<?php
/*
 * You may not change or alter any portion of this comment or credits
 * of supporting developers from this source code or any supporting source code
 * which is considered copyrighted (c) material of the original comment or credit authors.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 */

/**
 * @copyright    XOOPS Project https://xoops.org/
 * @license      GNU GPL 2 or later (http://www.gnu.org/licenses/gpl-2.0.html)
 * @package
 * @since
 * @author       XOOPS Development Team, Kazumi Ono (AKA onokazu)
 */

/**
 * Class to facilitate navigation in a multi page document/list
 *
 * @package              kernel
 * @subpackage           util
 *
 * @author               Kazumi Ono    <onokazu@xoops.org>
 * @copyright        (c) XOOPS Project (https://xoops.org)
 */

// defined('XOOPS_ROOT_PATH') || exit('Restricted access.');

/**
 * Class XoopsPageNav
 */
class XoopsPageNav
{
    /**#@+
     * @access    private
     */
    public $total;
    public $perpage;
    public $current;
    public $url;
    /**#@-*/

    /**
     * Constructor
     *
     * @param int    $total_items   Total number of items
     * @param int    $items_perpage Number of items per page
     * @param int    $current_start First item on the current page
     * @param string $start_name    Name for "start" or "offset"
     * @param string $extra_arg     Additional arguments to pass in the URL
     **/
    public function __construct($total_items, $items_perpage, $current_start, $start_name = 'start', $extra_arg = '')
    {
        $this->total   = (int)$total_items;
        $this->perpage = (int)$items_perpage;
        $this->current = (int)$current_start;
        if ('' !== $extra_arg && ('&amp;' !== substr($extra_arg, -5) || '&' !== substr($extra_arg, -1))) {
            $extra_arg .= '&amp;';
        }
        $this->url = $_SERVER['PHP_SELF'] . '?' . $extra_arg . trim($start_name) . '=';
    }

    /**
     * Create text navigation
     *
     * @param integer $offset
     *
     * @return string
     **/
    public function renderNav($offset = 4)
    {
        $ret = '';
        if ($this->total <= $this->perpage) {
            return $ret;
        }
        $total_pages = ceil($this->total / $this->perpage);
        if ($total_pages > 1) {
            $prev = $this->current - $this->perpage;
            if ($prev >= 0) {
                $ret .= '<a href="' . $this->url . $prev . '"><u>&laquo;</u></a> ';
            }
            $counter      = 1;
            $current_page = (int)floor(($this->current + $this->perpage) / $this->perpage);
            while ($counter <= $total_pages) {
                if ($counter == $current_page) {
                    $ret .= '<b>(' . $counter . ')</b> ';
                } elseif (($counter > $current_page - $offset && $counter < $current_page + $offset) || 1 == $counter
                          || $counter == $total_pages) {
                    if ($counter == $total_pages && $current_page < $total_pages - $offset) {
                        $ret .= '... ';
                    }
                    $ret .= '<a href="' . $this->url . (($counter - 1) * $this->perpage) . '">' . $counter . '</a> ';
                    if (1 == $counter && $current_page > 1 + $offset) {
                        $ret .= '... ';
                    }
                }
                ++$counter;
            }
            $next = $this->current + $this->perpage;
            if ($this->total > $next) {
                $ret .= '<a href="' . $this->url . $next . '"><u>&raquo;</u></a> ';
            }
        }

