system/classes/hiengine.php

<?php
namespace Habari;
class HiEngine extends RawPHPEngine {
  public function __construct()
  {
    $streams = stream_get_wrappers();
    if ( ! in_array( 'hi', $streams ) ) {
      stream_wrapper_register( "hi", "\Habari\HiEngineParser" )
      or die( _t( "Failed to register HiEngine stream protocol" ) );
    }
  }

  public function display( $template )
  {
    extract( $this->engine_vars );
    //Utils::debug($this->engine_vars);die();
    if ( $this->template_exists( $template ) ) {
      $template_file = isset( $this->template_map[$template] ) ? $this->template_map[$template] : null;
      $template_file = Plugins::filter( 'include_template_file', $template_file, $template, __CLASS__ );
      $template_file = 'hi://' . $template_file;
      $fc = file_get_contents( $template_file );
      //echo($fc);
      eval( 'namespace Habari; ?'.'>' . $fc );
      //include $template_file;  // stopped working properly in PHP 5.2.8 
    }
  }
}

class HiEngineParser
{
  protected $file;
  protected $filename;
  protected $position;
  protected $contexts;
  protected $strings = array();

  function stream_open( $path, $mode, $options, &$opened_path )
  {
    $this->filename = substr( $path, 5 );
    $this->file = file_get_contents( $this->filename );

    // This processed value should cache and invalidate if a checksum of the template changes!  :)
    $this->file = $this->process( $this->file );

    $this->position = 0;

    return true;
  }

  function stream_read( $count )
  {
    if ( $this->stream_eof() ) {
      return false;
    }
    $ret = substr( $this->file, $this->position, $count );
    $this->position += strlen( $ret );
    return $ret;
  }

  function stream_write( $data )
  {
    // HiEngineParser streams are read-only
    return false;
  }

  function stream_tell()
  {
    return $this->position;
  }

  function stream_eof()
  {
    return $this->position >= strlen( $this->file );
  }

  function stream_seek( $offset, $whence )
  {
    switch ( $whence ) {
      case SEEK_SET:
        if ( $offset < strlen( $this->file ) && $offset >= 0 ) {
          $this->position = $offset;
          return true;
        }
        else {
          return false;
        }
        break;

      case SEEK_CUR:
        if ( $offset >= 0 ) {
          $this->position += $offset;
          return true;
        }
        else {
          return false;
        }
        break;

      case SEEK_END:
        if ( strlen( $this->file ) + $offset >= 0 ) {
          $this->position = strlen( $this->file ) + $offset;
          return true;
        }
        else {
          return false;
        }
        break;

      default:
        return false;
    }
    
  }

  function stream_stat()
  {
    return array();
  }

  function process( $template )
  {
    $template = preg_replace_callback( '/\{hi:(".+?")((?:\s*[\w\.]+){0,2})\s*\}/smu', array( $this, 'hi_quote' ), $template );
    $template = preg_replace_callback( '%\{hi:([^\?]+?)\}(.+?)\{/hi:\1\}%ism', array( $this, 'hi_loop' ), $template );
    $template = preg_replace_callback( '%\{hi:\?\s*(.+?)\}(.+?)\{/hi:\?\}%ismu', array( $this, 'hi_if' ), $template );
    $template = preg_replace_callback( '%\{hi:([^:}]+?:.+?)\}%i', array( $this, 'hi_command' ), $template );
    $template = preg_replace_callback( '%\{hi:(.+?)\}%i', array( $this, 'hi_var' ), $template );
    return $template;
  }
  
  function hi_command( $matches )
  {
    $cmd = trim( $matches[1] );

