package services_test

import (
	"strings"
	"sync"
	"testing"
	"time"

	"code.tczkiot.com/wlw/ai-agent/internal/models"
	"code.tczkiot.com/wlw/ai-agent/internal/pkg/dto"
	"code.tczkiot.com/wlw/ai-agent/internal/pkg/enums"
	"code.tczkiot.com/wlw/ai-agent/internal/pkg/openidentity"
	"code.tczkiot.com/wlw/ai-agent/internal/services"

	"github.com/glebarez/sqlite"
	"github.com/mlogclub/simple/sqls"
	"gorm.io/gorm"
	"gorm.io/gorm/schema"
)

func TestConversationHumanDispatchAIHandoffOffHoursKeepsAIServingAndSendsNotice(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	aiAgent := createHumanDispatchAIAgent(t, db, enums.IMConversationServiceModeAIFirst, "1")
	conversation := createHumanDispatchConversation(t, db, aiAgent.ID, enums.IMConversationStatusAIServing)

	result, err := services.ConversationHumanDispatchService.HandoffByAI(conversation.ID, aiAgent, "用户要求转人工")
	if err != nil {
		t.Fatalf("HandoffByAI() error = %v", err)
	}
	if result == nil || result.Decision != services.HandoffDecisionOffHours {
		t.Fatalf("expected off_hours decision, got %+v", result)
	}

	current := services.ConversationService.Get(conversation.ID)
	if current.Status != enums.IMConversationStatusAIServing {
		t.Fatalf("expected conversation to stay AI serving, got status=%d", current.Status)
	}
	if current.HandoffAt != nil {
		t.Fatalf("expected handoffAt to stay nil, got %v", current.HandoffAt)
	}

	message := services.MessageService.FindOne(sqls.NewCnd().Eq("conversation_id", conversation.ID).Desc("id"))
	if message == nil {
		t.Fatalf("expected off-hours notice message")
	}
	if message.SenderType != enums.IMSenderTypeAI || message.Content != services.HandoffOffHoursMessage {
		t.Fatalf("unexpected off-hours message: %+v", message)
	}
}

func TestConversationHumanDispatchAIHandoffAssignsAvailableAgent(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	aiAgent := createHumanDispatchAIAgent(t, db, enums.IMConversationServiceModeAIFirst, "1")
	createHumanDispatchTeam(t, db, 1, "售后支持组")
	createHumanDispatchActiveSchedule(t, db, 1)
	createHumanDispatchAgentProfile(t, db, 101, 1, enums.ServiceStatusIdle, 3, true, enums.StatusOk)
	conversation := createHumanDispatchConversation(t, db, aiAgent.ID, enums.IMConversationStatusAIServing)

	result, err := services.ConversationHumanDispatchService.HandoffByAI(conversation.ID, aiAgent, "用户要求转人工")
	if err != nil {
		t.Fatalf("HandoffByAI() error = %v", err)
	}
	if result == nil || result.Decision != services.HandoffDecisionAssigned {
		t.Fatalf("expected assigned decision, got %+v", result)
	}

	current := services.ConversationService.Get(conversation.ID)
	if current.Status != enums.IMConversationStatusActive {
		t.Fatalf("expected active conversation, got status=%d", current.Status)
	}
	if current.CurrentAssigneeID != 101 || current.CurrentTeamID != 1 {
		t.Fatalf("unexpected assignment: assignee=%d team=%d", current.CurrentAssigneeID, current.CurrentTeamID)
	}
	if current.HandoffAt == nil || current.HandoffReason != "用户要求转人工" {
		t.Fatalf("expected handoff metadata, got at=%v reason=%q", current.HandoffAt, current.HandoffReason)
	}
}

