xref: /dokuwiki/inc/Ui/PageDiff.php (revision 48d75c0057e32072269dab43372c65184dcf6649)

<?php

namespace dokuwiki\Ui;

use dokuwiki\ChangeLog\PageChangeLog;
use dokuwiki\Form\Form;

/**
 * DokuWiki PageDiff Interface
 *
 * @package dokuwiki\Ui
 */
class PageDiff extends Diff
{
    /* @var string */
    protected $text = '';

    /**
     * PageDiff Ui constructor
     *
     * @param string $id  page id
     */
    public function __construct($id = null)
    {
        global $INFO;
        $this->id = isset($id) ? $id : $INFO['id'];

        // init preference
        $this->preference['showIntro'] = true;
        $this->preference['difftype'] = 'sidebyside'; // diff view type: inline or sidebyside

        $this->setChangeLog();
    }

    /** @inheritdoc */
    protected function setChangeLog()
    {
        $this->changelog = new PageChangeLog($this->id);
    }

    /**
     * Set text to be compared with most current version
     * exclusively use of the compare($old, $new) method
     *
     * @param string $text
     * @return $this
     */
    public function compareWith($text = null)
    {
        if (isset($text)) {
            $this->text = $text;
            $this->old_rev = '';
        }
        return $this;
    }

    /** @inheritdoc */
    protected function preProcess()
    {
        parent::preProcess();
        if (!isset($this->old_rev, $this->new_rev)) {
            // no revision was given, compare previous to current
            $this->old_rev = $this->changelog->getRevisions(0, 1)[0];
            $this->new_rev = '';

            global $INFO, $REV;
            if ($this->id == $INFO['id'])
               $REV = $this->old_rev; // store revision back in $REV
        }
    }

    /**
     * Show diff
     * between current page version and provided $text
     * or between the revisions provided via GET or POST
     *
     * @author Andreas Gohr <andi@splitbrain.org>
     *
     * @return void
     */
    public function show()
    {
        global $INFO;

       // determine left and right revision
        if (!isset($this->old_rev, $this->new_rev)) $this->preProcess();
        [$l_rev, $r_rev] = [$this->old_rev, $this->new_rev];

       // determine the last revision, which is usually the timestamp of current page,
       // however which might be the last revision if the page had removed.
       if ($this->id == $INFO['id']) {
           $this->last_rev = $INFO['currentrev'] ?? $INFO['meta']['last_change']['date'] ?? 0;
       } else {
           $this->last_rev = $this->changelog->getRevisions(-1, 1)[0] // empty array for removed page
                           ?: $this->changelog->getRevisions(0, 1)[0];
       }

       // build html diff view components
        list(
            $l_minor, $r_minor,
            $l_head,  $r_head,
            $l_text,  $r_text,
            $l_nav,   $r_nav,
        ) = $this->buildDiffViewComponents($l_rev, $r_rev);

        // create difference engine object
        $Difference = new \Diff(explode("\n", $l_text), explode("\n", $r_text));

        // display intro
        if ($this->preference['showIntro']) echo p_locale_xhtml('diff');

        // print form to choose diff view type, and exact url reference to the view
        if (!$this->text) {
            $this->showDiffViewSelector();
        }

        // display diff view table
        echo '<div class="table">';
        echo '<table class="diff diff_'.$this->preference['difftype'] .'">';

        //navigation and header
        switch ($this->preference['difftype']) {
            case 'inline':
                if (!$this->text) {
                    echo '<tr>'
                        .'<td class="diff-lineheader">-</td>'
                        .'<td class="diffnav">'. $l_nav .'</td>'
                        .'</tr>';
                    echo '<tr>'
                        .'<th class="diff-lineheader">-</th>'
                        .'<th '. $l_minor .'>'. $l_head .'</th>'
                        .'</tr>';
                }
                echo '<tr>'
                    .'<td class="diff-lineheader">+</td>'
                    .'<td class="diffnav">'. $r_nav .'</td>'
                    .'</tr>';
                echo '<tr>'
                    .'<th class="diff-lineheader">+</th>'
                    .'<th '. $r_minor .'>'. $r_head .'</th>'
                    .'</tr>';
                // create formatter object
                $DiffFormatter = new \InlineDiffFormatter();
                break;

            case 'sidebyside':
            default:
                if (!$this->text) {
                    echo '<tr>'
                        .'<td colspan="2" class="diffnav">'. $l_nav .'</td>'
                        .'<td colspan="2" class="diffnav">'. $r_nav .'</td>'
                        .'</tr>';
                }
                echo '<tr>'
                    .'<th colspan="2" '. $l_minor .'>'. $l_head .'</th>'
                    .'<th colspan="2" '. $r_minor .'>'. $r_head .'</th>'
                    .'</tr>';
                // create formatter object
                $DiffFormatter = new \TableDiffFormatter();
                break;
        }

        // output formatted difference
        echo $this->insertSoftbreaks($DiffFormatter->format($Difference));

        echo '</table>';
        echo '</div>';
    }

    /**
     * Print form to choose diff view type, and exact url reference to the view
     */
    protected function showDiffViewSelector()
    {
        global $INFO, $lang;

        echo '<div class="diffoptions group">';

