PHP_Highlight.php

<?php

/**
 * PHP 5 added a set of new constants which need to be declared in this file for
 * effective PHP 5 highlighting. It also removed constants, which need to be
 * included for PHP 4 highlighting.
 *
 * The following file will define constants for PHP 4 / PHP 5 compatability
 *
 * The source of this file can be found at:
 * http://tinyurl.com/plmlo
 *
 * It is part of the PEAR PHP_Compat package:
 * http://pear.php.net/package/PHP_Compat
 */
require_once 'PHP/Compat/Constant/T.php';


/**
 * Improved PHP syntax highlighting.
 *
 * Generates valid XHTML output with function referencing
 * and line numbering.
 *
 * Extendable output methods provide maximum flexibility,
 * toHtml(), toHtmlComment(), toList() and toArray().
 *
 * Highlighting can be inline (with styles), or the same as
 * highlight_file() where colors are taken from php.ini.
 *
 * @author      Aidan Lister <aidan@php.net>
 * @version     1.4.3
 * @link        http://aidanlister.com/repos/v/PHP_Highlight.php
 */
class PHP_Highlight
{
    /**
     * Hold highlight colors
     *
     * Contains an associative array of token types and colours.
     * By default, it contains the colours as specified by php.ini
     *
     * For example, to change the colour of strings, use something
     * simular to $h->highlight['string'] = 'blue';
     *
     * @var         array
     * @access      public
     */
    var $highlight;

    /**
     * Things to be replaced for formatting or otherwise reasons
     *
     * The first element contains the match array, the second the replace
     * array.
     *
     * @var         array
     * @access      public
     */
    var $replace = array(
        "\t"    => '&nbsp;&nbsp;&nbsp;&nbsp;',
        ' '     => '&nbsp;');

    /**
     * Format of the link to the PHP manual page
     *
     * @var         string
     * @access      public
     */
    var $manual = '<a href="http://www.php.net/function.%s">%s</a>';

    /**
     * Format of the span tag to be wrapped around each token
     *
     * @var         string
     * @access      public
     */
    var $span;

    /**
     * Hold the source
     *
     * @var         string
     * @access      private
     */
    var $_source = false;

    /**
     * Hold plaintext keys
     *
     * An array of lines which are plaintext
     *
     * @var         array
     * @access      private
     */
    var $_plaintextkeys = array();


    /**
     * Constructor
     *
     * Populates highlight array
     *
     * @param   bool  $inline     If inline styles rather than colors are to be used
     * @param   bool  $plaintext  Do not format code outside PHP tags
     */
    function PHP_Highlight($inline = false)
    {
        // Inline
        if ($inline === false) {
            // Default colours from php.ini
            $this->highlight = array(
                'string'    => ini_get('highlight.string'),
                'comment'   => ini_get('highlight.comment'),
                'keyword'   => ini_get('highlight.keyword'),
                'bg'        => ini_get('highlight.bg'),
                'default'   => ini_get('highlight.default'),
                'html'      => ini_get('highlight.html')
            );
            $this->span = '<span style="color: %s;">%s</span>';
        } else {
            // Basic styles
            $this->highlight = array(
                'string'    => 'string',
                'comment'   => 'comment',
                'keyword'   => 'keyword',
                'bg'        => 'bg',
                'default'   => 'default',
                'html'      => 'html'
            );
            $this->span = '<span class="%s">%s</span>';
        }
    }


    /**
     * Load a file
     *
     * @access  public
     * @param   string      $file       The file to load
     * @return  bool        Returns TRUE
     */
    function loadFile($file)
    {
        $this->_source = file_get_contents($file);
        return true;
    }


    /**
     * Load a string
     *
     * @access  public
     * @param   string      $string     The string to load
     * @return  bool        Returns TRUE
     */
    function loadString($string)
    {
        $this->_source = $string;
        return true;
    }


    /**
     * Parse the loaded string into an array
     * Source is returned with the element key corresponding to the line number
     *
     * @access  public
     * @param   bool      $funcref   Reference functions to the PHP manual
     * @param   bool      $blocks    Whether to ignore processing plaintext
     * @return  array     An array of highlighted source code
     */
    function toArray($funcref = true, $blocks = false)
    {
        // Ensure source has been loaded
        if ($this->_source == false) {
            return false;
        }

        // Init
        $tokens     = token_get_all($this->_source);
        $manual     = $this->manual;
        $span       = $this->span;
        $stringflag = false;
        $i          = 0;
        $out        = array();
        $out[$i]    = '';

        // Loop through each token
        foreach ($tokens as $j => $token) {
            // Single char
            if (is_string($token)) {

                // Entering or leaving a quoted string
                if ($token === '"' && $tokens[$j - 1] !== '\\') {
                    $stringflag = !$stringflag;
                    $out[$i] .= sprintf($span, $this->highlight['string'], $token);
                } else {
                    // Skip token2color check for speed
                    $out[$i] .= sprintf($span, $this->highlight['keyword'], htmlspecialchars($token));