func TestConversationHumanDispatchAIHandoffFallsBackToFirstScheduledTeam(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	aiAgent := createHumanDispatchAIAgent(t, db, enums.IMConversationServiceModeAIFirst, "3,1,2")
	createHumanDispatchTeam(t, db, 1, "售后支持组")
	createHumanDispatchTeam(t, db, 2, "VIP支持组")
	createHumanDispatchTeam(t, db, 3, "非值班组")
	createHumanDispatchActiveSchedule(t, db, 1)
	createHumanDispatchActiveSchedule(t, db, 2)
	conversation := createHumanDispatchConversation(t, db, aiAgent.ID, enums.IMConversationStatusAIServing)

	result, err := services.ConversationHumanDispatchService.HandoffByAI(conversation.ID, aiAgent, "用户要求转人工")
	if err != nil {
		t.Fatalf("HandoffByAI() error = %v", err)
	}
	if result == nil || result.Decision != services.HandoffDecisionTeamPool {
		t.Fatalf("expected team_pool decision, got %+v", result)
	}

	current := services.ConversationService.Get(conversation.ID)
	if current.Status != enums.IMConversationStatusPending {
		t.Fatalf("expected pending conversation, got status=%d", current.Status)
	}
	if current.CurrentTeamID != 1 || current.CurrentAssigneeID != 0 {
		t.Fatalf("expected fallback team 1 with no assignee, got team=%d assignee=%d", current.CurrentTeamID, current.CurrentAssigneeID)
	}
}

func TestConversationHumanDispatchHumanOnlyCreateOffHoursUsesGlobalPendingPool(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	aiAgent := createHumanDispatchAIAgent(t, db, enums.IMConversationServiceModeHumanOnly, "1")

	conversation, err := services.ConversationService.Create(openidentity.ExternalUser{
		ExternalSource: enums.ExternalSourceGuest,
		ExternalID:     "guest-human-only-off-hours",
		ExternalName:   "非服务时间访客",
	}, 1, aiAgent.ID)
	if err != nil {
		t.Fatalf("Create() error = %v", err)
	}
	if conversation.Status != enums.IMConversationStatusPending {
		t.Fatalf("expected pending conversation, got status=%d", conversation.Status)
	}
	if conversation.CurrentTeamID != 0 || conversation.CurrentAssigneeID != 0 {
		t.Fatalf("expected global pending pool, got team=%d assignee=%d", conversation.CurrentTeamID, conversation.CurrentAssigneeID)
	}

	message := services.MessageService.FindOne(sqls.NewCnd().Eq("conversation_id", conversation.ID).Desc("id"))
	if message == nil || message.Content != services.HandoffWaitingMessage {
		t.Fatalf("expected waiting message, got %+v", message)
	}
}

func TestConversationHumanDispatchHumanOnlyCreateAssignsAvailableAgent(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	aiAgent := createHumanDispatchAIAgent(t, db, enums.IMConversationServiceModeHumanOnly, "1")
	createHumanDispatchTeam(t, db, 1, "售后支持组")
	createHumanDispatchActiveSchedule(t, db, 1)
	createHumanDispatchAgentProfile(t, db, 101, 1, enums.ServiceStatusIdle, 3, true, enums.StatusOk)

	conversation, err := services.ConversationService.Create(openidentity.ExternalUser{
		ExternalSource: enums.ExternalSourceGuest,
		ExternalID:     "guest-human-only-assigned",
		ExternalName:   "服务时间访客",
	}, 1, aiAgent.ID)
	if err != nil {
		t.Fatalf("Create() error = %v", err)
	}
	if conversation.Status != enums.IMConversationStatusActive {
		t.Fatalf("expected active conversation, got status=%d", conversation.Status)
	}
	if conversation.CurrentAssigneeID != 101 || conversation.CurrentTeamID != 1 {
		t.Fatalf("unexpected assignment: assignee=%d team=%d", conversation.CurrentAssigneeID, conversation.CurrentTeamID)
	}
}

func TestConversationAutoAssignManualDispatchOffHoursReturnsBusinessMessage(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	aiAgent := createHumanDispatchAIAgent(t, db, enums.IMConversationServiceModeAIFirst, "1")
	conversation := createHumanDispatchConversation(t, db, aiAgent.ID, enums.IMConversationStatusPending)

