from datetime import date

from django.test import TestCase
from django.contrib.auth.models import User
from rest_framework.test import APIClient
from rest_framework.authtoken.models import Token

from registered_user.models import RegisteredUser
from generator.models import UserPreference, WorkoutType


class TestInjurySafety(TestCase):
    """Tests for injury-related preference round-trip and warning generation."""

    def setUp(self):
        self.django_user = User.objects.create_user(
            username='testuser',
            password='testpass123',
            email='test@example.com',
        )
        self.registered_user = RegisteredUser.objects.create(
            user=self.django_user,
            first_name='Test',
            last_name='User',
        )
        self.token = Token.objects.create(user=self.django_user)
        self.client = APIClient()
        self.client.credentials(HTTP_AUTHORIZATION=f'Token {self.token.key}')
        self.preference = UserPreference.objects.create(
            registered_user=self.registered_user,
            days_per_week=3,
        )
        # Create a basic workout type for generation
        self.workout_type = WorkoutType.objects.create(
            name='functional_strength_training',
            display_name='Functional Strength',
            typical_rest_between_sets=60,
            typical_intensity='medium',
            rep_range_min=8,
            rep_range_max=12,
            round_range_min=3,
            round_range_max=4,
            duration_bias=0.3,
            superset_size_min=2,
            superset_size_max=4,
        )

    def test_injury_types_roundtrip(self):
        """PUT injury_types, GET back, verify data persists."""
        injuries = [
            {'type': 'knee', 'severity': 'moderate'},
            {'type': 'shoulder', 'severity': 'mild'},
        ]
        response = self.client.put(
            '/generator/preferences/update/',
            {'injury_types': injuries},
            format='json',
        )
        self.assertEqual(response.status_code, 200)

        # GET back
        response = self.client.get('/generator/preferences/')
        self.assertEqual(response.status_code, 200)
        data = response.json()
        self.assertEqual(len(data['injury_types']), 2)
        types_set = {i['type'] for i in data['injury_types']}
        self.assertIn('knee', types_set)
        self.assertIn('shoulder', types_set)

    def test_injury_types_validation_rejects_invalid_type(self):
        """Invalid injury type should be rejected."""
        response = self.client.put(
            '/generator/preferences/update/',
            {'injury_types': [{'type': 'elbow', 'severity': 'mild'}]},
            format='json',
        )
        self.assertEqual(response.status_code, 400)

    def test_injury_types_validation_rejects_invalid_severity(self):
        """Invalid severity should be rejected."""
        response = self.client.put(
            '/generator/preferences/update/',
            {'injury_types': [{'type': 'knee', 'severity': 'extreme'}]},
            format='json',
        )
        self.assertEqual(response.status_code, 400)

    def test_severe_knee_excludes_high_impact(self):
        """Set knee:severe, verify the exercise selector filters correctly."""
        from generator.services.exercise_selector import ExerciseSelector

        self.preference.injury_types = [
            {'type': 'knee', 'severity': 'severe'},
        ]
        self.preference.save()

        selector = ExerciseSelector(self.preference)
        qs = selector._get_filtered_queryset()

        # No high-impact exercises should remain
        high_impact = qs.filter(impact_level='high')
        self.assertEqual(high_impact.count(), 0)

        # No medium-impact exercises either (severe lower body)
        medium_impact = qs.filter(impact_level='medium')
        self.assertEqual(medium_impact.count(), 0)

        # Warnings should mention the injury
        self.assertTrue(
            any('knee' in w.lower() for w in selector.warnings),
            f'Expected knee-related warning, got: {selector.warnings}'
        )

    def test_no_injuries_full_pool(self):
        """Empty injury_types should not exclude any exercises."""
        from generator.services.exercise_selector import ExerciseSelector

        self.preference.injury_types = []
        self.preference.save()

        selector = ExerciseSelector(self.preference)
        qs = selector._get_filtered_queryset()

        # With no injuries, there should be no injury-based warnings
        injury_warnings = [w for w in selector.warnings if 'injury' in w.lower()]
        self.assertEqual(len(injury_warnings), 0)

    def test_warnings_in_preview_response(self):
        """With injuries set, verify warnings key appears in preview response."""
        self.preference.injury_types = [
            {'type': 'knee', 'severity': 'moderate'},
        ]
        self.preference.save()
        self.preference.preferred_workout_types.add(self.workout_type)

        response = self.client.post(
            '/generator/preview/',
            {'week_start_date': '2026-03-02'},
            format='json',
        )
        # Should succeed (200) even if exercise pool is limited
        self.assertIn(response.status_code, [200, 500])
        if response.status_code == 200:
            data = response.json()
            # The warnings key should exist if injuries triggered any warnings
            if 'warnings' in data:
                self.assertIsInstance(data['warnings'], list)

    def test_backward_compat_string_injuries(self):
        """Legacy string format should be accepted and normalized."""
        response = self.client.put(
            '/generator/preferences/update/',
            {'injury_types': ['knee', 'shoulder']},
            format='json',
        )
        self.assertEqual(response.status_code, 200)

        # Verify normalized to dict format
        response = self.client.get('/generator/preferences/')
        data = response.json()
        for injury in data['injury_types']:
            self.assertIn('type', injury)
            self.assertIn('severity', injury)
            self.assertEqual(injury['severity'], 'moderate')