package service

import (
	"context"
	"testing"

	"gorm.io/gorm"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/gochat/gochat/internal/model"
)

// Helper: create prerequisite Account + Conversation + Tag for label tests
func createPrerequisitesForLabelTest(t *testing.T, db *gorm.DB, tagSvc *TagService) (uint, uint, uint) {
	t.Helper()

	// Create account
	acct := &model.Account{Name: "test-acct", Status: "active"}
	require.NoError(t, db.Create(acct).Error)

	// Create inbox (required by Conversation foreign key)
	inbox := &model.Inbox{Name: "test-inbox", AccountID: acct.ID}
	require.NoError(t, db.Create(inbox).Error)

	// Create conversation
	conv := &model.Conversation{AccountID: acct.ID, InboxID: inbox.ID, Status: "open"}
	require.NoError(t, db.Create(conv).Error)

	// Create tag
	tag, err := tagSvc.Create(context.Background(), acct.ID, &CreateTagRequest{Name: "urgent", Color: "#FF5733"})
	require.NoError(t, err)

	return acct.ID, conv.ID, tag.ID
}

// ========== LabelService AddLabelToConversation ==========

func TestLabelService_AddLabelToConversation_成功(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	accountID, convID, tagID := createPrerequisitesForLabelTest(t, db, tagSvc)

	cl, err := svc.AddLabelToConversation(context.Background(), accountID, convID, tagID)
	require.NoError(t, err)
	assert.NotZero(t, cl.ID)
	assert.Equal(t, convID, cl.ConversationID)
	assert.Equal(t, tagID, cl.TagID)
	assert.Equal(t, accountID, cl.AccountID)
}

func TestLabelService_AddLabelToConversation_重复标签(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	accountID, convID, tagID := createPrerequisitesForLabelTest(t, db, tagSvc)

	_, err := svc.AddLabelToConversation(context.Background(), accountID, convID, tagID)
	require.NoError(t, err)

	_, err = svc.AddLabelToConversation(context.Background(), accountID, convID, tagID)
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "already attached")
}

func TestLabelService_AddLabelToConversation_标签不属于账户(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	accountID, convID, tagID := createPrerequisitesForLabelTest(t, db, tagSvc)

	// Try to add tag belonging to accountID to a different account
	_, err := svc.AddLabelToConversation(context.Background(), accountID+1, convID, tagID)
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "does not belong")
}

func TestLabelService_AddLabelToConversation_标签不存在(t *testing.T) {
	_, _, _, svc := setupLabelService(t)

	_, err := svc.AddLabelToConversation(context.Background(), 1, 1, 9999)
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "tag not found")
}

// ========== LabelService RemoveLabelFromConversation ==========

func TestLabelService_RemoveLabelFromConversation_成功(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	accountID, convID, tagID := createPrerequisitesForLabelTest(t, db, tagSvc)

	_, err := svc.AddLabelToConversation(context.Background(), accountID, convID, tagID)
	require.NoError(t, err)

	err = svc.RemoveLabelFromConversation(context.Background(), convID, tagID)
	require.NoError(t, err)

	labels, err := svc.GetConversationLabels(context.Background(), convID)
	require.NoError(t, err)
	assert.Len(t, labels, 0)
}

// ========== LabelService GetConversationLabels ==========

func TestLabelService_GetConversationLabels_成功(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	accountID, convID, tagID := createPrerequisitesForLabelTest(t, db, tagSvc)

	_, err := svc.AddLabelToConversation(context.Background(), accountID, convID, tagID)
	require.NoError(t, err)

	// Create second tag and add it
	tag2, err := tagSvc.Create(context.Background(), accountID, &CreateTagRequest{Name: "feature", Color: "#00FF00"})
	require.NoError(t, err)
	_, err = svc.AddLabelToConversation(context.Background(), accountID, convID, tag2.ID)
	require.NoError(t, err)

	labels, err := svc.GetConversationLabels(context.Background(), convID)
	require.NoError(t, err)
	assert.Len(t, labels, 2)
}

// ========== LabelService ReplaceConversationLabels ==========

func TestLabelService_ReplaceConversationLabels_成功(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	accountID, convID, tagID := createPrerequisitesForLabelTest(t, db, tagSvc)

	// Add initial label
	_, err := svc.AddLabelToConversation(context.Background(), accountID, convID, tagID)
	require.NoError(t, err)