	err := services.ConversationService.AutoAssignConversation(conversation.ID, testHumanDispatchOperator())
	if err == nil {
		t.Fatalf("expected off-hours manual dispatch to fail")
	}
	if !strings.Contains(err.Error(), "当前暂不在人工客服服务时间内") {
		t.Fatalf("expected off-hours error, got %v", err)
	}
}

func TestConversationAutoAssignManualDispatchFallsBackToTeamPool(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	aiAgent := createHumanDispatchAIAgent(t, db, enums.IMConversationServiceModeAIFirst, "1")
	createHumanDispatchTeam(t, db, 1, "售后支持组")
	createHumanDispatchActiveSchedule(t, db, 1)
	conversation := createHumanDispatchConversation(t, db, aiAgent.ID, enums.IMConversationStatusPending)

	err := services.ConversationService.AutoAssignConversation(conversation.ID, testHumanDispatchOperator())
	if err != nil {
		t.Fatalf("AutoAssignConversation() error = %v", err)
	}
	current := services.ConversationService.Get(conversation.ID)
	if current.Status != enums.IMConversationStatusPending || current.CurrentTeamID != 1 || current.CurrentAssigneeID != 0 {
		t.Fatalf("expected team-pool pending conversation, got %+v", current)
	}
}

func TestConversationQueueOrdersByEffectivePriorityThenFIFO(t *testing.T) {
	setupConversationHumanDispatchTestDB(t)
	now := time.Now().Truncate(time.Second)
	oldest := now.Add(-6 * time.Minute)
	middle := now.Add(-2 * time.Minute)
	newest := now.Add(-time.Minute)
	queue := []models.Conversation{
		{ID: 1, Status: enums.IMConversationStatusPending, Priority: 0, QueueEnteredAt: &middle},
		{ID: 2, Status: enums.IMConversationStatusPending, Priority: 1, QueueEnteredAt: &newest},
		{ID: 3, Status: enums.IMConversationStatusPending, Priority: 0, QueueEnteredAt: &oldest},
	}

	services.ConversationQueueService.Sort(queue, now)
	if queue[0].ID != 3 || queue[1].ID != 2 || queue[2].ID != 1 {
		t.Fatalf("unexpected queue order: %d, %d, %d", queue[0].ID, queue[1].ID, queue[2].ID)
	}
	if level := services.ConversationQueueService.EscalationLevel(&queue[0], now); level != 1 {
		t.Fatalf("expected timeout escalation level 1, got %d", level)
	}
}

func TestConversationQueueSnapshotSeparatesTeamPools(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	now := time.Now().Truncate(time.Second)
	firstEnteredAt := now.Add(-3 * time.Minute)
	secondEnteredAt := now.Add(-2 * time.Minute)
	otherPoolEnteredAt := now.Add(-10 * time.Minute)
	first := models.Conversation{Status: enums.IMConversationStatusPending, CurrentTeamID: 1, QueueEnteredAt: &firstEnteredAt}
	second := models.Conversation{Status: enums.IMConversationStatusPending, CurrentTeamID: 1, QueueEnteredAt: &secondEnteredAt}
	otherPool := models.Conversation{Status: enums.IMConversationStatusPending, CurrentTeamID: 2, QueueEnteredAt: &otherPoolEnteredAt}
	for _, item := range []*models.Conversation{&first, &second, &otherPool} {
		if err := db.Create(item).Error; err != nil {
			t.Fatalf("create queued conversation: %v", err)
		}
	}