    // Catch tags in the format {hi:command:parameter}
    if ( preg_match( '/^(\w+):(.+)$/u', $cmd, $cmd_matches ) ) {
      switch ( strtolower( $cmd_matches[1] ) ) {
        case 'area':
          return '<?php echo $theme->area(\'' . $cmd_matches[2] . '\'); ?>';
        case 'display':
          return '<?php $theme->display(\'' . $cmd_matches[2] . '\'); ?>';
        case 'option':
        case 'options':
          return '<?php Options::out(\'' . $cmd_matches[2] . '\'); ?>';
        case 'siteurl':
          return '<?php Site::out_url( \'' . $cmd_matches[2] . '\' ); ?>';
        case 'url':
          return '<?php URL::out( \'' . $cmd_matches[2] . '\' ); ?>';
        case 'session':
          switch ( $cmd_matches[2] ) {
            case 'messages':
              return '<?php if (Session::has_messages()){Session::messages_out();} ?>';
            case 'errors':
              return '<?php if (Session::has_errors()){Session::messages_out();} ?>';
          }
        // this is an internal match
        case 'context':
          return $this->hi_to_var( $cmd_matches[2] );
        case 'escape':
          return '<?php echo Utils::htmlspecialchars( ' . $this->hi_to_var( $cmd_matches[2] ) . ' ); ?>';
      }
    }
    
    return $matches[0];
  }

  function hi_var( $matches )
  {
    $cmd = trim( $matches[1] );
    $params = array();
    $returnval = false;

    if ( preg_match_all( '/(?<=\s)(?P<name>[@a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff.]*)\s*=\s*(?P<value>(?P<quot>["\']).+?\3|[^"\'\s]+)/i', $cmd, $foundparams, PREG_SET_ORDER ) ) {
      foreach ( $foundparams as $p ) {
        $params[$p['name']] = trim( $p['value'], $p['quot'] );
      }
    }

    // Straight variable or property output, ala {hi:variable_name} or {hi:post.title}
    if ( preg_match( '%(^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff.]*)%i', $cmd, $cmdmatch ) ) {
      $cmdmatch = str_replace( '.', '->', $cmdmatch[1] );
      if ( count( $this->contexts ) ) {
        // Build a conditional that checks for the most specific, then the least
        // eg.- $a->b->c->d->x, then $a->b->c->x, down to just $x
        $ctx = $this->contexts;
        $prefixes = array();
        foreach ( $ctx as $void ) {
          $prefixes[] = implode( '->', $this->contexts );
          array_pop( $ctx );
        }
        $output = '';
        foreach ( $prefixes as $prefix ) {
          $output .= '(is_object($' . $prefix . ') && !'.'is_null($' . $prefix . '->' . $cmdmatch . ')) ? $' . $prefix . '->' . $cmdmatch . ' : ';
        }
        $output .= '$' . $cmdmatch;
        $returnval = $output;
      }
      else {
        $returnval = '$'. $cmdmatch;
      }
    }
    if ( $returnval !== false ) {
      $returnval = $this->apply_parameters( $returnval, $params );
      return '<?php echo '. $returnval . '; ?>';
    }

    // Use tags in the format {hi:@foo} as theme functions, ala $theme->foo();
    if ( $cmd[0] == '@' ) {
      return '<?php $theme->' . substr( $cmd, 1 ) . '(); ?>';
    }

    // Didn't match anything we support so far
    return $matches[0];
  }
  
  function apply_parameters( $returnval, $params )
  {
    foreach ( $params as $k => $v ) {
      if ( $k[0] == '@' ) {
        $returnval = '$theme->' . substr( $k, 1 ) . '(' . $returnval . ", '" . $v . "')";
      }
      switch ( $k ) {
        case 'dateformat':
          $returnval = "call_user_func(array(" . $returnval . ", 'format'), '" . addslashes( $v ) . "')";
          break; 
      }
    }
    return $returnval;
  }

  function hi_loop( $matches )
  {
    $hivar = $matches[1];
    $phpvar = $this->hi_to_var( $hivar );
    $iterator = strpos( $hivar, '.' ) ? substr( $hivar, strrpos( $hivar, '.' ) + 1 ) : $hivar;
    $output = '<?php foreach(' . $phpvar . ' as $' . $iterator . '_index => $' . $iterator . '_1): ?>';
    $this->contexts[] = "{$iterator}_1";
    $output .= $this->process( $matches[2] );
    $output .= '<?php endforeach; ?>';
    array_pop( $this->contexts );
    return $output;
  }

  function var_replace( $matches )
  {
    $var = $matches[1];

    if ( is_callable( $var ) ) {
      return $var;
    }
    if ( preg_match( '/true|false|null|isset|empty/i', $var ) ) {
      return $var;
    }

