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    <?php
    /******************************************************************************
     * Copyright (c) 2010 Jevon Wright and others.
     * All rights reserved. This program and the accompanying materials
     * are made available under the terms of the Eclipse Public License v1.0
     * which accompanies this distribution, and is available at
     * http://www.eclipse.org/legal/epl-v10.html
     *
     * Contributors:
     *    Jevon Wright - initial API and implementation
     *    Jared Hancock - html table implementation
     ****************************************************************************/
    
    /**
     * Tries to convert the given HTML into a plain text format - best suited for
     * e-mail display, etc.
     *
     * <p>In particular, it tries to maintain the following features:
     * <ul>
     *   <li>Links are maintained, with the 'href' copied over
     *   <li>Information in the &lt;head&gt; is lost
     * </ul>
     *
     * @param html the input HTML
     * @return the HTML converted, as best as possible, to text
     */
    function convert_html_to_text($html, $width=74) {
        $html = fix_newlines($html);
    
        $doc = new DOMDocument('1.0', 'utf-8');
        if (!@$doc->loadHTML($html))
            return $html;
    
        $elements = identify_node($doc);
    
        // Add the default stylesheet
        $elements->getRoot()->addStylesheet(
            HtmlStylesheet::fromArray(array(
                'p' => array('margin-bottom' => 1),
                'pre' => array('border-width' => 1, 'white-space' => 'pre'),
            ))
        );
        $options = array();
        if (is_object($elements))
            $output = $elements->render($width, $options);
        else
            $output = $elements;
    
        return trim($output);
    }
    
    /**
     * Unify newlines; in particular, \r\n becomes \n, and
     * then \r becomes \n. This means that all newlines (Unix, Windows, Mac)
     * all become \ns.
     *
     * @param text text with any number of \r, \r\n and \n combinations
     * @return the fixed text
     */
    function fix_newlines($text) {
        // replace \r\n to \n
        // remove \rs
        $text = str_replace("\r\n?", "\n", $text);
    
        return $text;
    }
    
    function identify_node($node, $parent=null) {
        if ($node instanceof DOMText)
            return $node;
        if ($node instanceof DOMDocument)
            return identify_node($node->childNodes->item(1), $parent);
        if ($node instanceof DOMDocumentType
                || $node instanceof DOMComment)
            // ignore
            return "";
    
        $name = strtolower($node->nodeName);
    
        // start whitespace
        switch ($name) {
            case "hr":
                return new HtmlHrElement($node, $parent);
            case "br":
                return "\n";
    
            case "style":
                $parent->getRoot()->addStylesheet(new HtmlStylesheet($node));
            case "title":
            case "meta":
            case "script":
            case "link":
                // ignore these tags
                return "";
    
            case "head":
            case "html":
            case "body":
            case "div":
            case "p":
            case "pre":
                return new HtmlBlockElement($node, $parent);
    
            case "blockquote":
                return new HtmlBlockquoteElement($node, $parent);
            case "cite":
                return new HtmlCiteElement($node, $parent);
    
            case "h1":
            case "h2":
            case "h3":
            case "h4":
            case "h5":
            case "h6":
                return new HtmlHeadlineElement($node, $parent);
    
            case "a":
                return new HtmlAElement($node, $parent);
    
            case "b":
            case "strong":
                return new HtmlBElement($node, $parent);
    
            case "u":
                return new HtmlUElement($node, $parent);
    
            case "ol":
                return new HtmlListElement($node, $parent);
            case "ul":
                return new HtmlUnorderedListElement($node, $parent);
    
            case 'table':
                return new HtmlTable($node, $parent);
    
            case "img":
                return new HtmlImgElement($node, $parent);
    
            case "code":
                return new HtmlCodeElement($node, $parent);
    
            default:
                // print out contents of unknown tags
                if ($node->hasChildNodes() && $node->childNodes->length == 1)
                    return identify_node($node->childNodes->item(0), $parent);
    
