// ===========================================
// 多班级版班级管理系统 - Go 后端
//
// 开发者: Canglan
// 联系方式: admin@sea-studio.top
// 版权归属: Sea Network Technology Studio
// 许可证: Apache License 2.0
//
// 版权所有 © Sea Network Technology Studio
// ===========================================

package service

import (
	"context"
	"fmt"

	"hz-gitea.sea-studio.top/canglan/SharedClassManager/internal/config"
	"hz-gitea.sea-studio.top/canglan/SharedClassManager/internal/model"
	"hz-gitea.sea-studio.top/canglan/SharedClassManager/internal/repository"
	appJwt "hz-gitea.sea-studio.top/canglan/SharedClassManager/pkg/jwt"
	"hz-gitea.sea-studio.top/canglan/SharedClassManager/pkg/database"
)

// ClassService 班级服务
type ClassService struct {
	classRepo     *repository.ClassRepo
	userRepo      *repository.UserRepo
	adminRoleRepo *repository.AdminRoleRepo
}

// NewClassService 创建班级服务
func NewClassService(
	classRepo *repository.ClassRepo,
	userRepo *repository.UserRepo,
	adminRoleRepo *repository.AdminRoleRepo,
) *ClassService {
	return &ClassService{
		classRepo:     classRepo,
		userRepo:      userRepo,
		adminRoleRepo: adminRoleRepo,
	}
}

// ListClasses 获取班级列表
func (s *ClassService) ListClasses(includeDisabled bool) (map[string]interface{}, error) {
	classes, err := s.classRepo.GetAll(includeDisabled)
	if err != nil {
		return nil, err
	}

	for i := range classes {
		count, _ := s.classRepo.GetStudentCount(classes[i].ClassID)
		classes[i].StudentCount = count
	}

	return map[string]interface{}{
		"classes": classes,
		"total":   len(classes),
	}, nil
}

// GetClassDetail 获取班级详情
func (s *ClassService) GetClassDetail(classID int) (map[string]interface{}, error) {
	cls, err := s.classRepo.GetByID(classID)
	if err != nil {
		return nil, err
	}
	cls.StudentCount, _ = s.classRepo.GetStudentCount(classID)
	return map[string]interface{}{"class": cls}, nil
}

// CreateClass 创建班级
func (s *ClassService) CreateClass(className string, grade, description *string) (map[string]interface{}, error) {
	existing, _ := s.classRepo.GetByName(className)
	if existing != nil {
		return map[string]interface{}{"success": false, "message": "班级名称已存在"}, nil
	}

	cls := &model.Class{
		ClassName:   className,
		Grade:       grade,
		Description: description,
		Status:      1,
	}
	classID, err := s.classRepo.Create(cls)
	if err != nil {
		return nil, err
	}

	return map[string]interface{}{
		"success":  true,
		"class_id": classID,
		"message":  "班级创建成功",
	}, nil
}

// UpdateClass 更新班级
func (s *ClassService) UpdateClass(classID int, className, grade, description *string, status *int8) error {
	existing, err := s.classRepo.GetByID(classID)
	if err != nil {
		return fmt.Errorf("班级不存在")
	}

	updates := make(map[string]interface{})
	if className != nil && *className != existing.ClassName {
		nameExists, _ := s.classRepo.GetByName(*className)
		if nameExists != nil {
			return fmt.Errorf("班级名称已存在")
		}
		updates["class_name"] = *className
	}
	if grade != nil {
		updates["grade"] = *grade
	}
	if description != nil {
		updates["description"] = *description
	}
	if status != nil {
		updates["status"] = *status
	}

	return s.classRepo.Update(classID, updates)
}

// DeleteClass 删除班级
func (s *ClassService) DeleteClass(classID int) error {
	hasStudents, _ := s.classRepo.HasActiveStudents(classID)
	if hasStudents {
		return fmt.Errorf("该班级下还有学生，无法删除")
	}
	return s.classRepo.Delete(classID)
}

// SwitchClass 切换班级上下文（超级管理员）
func (s *ClassService) SwitchClass(userID int, classID int) (map[string]interface{}, error) {
	cfg := config.AppConfig
	cls, err := s.classRepo.GetByID(classID)
	if err != nil {
		return nil, fmt.Errorf("班级不存在")
	}

	user, err := s.userRepo.GetByUserID(userID)
	if err != nil {
		return nil, fmt.Errorf("用户不存在")
	}

	// 查询目标班级中该用户的角色
	var role string
	if user.UserType == "super_admin" {
		role = "系统管理员"
	} else {
		adminRole, _ := s.adminRoleRepo.GetByUserIDAndClass(userID, classID)
		if adminRole != nil {
			role = adminRole.RoleType
		}
	}

	// 生成新 Token，更新 class_id
	token, err := appJwt.CreateToken(
		user.UserID, user.Username, user.UserType,
		user.StudentID, role, user.RealName, &classID,
		user.NeedChangePassword == 1,
	)
	if err != nil {
		return nil, fmt.Errorf("生成令牌失败")
	}

	ctx := context.Background()
	_ = database.SetUserToken(ctx, userID, token, cfg.JWTIdleTimeoutMinutes)

	return map[string]interface{}{
		"token":      token,
		"class_id":   classID,
		"class_name": cls.ClassName,
	}, nil
}

// GetSettings 获取班级设置
func (s *ClassService) GetSettings(classID int) (map[string]interface{}, error) {
	settings, err := s.classRepo.GetSettings(classID)
	if err != nil {
		return nil, err
	}

	result := make(map[string]string)
	for _, setting := range settings {
		result[setting.SettingKey] = setting.SettingValue
	}
	return map[string]interface{}{"settings": result}, nil
}

// SaveSetting 保存班级设置
func (s *ClassService) SaveSetting(classID int, key, value string) error {
	return s.classRepo.SaveSetting(classID, key, value)
}

// GetFeatures 获取班级功能开关
func (s *ClassService) GetFeatures(classID int) (map[string]interface{}, error) {
	features, err := s.classRepo.GetFeatures(classID)
	if err != nil {
		return nil, err
	}

	result := make(map[string]int8)
	for _, f := range features {
		result[f.FeatureKey] = f.Enabled
	}
	return map[string]interface{}{"features": result}, nil
}

// SaveFeature 保存班级功能开关
func (s *ClassService) SaveFeature(classID int, featureKey string, enabled int8) error {
	return s.classRepo.SaveFeature(classID, featureKey, enabled)
}

// IsFeatureEnabled 检查功能开关是否启用
func (s *ClassService) IsFeatureEnabled(classID int, featureKey string) bool {
	feature, err := s.classRepo.GetFeature(classID, featureKey)
	if err != nil || feature == nil {
		return true // 默认启用
	}
	return feature.Enabled == 1
}