class PageInfo(object):
    def __init__(self, current_page, all_count, per_page, base_url, show_page):
        try:
            self.current_page = int(current_page)
        except Exception as e:
            self.current_page = 1
        self.per_page = per_page
        a, b = divmod(all_count, per_page)
        if b:
            a = a + 1
        self.all_pager = a
        self.show_page =show_page
        self.base_url =base_url
    def pager(self):
        page_list = []
        half = int((self.show_page-1)/2)
        # 如果資料總頁數<show_page
        if self.all_pager < self.show_page:
            begin = 1
            stop = self.all_pager + 1
        else:
            if self.current_page <= half:
                begin = 1
                stop = self.show_page + 1
            else:
                if self.current_page + half > self.all_pager:
                    begin = self.all_pager - self.show_page + 1
                    stop = self.all_pager + 1
                else:
                    begin = self.current_page - half
                    stop = self.current_page + half + 1
        if self.current_page <= 1:
            prev = '<li class="previous"><a>上一頁</a></li>'
        else:
            prev = '<li><a href="%s%s.html">上一頁</a></li>' % (self.base_url,self.current_page - 1)
        page_list.append(prev)

        for i in range(begin, stop):
            if i == self.current_page:
                temp = '<li class="active"><a href="%s%s.html">%s</a></li>' % (self.base_url,i, i)
            else:
                temp = '<li><a href="%s%s.html">%s</a></li>' % (self.base_url, i, i)

            page_list.append(temp)

        if self.current_page >= self.all_pager:
            nex = '<li><a>下一頁</a></li>'
        else:
            nex = '<li><a href="%s%s.html">下一頁</a></li>' % (self.base_url, self.current_page + 1)
        page_list.append(nex)

        return''.join(page_list)

    def start(self):
        return (self.current_page - 1) * self.per_page

    def end(self):
        return self.current_page * self.per_page