                return new HtmlInlineElement($node, $parent);
        }
    }
    
    class HtmlInlineElement {
        var $children = array();
        var $style = false;
        var $stylesheets = array();
        var $ws = false;
    
        function __construct($node, $parent) {
            $this->parent = $parent;
            $this->node = $node;
            $this->traverse($node);
            if ($node instanceof DomElement
                    && ($style = $this->node->getAttribute('style')))
                $this->style = new CssStyleRules($style);
        }
    
        function traverse($node) {
            if ($node->hasChildNodes()) {
                for ($i = 0; $i < $node->childNodes->length; $i++) {
                    $n = $node->childNodes->item($i);
                    $this->children[] = identify_node($n, $this);
                }
            }
        }
    
        function render($width, $options) {
            $output = '';
            $this->ws = $this->getStyle('white-space', 'normal');
            foreach ($this->children as $c) {
                if ($c instanceof DOMText) {
                    // Collapse white-space
                    switch ($this->ws) {
                        case 'pre':
                        case 'pre-wrap':
                            $more = $c->wholeText;
                            break;
                        case 'nowrap':
                        case 'pre-line':
                        case 'normal':
                        default:
                            $more = preg_replace('/\s+/m', ' ', $c->wholeText);
                    }
                }
                elseif ($c instanceof HtmlInlineElement) {
                    $more = $c->render($width, $options);
                }
                else {
                    $more = $c;
                }
                if ($more instanceof PreFormattedText)
                    $output = new PreFormattedText($output . $more);
                elseif (is_string($more))
                    $output .= $more;
            }
            return $output;
        }
    
        function getWeight() {
            if (!isset($this->weight)) {
                $this->weight = 0;
                foreach ($this->children as $c) {
                    if ($c instanceof HtmlInlineElement)
                        $this->weight += $c->getWeight();
                    elseif ($c instanceof DomText)
                        $this->weight += strlen($c->wholeText);
                }
            }
            return $this->weight;
        }
    
        function getStyle($property, $default=null, $tag=false, $classes=false) {
            if ($this->style && $this->style->has($property))
                return $this->style->get($property);
    
            if ($tag === false)
                $tag = $this->node->nodeName;
            if ($classes === false) {
                if ($c = $this->node->getAttribute('class'))
                    $classes = explode(' ', $c);
                else
                    $classes = array();
            }
    
            if ($this->stylesheets) {
                foreach ($this->stylesheets as $sheet)
                    if ($s = $sheet->get($tag, $classes))
                        return $s->get($property, $default);
            }
            elseif ($this->parent) {
                return $this->getRoot()->getStyle($property, $default, $tag, $classes);
            }
            else {
                return $default;
            }
        }
    
        function getRoot() {
            if (!$this->parent)
                return $this;
            elseif (!isset($this->root))
                $this->root = $this->parent->getRoot();
            return $this->root;
        }
    
        function addStylesheet(&$s) {
            $this->stylesheets[] = $s;
        }
    }
    
    class HtmlBlockElement extends HtmlInlineElement {
        var $min_width = false;
    
        function render($width, $options) {
            // Allow room for the border.
            // TODO: Consider left-right padding and margin
            $bw = $this->getStyle('border-width', 0);
            if ($bw)
                $width -= 4;
    
            $output = parent::render($width, $options);
            if ($output instanceof PreFormattedText)
                // TODO: Consider CSS rules
                return new PreFormattedText("\n" . $output);
    
            $output = trim($output);
            if (!strlen(trim($output)))
                return "";
    
            // Wordwrap the content to the width
            switch ($this->ws) {
                case 'nowrap':
                case 'pre':
                    break;
                case 'pre-line':
                case 'pre-wrap':
                case 'normal':
                default:
                    $output = wordwrap($output, $width, "\n", true);
            }
    
