package work

import (
	"context"
	"errors"
	"testing"
	"tercul/internal/platform/config"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/suite"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"tercul/internal/app/authz"
	"tercul/internal/data/sql"
	"tercul/internal/domain"
	platform_auth "tercul/internal/platform/auth"
)

type WorkCommandsSuite struct {
	suite.Suite
	repo         *mockWorkRepository
	searchClient *mockSearchClient
	authzSvc     *authz.Service
	commands     *WorkCommands
}

func (s *WorkCommandsSuite) SetupTest() {
	s.repo = &mockWorkRepository{}
	s.searchClient = &mockSearchClient{}
	s.authzSvc = authz.NewService(s.repo, nil)
	s.commands = NewWorkCommands(s.repo, s.searchClient, s.authzSvc)
}

func TestWorkCommandsSuite(t *testing.T) {
	suite.Run(t, new(WorkCommandsSuite))
}

func (s *WorkCommandsSuite) TestCreateWork_Success() {
	work := &domain.Work{Title: "Test Work", TranslatableModel: domain.TranslatableModel{Language: "en"}}
	_, err := s.commands.CreateWork(context.Background(), work)
	assert.NoError(s.T(), err)
}

func (s *WorkCommandsSuite) TestCreateWork_Nil() {
	_, err := s.commands.CreateWork(context.Background(), nil)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestCreateWork_EmptyTitle() {
	work := &domain.Work{TranslatableModel: domain.TranslatableModel{Language: "en"}}
	_, err := s.commands.CreateWork(context.Background(), work)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestCreateWork_EmptyLanguage() {
	work := &domain.Work{Title: "Test Work"}
	_, err := s.commands.CreateWork(context.Background(), work)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestCreateWork_RepoError() {
	work := &domain.Work{Title: "Test Work", TranslatableModel: domain.TranslatableModel{Language: "en"}}
	s.repo.createFunc = func(ctx context.Context, w *domain.Work) error {
		return errors.New("db error")
	}
	_, err := s.commands.CreateWork(context.Background(), work)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestUpdateWork_Success() {
	ctx := platform_auth.ContextWithAdminUser(context.Background(), 1)
	work := &domain.Work{Title: "Test Work", TranslatableModel: domain.TranslatableModel{Language: "en"}}
	work.ID = 1

	s.repo.getByIDFunc = func(ctx context.Context, id uint) (*domain.Work, error) {
		return work, nil
	}
	s.repo.isAuthorFunc = func(ctx context.Context, workID uint, authorID uint) (bool, error) {
		return true, nil
	}

	err := s.commands.UpdateWork(ctx, work)
	assert.NoError(s.T(), err)
}

func (s *WorkCommandsSuite) TestUpdateWork_Nil() {
	err := s.commands.UpdateWork(context.Background(), nil)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestUpdateWork_ZeroID() {
	work := &domain.Work{Title: "Test Work", TranslatableModel: domain.TranslatableModel{Language: "en"}}
	err := s.commands.UpdateWork(context.Background(), work)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestUpdateWork_EmptyTitle() {
	work := &domain.Work{TranslatableModel: domain.TranslatableModel{Language: "en"}}
	work.ID = 1
	err := s.commands.UpdateWork(context.Background(), work)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestUpdateWork_EmptyLanguage() {
	work := &domain.Work{Title: "Test Work"}
	work.ID = 1
	err := s.commands.UpdateWork(context.Background(), work)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestUpdateWork_RepoError() {
	work := &domain.Work{Title: "Test Work", TranslatableModel: domain.TranslatableModel{Language: "en"}}
	work.ID = 1
	s.repo.updateFunc = func(ctx context.Context, w *domain.Work) error {
		return errors.New("db error")
	}
	err := s.commands.UpdateWork(context.Background(), work)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestDeleteWork_Success() {
	ctx := platform_auth.ContextWithAdminUser(context.Background(), 1)
	work := &domain.Work{Title: "Test Work", TranslatableModel: domain.TranslatableModel{Language: "en"}}
	work.ID = 1

	s.repo.getByIDFunc = func(ctx context.Context, id uint) (*domain.Work, error) {
		return work, nil
	}
	s.repo.isAuthorFunc = func(ctx context.Context, workID uint, authorID uint) (bool, error) {
		return true, nil
	}

	err := s.commands.DeleteWork(ctx, 1)
	assert.NoError(s.T(), err)
}

func (s *WorkCommandsSuite) TestDeleteWork_ZeroID() {
	err := s.commands.DeleteWork(context.Background(), 0)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestDeleteWork_RepoError() {
	s.repo.deleteFunc = func(ctx context.Context, id uint) error {
		return errors.New("db error")
	}
	err := s.commands.DeleteWork(context.Background(), 1)
	assert.Error(s.T(), err)
}

func (s *WorkCommandsSuite) TestAnalyzeWork_Success() {
	err := s.commands.AnalyzeWork(context.Background(), 1)
	assert.NoError(s.T(), err)
}

func TestMergeWork_Integration(t *testing.T) {
	// Setup in-memory SQLite DB
	db, err := gorm.Open(sqlite.Open("file::memory:?cache=shared"), &gorm.Config{})
	assert.NoError(t, err)