	firstSnapshot := services.ConversationQueueService.GetSnapshotAt(&first, now)
	secondSnapshot := services.ConversationQueueService.GetSnapshotAt(&second, now)
	otherSnapshot := services.ConversationQueueService.GetSnapshotAt(&otherPool, now)
	if firstSnapshot.Position != 1 || firstSnapshot.WaitingCount != 2 {
		t.Fatalf("unexpected first snapshot: %+v", firstSnapshot)
	}
	if secondSnapshot.Position != 2 || secondSnapshot.AheadCount != 1 {
		t.Fatalf("unexpected second snapshot: %+v", secondSnapshot)
	}
	if otherSnapshot.Position != 1 || otherSnapshot.WaitingCount != 1 {
		t.Fatalf("unexpected other-pool snapshot: %+v", otherSnapshot)
	}
}

func TestConversationPureHumanGlobalQueueDispatchesFIFOAndHonorsCapacity(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	createHumanDispatchTeam(t, db, 1, "售后支持组")
	createHumanDispatchActiveSchedule(t, db, 1)
	createHumanDispatchAgentProfile(t, db, 101, 1, enums.ServiceStatusIdle, 1, true, enums.StatusOk)
	now := time.Now()
	olderEnteredAt := now.Add(-2 * time.Minute)
	newerEnteredAt := now.Add(-time.Minute)
	older := createHumanDispatchConversation(t, db, 0, enums.IMConversationStatusPending)
	newer := createHumanDispatchConversation(t, db, 0, enums.IMConversationStatusPending)
	if err := db.Model(&models.Conversation{}).Where("id = ?", older.ID).Update("queue_entered_at", olderEnteredAt).Error; err != nil {
		t.Fatalf("set older queue time: %v", err)
	}
	if err := db.Model(&models.Conversation{}).Where("id = ?", newer.ID).Update("queue_entered_at", newerEnteredAt).Error; err != nil {
		t.Fatalf("set newer queue time: %v", err)
	}

	count, err := services.ConversationDispatchService.DispatchPendingConversations(10)
	if err != nil {
		t.Fatalf("DispatchPendingConversations() error = %v", err)
	}
	if count != 1 {
		t.Fatalf("expected one dispatch at capacity, got %d", count)
	}
	olderCurrent := services.ConversationService.Get(older.ID)
	newerCurrent := services.ConversationService.Get(newer.ID)
	if olderCurrent.Status != enums.IMConversationStatusActive || olderCurrent.CurrentAssigneeID != 101 {
		t.Fatalf("expected oldest conversation assigned first, got %+v", olderCurrent)
	}
	if newerCurrent.Status != enums.IMConversationStatusPending || newerCurrent.CurrentAssigneeID != 0 {
		t.Fatalf("expected newer conversation to remain queued, got %+v", newerCurrent)
	}
}

func TestConversationConcurrentAutoDispatchCreatesSingleAssignment(t *testing.T) {
	db := setupConversationHumanDispatchTestDB(t)
	createHumanDispatchTeam(t, db, 1, "售后支持组")
	createHumanDispatchActiveSchedule(t, db, 1)
	createHumanDispatchAgentProfile(t, db, 101, 1, enums.ServiceStatusIdle, 3, true, enums.StatusOk)
	conversation := createHumanDispatchConversation(t, db, 0, enums.IMConversationStatusPending)
	now := time.Now()
	if err := db.Model(&models.Conversation{}).Where("id = ?", conversation.ID).Update("queue_entered_at", now).Error; err != nil {
		t.Fatalf("set queue time: %v", err)
	}

	var waitGroup sync.WaitGroup
	for range 8 {
		waitGroup.Add(1)
		go func() {
			defer waitGroup.Done()
			_, _ = services.ConversationDispatchService.DispatchConversation(conversation.ID)
		}()
	}
	waitGroup.Wait()

	var assignmentCount int64
	if err := db.Model(&models.ConversationAssignment{}).Where("conversation_id = ?", conversation.ID).Count(&assignmentCount).Error; err != nil {
		t.Fatalf("count assignments: %v", err)
	}
	if assignmentCount != 1 {
		t.Fatalf("expected exactly one assignment, got %d", assignmentCount)
	}
}