            // Apply stylesheet styles
            // TODO: Padding
            // Border
            if ($bw)
                $output = self::borderize($output, $width);
            // Margin
            $mb = $this->getStyle('margin-bottom', 0);
            $output .= str_repeat("\n", (int)$mb);
    
            return "\n" . $output;
        }
    
        function borderize($what, $width) {
            $output = ',-'.str_repeat('-', $width)."-.\n";
            foreach (explode("\n", $what) as $l)
                $output .= '| '.str_pad($l, $width)." |\n";
            $output .= '`-'.str_repeat('-', $width)."-'\n";
            return $output;
        }
    
        function getMinWidth() {
            if ($this->min_width === false) {
                foreach ($this->children as $c) {
                    if ($c instanceof HtmlBlockElement)
                        $this->min_width = max($c->getMinWidth(), $this->min_width);
                    elseif ($c instanceof DomText)
                        $this->min_width = max(max(array_map('strlen', explode(' ', $c->wholeText))),
                            $this->min_width);
                }
            }
            return $this->min_width;
        }
    }
    
    class HtmlUElement extends HtmlInlineElement {
        function render($width, $options) {
            $output = parent::render($width, $options);
            return "_".str_replace(" ", "_", $output)."_";
        }
        function getWeight() { return parent::getWeight() + 2; }
    }
    
    class HtmlBElement extends HtmlInlineElement {
        function render($width, $options) {
            $output = parent::render($width, $options);
            return "*".$output."*";
        }
        function getWeight() { return parent::getWeight() + 2; }
    }
    
    class HtmlHrElement extends HtmlBlockElement {
        function render($width, $options) {
            return "\n".str_repeat('-', $width)."\n";
        }
        function getWeight() { return 1; }
        function getMinWidth() { return 0; }
    }
    
    class HtmlHeadlineElement extends HtmlBlockElement {
        function render($width, $options) {
            $headline = parent::render($width, $options) . "\n";
            $line = false;
            switch ($this->node->nodeName) {
                case 'h1':
                case 'h2':
                    $line = '=';
                    break;
                case 'h3':
                case 'h4':
                    $line = '-';
                    break;
            }
            if ($line)
                $headline .= str_repeat($line, strpos($headline, "\n", 1) - 1) . "\n";
            return $headline;
        }
    }
    
    class HtmlBlockquoteElement extends HtmlBlockElement {
        function render($width, $options) {
            return str_replace("\n", "\n> ",
                rtrim(parent::render($width-2, $options)))."\n";
        }
        function getWeight() { return parent::getWeight()+2; }
    }
    
    class HtmlCiteElement extends HtmlBlockElement {
        function render($width, $options) {
            $options['trim'] = false;
            $lines = explode("\n", ltrim(parent::render($width-3, $options)));
            $lines[0] = "-- " . $lines[0];
            // Right justification
            foreach ($lines as &$l)
                $l = str_pad($l, $width, " ", STR_PAD_LEFT);
            unset($l);
            return implode("\n", $lines);
        }
    }
    
    class HtmlImgElement extends HtmlInlineElement {
        function render($width, $options) {
            // Images are returned as [alt: title]
            $title = $this->node->getAttribute("title");
            if ($title)
                $title = ": $title";
            $alt = $this->node->getAttribute("alt");
            return "[$alt$title] ";
        }
        function getWeight() { return parent::getWeight() + 4; }
    }
    
    class HtmlAElement extends HtmlInlineElement {
        function render($width, $options) {
            // links are returned in [text](link) format
            $output = parent::render($width, $options);
            $href = $this->node->getAttribute("href");
            if ($href == null) {
                // it doesn't link anywhere
                if ($this->node->getAttribute("name") != null) {
                    $output = "[$output]";
                }
            } else {
                if ($href != $output) {
                    $output = "[$output]($href)";
                }
            }
            return $output;
        }
        function getWeight() { return parent::getWeight() + 4; }
    }
    
    class HtmlListElement extends HtmlBlockElement {
        var $marker = "  %d. ";
    