                    // Heredocs behave strangely
                    list($tb) = isset($tokens[$j - 1]) ? $tokens[$j - 1] : false;
                    if ($tb === T_END_HEREDOC) {
                        $out[++$i] = '';
                    }
                }

                continue;
            }

            // Proper token
            list ($token, $value) = $token;

            // Make the value safe
            $value = htmlspecialchars($value);
            $value = str_replace(
                        array_keys($this->replace),
                        array_values($this->replace),
                        $value);

            // Process
            if ($value === "\n") {
                // End this line and start the next
                $out[++$i] = '';
            } else {
                // Function linking
                if ($funcref === true && $token === T_STRING) {
                    // Look ahead 1, look ahead 2, and look behind 3
                    // For a function we expect T_FUNCTION T_STRING [T_WHITESPACE] (
                    if ((isset($tokens[$j + 1]) && $tokens[$j + 1] === '(' ||
                        isset($tokens[$j + 2]) && $tokens[$j + 2] === '(') &&
                        isset($tokens[$j - 3][0]) && $tokens[$j - 3][0] !== T_FUNCTION
                        && function_exists($value)) {

                        // Insert the manual link
                        $value = sprintf($manual, $value, $value);
                    }
                }

                // Explode token block
                $lines = explode("\n", $value);
                foreach ($lines as $jj => $line) {
                    $line = trim($line);
                    if ($line !== '') {
                        // Uncomment for debugging
                        //$out[$i] .= token_name($token);

                        // Check for plaintext
                        if ($blocks === true && $token === T_INLINE_HTML) {
                            $this->_plaintextkeys[] = $i;
                            $out[$i] .= $line;
                        } else {
                            // Highlight encased strings
                            $colour = ($stringflag === true) ?
                                $this->highlight['string'] :
                                $this->_token2color($token);
                            $out[$i] .= sprintf($span, $colour, $line);
                        }
                    }


                    // Start a new line
                    if (isset($lines[$jj + 1])) {
                        $out[++$i] = '';
                    }
                }
            }
        }

        return $out;
    }


    /**
     * Convert the source to an ordered list.
     * Each line is wrapped in <li> tags.
     *
     * @access  public
     * @param   bool      $return    Return rather than print the results
     * @param   bool      $funcref   Reference functions to the PHP manual
     * @param   bool      $blocks    Whether to use code blocks around plaintext
     * @return  string    A HTML ordered list
     */
    function toList($return = false, $funcref = true, $blocks = true)
    {
        // Ensure source has been loaded
        if ($this->_source == false) {
            return false;
        }

        // Format list
        $source = $this->toArray($funcref, $blocks);
        $out = "<ol>\n";
        foreach ($source as $i => $line) {
            $out .= "    <li>";

            // Some extra juggling for lines which are not code
            if (empty($line)) {
                $out .= '&nbsp;';
            } elseif ($blocks === true && in_array($i, $this->_plaintextkeys)) {
                $out .= $line;
            } else {
                $out .= "<code>$line</code>";
            }

            $out .= "</li>\n";
        }
        $out .= "</ol>\n";

        if ($return === true) {
            return $out;
        } else {
            echo $out;
        }
    }


    /**
     * Convert the source to formatted HTML.
     * Each line ends with <br />.
     *
     * @access  public
     * @param   bool      $return       Return rather than print the results
     * @param   bool      $linenum      Display line numbers
     * @param   string    $format       Specify format of line numbers displayed
     * @param   bool      $funcref      Reference functions to the PHP manual
     * @return  string    A HTML block of code
     */
    function toHtml($return = false, $linenum = false, $format = null, $funcref = true)
    {
        // Ensure source has been loaded
        if ($this->_source == false) {
            return false;
        }

        // Line numbering
        if ($linenum === true && $format === null) {
            $format = '<span>%02d</span> ';
        }

        // Format code
        $source = $this->toArray($funcref);
        $out = "<code>\n";
        foreach ($source as $i => $line) {
            $out .= '    ';

            if ($linenum === true) {
                $out .= sprintf($format, $i);
            }

            $out .= empty($line) ? '&nbsp;' : $line;
            $out .= "<br />\n";
        }
        $out .= "</code>\n";

        if ($return === true) {
            return $out;
        } else {
            echo $out;
        }
    }


    /**
     * Convert the source to formatted HTML blocks.
     * Each line ends with <br />.
     *
     * This method ensures only PHP is between <<code>> blocks.
     *
     * @access  public
     * @param   bool      $return       Return rather than print the results
     * @param   bool      $linenum      Display line numbers
     * @param   string    $format       Specify format of line numbers displayed
     * @param   bool      $reset        Reset the line numbering each block
     * @param   bool      $funcref      Reference functions to the PHP manual
     * @return  string    A HTML block of code
     */
    function toHtmlBlocks($return = false, $linenum = false, $format = null, $reset = true, $funcref = true)
    {
        // Ensure source has been loaded
        if ($this->_source == false) {
            return false;
        }

