<?php

/**
 * DokuWiki Plugin Numbered Headings; action component
 *
 * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
 * @author     Satoshi Sahara <sahara.satoshi@gmail.com>
 */
class action_plugin_numberedheadings extends DokuWiki_Action_Plugin
{
    /**
     * Registers a callback function for a given event
     */
    public function register(Doku_Event_Handler $controller)
    {
        $controller->register_hook(
            'PARSER_HANDLER_DONE', 'BEFORE', $this, 'numbering', []
        );

        if ($this->getConf('fancy')) {
            $controller->register_hook(
                'RENDERER_CONTENT_POSTPROCESS', 'AFTER', $this, 'decorateTieredNumber'
            );
        }
    }

    /**
     * PARSER_HANDLER_DONE event handler
     * convert plugin instruction to header
     */
    public function numbering(Doku_Event $event)
    {
        // load helper object
        static $numbering;
        isset($numbering) || $numbering = $this->loadHelper($this->getPluginName());

        $instructions =& $event->data->calls;

        foreach ($instructions as $k => &$ins) {
            if ($ins[0] == 'plugin' && $ins[1][0] == 'numberedheadings') {
                // initialise variables to be extracted from data array
                // that was compacted in handle() process
                unset($dash, $level, $number, $title, $format);
                extract($ins[1][1]);

                if (!isset($dash)) { // not numbered headings
                    // set tier1 only
                    $numbering->setTier1($level);
                  //unset($instructions[$k]);
                    continue;
                }

                // auto-detect the first tier (Tier1) level
                $tier1 = $numbering->getTier1();
                if (!$tier1) {
                    $tier1 = $this->getConf('tier1') ?: $level;
                    $numbering->setTier1($tier1);
                }
                $tier = $level - $tier1 +1;

                // non-visible numbered headings, marked with '--'
                if ($dash > 1) {
                    // set the heading counter only if number seems meaningful
                    if ($number !== '') {
                        $numbering->setHeadingCounter($level, $number);
                    }

                    if (isset($format)) {
                        // set numbering format of current tier (and subtiers) in the page
                        $numbering->setTierFormat($format, $tier);

                    } elseif ($dash > 2 || $number === '' && $title === '' && $tier == 1) {
                        // reset numbering feature
                        // the first tier (Tier1) level should be decided in next match
                        $numbering->setTier1();
                        $numbering->setTierFormat();
                        $numbering->setHeadingCounter();
                    }
                  //unset($instructions[$k]);
                    continue;
                }

                // set the heading counter
                $numbering->setHeadingCounter($level, $number);

                // build tiered numbers for hierarchical headings
                $tieredNumbers = $numbering->getTieredNumbers($level);
                if ($tieredNumbers) {
                    // append double spaces after tiered number to distinguish title
                    $tieredNumbers .= $this->getConf('fancy') ? '  ' : ' ';
                }
                $text = $tieredNumbers.$title;

                // rewrite plugin call to header
                $ins[0] = 'header';
                $ins[1] = [$text, $level, $ins[2]];
            }
        }
        unset($ins);
        // reset numbering feature prior to process other pages
        $numbering->setTier1();
        $numbering->setTierFormat();
        $numbering->setHeadingCounter();
    }

    /**
     * RENDERER_CONTENT_POSTPROCESS
     * enclose tiered numbers of hierarchical headings in span tag
     */
    public function decorateTieredNumber(Doku_Event $event)
    {
        if ($event->data[0] == 'xhtml') {
            $search = '#(<h\d.*?>)(.+?)(  )(?=.*?</h\d>)#';
            $replacement = '${1}<span class="plugin_numberedheadings">${2}</span>'."\t";
            $event->data[1] = preg_replace($search, $replacement, $event->data[1]);
        }
    }

}