package common

type PageParams struct {
	Page  int  `json:"page"`
	Num   int  `json:"pageSize"`
	Total int  `json:"total"`
	Last  bool `json:"last"`
}

//从0开始的分页
func (this *PageParams) GetPageParams() (pageNum int, start int) {
	start = this.Page * this.Num
	if this.Total <= this.Num {
		this.Page = 0
		this.Last = true
		return this.Total, 0
	}
	_start := (this.Page + 1) * this.Num

	if this.Total-_start < 0 {
		this.Last = true
		pageCount := this.Total / this.Num
		this.Page = pageCount
		num := this.Total - pageCount*this.Num
		if num == 0 {
			pageCount = pageCount - 1
			return this.Num, pageCount * this.Num
		}
		return num, pageCount * this.Num
	} else if this.Total-_start == 0 {
		this.Last = true
	}
	return this.Num, start
}