2021-12-18 13:55:35 -08:00
|
|
|
package controller
|
2021-12-03 04:20:01 -08:00
|
|
|
|
|
|
|
import (
|
|
|
|
"math"
|
|
|
|
"strconv"
|
|
|
|
|
|
|
|
"github.com/labstack/echo/v4"
|
|
|
|
)
|
|
|
|
|
2021-12-18 13:55:35 -08:00
|
|
|
const (
|
|
|
|
// DefaultItemsPerPage stores the default amount of items per page
|
|
|
|
DefaultItemsPerPage = 20
|
|
|
|
)
|
|
|
|
|
2021-12-03 04:20:01 -08:00
|
|
|
type Pager struct {
|
|
|
|
Items int
|
|
|
|
Page int
|
|
|
|
ItemsPerPage int
|
|
|
|
Pages int
|
|
|
|
}
|
|
|
|
|
2021-12-18 13:55:35 -08:00
|
|
|
func NewPager(c echo.Context) Pager {
|
2021-12-03 04:20:01 -08:00
|
|
|
p := Pager{
|
2021-12-18 13:55:35 -08:00
|
|
|
ItemsPerPage: DefaultItemsPerPage,
|
2021-12-03 04:20:01 -08:00
|
|
|
Page: 1,
|
|
|
|
}
|
|
|
|
|
|
|
|
if page := c.QueryParam("page"); page != "" {
|
|
|
|
if pageInt, err := strconv.Atoi(page); err != nil {
|
|
|
|
if pageInt > 0 {
|
|
|
|
p.Page = pageInt
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return p
|
|
|
|
}
|
|
|
|
|
|
|
|
func (p *Pager) SetItems(items int) {
|
|
|
|
p.Items = items
|
|
|
|
p.Pages = int(math.Ceil(float64(items) / float64(p.ItemsPerPage)))
|
|
|
|
|
|
|
|
if p.Page > p.Pages {
|
|
|
|
p.Page = p.Pages
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func (p *Pager) IsBeginning() bool {
|
|
|
|
return p.Page == 1
|
|
|
|
}
|
|
|
|
|
|
|
|
func (p *Pager) IsEnd() bool {
|
|
|
|
return p.Page >= p.Pages
|
|
|
|
}
|
|
|
|
|
|
|
|
func (p *Pager) GetOffset() int {
|
|
|
|
if p.Page == 0 {
|
|
|
|
p.Page = 1
|
|
|
|
}
|
|
|
|
return (p.Page - 1) * p.ItemsPerPage
|
|
|
|
}
|