package service

import (
	"context"
	"math"
)

type Base struct {
}

type Page struct {
	Count       int64 `json:"total"`
	CurrentPage int   `json:"currentPage"`
	TotalPage   int   `json:"totalPage"`
	Start       int   `json:"start"`
	End         int   `json:"end"`
	PageSize    int   `json:"pageSize"`
	LimitStart  int   `json:"limitStart"`
}

func NewBase(ctx context.Context) *Base {
	return &Base{}
}

func (b *Base) InitPages(count int64, page, pageSize int) Page {
	var pages Page
	pages.Count = count
	page = int(math.Max(1, float64(page)))
	pages.CurrentPage = int(math.Min(float64(page), float64(count)))
	pages.TotalPage = int(math.Ceil(float64(count) / float64(pageSize)))
	pages.PageSize = pageSize
	pages.LimitStart = (pages.CurrentPage - 1) * pageSize
	return pages
}