        return $ret;
    }

    /**
     * Create a navigational dropdown list
     *
     * @param boolean $showbutton Show the "Go" button?
     *
     * @return string
     **/
    public function renderSelect($showbutton = false)
    {
        if ($this->total < $this->perpage) {
            return null;
        }
        $total_pages = ceil($this->total / $this->perpage);
        $ret         = '';
        if ($total_pages > 1) {
            $ret          = '<form name="pagenavform">';
            $ret          .= '<select name="pagenavselect" onchange="location=this.options[this.options.selectedIndex].value;">';
            $counter      = 1;
            $current_page = (int)floor(($this->current + $this->perpage) / $this->perpage);
            while ($counter <= $total_pages) {
                if ($counter == $current_page) {
                    $ret .= '<option value="' . $this->url . (($counter - 1) * $this->perpage) . '" selected>' . $counter . '</option>';
                } else {
                    $ret .= '<option value="' . $this->url . (($counter - 1) * $this->perpage) . '">' . $counter . '</option>';
                }
                ++$counter;
            }
            $ret .= '</select>';
            if ($showbutton) {
                $ret .= '&nbsp;<input type="submit" value="' . _GO . '">';
            }
            $ret .= '</form>';
        }

        return $ret;
    }

    /**
     * Create an enhanced navigational dropdown list
     *
     * @param boolean $showbutton Show the "Go" button?
     * @param null    $titles
     *
     * @return string
     */
    public function renderEnhancedSelect($showbutton = false, $titles = null)
    {
        if ($this->total < $this->perpage) {
            return null;
        }
        $total_pages = ceil($this->total / $this->perpage);
        $ret         = '';
        if ($total_pages > 1) {
            $ret          = '<form name="pagenavform">';
            $ret          .= '<select name="pagenavselect" onchange="location=this.options[this.options.selectedIndex].value;">';
            $counter      = 1;
            $current_page = (int)floor(($this->current + $this->perpage) / $this->perpage);
            while ($counter <= $total_pages) {
                if (isset($titles[$counter - 1])) {
                    $title = $titles[$counter - 1];
                } else {
                    $title = $counter;
                }
                if ($counter == $current_page) {
                    $ret .= '<option value="' . $this->url . (($counter - 1) * $this->perpage) . '" selected>' . $title . '</option>';
                } else {
                    $ret .= '<option value="' . $this->url . (($counter - 1) * $this->perpage) . '">' . $title . '</option>';
                }
                ++$counter;
            }
            $ret .= '</select>';
            if ($showbutton) {
                $ret .= '&nbsp;<input type="submit" value="' . _GO . '">';
            }
            $ret .= '</form>';
        }

        return $ret;
    }

    /**
     * Create navigation with images
     *
     * @param integer $offset
     *
     * @return string
     **/
    public function renderImageNav($offset = 4)
    {
        if ($this->total < $this->perpage) {
            return null;
        }
        $total_pages = ceil($this->total / $this->perpage);
        $ret         = '';
        if ($total_pages > 1) {
            $ret  = '<table><tr>';
            $prev = $this->current - $this->perpage;
            if ($prev >= 0) {
                $ret .= '<td class="pagneutral"><a href="' . $this->url . $prev . '">&lt;</a></td><td><img src="' . XOOPS_URL . '/images/blank.gif" width="6" alt=""></td>';
            }
            $counter      = 1;
            $current_page = (int)floor(($this->current + $this->perpage) / $this->perpage);
            while ($counter <= $total_pages) {
                if ($counter == $current_page) {
                    $ret .= '<td class="pagact"><b>' . $counter . '</b></td>';
                } elseif (($counter > $current_page - $offset && $counter < $current_page + $offset) || 1 == $counter
                          || $counter == $total_pages) {
                    if ($counter == $total_pages && $current_page < $total_pages - $offset) {
                        $ret .= '<td class="paginact">...</td>';
                    }
                    $ret .= '<td class="paginact"><a href="' . $this->url . (($counter - 1) * $this->perpage) . '">' . $counter . '</a></td>';
                    if (1 == $counter && $current_page > 1 + $offset) {
                        $ret .= '<td class="paginact">...</td>';
                    }
                }
                ++$counter;
            }
            $next = $this->current + $this->perpage;
            if ($this->total > $next) {
                $ret .= '<td><img src="' . XOOPS_URL . '/images/blank.gif" width="6" alt=""></td><td class="pagneutral"><a href="' . $this->url . $next . '">></a></td>';
            }
            $ret .= '</tr></table>';
        }

        return $ret;
    }
}
