package service

import (
	"context"
	"fmt"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"

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

// ========== Test Setup ==========

func setupAgentBotInboxService(t *testing.T) (*AgentBotInboxService, *gorm.DB) {
	t.Helper()

	db, err := gorm.Open(sqlite.Open("file::memory:"), &gorm.Config{
		Logger: logger.Default.LogMode(logger.Silent),
	})
	require.NoError(t, err, "failed to open SQLite test db")

	require.NoError(t, db.AutoMigrate(
		&model.Account{},
		&model.AgentBot{},
		&model.Inbox{},
		&model.AgentBotInbox{},
	), "failed to auto-migrate")

	t.Cleanup(func() {
		sqlDB, _ := db.DB()
		sqlDB.Close()
	})

	repo := repository.NewAgentBotInboxRepo(db)
	botRepo := repository.NewAgentBotRepo(db)
	svc := NewAgentBotInboxService(repo, botRepo)
	return svc, db
}

// Helper: create prerequisite Account, AgentBot, and Inbox for service tests.
func createSvcPrereqs(t *testing.T, db *gorm.DB) (*model.Account, *model.AgentBot, *model.Inbox) {
	t.Helper()

	account := &model.Account{Name: "SvcTestOrg", Locale: "en", Active: true}
	require.NoError(t, db.Create(account).Error)

	bot := &model.AgentBot{
		AccountID:   &account.ID,
		Name:        "SvcTestBot",
		BotType:     "default",
		Secret:      "secret-svcbot",
		AccessToken: "token-svcbot",
	}
	require.NoError(t, db.Create(bot).Error)

	inbox := &model.Inbox{
		AccountID:   account.ID,
		Name:        "SvcTestInbox",
		ChannelType: "web_widget",
		ChannelID:   1,
	}
	require.NoError(t, db.Create(inbox).Error)

	return account, bot, inbox
}

// Helper: create a second bot with unique secret/token for SQLite UNIQUE constraint.
func createSvcSecondBot(t *testing.T, db *gorm.DB, accountID uint, suffix string) *model.AgentBot {
	t.Helper()

	bot := &model.AgentBot{
		AccountID:   &accountID,
		Name:        "SvcBot-" + suffix,
		BotType:     "default",
		Secret:      fmt.Sprintf("secret-svc-%s", suffix),
		AccessToken: fmt.Sprintf("token-svc-%s", suffix),
	}
	require.NoError(t, db.Create(bot).Error)
	return bot
}

// ========== 1. Bind ==========

func TestAgentBotInboxService_Bind(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, inbox := createSvcPrereqs(t, db)

	abi, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	require.NoError(t, err)
	assert.NotZero(t, abi.ID)
	assert.Equal(t, bot.ID, abi.AgentBotID)
	assert.Equal(t, inbox.ID, abi.InboxID)
	assert.Equal(t, model.AgentBotInboxActive, abi.Status)
}

func TestAgentBotInboxService_Bind_BotNotFound(t *testing.T) {
	svc, _ := setupAgentBotInboxService(t)

	abi, err := svc.Bind(context.Background(), 1, BindBotToInboxRequest{
		AgentBotID: 9999,
		InboxID:    1,
	})
	assert.Error(t, err)
	assert.Nil(t, abi)
	assert.Contains(t, err.Error(), "agent bot not found")
}

func TestAgentBotInboxService_Bind_Duplicate(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, inbox := createSvcPrereqs(t, db)

	// First bind succeeds
	_, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	require.NoError(t, err)

	// Second bind fails (duplicate)
	abi, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	assert.Error(t, err)
	assert.Nil(t, abi)
	assert.Contains(t, err.Error(), "already bound")
}

// ========== 2. Unbind ==========

func TestAgentBotInboxService_Unbind(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, inbox := createSvcPrereqs(t, db)

	abi, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	require.NoError(t, err)

	err = svc.Unbind(context.Background(), abi.ID)
	assert.NoError(t, err)

