from django.contrib.auth.models import User
from django.test import TestCase

from exercise.models import Exercise
from generator.models import UserPreference
from generator.services.exercise_selector import ExerciseSelector
from registered_user.models import RegisteredUser


class TestExerciseSimilarityDedup(TestCase):
    def setUp(self):
        django_user = User.objects.create_user(
            username='similarity_dedup_user',
            password='testpass123',
        )
        registered_user = RegisteredUser.objects.create(
            user=django_user,
            first_name='Similarity',
            last_name='Dedup',
        )
        self.preference = UserPreference.objects.create(
            registered_user=registered_user,
            days_per_week=4,
            fitness_level=2,
        )

    def test_hard_similarity_blocks_near_identical_working_exercise(self):
        selector = ExerciseSelector(self.preference)
        prior = Exercise.objects.create(
            name='Posterior Chain Pull Alpha',
            movement_patterns='lower pull, lower pull - hip hinge',
            muscle_groups='glutes,hamstrings,traps',
            equipment_required='barbell',
            is_reps=True,
            is_duration=False,
            is_weight=True,
            is_compound=True,
            difficulty_level='intermediate',
        )
        candidate = Exercise.objects.create(
            name='Posterior Chain Pull Beta',
            movement_patterns='lower pull, lower pull - hip hinge',
            muscle_groups='glutes,hamstrings,traps',
            equipment_required='barbell',
            is_reps=True,
            is_duration=False,
            is_weight=True,
            is_compound=True,
            difficulty_level='intermediate',
        )

        selector.used_working_similarity_profiles.append(
            selector._build_similarity_profile(prior)
        )
        selected = selector._weighted_pick(
            Exercise.objects.filter(pk=candidate.pk),
            Exercise.objects.none(),
            count=1,
            similarity_scope='working',
        )
        self.assertEqual(
            selected,
            [],
            'Near-identical exercise should be hard-blocked in same workout.',
        )

    def test_soft_similarity_blocks_adjacent_superset_repetition(self):
        selector = ExerciseSelector(self.preference)
        previous_set_ex = Exercise.objects.create(
            name='Hip Hinge Pattern Alpha',
            movement_patterns='lower pull, lower pull - hip hinge, core',
            muscle_groups='glutes,hamstrings,core',
            equipment_required='barbell',
            is_reps=True,
            is_duration=False,
            is_weight=True,
            is_compound=True,
            difficulty_level='intermediate',
        )
        adjacent_candidate = Exercise.objects.create(
            name='Hip Hinge Pattern Beta',
            movement_patterns='lower pull - hip hinge, core',
            muscle_groups='glutes,hamstrings,core',
            equipment_required='barbell',
            is_reps=True,
            is_duration=False,
            is_weight=True,
            is_compound=True,
            difficulty_level='intermediate',
        )

        selector.last_working_similarity_profiles = [
            selector._build_similarity_profile(previous_set_ex)
        ]
        selected = selector._weighted_pick(
            Exercise.objects.filter(pk=adjacent_candidate.pk),
            Exercise.objects.none(),
            count=1,
            similarity_scope='working',
        )
        self.assertEqual(
            selected,
            [],
            'Very similar adjacent-set exercise should be soft-blocked.',
        )

    def test_dissimilar_exercise_is_allowed(self):
        selector = ExerciseSelector(self.preference)
        previous_set_ex = Exercise.objects.create(
            name='Posterior Chain Pull Alpha',
            movement_patterns='lower pull, lower pull - hip hinge, core',
            muscle_groups='glutes,hamstrings,core',
            equipment_required='barbell',
            is_reps=True,
            is_duration=False,
            is_weight=True,
            is_compound=True,
            difficulty_level='intermediate',
        )
        different_candidate = Exercise.objects.create(
            name='Horizontal Push Builder',
            movement_patterns='upper push - horizontal, upper push',
            muscle_groups='chest,triceps,deltoids',
            equipment_required='dumbbell',
            is_reps=True,
            is_duration=False,
            is_weight=True,
            is_compound=True,
            difficulty_level='intermediate',
        )

        selector.last_working_similarity_profiles = [
            selector._build_similarity_profile(previous_set_ex)
        ]
        selected = selector._weighted_pick(
            Exercise.objects.filter(pk=different_candidate.pk),
            Exercise.objects.none(),
            count=1,
            similarity_scope='working',
        )
        self.assertEqual(len(selected), 1)
        self.assertEqual(selected[0].pk, different_candidate.pk)