package repository

import (
	"x-agents/server/internal/model"

	"gorm.io/gorm"
)

type ChatRepository struct {
	db *gorm.DB
}

func NewChatRepository(db *gorm.DB) *ChatRepository {
	return &ChatRepository{db: db}
}

// Session CRUD

// CreateSession 创建会话
func (r *ChatRepository) CreateSession(session *model.ChatSession) error {
	return r.db.Create(session).Error
}

// GetSessionByID 根据ID获取会话
func (r *ChatRepository) GetSessionByID(id string) (*model.ChatSession, error) {
	var session model.ChatSession
	err := r.db.Where("id = ?", id).First(&session).Error
	if err != nil {
		return nil, err
	}
	return &session, nil
}

// GetSessionsByUserID 获取用户的所有会话
func (r *ChatRepository) GetSessionsByUserID(userID string, limit, offset int) ([]model.ChatSession, int64, error) {
	var sessions []model.ChatSession
	var total int64

	query := r.db.Model(&model.ChatSession{}).Where("user_id = ?", userID)
	query.Count(&total)

	err := query.Order("updated_at DESC").Limit(limit).Offset(offset).Find(&sessions).Error
	return sessions, total, err
}

// UpdateSession 更新会话
func (r *ChatRepository) UpdateSession(session *model.ChatSession) error {
	return r.db.Save(session).Error
}

// DeleteSession 删除会话
func (r *ChatRepository) DeleteSession(id string) error {
	// 先删除会话下的所有消息
	r.db.Where("session_id = ?", id).Delete(&model.ChatMessage{})
	// 再删除会话
	return r.db.Delete(&model.ChatSession{}, "id = ?", id).Error
}

// Message CRUD

// CreateMessage 创建消息
func (r *ChatRepository) CreateMessage(message *model.ChatMessage) error {
	return r.db.Create(message).Error
}

// GetMessagesBySessionID 获取会话的所有消息
func (r *ChatRepository) GetMessagesBySessionID(sessionID string, limit, offset int) ([]model.ChatMessage, int64, error) {
	var messages []model.ChatMessage
	var total int64

	query := r.db.Model(&model.ChatMessage{}).Where("session_id = ?", sessionID)
	query.Count(&total)

	err := query.Order("created_at ASC").Limit(limit).Offset(offset).Find(&messages).Error
	return messages, total, err
}

// DeleteMessage 删除消息
func (r *ChatRepository) DeleteMessage(id string) error {
	return r.db.Delete(&model.ChatMessage{}, "id = ?", id).Error
}

// DeleteMessagesBySessionID 删除会话的所有消息
func (r *ChatRepository) DeleteMessagesBySessionID(sessionID string) error {
	return r.db.Where("session_id = ?", sessionID).Delete(&model.ChatMessage{}).Error
}