	// Verify binding is gone
	abis, err := svc.ListByInbox(context.Background(), inbox.ID)
	assert.NoError(t, err)
	assert.Len(t, abis, 0)
}

func TestAgentBotInboxService_Unbind_NotFound(t *testing.T) {
	svc, _ := setupAgentBotInboxService(t)

	err := svc.Unbind(context.Background(), 9999)
	assert.NoError(t, err) // GORM delete on non-existent row returns no error
}

// ========== 3. UpdateStatus ==========

func TestAgentBotInboxService_UpdateStatus(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, inbox := createSvcPrereqs(t, db)

	abi, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	require.NoError(t, err)
	assert.Equal(t, model.AgentBotInboxActive, abi.Status)

	// Toggle to inactive
	updated, err := svc.UpdateStatus(context.Background(), abi.ID, UpdateBindingStatusRequest{Status: 1})
	require.NoError(t, err)
	assert.Equal(t, model.AgentBotInboxInactive, updated.Status)

	// Toggle back to active
	updated2, err := svc.UpdateStatus(context.Background(), abi.ID, UpdateBindingStatusRequest{Status: 0})
	require.NoError(t, err)
	assert.Equal(t, model.AgentBotInboxActive, updated2.Status)
}

func TestAgentBotInboxService_UpdateStatus_NotFound(t *testing.T) {
	svc, _ := setupAgentBotInboxService(t)

	abi, err := svc.UpdateStatus(context.Background(), 9999, UpdateBindingStatusRequest{Status: 1})
	assert.Error(t, err)
	assert.Nil(t, abi)
	assert.Contains(t, err.Error(), "binding not found")
}

// ========== 4. ListByInbox ==========

func TestAgentBotInboxService_ListByInbox(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, inbox := createSvcPrereqs(t, db)

	_, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	require.NoError(t, err)

	abis, err := svc.ListByInbox(context.Background(), inbox.ID)
	assert.NoError(t, err)
	assert.Len(t, abis, 1)
	assert.Equal(t, bot.ID, abis[0].AgentBotID)
}

func TestAgentBotInboxService_ListByInbox_Empty(t *testing.T) {
	svc, _ := setupAgentBotInboxService(t)

	abis, err := svc.ListByInbox(context.Background(), 9999)
	assert.NoError(t, err)
	assert.Len(t, abis, 0)
}

// ========== 5. ListActiveByInbox ==========

func TestAgentBotInboxService_ListActiveByInbox(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, inbox := createSvcPrereqs(t, db)

	abi, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	require.NoError(t, err)

	// Initially active
	abis, err := svc.ListActiveByInbox(context.Background(), inbox.ID)
	assert.NoError(t, err)
	assert.Len(t, abis, 1)

	// Toggle to inactive
	_, err = svc.UpdateStatus(context.Background(), abi.ID, UpdateBindingStatusRequest{Status: 1})
	require.NoError(t, err)

	// No active bindings now
	abis, err = svc.ListActiveByInbox(context.Background(), inbox.ID)
	assert.NoError(t, err)
	assert.Len(t, abis, 0)

	// But ListByInbox still shows 1
	allAbis, err := svc.ListByInbox(context.Background(), inbox.ID)
	assert.NoError(t, err)
	assert.Len(t, allAbis, 1)
}

// ========== 6. ListByBot ==========

func TestAgentBotInboxService_ListByBot(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, inbox := createSvcPrereqs(t, db)

	_, err := svc.Bind(context.Background(), inbox.AccountID, BindBotToInboxRequest{
		AgentBotID: bot.ID,
		InboxID:    inbox.ID,
	})
	require.NoError(t, err)

	abis, err := svc.ListByBot(context.Background(), bot.ID)
	assert.NoError(t, err)
	assert.Len(t, abis, 1)
	assert.Equal(t, inbox.ID, abis[0].InboxID)
}

func TestAgentBotInboxService_ListByBot_Empty(t *testing.T) {
	svc, db := setupAgentBotInboxService(t)
	_, bot, _ := createSvcPrereqs(t, db)

	abis, err := svc.ListByBot(context.Background(), bot.ID)
	assert.NoError(t, err)
	assert.Len(t, abis, 0)
}