// ===========================================
// 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 repository

import (
	"gorm.io/gorm"
	"gorm.io/gorm/clause"

	"hz-gitea.sea-studio.top/canglan/SharedClassManager/internal/model"
)

// ClassRepo 班级数据访问层
type ClassRepo struct {
	db *gorm.DB
}

// NewClassRepo 创建班级 Repository
func NewClassRepo(db *gorm.DB) *ClassRepo {
	return &ClassRepo{db: db}
}

// GetDB 获取底层数据库连接
func (r *ClassRepo) GetDB() *gorm.DB {
	return r.db
}

// GetByID 根据ID获取班级信息
func (r *ClassRepo) GetByID(classID int) (*model.Class, error) {
	var class model.Class
	if err := r.db.Where("class_id = ?", classID).First(&class).Error; err != nil {
		return nil, err
	}
	return &class, nil
}

// GetAll 获取所有班级列表
func (r *ClassRepo) GetAll(includeDisabled bool) ([]model.Class, error) {
	var classes []model.Class
	query := r.db.Where("1 = 1")
	if !includeDisabled {
		query = query.Where("status = 1")
	}
	if err := query.Order("class_id").Find(&classes).Error; err != nil {
		return nil, err
	}
	return classes, nil
}

// GetByName 根据班级名称获取班级
func (r *ClassRepo) GetByName(className string) (*model.Class, error) {
	var class model.Class
	if err := r.db.Where("class_name = ?", className).First(&class).Error; err != nil {
		return nil, err
	}
	return &class, nil
}

// Create 创建班级
func (r *ClassRepo) Create(class *model.Class) (int, error) {
	if err := r.db.Create(class).Error; err != nil {
		return 0, err
	}
	return class.ClassID, nil
}

// Update 更新班级信息（仅更新非零值字段）
func (r *ClassRepo) Update(classID int, updates map[string]interface{}) error {
	if len(updates) == 0 {
		return nil
	}
	return r.db.Model(&model.Class{}).
		Where("class_id = ?", classID).
		Updates(updates).Error
}

// Delete 删除班级（硬删除，需先确认无学生）
func (r *ClassRepo) Delete(classID int) error {
	return r.db.Where("class_id = ?", classID).Delete(&model.Class{}).Error
}

// GetStudentCount 获取班级活跃学生数量
func (r *ClassRepo) GetStudentCount(classID int) (int64, error) {
	var count int64
	if err := r.db.Model(&model.Student{}).
		Where("class_id = ? AND status = 1", classID).
		Count(&count).Error; err != nil {
		return 0, err
	}
	return count, nil
}

// HasActiveStudents 检查班级是否有活跃学生
func (r *ClassRepo) HasActiveStudents(classID int) (bool, error) {
	count, err := r.GetStudentCount(classID)
	if err != nil {
		return false, err
	}
	return count > 0, nil
}

// ========== 班级设置操作 ==========

// GetSettings 获取班级的所有设置
func (r *ClassRepo) GetSettings(classID int) ([]model.ClassSetting, error) {
	var settings []model.ClassSetting
	if err := r.db.Where("class_id = ?", classID).Find(&settings).Error; err != nil {
		return nil, err
	}
	return settings, nil
}

// GetSetting 获取班级单个设置项
func (r *ClassRepo) GetSetting(classID int, key string) (*model.ClassSetting, error) {
	var setting model.ClassSetting
	if err := r.db.Where("class_id = ? AND setting_key = ?", classID, key).First(&setting).Error; err != nil {
		return nil, err
	}
	return &setting, nil
}

// SaveSetting 保存班级设置项（upsert）
func (r *ClassRepo) SaveSetting(classID int, key, value string) error {
	setting := model.ClassSetting{
		ClassID:     classID,
		SettingKey:  key,
		SettingValue: value,
	}
	return r.db.Clauses(clause.OnConflict{
		Columns:   []clause.Column{{Name: "class_id"}, {Name: "setting_key"}},
		DoUpdates: clause.AssignmentColumns([]string{"setting_value"}),
	}).Create(&setting).Error
}

// BatchSaveSettings 批量保存班级设置项
func (r *ClassRepo) BatchSaveSettings(classID int, settings map[string]string) error {
	for key, value := range settings {
		if err := r.SaveSetting(classID, key, value); err != nil {
			return err
		}
	}
	return nil
}

// ========== 班级功能开关操作 ==========

// GetFeatures 获取班级的所有功能开关
func (r *ClassRepo) GetFeatures(classID int) ([]model.ClassFeature, error) {
	var features []model.ClassFeature
	if err := r.db.Where("class_id = ?", classID).Find(&features).Error; err != nil {
		return nil, err
	}
	return features, nil
}

// GetFeature 获取班级单个功能开关
func (r *ClassRepo) GetFeature(classID int, featureKey string) (*model.ClassFeature, error) {
	var feature model.ClassFeature
	if err := r.db.Where("class_id = ? AND feature_key = ?", classID, featureKey).First(&feature).Error; err != nil {
		return nil, err
	}
	return &feature, nil
}

// SaveFeature 保存班级功能开关（upsert）
func (r *ClassRepo) SaveFeature(classID int, featureKey string, enabled int8) error {
	feature := model.ClassFeature{
		ClassID:    classID,
		FeatureKey: featureKey,
		Enabled:    enabled,
	}
	return r.db.Clauses(clause.OnConflict{
		Columns:   []clause.Column{{Name: "class_id"}, {Name: "feature_key"}},
		DoUpdates: clause.AssignmentColumns([]string{"enabled"}),
	}).Create(&feature).Error
}