        function render($width, $options) {
            $options['marker'] = $this->marker;
            $options['trim'] = false;
            return parent::render($width, $options);
        }
    
        function traverse($node, $number=1) {
            if ($node instanceof DOMText)
                return;
            switch (strtolower($node->nodeName)) {
                case "li":
                    $this->children[] = new HtmlListItem($node, $this->parent, $number++);
                    return;
                // Anything else is ignored
            }
            for ($i = 0; $i < $node->childNodes->length; $i++)
                $this->traverse($node->childNodes->item($i), $number);
        }
    }
    
    class HtmlUnorderedListElement extends HtmlListElement {
        var $marker = "  * ";
    }
    
    class HtmlListItem extends HtmlBlockElement {
        function HtmlListItem($node, $parent, $number) {
            parent::__construct($node, $parent);
            $this->number = $number;
        }
    
        function render($width, $options) {
            $prefix = sprintf($options['marker'], $this->number);
            $lines = explode("\n", trim(parent::render($width-strlen($prefix), $options)));
            $lines[0] = $prefix . $lines[0];
            return new PreFormattedText(
                implode("\n".str_repeat(" ", strlen($prefix)), $lines)."\n");
        }
    }
    
    class HtmlCodeElement extends HtmlInlineElement {
         function render($width, $options) {
            return '`'.parent::render($width-2, $options).'`';
        }
    }
    
    class HtmlTable extends HtmlBlockElement {
        function __construct($node, $parent) {
            $this->body = array();
            $this->foot = array();
            $this->rows = &$this->body;
            parent::__construct($node, $parent);
        }
    
        function getMinWidth() {
            if (false === $this->min_width) {
                foreach ($this->rows as $r)
                    foreach ($r as $cell)
                        $this->min_width = max($this->min_width, $cell->getMinWidth());
            }
            return $this->min_width + 4;
        }
    
        function getWeight() {
            if (!isset($this->weight)) {
                $this->weight = 0;
                foreach ($this->rows as $r)
                    foreach ($r as $cell)
                        $this->weight += $cell->getWeight();
            }
            return $this->weight;
        }
    
        function traverse($node) {
            if ($node instanceof DOMText)
                return;
    
            $name = strtolower($node->nodeName);
            switch ($name) {
                case 'th':
                case 'td':
                    $this->row[] = new HtmlTableCell($node, $this->parent);
                    // Don't descend into this node. It should be handled by the
                    // HtmlTableCell::traverse
                    return;
    
                case 'tr':
                    unset($this->row);
                    $this->row = array();
                    $this->rows[] = &$this->row;
                    break;
    
                case 'caption':
                    $this->caption = new HtmlBlockElement($node, $this->parent);
                    return;
    
                case 'tbody':
                case 'thead':
                    unset($this->rows);
                    $this->rows = &$this->body;
                    break;
    
                case 'tfoot':
                    unset($this->rows);
                    $this->rows = &$this->foot;
                    break;
            }
            for ($i = 0; $i < $node->childNodes->length; $i++)
                $this->traverse($node->childNodes->item($i));
        }
    
        /**
         * Ensure that no column is below its minimum width. Each column that is
         * below its minimum will borrow from a column that is above its
         * minimum. The process will continue until all columns are above their
         * minimums or all columns are below their minimums.
         */
        function _fixupWidths(&$widths, $mins) {
            foreach ($widths as $i=>$w) {
                if ($w < $mins[$i]) {
                    // Borrow from another column -- the furthest one away from
                    // its minimum width
                    $best = 0; $bestidx = false;
                    foreach ($widths as $j=>$w) {
                        if ($i == $j)
                            continue;
                        if ($w > $mins[$j]) {
                            if ($w - $mins[$j] > $best) {
                                $best = $w - $mins[$j];
                                $bestidx = $j;
                            }
                        }
                    }
                    if ($bestidx !== false) {
                        $widths[$bestidx]--;
                        $widths[$i]++;
                        return $this->_fixupWidths($widths, $mins);
                    }
                }
            }
        }
    
        function render($width, $options) {
            $cols = 0;
            $rows = array_merge($this->body, $this->foot);
    
