package stocks

import (
	"context"
	"joybuywork/internal/repository/dao"
	"joybuywork/internal/service/provider/cachecurd"
	"joybuywork/internal/utils/logic"
	"joybuywork/internal/utils/merr"
	"strconv"
)

type IStock interface {
	Key(id int64) string                          // 缓存key
	BuildStock(id int64) (*cachecurd.HMap, error) // 构建库存缓存
}

type stocks struct {
	logic.Context
	ids      []int64
	stockMap map[int64]*cachecurd.HMap

	im IStock
}

func (s *stocks) Init(ctx context.Context, im IStock, ids []int64) (err error) {
	s.Context.Init(ctx, dao.Q, merr.NewBE(ctx))
	s.ids = ids
	s.stockMap = make(map[int64]*cachecurd.HMap, len(ids))
	s.im = im
	for _, id := range ids {
		s.stockMap[id], err = im.BuildStock(id)
		if err != nil {
			return
		}
	}

	return
}

// Total 奖品总库存
func (s *stocks) Total(id int64) (num int64, err error) {
	return s.getField(id, cachecurd.StockFieldStock)
}

// GetUseStock 获取奖品已使用库存数量
func (s *stocks) GetUseStock(id int64) (num int64, err error) {
	return s.getField(id, cachecurd.StockFieldUseStock)
}

// AddUseStock 添加库存使用量
func (s *stocks) AddUseStock(total int64, ids ...int64) (err error) {
	if len(ids) == 0 {
		ids = s.ids
	}

	for _, id := range ids {
		stock, ok := s.stockMap[id]
		if !ok {
			continue
		}
		_, err = stock.Incr(cachecurd.StockFieldUseStock, total)
		if err != nil {
			return
		}
	}

	return
}

// AllUseStock 奖品集合已使用库存数量
func (s *stocks) AllUseStock(ids ...int64) (data map[int64]int64, err error) {
	if len(ids) == 0 {
		ids = s.ids
	}

	data = make(map[int64]int64, len(ids))
	for _, id := range ids {
		data[id], err = s.GetUseStock(id)
		if err != nil {
			return
		}
	}

	return
}

// ClearUseStock 清空缓存
func (s *stocks) ClearUseStock(ids ...int64) (err error) {
	clearIds := s.ids
	if len(ids) > 0 {
		clearIds = ids
	}

	for _, id := range clearIds {
		stock, ok := s.stockMap[id]
		if !ok {
			continue
		}
		err = stock.Clear()
		if err != nil {
			return
		}
	}

	return
}

// DecrPoolAndAdd 扣除奖品池成功增加库存使用
func (s *stocks) DecrPoolAndAdd(id, val int64) (ok bool, err error) {
	stock, err := s.getAndSet(id)
	if err != nil {
		return
	}
	num, err := stock.Incr(cachecurd.StockFieldPoolNum, -val)
	if err != nil {
		return
	}
	if num < 0 {
		return
	}

	err = s.AddUseStock(val, id)
	if err != nil {
		return
	}

	return true, nil
}

// 获取缓存，没有就设置
func (s *stocks) getAndSet(id int64) (stock *cachecurd.HMap, err error) {
	stock, ok := s.stockMap[id]
	if ok {
		return
	}

	stock, err = s.im.BuildStock(id)
	if err != nil {
		return
	}

	s.stockMap[id] = stock
	s.ids = append(s.ids, id)

	return
}

// 获取库存缓存的某个字段
func (s *stocks) getField(id int64, field string) (total int64, err error) {
	stock, err := s.getAndSet(id)
	if err != nil {
		return
	}

	val, err := stock.Get(field)
	if err != nil {
		return
	}

	return strconv.ParseInt(val, 10, 64)
}