        // create the form to select difftype
        $form = new Form(['action' => wl()]);
        $form->setHiddenField('id', $this->id);
        $form->setHiddenField('rev2[0]', $this->old_rev ?: 'current');
        $form->setHiddenField('rev2[1]', $this->new_rev ?: 'current');
        $form->setHiddenField('do', 'diff');
        $options = array(
                     'sidebyside' => $lang['diff_side'],
                     'inline' => $lang['diff_inline']
        );
        $input = $form->addDropdown('difftype', $options, $lang['diff_type'])
            ->val($this->preference['difftype'])
            ->addClass('quickselect');
        $input->useInput(false); // inhibit prefillInput() during toHTML() process
        $form->addButton('do[diff]', 'Go')->attr('type','submit');
        echo $form->toHTML();

        // show exact url reference to the view
        if ($this->id == $INFO['id']) {
            echo '<p>';
            // link to exactly this view FS#2835
            echo $this->diffViewlink('difflink', $this->old_rev, ($this->new_rev ?: $this->last_rev));
            echo '</p>';
        }

        echo '</div>'; // .diffoptions
    }

    /**
     * Build html diff view components
     *
     * @param int $l_rev  revision timestamp of left side
     * @param int $r_rev  revision timestamp of right side
     * @return array
     *       $l_minor, $r_minor,  // string  class attributes
     *       $l_head,  $r_head,   // string  html snippet
     *       $l_text,  $r_text,   // string  raw wiki text
     *       $l_nav,   $r_nav,    // string  html snippet
     */
    protected function buildDiffViewComponents($l_rev, $r_rev)
    {
        global $lang;

        if ($this->text) { // compare text to the most current revision
            $r_minor = '';
            $l_head = '<a class="wikilink1" href="'. wl($this->id) .'">'
                . $this->id .' '. dformat((int) @filemtime(wikiFN($this->id))) .'</a> '
                . $lang['current'];
            $l_text = rawWiki($this->id, '');

            $l_minor = '';
            $r_head = $lang['yours'];
            $r_text = cleanText($this->text);

        } else {
            // when both revisions are empty then the page was created just now
            if (!$l_rev && !$r_rev) {
                $l_text = '';
            } else {
                $l_text = rawWiki($this->id, $l_rev);
            }
            $r_text = rawWiki($this->id, $r_rev);

            // get header of diff HTML
            list(
                $l_head,  $r_head,
                $l_minor, $r_minor,
            ) = $this->buildDiffHead($l_rev, $r_rev);
        }
        // build navigation
        $l_nav = '';
        $r_nav = '';
        if (!$this->text) {
            list($l_nav, $r_nav) = $this->buildDiffNavigation($l_rev, $r_rev);
        }

        return array(
            $l_minor, $r_minor,
            $l_head,  $r_head,
            $l_text,  $r_text,
            $l_nav,   $r_nav,
        );
    }

    /**
     * Create html for revision navigation
     *
     * @param int           $l_rev   left revision timestamp
     * @param int           $r_rev   right revision timestamp
     * @return string[] html of left and right navigation elements
     */
    protected function buildDiffNavigation($l_rev, $r_rev)
    {
        global $INFO;

        // last timestamp is not in changelog, retrieve timestamp from metadata
        // note: when page is removed, the metadata timestamp is zero
        if (!$r_rev) {
            $r_rev = $this->last_rev;
        }

        //retrieve revisions with additional info
        list($l_revs, $r_revs) = $this->changelog->getRevisionsAround($l_rev, $r_rev);

        $l_revisions = array();
        if (!$l_rev) {
            //no left revision given, add dummy
            $l_revisions[0] = array('label' => '', 'attrs' => []);
        }
        foreach ($l_revs as $rev) {
            $info = $this->changelog->getRevisionInfo($rev);
            $l_revisions[$rev] = array(
                'label' => implode(' ', array(
                            dformat($info['date']),
                            editorinfo($info['user'], true),
                            $info['sum'],
                           )),
                'attrs' => ['title' => $rev],
            );
            if ($r_rev ? $rev >= $r_rev : false)
                $l_revisions[$rev]['attrs']['disabled'] = 'disabled';
        }

        $r_revisions = array();
        if (!$r_rev) {
            //no right revision given, add dummy
            $r_revisions[0] = array('label' => '', 'attrs' => []);
        }
        foreach ($r_revs as $rev) {
            $info = $this->changelog->getRevisionInfo($rev);
            $r_revisions[$rev] = array(
                'label' => implode(' ', array(
                            dformat($info['date']),
                            editorinfo($info['user'], true),
                            $info['sum'],
                           )),
                'attrs' => ['title' => $rev],
            );
            if ($rev <= $l_rev)
                $r_revisions[$rev]['attrs']['disabled'] = 'disabled';
        }