        // Default line numbering
        if ($linenum === true && $format === null) {
            $format = '<span>%03d</span> ';
        }

        // Init
        $source     = $this->toArray($funcref, true);
        $out        = '';
        $wasplain   = true;
        $k          = 0;

        // Loop through each line and decide which block to use
        foreach ($source as $i => $line) {
            // Empty line
            if (empty($line)) {
                if ($wasplain === true) {
                    $out .= '&nbsp;';
                } else {
                    if (in_array($i+1, $this->_plaintextkeys)) {
                        $out .= "</code>\n";

                        // Reset line numbers
                        if ($reset === true) {
                            $k = 0;
                        }
                    } else {
                        $out .= '     ';
                        // Add line number
                        if ($linenum === true) {
                            $out .= sprintf($format, ++$k);
                        }
                    }
                }

            // Plain text
            } elseif (in_array($i, $this->_plaintextkeys)) {
                if ($wasplain === false) {
                    $out .= "</code>\n";

                    // Reset line numbers
                    if ($reset === true) {
                        $k = 0;
                    }
                }

                $wasplain = true;
                $out .= str_replace('&nbsp;', ' ', $line);

            // Code
            } else {
                if ($wasplain === true) {
                    $out .= "<code>\n";
                }
                $wasplain = false;

                $out .= '     ';
                // Add line number
                if ($linenum === true) {
                    $out .= sprintf($format, ++$k);
                }
                $out .= $line;
            }

            $out .= "<br />\n";
        }

        // Add final code tag
        if ($wasplain === false) {
            $out .= "</code>\n";
        }

        // Output method
        if ($return === true) {
            return $out;
        } else {
            echo $out;
        }
    }


    /**
     * Assign a color based on the name of a token
     *
     * @access  private
     * @param   int     $token      The token
     * @return  string  The color of the token
     */
    function _token2color($token)
    {
        switch ($token):
            case T_CONSTANT_ENCAPSED_STRING:
                return $this->highlight['string'];
                break;

            case T_INLINE_HTML:
                return $this->highlight['html'];
                break;

            case T_COMMENT:
            case T_DOC_COMMENT:
            case T_ML_COMMENT:
                return $this->highlight['comment'];
                break;

            case T_ABSTRACT:
            case T_ARRAY:
            case T_ARRAY_CAST:
            case T_AS:
            case T_BOOLEAN_AND:
            case T_BOOLEAN_OR:
            case T_BOOL_CAST:
            case T_BREAK:
            case T_CASE:
            case T_CATCH:
            case T_CLASS:
            case T_CLONE:
            case T_CONCAT_EQUAL:
            case T_CONTINUE:
            case T_DEFAULT:
            case T_DOUBLE_ARROW:
            case T_DOUBLE_CAST:
            case T_ECHO:
            case T_ELSE:
            case T_ELSEIF:
            case T_EMPTY:
            case T_ENDDECLARE:
            case T_ENDFOR:
            case T_ENDFOREACH:
            case T_ENDIF:
            case T_ENDSWITCH:
            case T_ENDWHILE:
            case T_END_HEREDOC:
            case T_EXIT:
            case T_EXTENDS:
            case T_FINAL:
            case T_FOREACH:
            case T_FUNCTION:
            case T_GLOBAL:
            case T_IF:
            case T_INC:
            case T_INCLUDE:
            case T_INCLUDE_ONCE:
            case T_INSTANCEOF:
            case T_INT_CAST:
            case T_ISSET:
            case T_IS_EQUAL:
            case T_IS_IDENTICAL:
            case T_IS_NOT_IDENTICAL:
            case T_IS_SMALLER_OR_EQUAL:
            case T_NEW:
            case T_OBJECT_CAST:
            case T_OBJECT_OPERATOR:
            case T_PAAMAYIM_NEKUDOTAYIM:
            case T_PRIVATE:
            case T_PROTECTED:
            case T_PUBLIC:
            case T_REQUIRE:
            case T_REQUIRE_ONCE:
            case T_RETURN:
            case T_SL:
            case T_SL_EQUAL:
            case T_SR:
            case T_SR_EQUAL:
            case T_START_HEREDOC:
            case T_STATIC:
            case T_STRING_CAST:
            case T_SWITCH:
            case T_THROW:
            case T_TRY:
            case T_UNSET_CAST:
            case T_VAR:
            case T_WHILE:
                return $this->highlight['keyword'];
                break;

            case T_CLOSE_TAG:
            case T_OPEN_TAG:
            case T_OPEN_TAG_WITH_ECHO:
            default:
                return $this->highlight['default'];

        endswitch;
    }
}