package model

import (
	"context"
	"fmt"
	"git.noahlan.cn/northlan/ntools-go/gorm-zero/gormc"
	"github.com/pkg/errors"
	"gorm.io/gorm"
	"live-service/common/nerr"
)

var _ UserIntegralModel = (*customUserIntegralModel)(nil)

type (
	// UserIntegralModel is an interface to be customized, add more methods here,
	// and implement the added methods in customUserIntegralModel.
	UserIntegralModel interface {
		userIntegralModel
		Transact(ctx context.Context, tx *gorm.DB, fn func(tx *gorm.DB) error) error
		InsertTx(ctx context.Context, tx *gorm.DB, data *UserIntegral) error
		UpdateIntegralTx(ctx context.Context, tx *gorm.DB, userId, addon int64) error
		FindIntegral(ctx context.Context, tx *gorm.DB, userId int64) (int64, error)
		// ChangeIntegral 用户积分变动
		ChangeIntegral(ctx context.Context, tx *gorm.DB, userId int64, change int64) (int64, error)
	}

	customUserIntegralModel struct {
		*defaultUserIntegralModel
	}
)

// NewUserIntegralModel returns a model for the database table.
func NewUserIntegralModel(conn *gorm.DB) UserIntegralModel {
	return &customUserIntegralModel{
		defaultUserIntegralModel: newUserIntegralModel(conn),
	}
}

func (m *customUserIntegralModel) Transact(ctx context.Context, tx *gorm.DB, fn func(tx *gorm.DB) error) error {
	return withTx(ctx, m.conn, tx).Transaction(fn)
}

func (m *customUserIntegralModel) InsertTx(ctx context.Context, tx *gorm.DB, data *UserIntegral) error {
	err := withTx(ctx, m.conn, tx).Create(&data).Error
	return err
}

func (m *customUserIntegralModel) UpdateIntegralTx(ctx context.Context, tx *gorm.DB, userId, change int64) error {
	if change < 0 {
		return errors.New("无法将积分更新至负数")
	}
	db := withTx(ctx, m.conn, tx)

	result := db.Table(m.table).
		Where("user_id = ?", userId).
		Update("integral", change)
	if result.Error != nil {
		return result.Error
	}
	if result.RowsAffected == 0 {
		return ErrRowsAffectedZero
	}
	return nil
}

func (m *customUserIntegralModel) FindIntegral(ctx context.Context, tx *gorm.DB, userId int64) (int64, error) {
	var resp int64
	err := withTx(ctx, m.conn, tx).Table(m.table).
		Select(fmt.Sprintf("%s.integral", m.table)).
		Where("user_id = ?", userId).Take(&resp).Error
	switch err {
	case nil:
		return resp, nil
	case gormc.ErrNotFound:
		return 0, ErrNotFound
	default:
		return 0, err
	}
}

func (m *customUserIntegralModel) ChangeIntegral(ctx context.Context, tx *gorm.DB, userId int64, change int64) (int64, error) {
	resp := change
	err := withTx(ctx, m.conn, tx).Transaction(func(tx *gorm.DB) error {
		integral, err := m.FindIntegral(ctx, tx, userId)
		if err != nil {
			if errors.Is(err, ErrNotFound) {
				if change < 0 {
					return nerr.NewWithCode(nerr.UserIntegralNotEnoughError)
				}
				// 用户积分记录不存在,进行插入
				if err = m.InsertTx(ctx, tx, &UserIntegral{
					UserId:   userId,
					Integral: change,
				}); err != nil {
					return errors.Wrap(err, "插入用户积分失败")
				}
				return nil
			} else {
				return errors.Wrap(err, "获取当前用户积分失败")
			}
		}
		if integral+change < 0 {
			return errors.New("用户积分不足")
		}
		if err = m.UpdateIntegralTx(ctx, tx, userId, integral+change); err != nil {
			return errors.Wrap(err, "更新用户积分失败")
		}
		resp = integral + change
		return nil
	})
	return resp, err
}