            # Count the number of columns
            foreach ($rows as $r)
                $cols = max($cols, count($r));
    
            # Find the largest cells in all columns
            $weights = $mins = array_fill(0, $cols, 0);
            foreach ($rows as $r) {
                $i = 0;
                foreach ($r as $cell) {
                    for ($j=0; $j<$cell->cols; $j++) {
                        $weights[$i] = max($weights[$i], $cell->getWeight());
                        $mins[$i] = max($mins[$i], $cell->getMinWidth());
                    }
                    $i += $cell->cols;
                }
            }
    
            # Subtract internal padding and borders from the available width
            $inner_width = $width - $cols*3 - 1;
    
            # Optimal case, where the preferred width of all the columns is
            # doable
            if (array_sum($weights) <= $inner_width)
                $widths = $weights;
            # Worst case, where the minimum size of the columns exceeds the
            # available width
            elseif (array_sum($mins) > $inner_width)
                $widths = $mins;
            # Most likely case, where the table can be fit into the available
            # width
            else {
                $total = array_sum($weights);
                $widths = array();
                foreach ($weights as $c)
                    $widths[] = (int)($inner_width * $c / $total);
                $this->_fixupWidths($widths, $mins);
            }
            $outer_width = array_sum($widths) + $cols*3 + 1;
    
            $contents = array();
            $heights = array();
            foreach ($rows as $y=>$r) {
                $heights[$y] = 0;
                for ($x = 0, $i = 0; $x < $cols; $i++) {
                    if (!isset($r[$i])) {
                        // No cell at the end of this row
                        $contents[$y][$i][] = "";
                        break;
                    }
                    $cell = $r[$i];
                    # Compute the effective cell width for spanned columns
                    # Add extra space for the unneeded border padding for
                    # spanned columns
                    $cwidth = ($cell->cols - 1) * 3;
                    for ($j = 0; $j < $cell->cols; $j++)
                        $cwidth += $widths[$x+$j];
                    # Stash the computed width so it doesn't need to be
                    # recomputed again below
                    $cell->width = $cwidth;
                    unset($data);
                    $data = explode("\n", $cell->render($cwidth, $options));
                    $heights[$y] = max(count($data), $heights[$y]);
                    $contents[$y][$i] = &$data;
                    $x += $cell->cols;
                }
            }
    
            # Build the header
            $header = "";
            for ($i = 0; $i < $cols; $i++)
                $header .= "+-" . str_repeat("-", $widths[$i]) . "-";
            $header .= "+";
    
            # Emit the rows
            $output = "\n";
            if (isset($this->caption)) {
                $this->caption = $this->caption->render($outer_width, $options);
            }
            foreach ($rows as $y=>$r) {
                $output .= $header . "\n";
                for ($x = 0, $k = 0; $k < $heights[$y]; $k++) {
                    $output .= "|";
                    foreach ($r as $x=>$cell) {
                        $content = (isset($contents[$y][$x][$k]))
                            ? $contents[$y][$x][$k] : "";
                        $pad = $cell->width - mb_strlen($content, 'utf8');
                        $output .= " ".$content;
                        if ($pad > 0)
                            $output .= str_repeat(" ", $pad);
                        $output .= " |";
                        $x += $cell->cols;
                    }
                    $output .= "\n";
                }
            }
            $output .= $header . "\n";
            return new PreFormattedText($output);
        }
    }
    
    class HtmlTableCell extends HtmlBlockElement {
        function __construct($node, $parent) {
            parent::__construct($node, $parent);
            $this->cols = $node->getAttribute('colspan');
            $this->rows = $node->getAttribute('rowspan');
    
            if (!$this->cols) $this->cols = 1;
            if (!$this->rows) $this->rows = 1;
        }
    
        function render($width, $options) {
            return ltrim(parent::render($width, $options));
        }
    
        function getWeight() {
            return parent::getWeight() / ($this->cols * $this->rows);
        }
    
        function getMinWidth() {
            return parent::getMinWidth() / $this->cols;
        }
    }
    
    class HtmlStylesheet {
        function __construct($node=null) {
            if (!$node) return;
    