        //determine previous/next revisions
        $l_index = array_search($l_rev, $l_revs);
        $l_prev = $l_revs[$l_index + 1];
        $l_next = $l_revs[$l_index - 1];
        if ($r_rev) {
            $r_index = array_search($r_rev, $r_revs);
            $r_prev = $r_revs[$r_index + 1];
            $r_next = $r_revs[$r_index - 1];
        } else {
            //removed page
            $r_prev = ($l_next) ? $r_revs[0] : null;
            $r_next = null;
        }

        /*
         * Left side:
         */
        $l_nav = '';
        //move back
        if ($l_prev) {
            $l_nav .= $this->diffViewlink('diffbothprevrev', $l_prev, $r_prev);
            $l_nav .= $this->diffViewlink('diffprevrev', $l_prev, $r_rev);
        }
        //dropdown
        $form = new Form(['action' => wl()]);
        $form->setHiddenField('id', $this->id);
        $form->setHiddenField('difftype', $this->preference['difftype']);
        $form->setHiddenField('rev2[1]', $r_rev ?: 'current');
        $form->setHiddenField('do', 'diff');
        $input = $form->addDropdown('rev2[0]', $l_revisions)
            ->val($l_rev ?: 'current')->addClass('quickselect');
        $input->useInput(false); // inhibit prefillInput() during toHTML() process
        $form->addButton('do[diff]', 'Go')->attr('type','submit');
        $l_nav .= $form->toHTML();
        //move forward
        if ($l_next && ($l_next < $r_rev || !$r_rev)) {
            $l_nav .= $this->diffViewlink('diffnextrev', $l_next, $r_rev);
        }

        /*
         * Right side:
         */
        $r_nav = '';
        //move back
        if ($l_rev < $r_prev) {
            $r_nav .= $this->diffViewlink('diffprevrev', $l_rev, $r_prev);
        }
        //dropdown
        $form = new Form(['action' => wl()]);
        $form->setHiddenField('id', $this->id);
        $form->setHiddenField('rev2[0]', $l_rev ?: 'current');
        $form->setHiddenField('difftype', $this->preference['difftype']);
        $form->setHiddenField('do', 'diff');
        $input = $form->addDropdown('rev2[1]', $r_revisions)
            ->val($r_rev ?: 'current')->addClass('quickselect');
        $input->useInput(false); // inhibit prefillInput() during toHTML() process
        $form->addButton('do[diff]', 'Go')->attr('type','submit');
        $r_nav .= $form->toHTML();
        //move forward
        if ($r_next) {
            if ($this->changelog->isCurrentRevision($r_next)) {
                //last revision is diff with current page
                $r_nav .= $this->diffViewlink('difflastrev', $l_rev);
            } else {
                $r_nav .= $this->diffViewlink('diffnextrev', $l_rev, $r_next);
            }
            $r_nav .= $this->diffViewlink('diffbothnextrev', $l_next, $r_next);
        }
        return array($l_nav, $r_nav);
    }

    /**
     * Create html link to a diff view defined by two revisions
     *
     * @param string $linktype
     * @param int $lrev oldest revision
     * @param int $rrev newest revision or null for diff with current revision
     * @return string html of link to a diff view
     */
    protected function diffViewlink($linktype, $lrev, $rrev = null)
    {
        global $lang;
        if ($rrev === null) {
            $urlparam = array(
                'do' => 'diff',
                'rev' => $lrev,
                'difftype' => $this->preference['difftype'],
            );
        } else {
            $urlparam = array(
                'do' => 'diff',
                'rev2[0]' => $lrev,
                'rev2[1]' => $rrev,
                'difftype' => $this->preference['difftype'],
            );
        }
        $attr = array(
            'class' => $linktype,
            'href'  => wl($this->id, $urlparam, true, '&'),
            'title' => $lang[$linktype],
        );
        return '<a '. buildAttributes($attr) .'><span>'. $lang[$linktype] .'</span></a>';
    }


    /**
     * Insert soft breaks in diff html
     *
     * @param string $diffhtml
     * @return string
     */
    public function insertSoftbreaks($diffhtml)
    {
        // search the diff html string for both:
        // - html tags, so these can be ignored
        // - long strings of characters without breaking characters
        return preg_replace_callback('/<[^>]*>|[^<> ]{12,}/', function ($match) {
            // if match is an html tag, return it intact
            if ($match[0][0] == '<') return $match[0];
            // its a long string without a breaking character,
            // make certain characters into breaking characters by inserting a
            // word break opportunity (<wbr> tag) in front of them.
            $regex = <<< REGEX
(?(?=              # start a conditional expression with a positive look ahead ...
&\#?\\w{1,6};)     # ... for html entities - we don't want to split them (ok to catch some invalid combinations)
&\#?\\w{1,6};      # yes pattern - a quicker match for the html entity, since we know we have one
|
[?/,&\#;:]         # no pattern - any other group of 'special' characters to insert a breaking character after
)+                 # end conditional expression
REGEX;
            return preg_replace('<'.$regex.'>xu', '\0<wbr>', $match[0]);
        }, $diffhtml);
    }

}