<?php

//include_once(dirname(dirname(__FILE__))."/publicBase.php");
class Page extends publicBase {
	public $totalnum;     // 总记录数[必填],例:$page->setTotalnum(100);
	public $page;         // 当前页码[必填]
	public $url;          // 分页URL[必填]
	public $pagesize=20;  // 每页记录数

	public $viewpagenum=7;   // 每页看到的页码数
	public $virtualpage='...';   // 省略或跨越页码

	public $totalpage;

	//mysql表中数据量过多时采用的分页改造
	public $first_page_url; //点击”首页“跳转链接
    public $end_page_url;   //点击”尾页“跳转链接
    public $prev_page_url; //点击”上一页“跳转链接
    public $next_page_url;   //点击”下一页“跳转链接
    public $endpage=false; //跳转到尾页标识
    public $jump_to_page_url; //跳转到某一页链接
    public $maxid; //点击上一页时 当前页面最大id
    public $minid; //点击下一页时 当前页面最小id


	/*
	 *  $pageobj = new Page();
    	$pageobj->setTotalnum($totalnum);
    	$pageobj->setPage($page);
    	$pageobj->setPagesize($pagesize);
    	$pageobj->setUrl('/comment/black/page/');
    	$plist = $pageobj->getPageList();
	 */

	/*
	listnum  显示页码数, 默认展示7页
	*/
	public function getPageList() {
		$pagelist = array();     // 构造的翻页数据
		$begin = $last = array();    // 开始,结尾数据

		$totalpage = ceil($this->totalnum/$this->pagesize);   // 总页数
		$this->totalpage = $totalpage;
		$middle_page = ceil($this->viewpagenum/2); // 每页中间页码值

		if($this->page > $middle_page && $totalpage > $this->viewpagenum)	{ // 开头有...时
		    $begin[] = array('page' => 1, 'url' => $this->url . '1');
		    $begin[] = array('page' => $this->virtualpage, 'url' => '');
		    $firstpage = $totalpage-$this->viewpagenum+2;
		    $endpage = $totalpage;

		    if($totalpage-$this->page > $middle_page) { // 结尾也有...时
		        $last[$totalpage-1] = array('page' => $this->virtualpage, 'url'=>'');
		        $last[$totalpage] = array('page' => $totalpage, 'url' => $this->url . $totalpage);
		        $firstpage = $this->page-$middle_page+2;
		        $endpage = $this->page+$middle_page-2;
		    }
		} elseif($totalpage-$this->page > $middle_page && $totalpage > $this->viewpagenum) {	// 只有结尾的...时
			$last[$totalpage-1] = array('page' => $this->virtualpage, 'url' => '');
			$last[$totalpage] = array('page' => $totalpage, 'url' => $this->url . $totalpage);

			$firstpage = 1;
			$endpage = $this->viewpagenum-1;
		} else {	// 没有...时
			$firstpage = 1;
			$endpage = $totalpage;
		}

		// 中间页码数据
		for ($i=$firstpage; $i<=$endpage; $i++)	{
			$pagelist[$i-1]['page'] = $i;
			$pagelist[$i-1]['url'] = $this->url . $i;
		}

        return $begin + $pagelist + $last;
	}

	public function getLimitInfo() {
	    $this->first_page_url = $this->url."/page/1";         //首页链接
	    $this->end_page_url = $this->url."/end_page/1"; //尾页链接
        $this->jump_to_page_url =  $this->url."/jump_to_page"; //跳转到某一页
        if($this->totalnum>0) $this->page = ceil($this->totalnum/$this->pagesize);
        if ($this->page > 1 || $this->endpage) $this->prev_page_url = $this->url.'/page/'.($this->page-1).'/maxid/'.$this->maxid; //上一页连接
        if (!$this->endpage) $this->next_page_url = $this->url.'/page/'.($this->page+1).'/minid/'.$this->minid; //下一页连接
	}
}