func setupConversationHumanDispatchTestDB(t *testing.T) *gorm.DB {
	t.Helper()
	dbName := strings.NewReplacer("/", "_", " ", "_").Replace(t.Name())
	db, err := gorm.Open(sqlite.Open("file:"+dbName+"?mode=memory&cache=shared"), &gorm.Config{
		NamingStrategy: schema.NamingStrategy{
			TablePrefix:   "t_",
			SingularTable: true,
		},
	})
	if err != nil {
		t.Fatalf("open sqlite error = %v", err)
	}
	t.Cleanup(func() {
		sqlDB, err := db.DB()
		if err == nil {
			_ = sqlDB.Close()
		}
	})
	if err := db.AutoMigrate(
		&models.AIAgent{},
		&models.AgentTeam{},
		&models.AgentTeamSchedule{},
		&models.AgentProfile{},
		&models.Conversation{},
		&models.ConversationParticipant{},
		&models.ConversationAssignment{},
		&models.ConversationEventLog{},
		&models.ConversationReadState{},
		&models.Message{},
		&models.ChannelMessageOutbox{},
	); err != nil {
		t.Fatalf("auto migrate error = %v", err)
	}
	sqls.SetDB(db)
	return db
}

func createHumanDispatchAIAgent(t *testing.T, db *gorm.DB, mode enums.IMConversationServiceMode, teamIDs string) models.AIAgent {
	t.Helper()
	item := models.AIAgent{
		Name:        "测试AI",
		ServiceMode: mode,
		TeamIDs:     teamIDs,
		Status:      enums.StatusOk,
	}
	if err := db.Create(&item).Error; err != nil {
		t.Fatalf("create ai agent error = %v", err)
	}
	return item
}

func createHumanDispatchTeam(t *testing.T, db *gorm.DB, id int64, name string) {
	t.Helper()
	if err := db.Create(&models.AgentTeam{ID: id, Name: name, Status: enums.StatusOk}).Error; err != nil {
		t.Fatalf("create team error = %v", err)
	}
}

func createHumanDispatchActiveSchedule(t *testing.T, db *gorm.DB, teamID int64) {
	t.Helper()
	now := time.Now()
	if err := db.Create(&models.AgentTeamSchedule{
		TeamID:  teamID,
		StartAt: now.Add(-time.Hour),
		EndAt:   now.Add(time.Hour),
		Status:  enums.StatusOk,
	}).Error; err != nil {
		t.Fatalf("create schedule error = %v", err)
	}
}

func createHumanDispatchAgentProfile(t *testing.T, db *gorm.DB, userID, teamID int64, serviceStatus enums.ServiceStatus, maxConcurrent int, autoAssign bool, status enums.Status) {
	t.Helper()
	registerTestExternalSubject(userID, "agent", "客服", enums.StatusOk)
	if err := db.Create(&models.AgentProfile{
		UserID:             userID,
		TeamID:             teamID,
		AgentCode:          "A001",
		DisplayName:        "客服",
		ServiceStatus:      serviceStatus,
		MaxConcurrentCount: maxConcurrent,
		AutoAssignEnabled:  autoAssign,
		Status:             status,
	}).Error; err != nil {
		t.Fatalf("create profile error = %v", err)
	}
}

func createHumanDispatchConversation(t *testing.T, db *gorm.DB, aiAgentID int64, status enums.IMConversationStatus) models.Conversation {
	t.Helper()
	now := time.Now()
	item := models.Conversation{
		AIAgentID:     aiAgentID,
		ChannelID:     1,
		CustomerID:    1,
		CustomerName:  "测试访客",
		Status:        status,
		ServiceMode:   enums.IMConversationServiceModeAIFirst,
		LastMessageAt: now,
		LastActiveAt:  now,
	}
	if err := db.Create(&item).Error; err != nil {
		t.Fatalf("create conversation error = %v", err)
	}
	return item
}

func testHumanDispatchOperator() *dto.AuthPrincipal {
	return &dto.AuthPrincipal{UserID: 9, Username: "dispatcher", Nickname: "调度员"}
}