	// Run migrations for all relevant tables
	err = db.AutoMigrate(
		&domain.Work{},
		&domain.Translation{},
		&domain.Author{},
		&domain.Tag{},
		&domain.Category{},
		&domain.Copyright{},
		&domain.Monetization{},
		&domain.WorkStats{},
		&domain.WorkAuthor{},
	)
	assert.NoError(t, err)

	// Create real repositories and services pointing to the test DB
	cfg, err := config.LoadConfig()
	assert.NoError(t, err)
	workRepo := sql.NewWorkRepository(db, cfg)
	authzSvc := authz.NewService(workRepo, nil) // Using real repo for authz checks
	searchClient := &mockSearchClient{}         // Mock search client is fine
	commands := NewWorkCommands(workRepo, searchClient, authzSvc)

	// --- Seed Data ---
	author1 := &domain.Author{Name: "Author One"}
	db.Create(author1)
	author2 := &domain.Author{Name: "Author Two"}
	db.Create(author2)

	tag1 := &domain.Tag{Name: "Tag One"}
	db.Create(tag1)
	tag2 := &domain.Tag{Name: "Tag Two"}
	db.Create(tag2)

	sourceWork := &domain.Work{
		TranslatableModel: domain.TranslatableModel{Language: "en"},
		Title:             "Source Work",
		Authors:           []*domain.Author{author1},
		Tags:              []*domain.Tag{tag1},
	}
	db.Create(sourceWork)
	db.Create(&domain.Translation{Title: "Source English", Language: "en", TranslatableID: sourceWork.ID, TranslatableType: "works"})
	db.Create(&domain.Translation{Title: "Source French", Language: "fr", TranslatableID: sourceWork.ID, TranslatableType: "works"})
	db.Create(&domain.WorkStats{WorkID: sourceWork.ID, Views: 10, Likes: 5})

	targetWork := &domain.Work{
		TranslatableModel: domain.TranslatableModel{Language: "en"},
		Title:             "Target Work",
		Authors:           []*domain.Author{author2},
		Tags:              []*domain.Tag{tag2},
	}
	db.Create(targetWork)
	db.Create(&domain.Translation{Title: "Target English", Language: "en", TranslatableID: targetWork.ID, TranslatableType: "works"})
	db.Create(&domain.WorkStats{WorkID: targetWork.ID, Views: 20, Likes: 10})

	// --- Execute Merge ---
	ctx := platform_auth.ContextWithAdminUser(context.Background(), 1)
	err = commands.MergeWork(ctx, sourceWork.ID, targetWork.ID)
	assert.NoError(t, err)

	// --- Assertions ---
	// 1. Source work should be deleted
	var deletedWork domain.Work
	err = db.First(&deletedWork, sourceWork.ID).Error
	assert.Error(t, err)
	assert.True(t, errors.Is(err, gorm.ErrRecordNotFound))

	// 2. Target work should have merged data
	var finalTargetWork domain.Work
	db.Preload("Translations").Preload("Authors").Preload("Tags").First(&finalTargetWork, targetWork.ID)

	assert.Len(t, finalTargetWork.Translations, 2, "Should have two translations after merge")
	foundEn := false
	foundFr := false
	for _, tr := range finalTargetWork.Translations {
		if tr.Language == "en" {
			foundEn = true
			assert.Equal(t, "Target English", tr.Title, "Should keep target's English translation")
		}
		if tr.Language == "fr" {
			foundFr = true
			assert.Equal(t, "Source French", tr.Title, "Should merge source's French translation")
		}
	}
	assert.True(t, foundEn, "English translation should be present")
	assert.True(t, foundFr, "French translation should be present")

	assert.Len(t, finalTargetWork.Authors, 2, "Authors should be merged")
	assert.Len(t, finalTargetWork.Tags, 2, "Tags should be merged")

	// 3. Stats should be merged
	var finalStats domain.WorkStats
	db.Where("work_id = ?", targetWork.ID).First(&finalStats)
	assert.Equal(t, int64(30), finalStats.Views, "Views should be summed")
	assert.Equal(t, int64(15), finalStats.Likes, "Likes should be summed")

	// 4. Source stats should be deleted
	var deletedStats domain.WorkStats
	err = db.First(&deletedStats, "work_id = ?", sourceWork.ID).Error
	assert.Error(t, err, "Source stats should be deleted")
	assert.True(t, errors.Is(err, gorm.ErrRecordNotFound))
}