            // We really only care about tags and classes
            $rules = array();
            preg_match_all('/([^{]+)\{((\s*[\w-]+:\s*[^;}]+;?)+)\s*\}/m',
                $node->textContent, $rules, PREG_SET_ORDER);
    
            $this->rules = array();
            $m = array();
            foreach ($rules as $r) {
                list(,$selector,$props) = $r;
                $props = new CssStyleRules($props);
                foreach (explode(',', $selector) as $s) {
                    // Only allow tag and class selectors
                    if (preg_match('/^([\w-]+)?(\.[\w_-]+)?$/m', trim($s), $m))
                        // XXX: Technically, a selector could be listed more
                        // than once, and the rules should be aggregated.
                        $this->rules[$m[0]] = &$props;
                }
                unset($props);
            }
        }
    
        function get($tag, $classes=array()) {
            // Honor CSS specificity
            foreach ($this->rules as $selector=>$rules)
                foreach ($classes as $c)
                    if ($selector == "$tag.$c" || $selector == ".$c")
                        return $rules;
            foreach ($this->rules as $selector=>$rules)
                if ($selector == $tag)
                    return $rules;
        }
    
        static function fromArray($selectors) {
            $self = new HtmlStylesheet();
            foreach ($selectors as $s=>$rules)
                $self->rules[$s] = CssStyleRules::fromArray($rules);
            return $self;
        }
    }
    
    class CssStyleRules {
        var $rules = array();
    
        function __construct($rules) {
            foreach (explode(';', $rules) as $r) {
                if (strpos($r, ':') === false)
                    continue;
                list($prop, $val) = explode(':', $r);
                $this->rules[trim($prop)] = trim($val);
                // TODO: Explode compact rules, like 'border', 'margin', etc.
            }
        }
    
        function has($prop) {
            return isset($this->rules[$prop]);
        }
    
        function get($prop, $default=0.0) {
            if (!isset($this->rules[$prop]))
                return $default;
            else
                $val = $this->rules[$prop];
    
            if (is_string($val)) {
                switch (true) {
                    case is_float($default):
                        $simple = floatval($val);
                        $units = substr($val, -2);
                        // Cache the conversion
                        $val = $this->rules[$prop] = self::convert($simple, $units);
                }
            }
            return $val;
        }
    
        static function convert($value, $units) {
            if ($value === null)
                return $value;
    
            // Converts common CSS units to units of characters
            switch ($units) {
                case 'px':
                    return $value / 20.0;
                case 'pt':
                    return $value / 12.0;
                case 'em':
                default:
                    return $value;
            }
        }
    
        static function fromArray($rules) {
            $self = new CssStyleRules('');
            $self->rules = &$rules;
            return $self;
        }
    }
    
    class PreFormattedText {
        function __construct($text) {
            $this->text = $text;
        }
        function __toString() {
            return $this->text;
        }
    }
    
    // Enable use of html2text from command line
    // The syntax is the following: php html2text.php file.html
    
    do {
      if (PHP_SAPI != 'cli') break;
      if (empty ($_SERVER['argc']) || $_SERVER['argc'] < 2) break;
      if (empty ($_SERVER['PHP_SELF']) || FALSE === strpos ($_SERVER['PHP_SELF'], 'html2text.php') ) break;
      $file = $argv[1];
      $width = 74;
      if (isset($argv[2]))
          $width = (int) $argv[2];
      echo convert_html_to_text (file_get_contents ($file), $width);
    } while (0);