function Markdown_Parser::doItalicsAndBold in Markdown 5

Same name and namespace in other branches

1. 6 markdown.php \Markdown_Parser::doItalicsAndBold()

File

./markdown.php, line 1153

Class

Markdown_Parser

Code

function doItalicsAndBold($text) {
  $token_stack = array(
    '',
  );
  $text_stack = array(
    '',
  );
  $em = '';
  $strong = '';
  $tree_char_em = false;
  while (1) {

    #

    # Get prepared regular expression for seraching emphasis tokens

    # in current context.

    #
    $token_re = $this->em_strong_prepared_relist["{$em}{$strong}"];

    #

    # Each loop iteration seach for the next emphasis token.

    # Each token is then passed to handleSpanToken.

    #
    $parts = preg_split($token_re, $text, 2, PREG_SPLIT_DELIM_CAPTURE);
    $text_stack[0] .= $parts[0];
    $token =& $parts[1];
    $text =& $parts[2];
    if (empty($token)) {

      # Reached end of text span: empty stack without emitting.

      # any more emphasis.
      while ($token_stack[0]) {
        $text_stack[1] .= array_shift($token_stack);
        $text_stack[0] .= array_shift($text_stack);
      }
      break;
    }
    $token_len = strlen($token);
    if ($tree_char_em) {

      # Reached closing marker while inside a three-char emphasis.
      if ($token_len == 3) {

        # Three-char closing marker, close em and strong.
        array_shift($token_stack);
        $span = array_shift($text_stack);
        $span = $this
          ->runSpanGamut($span);
        $span = "<strong><em>{$span}</em></strong>";
        $text_stack[0] .= $this
          ->hashPart($span);
        $em = '';
        $strong = '';
      }
      else {

        # Other closing marker: close one em or strong and

        # change current token state to match the other
        $token_stack[0] = str_repeat($token[0], 3 - $token_len);
        $tag = $token_len == 2 ? "strong" : "em";
        $span = $text_stack[0];
        $span = $this
          ->runSpanGamut($span);
        $span = "<{$tag}>{$span}</{$tag}>";
        $text_stack[0] = $this
          ->hashPart($span);
        ${$tag} = '';

        # $$tag stands for $em or $strong
      }
      $tree_char_em = false;
    }
    else {
      if ($token_len == 3) {
        if ($em) {

          # Reached closing marker for both em and strong.

          # Closing strong marker:
          for ($i = 0; $i < 2; ++$i) {
            $shifted_token = array_shift($token_stack);
            $tag = strlen($shifted_token) == 2 ? "strong" : "em";
            $span = array_shift($text_stack);
            $span = $this
              ->runSpanGamut($span);
            $span = "<{$tag}>{$span}</{$tag}>";
            $text_stack[0] .= $this
              ->hashPart($span);
            ${$tag} = '';

            # $$tag stands for $em or $strong
          }
        }
        else {

          # Reached opening three-char emphasis marker. Push on token

          # stack; will be handled by the special condition above.
          $em = $token[0];
          $strong = "{$em}{$em}";
          array_unshift($token_stack, $token);
          array_unshift($text_stack, '');
          $tree_char_em = true;
        }
      }
      else {
        if ($token_len == 2) {
          if ($strong) {

            # Unwind any dangling emphasis marker:
            if (strlen($token_stack[0]) == 1) {
              $text_stack[1] .= array_shift($token_stack);
              $text_stack[0] .= array_shift($text_stack);
            }

            # Closing strong marker:
            array_shift($token_stack);
            $span = array_shift($text_stack);
            $span = $this
              ->runSpanGamut($span);
            $span = "<strong>{$span}</strong>";
            $text_stack[0] .= $this
              ->hashPart($span);
            $strong = '';
          }
          else {
            array_unshift($token_stack, $token);
            array_unshift($text_stack, '');
            $strong = $token;
          }
        }
        else {

          # Here $token_len == 1
          if ($em) {
            if (strlen($token_stack[0]) == 1) {

              # Closing emphasis marker:
              array_shift($token_stack);
              $span = array_shift($text_stack);
              $span = $this
                ->runSpanGamut($span);
              $span = "<em>{$span}</em>";
              $text_stack[0] .= $this
                ->hashPart($span);
              $em = '';
            }
            else {
              $text_stack[0] .= $token;
            }
          }
          else {
            array_unshift($token_stack, $token);
            array_unshift($text_stack, '');
            $em = $token;
          }
        }
      }
    }
  }
  return $text_stack[0];
}