package repositories_test

import (
	"context"
	"encoding/json"
	"errors"
	"testing"
	"time"

	"tercul/internal/testutil"
	"tercul/models"
	"tercul/repositories"

	"github.com/stretchr/testify/suite"
)

// ErrCacheMiss is returned when a key is not found in the cache
var ErrCacheMiss = errors.New("cache miss")

// MarshalValue marshals a value to JSON
func MarshalValue(value interface{}) ([]byte, error) {
	return json.Marshal(value)
}

// UnmarshalValue unmarshals a value from JSON
func UnmarshalValue(data []byte, value interface{}) error {
	return json.Unmarshal(data, value)
}

// testCache is a simple in-memory cache for testing
type testCache struct {
	data map[string][]byte
}

func (c *testCache) Get(ctx context.Context, key string, value interface{}) error {
	data, ok := c.data[key]
	if !ok {
		return ErrCacheMiss
	}

	return UnmarshalValue(data, value)
}

func (c *testCache) Set(ctx context.Context, key string, value interface{}, expiration time.Duration) error {
	data, err := MarshalValue(value)
	if err != nil {
		return err
	}

	c.data[key] = data
	return nil
}

func (c *testCache) Delete(ctx context.Context, key string) error {
	delete(c.data, key)
	return nil
}

func (c *testCache) Clear(ctx context.Context) error {
	c.data = make(map[string][]byte)
	return nil
}

func (c *testCache) GetMulti(ctx context.Context, keys []string) (map[string][]byte, error) {
	result := make(map[string][]byte)
	for _, key := range keys {
		if data, ok := c.data[key]; ok {
			result[key] = data
		}
	}
	return result, nil
}

func (c *testCache) SetMulti(ctx context.Context, items map[string]interface{}, expiration time.Duration) error {
	for key, value := range items {
		data, err := MarshalValue(value)
		if err != nil {
			return err
		}
		c.data[key] = data
	}
	return nil
}

// MockWorkRepository for testing
type MockWorkRepository struct {
	works []*models.Work
}

func NewMockWorkRepository() *MockWorkRepository {
	return &MockWorkRepository{works: []*models.Work{}}
}

func (m *MockWorkRepository) AddWork(work *models.Work) {
	work.ID = uint(len(m.works) + 1)
	m.works = append(m.works, work)
}

func (m *MockWorkRepository) GetByID(id uint) (*models.Work, error) {
	for _, w := range m.works {
		if w.ID == id {
			return w, nil
		}
	}
	return nil, errors.New("not found")
}

func (m *MockWorkRepository) FindByTitle(title string) ([]*models.Work, error) {
	var result []*models.Work
	for _, w := range m.works {
		if len(title) == 0 || (len(w.Title) >= len(title) && w.Title[:len(title)] == title) {
			result = append(result, w)
		}
	}
	return result, nil
}

func (m *MockWorkRepository) FindByLanguage(language string, page, pageSize int) (*repositories.PaginatedResult[*models.Work], error) {
	var filtered []*models.Work
	for _, w := range m.works {
		if w.Language == language {
			filtered = append(filtered, w)
		}
	}
	total := int64(len(filtered))
	start := (page - 1) * pageSize
	end := start + pageSize
	if start > len(filtered) {
		return &repositories.PaginatedResult[*models.Work]{Items: []*models.Work{}, TotalCount: total}, nil
	}
	if end > len(filtered) {
		end = len(filtered)
	}
	return &repositories.PaginatedResult[*models.Work]{Items: filtered[start:end], TotalCount: total}, nil
}

func (m *MockWorkRepository) Count() (int64, error) {
	return int64(len(m.works)), nil
}

// CachedWorkRepositorySuite is a test suite for the CachedWorkRepository
// Refactored to use MockWorkRepository and in-memory cache

type CachedWorkRepositorySuite struct {
	suite.Suite
	baseRepo *testutil.UnifiedMockWorkRepository
	cache    *testCache
	repo     *repositories.CachedWorkRepository
}

func (s *CachedWorkRepositorySuite) SetupSuite() {
	// No DB setup required
}

func (s *CachedWorkRepositorySuite) SetupTest() {
	s.baseRepo = testutil.NewUnifiedMockWorkRepository()
	s.cache = &testCache{data: make(map[string][]byte)}

	s.repo = repositories.NewCachedWorkRepository(
		s.baseRepo,
		s.cache,
		nil,
		30*time.Minute,
	)
}

// createTestWork creates a test work and adds it to the mock repo
func (s *CachedWorkRepositorySuite) createTestWork(title, language string) *models.Work {
	work := &models.Work{
		TranslatableModel: models.TranslatableModel{BaseModel: models.BaseModel{ID: 0}, Language: language},
		Title:             title,
		Description:       "Test description",
		Status:            "published",
	}
	s.baseRepo.AddWork(work)
	return work
}

// TestGetByID tests the GetByID method with cache miss and hit
func (s *CachedWorkRepositorySuite) TestGetByID() {
	work := s.createTestWork("Test Work", "en")

    result1, err := s.repo.GetByID(context.Background(), work.ID)
	s.Require().NoError(err)
	s.Require().NotNil(result1)
	s.Equal(work.ID, result1.ID)
	s.Equal(work.Title, result1.Title)

    result2, err := s.repo.GetByID(context.Background(), work.ID)
	s.Require().NoError(err)
	s.Require().NotNil(result2)
	s.Equal(work.ID, result2.ID)
	s.Equal(work.Title, result2.Title)

	s.Equal(result1.ID, result2.ID)
	s.Equal(result1.Title, result2.Title)
}

// TestFindByTitle tests the FindByTitle method
func (s *CachedWorkRepositorySuite) TestFindByTitle() {
	work1 := s.createTestWork("Test Work 1", "en")
	work2 := s.createTestWork("Test Work 2", "en")
	_ = s.createTestWork("Another Work", "en")

    works1, err := s.repo.FindByTitle(context.Background(), "Test")
	s.Require().NoError(err)
	s.Require().Len(works1, 2)

    works2, err := s.repo.FindByTitle(context.Background(), "Test")
	s.Require().NoError(err)
	s.Require().Len(works2, 2)

	foundWork1 := false
	foundWork2 := false
	for _, work := range works2 {
		if work.ID == work1.ID {
			foundWork1 = true
		}
		if work.ID == work2.ID {
			foundWork2 = true
		}
	}
	s.True(foundWork1)
	s.True(foundWork2)
}

// TestFindByLanguage tests the FindByLanguage method
func (s *CachedWorkRepositorySuite) TestFindByLanguage() {
	s.createTestWork("Work 1", "en")
	s.createTestWork("Work 2", "en")
	s.createTestWork("Work 3", "fr")
	s.createTestWork("Work 4", "fr")
	s.createTestWork("Work 5", "es")

    result1, err := s.repo.FindByLanguage(context.Background(), "en", 1, 10)
	s.Require().NoError(err)
	s.Require().NotNil(result1)
	s.Equal(int64(2), result1.TotalCount)
	s.Equal(2, len(result1.Items))

    result2, err := s.repo.FindByLanguage(context.Background(), "en", 1, 10)
	s.Require().NoError(err)
	s.Require().NotNil(result2)
	s.Equal(int64(2), result2.TotalCount)
	s.Equal(2, len(result2.Items))
}

// TestCachedWorkRepositorySuite runs the test suite
func TestCachedWorkRepositorySuite(t *testing.T) {
	suite.Run(t, new(CachedWorkRepositorySuite))
}