == 35
        assert result['priority'] == 'normal'

    def test_all_factors(self):
        result = score_recommendation(
            age=6,
            elapsed_hours=24,
            terrain='болото',
            weather='туман',
            health_flags=['РАС', 'эпилепсия'],
        )
        assert result['score'] == 85
        assert result['priority'] == 'high'


class TestGetStatisticalRecommendation:
    """Dict entry point and its field aliases."""

    def test_age_alias(self):
        assert get_statistical_recommendation({'age_years': 8})['score'] == 20

    def test_age_preferred_over_alias(self):
        assert get_statistical_recommendation({'age': 8, 'age_years': 30})['score'] == 20

    def test_terrain_alias(self):
        assert get_statistical_recommendation({'terrain_primary': 'лес'})['score'] == 15

    def test_weather_alias(self):
        assert get_statistical_recommendation({'precipitation': 'снег'})['score'] == 15

    def test_health_flags_counted(self):
        payload = {'health_flags': ['РАС', 'эпилепсия']}
        assert get_statistical_recommendation(payload)['score'] == 15

    def test_missing_keys_are_safe(self):
        assert get_statistical_recommendation({})['score'] == 0

    def test_none_values_are_safe(self):
        payload = {'age': None, 'elapsed_hours': None, 'terrain': None, 'weather': None}
        assert get_statistical_recommendation(payload)['score'] == 0


class TestRecommendationEndpoint:
    """The endpoint keeps its response contract while delegating."""

    def test_returns_score_and_recommendation(self):
        response = client.post(
            '/api/v1/stats/recommendation',
            json={'age': 8, 'elapsed_hours': 14},
        )
        assert response.status_code == 200
        body = response.json()
        assert body['score'] == 40
        assert body['recommendation'] == HIGH_PRIORITY_TEXT

    def test_normal_priority_case(self):
        response = client.post('/api/v1/stats/recommendation', json={'age': 30})
        assert response.status_code == 200
        body = response.json()
        assert body['score'] == 0
        assert body['recommendation'] == NORMAL_PRIORITY_TEXT

    def test_empty_payload_accepted(self):
        response = client.post('/api/v1/stats/recommendation', json={})
        assert response.status_code == 200
        assert response.json()['score'] == 0

    def test_endpoint_matches_shared_scorer(self):
        payload = {
            'age': 6,
            'elapsed_hours': 24,
            'terrain_primary': 'болото',
            'weather': 'туман',
            'health_flags': ['РАС', 'эпилепсия'],
        }
        response = client.post('/api/v1/stats/recommendation', json=payload)
        assert response.status_code == 200

        expected = score_recommendation(
            age=payload['age'],
            elapsed_hours=payload['elapsed_hours'],
            terrain=payload['terrain_primary'],
            weather=payload['weather'],
            health_flags=payload['health_flags'],
        )
        assert response.json()['score'] == expected['score']
        assert response.json()['recommendation'] == expected['recommendation']