	// Create a second tag
	tag2, err := tagSvc.Create(context.Background(), accountID, &CreateTagRequest{Name: "new-label", Color: "#0000FF"})
	require.NoError(t, err)

	// Replace labels — remove old, add new
	result, err := svc.ReplaceConversationLabels(context.Background(), accountID, convID, []uint{tag2.ID})
	require.NoError(t, err)
	assert.Len(t, result, 1)
	assert.Equal(t, tag2.ID, result[0].TagID)
}

func TestLabelService_ReplaceConversationLabels_清空标签(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	accountID, convID, tagID := createPrerequisitesForLabelTest(t, db, tagSvc)

	// Add initial label
	_, err := svc.AddLabelToConversation(context.Background(), accountID, convID, tagID)
	require.NoError(t, err)

	// Replace with empty list
	result, err := svc.ReplaceConversationLabels(context.Background(), accountID, convID, []uint{})
	require.NoError(t, err)
	assert.Len(t, result, 0)
}

// ========== LabelService BatchAddLabel ==========

func TestLabelService_BatchAddLabel_成功(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	// Create account + inbox + 2 conversations + tag
	acct := &model.Account{Name: "test-acct", Status: "active"}
	require.NoError(t, db.Create(acct).Error)
	inbox := &model.Inbox{Name: "test-inbox", AccountID: acct.ID}
	require.NoError(t, db.Create(inbox).Error)
	conv1 := &model.Conversation{AccountID: acct.ID, InboxID: inbox.ID, Status: "open"}
	require.NoError(t, db.Create(conv1).Error)
	conv2 := &model.Conversation{AccountID: acct.ID, InboxID: inbox.ID, Status: "open"}
	require.NoError(t, db.Create(conv2).Error)
	tag, err := tagSvc.Create(context.Background(), acct.ID, &CreateTagRequest{Name: "bulk-tag", Color: "#123456"})
	require.NoError(t, err)

	err = svc.BatchAddLabel(context.Background(), acct.ID, &BatchAddLabelRequest{
		TagID:           tag.ID,
		ConversationIDs: []uint{conv1.ID, conv2.ID},
	})
	require.NoError(t, err)

	labels1, err := svc.GetConversationLabels(context.Background(), conv1.ID)
	require.NoError(t, err)
	assert.Len(t, labels1, 1)

	labels2, err := svc.GetConversationLabels(context.Background(), conv2.ID)
	require.NoError(t, err)
	assert.Len(t, labels2, 1)
}

// ========== LabelService BatchRemoveLabel ==========

func TestLabelService_BatchRemoveLabel_成功(t *testing.T) {
	db, _, tagRepo, svc := setupLabelService(t)
	tagSvc := NewTagService(tagRepo)

	// Create account + inbox + 2 conversations + tag
	acct := &model.Account{Name: "test-acct", Status: "active"}
	require.NoError(t, db.Create(acct).Error)
	inbox := &model.Inbox{Name: "test-inbox", AccountID: acct.ID}
	require.NoError(t, db.Create(inbox).Error)
	conv1 := &model.Conversation{AccountID: acct.ID, InboxID: inbox.ID, Status: "open"}
	require.NoError(t, db.Create(conv1).Error)
	conv2 := &model.Conversation{AccountID: acct.ID, InboxID: inbox.ID, Status: "open"}
	require.NoError(t, db.Create(conv2).Error)
	tag, err := tagSvc.Create(context.Background(), acct.ID, &CreateTagRequest{Name: "bulk-tag", Color: "#123456"})
	require.NoError(t, err)

	// First add labels
	err = svc.BatchAddLabel(context.Background(), acct.ID, &BatchAddLabelRequest{
		TagID:           tag.ID,
		ConversationIDs: []uint{conv1.ID, conv2.ID},
	})
	require.NoError(t, err)

	// Then remove them
	err = svc.BatchRemoveLabel(context.Background(), acct.ID, &BatchRemoveLabelRequest{
		TagID:           tag.ID,
		ConversationIDs: []uint{conv1.ID, conv2.ID},
	})
	require.NoError(t, err)

	labels1, err := svc.GetConversationLabels(context.Background(), conv1.ID)
	require.NoError(t, err)
	assert.Len(t, labels1, 0)

	labels2, err := svc.GetConversationLabels(context.Background(), conv2.ID)
	require.NoError(t, err)
	assert.Len(t, labels2, 0)
}