package services

import (
	"context"
	"encoding/json"
	"fmt"
	"platform/pkg/rds"
	"platform/web/common"
	m "platform/web/models"
	q "platform/web/queries"
	"strings"
	"time"

	"github.com/gofiber/fiber/v2"
)

var Resource = &resourceService{}

type resourceService struct{}

func (s *resourceService) PrepareResource(ctx context.Context, data *CreateResourceData, uid int32, tradeNo string, method int32) error {
	amount := data.GetPrice()

	// 保存到数据库
	err := q.Q.Transaction(func(q *q.Query) error {
		// 创建交易订单
		var trade = m.Trade{
			UserID:  uid,
			InnerNo: tradeNo,
			Subject: "购买套餐 - " + data.GetName(),
			Method:  method,
			Type:    1,
			Status:  0,
			Amount:  amount,
		}
		err := q.Trade.Create(&trade)
		if err != nil {
			return err
		}

		// 保存用户帐单
		bill := m.Bill{
			UserID:  uid,
			TradeID: trade.ID,
			BillNo:  ID.GenReadable("bil"),
			Info:    "购买套餐 - " + data.GetName(),
			Type:    1,
			Amount:  -amount,
		}
		err = q.Bill.
			Omit(q.Bill.ResourceID, q.Bill.RefundID).
			Create(&bill)
		if err != nil {
			return err
		}

		// 保存请求缓存
		cache := &CreateResourceCache{
			CreateResourceData: *data,
			Uid:                uid,
			TradeId:            trade.ID,
			BillId:             bill.ID,
		}

		reqStr, err := json.Marshal(cache)
		if err != nil {
			return err
		}

		err = rds.Client.Set(ctx, tradeNo, reqStr, 30*time.Minute).Err()
		if err != nil {
			return err
		}

		return nil
	})
	if err != nil {
		return err
	}

	return nil
}

func (s *resourceService) CreateResourcePrepared(ctx context.Context, tradeNo string, outerTradeNo string, payment float64, at time.Time) error {

	// 获取请求缓存
	reqStr, err := rds.Client.Get(ctx, tradeNo).Result()
	if err != nil {
		return err
	}

	cache := new(CreateResourceCache)
	if err := json.Unmarshal([]byte(reqStr), cache); err != nil {
		return err
	}

	// 保存交易信息
	err = q.Q.Transaction(func(q *q.Query) error {

		// 保存套餐
		resource, err := createResource(&cache.CreateResourceData, cache.Uid)
		if err != nil {
			return err
		}

		// 更新订单状态
		_, err = q.Trade.Debug().
			Select(q.Trade.OuterNo, q.Trade.Payment, q.Trade.Status, q.Trade.PaidAt).
			Updates(&m.Trade{
				ID:      cache.TradeId,
				OuterNo: outerTradeNo,
				Payment: payment,
				Status:  1,
				PaidAt:  common.LocalDateTime(at),
			})
		if err != nil {
			return err
		}

		// 更新账单状态
		_, err = q.Bill.Debug().
			Select(q.Bill.ResourceID).
			Updates(&m.Bill{
				ID:         cache.BillId,
				ResourceID: resource.ID,
			})
		if err != nil {
			return err
		}

		// 删除缓存
		err = rds.Client.Del(ctx, tradeNo).Err()
		if err != nil {
			return err
		}

		return nil
	})
	if err != nil {
		return err
	}

	return nil
}

func (s *resourceService) CreateResourceImmediately(data *CreateResourceData, uid int32) error {

	// 保存交易信息
	err := q.Q.Transaction(func(q *q.Query) error {

		// 保存套餐
		resource, err := createResource(data, uid)
		if err != nil {
			return err
		}

		// 生成账单
		bill := m.Bill{
			UserID:     uid,
			ResourceID: resource.ID,
			BillNo:     ID.GenReadable("bil"),
			Info:       "购买套餐 - " + data.GetName(),
			Type:       1,
			Amount:     data.GetPrice(),
		}
		err = q.Bill.
			Omit(q.Bill.TradeID, q.Bill.RefundID).
			Create(&bill)
		if err != nil {
			return err
		}

		return nil
	})
	if err != nil {
		return err
	}

	return nil
}

type CreateResourceData struct {
	Type       int32 `json:"type" validate:"required"`
	Live       int32 `json:"live" validate:"required"`
	Expire     int32 `json:"expire" validate:"required"`
	Quota      int32 `json:"quota" validate:"required"`
	DailyLimit int32 `json:"daily_limit" validate:"required"`

	name  string
	price float64
}

func (data *CreateResourceData) GetName() string {
	if data.name == "" {
		sb := strings.Builder{}
		sb.WriteString("短效动态")
		switch data.Type {
		case 1:
			sb.WriteString("包时 ")
		case 2:
			sb.WriteString("包量 ")
		}
		sb.WriteString(fmt.Sprintf("%d 分钟", data.Live/60))
		data.name = sb.String()
	}
	return data.name
}

func (data *CreateResourceData) GetPrice() float64 {
	if data.price == 0 {
		data.price = 0.01
	}
	return data.price
}

type CreateResourceCache struct {
	CreateResourceData `json:"data"`
	Uid                int32 `json:"uid"`
	TradeId            int32 `json:"trade_id"`
	BillId             int32 `json:"bill_id"`
}

func createResource(data *CreateResourceData, uid int32) (*m.Resource, error) {
	amount := data.GetPrice()

	// 检查用户
	user, err := q.User.
		Where(
			q.User.ID.Eq(uid),
			q.User.Status.Eq(1),
		).
		Take()
	if err != nil {
		return nil, err
	}

	// 检查余额
	if user.Balance < amount {
		return nil, fiber.NewError(fiber.StatusBadRequest, "余额不足")
	}

	// 创建套餐
	resource := &m.Resource{
		UserID:     user.ID,
		ResourceNo: ID.GenReadable("res"),
		Active:     true,
		Type:       1,
		Pss: &m.ResourcePss{
			Type:       data.Type,
			Live:       data.Live,
			Quota:      data.Quota,
			Expire:     common.LocalDateTime(time.Now().Add(time.Duration(data.Expire) * time.Second)),
			DailyLimit: data.DailyLimit,
		},
	}
	err = q.Resource.Create(resource)
	if err != nil {
		return nil, err
	}

	// 更新用户余额
	user.Balance -= amount
	_, err = q.User.
		Where(q.User.ID.Eq(uid)).
		Update(q.User.Balance, user.Balance)
	if err != nil {
		return nil, err
	}

	return resource, nil
}

func (s *resourceService) CancelResource(ctx context.Context, tradeNo string, at time.Time) error {
	// 获取请求缓存
	_, err := rds.Client.Del(ctx, tradeNo).Result()
	if err != nil {
		return err
	}

	// 更新订单状态
	_, err = q.Trade.
		Where(q.Trade.InnerNo.Eq(tradeNo)).
		Select(q.Trade.Status, q.Trade.CancelAt).
		Updates(m.Trade{
			Status:   2,
			CancelAt: common.LocalDateTime(at),
		})
	if err != nil {
		return err
	}

	return nil
}