    $var = $this->hi_to_var( $var );

    return $var;
  }

  function hi_to_var( $hisyntax )
  {
    $var = str_replace( '.', '->', $hisyntax );
    if ( count( $this->contexts ) ) {
      // Build a conditional that checks for the most specific, then the least
      // eg.- $a->b->c->d->x, then $a->b->c->x, down to just $x
      $ctx = $this->contexts;
      $prefixes = array();
      foreach ( $ctx as $void ) {
        $prefixes[] = implode( '->', $this->contexts );
        array_pop( $ctx );
      }
      $output = '';
      foreach ( $prefixes as $prefix ) {
        $output .= '(!is_null($' . $prefix . '->' . $var . ') ? $' . $prefix . '->' . $var . ' : ';
      }
      $output .= '$' . $var . ')';
      return $output;
    }
    else {
      return '$'. $var;
    }
  }

  function string_stack( $matches )
  {
    $key = chr( 0 ) . count( $this->strings ) . chr( 1 );
    $this->strings[$key] = $matches[0];
    return $key;
  }

  function hi_if ( $matches )
  {
    list( $void, $eval, $context ) = $matches;

    $eval = preg_replace_callback( '/([\'"]).*?(?<!\\\\)\1/i', array( $this, 'string_stack' ), $eval );
    $eval = preg_replace_callback( '/\b((?<!::)[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff.]*(?!::))\b/i', array( $this, 'var_replace' ), $eval );
    $eval = preg_replace( '/(?<!=)=(?!=)/i', '==', $eval );
    $eval = str_replace( array_keys( $this->strings ), $this->strings, $eval );

    $context = preg_replace( '/\{hi:\?else\?\}/i', '<?php else: ?>', $context );

    $output = '<?php if (' . $eval . '): ?>';
    $output .= $this->process( $context );
    $output .= '<?php endif; ?>';
    return $output;
  }

  function hi_quote( $matches )
  {
    $args = preg_split( '/\s+/u', trim( $matches[2] ) );

    preg_match_all( '/"(.+?)(?<!\\\\)"/', $matches[1], $quotes );
    $count = 0;
    $all_vars = array();
    foreach ( $quotes[1] as $index => $quote ) {
      preg_match_all( '/{hi:([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff.]*)}/', $quote, $vars, PREG_SET_ORDER );
      foreach ( $vars as $var ) {
        $count++;
        $quote = str_replace( $var[0], '%'.$count.'\$s', $quote );
        $all_vars[] = '{hi:context:' . $var[1] . '}';  //$this->hi_to_var($var[1]);
      }
      $quotes[1][$index] = $quote;
    }
    if ( count( $quotes[1] ) > 1 ) {
      $output = '<?php printf(_n("'.$quotes[1][0].'", "'.$quotes[1][1].'", {hi:context:'.$args[0].'})';
      // Add vars
      if ( count( $all_vars ) > 0 ) {
        $output .= ', ' . implode( ', ', $all_vars );
      }
      array_shift( $args );
    }
    else {
      $output = '<?php _e("'.$quotes[1][0].'"';
      // Add vars
      if ( count( $all_vars ) > 0 ) {
        $output .= ', array(' . implode( ', ', $all_vars ) . ')';
      }
    }

    // Add the domain, if any
    if ( isset( $args[0] ) ) {
      $output .= ', "'.$args[0].'"';
    }

    // Close the tag
    $output .= '); ?>';

    return $output;
  }
}

?>