package menu

import (
	"context"
	"errors"
	"time"

	"git.x2erp.com/qdy/go-base/logger"
	"git.x2erp.com/qdy/go-db/factory/mongodb"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/primitive"
)

// SessionMenuMapping 会话-菜单映射结构
type SessionMenuMapping struct {
	ID         primitive.ObjectID `bson:"_id,omitempty" json:"id,omitempty"`
	SessionID  string             `bson:"session_id" json:"session_id"`     // 会话ID
	MenuItemID string             `bson:"menu_item_id" json:"menu_item_id"` // 菜单项ID
	UserID     string             `bson:"user_id" json:"user_id"`           // 用户ID
	TenantID   string             `bson:"tenant_id" json:"tenant_id"`       // 租户ID
	CreatedAt  time.Time          `bson:"created_at" json:"created_at"`     // 创建时间
}

// CollectionName 返回MongoDB集合名称
func (SessionMenuMapping) CollectionName() string {
	return "session_menu_mappings"
}

// MappingService 会话-菜单映射服务
type MappingService struct {
	mongoFactory *mongodb.MongoDBFactory
}

// NewMappingService 创建新的映射服务
func NewMappingService(factory *mongodb.MongoDBFactory) *MappingService {
	return &MappingService{mongoFactory: factory}
}

// CreateMapping 创建会话-菜单映射
func (s *MappingService) CreateMapping(ctx context.Context, sessionID, menuItemID, userID, tenantID string) error {
	mapping := SessionMenuMapping{
		SessionID:  sessionID,
		MenuItemID: menuItemID,
		UserID:     userID,
		TenantID:   tenantID,
		CreatedAt:  time.Now(),
	}

	_, success := s.mongoFactory.InsertOneWithResult(SessionMenuMapping{}.CollectionName(), mapping)
	if !success {
		logger.Error("创建会话-菜单映射失败", "session_id", sessionID, "menu_item_id", menuItemID)
		return errors.New("failed to create session-menu mapping")
	}

	logger.Debug("创建会话-菜单映射成功", "session_id", sessionID, "menu_item_id", menuItemID)
	return nil
}

// GetMenuItemBySessionID 根据会话ID获取菜单项ID
func (s *MappingService) GetMenuItemBySessionID(ctx context.Context, sessionID string) (string, error) {
	filter := bson.M{"session_id": sessionID}
	var mapping SessionMenuMapping

	err := s.mongoFactory.FindOne(SessionMenuMapping{}.CollectionName(), filter, &mapping)
	if err != nil {
		if err.Error() == "mongo: no documents in result" {
			return "", nil // 未找到映射，返回空字符串
		}
		logger.Error("根据会话ID查询菜单项失败", "session_id", sessionID, "error", err)
		return "", err
	}

	return mapping.MenuItemID, nil
}

// GetSessionIDsByMenuItemID 根据菜单项ID获取会话ID列表
func (s *MappingService) GetSessionIDsByMenuItemID(ctx context.Context, menuItemID, userID string) ([]string, error) {
	filter := bson.M{"menu_item_id": menuItemID, "user_id": userID}
	var mappings []SessionMenuMapping

	err := s.mongoFactory.Find(SessionMenuMapping{}.CollectionName(), filter, &mappings)
	if err != nil {
		logger.Error("根据菜单项ID查询会话ID失败", "menu_item_id", menuItemID, "error", err)
		return nil, err
	}

	sessionIDs := make([]string, 0, len(mappings))
	for _, mapping := range mappings {
		sessionIDs = append(sessionIDs, mapping.SessionID)
	}

	return sessionIDs, nil
}

// GetMappingsByUser 获取用户的所有会话-菜单映射
func (s *MappingService) GetMappingsByUser(ctx context.Context, userID string) (map[string]string, error) {
	filter := bson.M{"user_id": userID}
	var mappings []SessionMenuMapping

	err := s.mongoFactory.Find(SessionMenuMapping{}.CollectionName(), filter, &mappings)
	if err != nil {
		logger.Error("查询用户会话-菜单映射失败", "user_id", userID, "error", err)
		return nil, err
	}

	result := make(map[string]string)
	for _, mapping := range mappings {
		result[mapping.SessionID] = mapping.MenuItemID
	}

	return result, nil
}

// DeleteMappingBySessionID 根据会话ID删除映射
func (s *MappingService) DeleteMappingBySessionID(ctx context.Context, sessionID string) error {
	filter := bson.M{"session_id": sessionID}
	success, deletedCount := s.mongoFactory.DeleteOne(SessionMenuMapping{}.CollectionName(), filter)
	if !success {
		logger.Error("根据会话ID删除映射失败", "session_id", sessionID)
		return errors.New("failed to delete session-menu mapping")
	}

	logger.Debug("删除会话-菜单映射成功", "session_id", sessionID, "deleted_count", deletedCount)
	return nil
}

// EnsureIndexes 确保集合索引
func (s *MappingService) EnsureIndexes(ctx context.Context) error {
	// 创建会话ID唯一索引
	sessionIDIndexKeys := bson.D{{Key: "session_id", Value: 1}}
	sessionIDSuccess := s.mongoFactory.CreateIndex(SessionMenuMapping{}.CollectionName(), sessionIDIndexKeys)
	if !sessionIDSuccess {
		logger.Error("创建会话ID索引失败")
		return errors.New("failed to create session_id index")
	}

	// 创建复合索引：菜单项ID + 用户ID
	menuItemUserIndexKeys := bson.D{
		{Key: "menu_item_id", Value: 1},
		{Key: "user_id", Value: 1},
	}
	menuItemUserSuccess := s.mongoFactory.CreateIndex(SessionMenuMapping{}.CollectionName(), menuItemUserIndexKeys)
	if !menuItemUserSuccess {
		logger.Error("创建菜单项用户复合索引失败")
		return errors.New("failed to create menu_item_id-user_id index")
	}

	logger.Debug("会话-菜单映射索引创建成功")
	return nil
}