62 lines
962 B
Go
62 lines
962 B
Go
package controller
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import (
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"math"
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"strconv"
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"github.com/labstack/echo/v4"
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)
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const (
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// DefaultItemsPerPage stores the default amount of items per page
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DefaultItemsPerPage = 20
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)
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type Pager struct {
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Items int
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Page int
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ItemsPerPage int
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Pages int
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}
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func NewPager(c echo.Context) Pager {
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p := Pager{
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ItemsPerPage: DefaultItemsPerPage,
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Page: 1,
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}
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if page := c.QueryParam("page"); page != "" {
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if pageInt, err := strconv.Atoi(page); err != nil {
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if pageInt > 0 {
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p.Page = pageInt
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}
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}
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}
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return p
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}
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func (p *Pager) SetItems(items int) {
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p.Items = items
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p.Pages = int(math.Ceil(float64(items) / float64(p.ItemsPerPage)))
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if p.Page > p.Pages {
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p.Page = p.Pages
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}
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}
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func (p *Pager) IsBeginning() bool {
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return p.Page == 1
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}
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func (p *Pager) IsEnd() bool {
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return p.Page >= p.Pages
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}
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func (p *Pager) GetOffset() int {
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if p.Page == 0 {
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p.Page = 1
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}
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return (p.Page - 1) * p.ItemsPerPage
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}
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