comments and descriptive variable names

diff --git a/includes/Parser.php b/includes/Parser.php
index 7334548..dfcf970 100644 (file)
--- a/includes/Parser.php
+++ b/includes/Parser.php
@@ -1048,6 +1048,7 @@ class Parser
        /* private */ function replaceExternalLinks( $text ) {
                $fname = 'Parser::replaceExternalLinks';
                wfProfileIn( $fname );
+
                $text = $this->subReplaceExternalLinks( $text, 'http', true );
                $text = $this->subReplaceExternalLinks( $text, 'https', true );
                $text = $this->subReplaceExternalLinks( $text, 'ftp', false );
@@ -1059,8 +1060,11 @@ class Parser
                return $text;
        }
 
+       # Replaces all external links with a given protocol
        /* private */ function subReplaceExternalLinks( $s, $protocol, $autonumber ) {
                $unique = '4jzAfzB8hNvf4sqyO9Edd8pSmk9rE2in0Tgw3';
+
+               # URL character class
                $uc = "A-Za-z0-9_\\/~%\\-+&*#?!=()@\\x80-\\xFF";
 
                # this is  the list of separators that should be ignored if they
@@ -1069,42 +1073,53 @@ class Parser
                # in this case, the last comma should not become part of the URL,
                # but in "www.foo.com/123,2342,32.htm" it should.
                $sep = ",;\.:";
+
+               # File name character class, used for identifying images
                $fnc = 'A-Za-z0-9_.,~%\\-+&;#*?!=()@\\x80-\\xFF';
+               # Recognised image extensions
                $images = 'gif|png|jpg|jpeg';
 
                # PLEASE NOTE: The curly braces { } are not part of the regex,
                # they are interpreted as part of the string (used to tell PHP
                # that the content of the string should be inserted there).
-               $e1 = "/(^|[^\\[])({$protocol}:)([{$uc}{$sep}]+)\\/([{$fnc}]+)\\." .
+
+               # Regexp for matching image URLs
+               $rxImageURL = "/(^|[^\\[])({$protocol}:)([{$uc}{$sep}]+)\\/([{$fnc}]+)\\." .
                  "((?i){$images})([^{$uc}]|$)/";
 
-               $e2 = "/(^|[^\\[])({$protocol}:)(([".$uc."]|[".$sep."][".$uc."])+)([^". $uc . $sep. "]|[".$sep."]|$)/";
+               # Regexp for matching non-delimited URLs 
+               $rxFreeURL = "/(^|[^\\[])({$protocol}:)(([".$uc."]|[".$sep."][".$uc."])+)([^". $uc . $sep. "]|[".$sep."]|$)/";
                $sk =& $this->mOptions->getSkin();
 
-               if ( $autonumber and $this->mOptions->getAllowExternalImages() ) { # Use img tags only for HTTP urls
-                       $s = preg_replace( $e1, '\\1' . $sk->makeImage( "{$unique}:\\3" .
+               # Replace image URLs with <img> tags, but only for HTTP and HTTPS ($autonumber=true)
+               if ( $autonumber and $this->mOptions->getAllowExternalImages() ) { 
+                       $s = preg_replace( $rxImageURL, '\\1' . $sk->makeImage( "{$unique}:\\3" .
                          '/\\4.\\5', '\\4.\\5' ) . '\\6', $s );
                }
-               $s = preg_replace( $e2, '\\1' . "<a href=\"{$unique}:\\3\"" .
+
+               # Replace free URLs
+               $s = preg_replace( $rxFreeURL, '\\1' . "<a href=\"{$unique}:\\3\"" .
                  $sk->getExternalLinkAttributes( "{$unique}:\\3", wfEscapeHTML(
                  "{$unique}:\\3" ) ) . ">" . wfEscapeHTML( "{$unique}:\\3" ) .
                  '</a>\\5', $s );
                $s = str_replace( $unique, $protocol, $s );
 
+               # Search for external links with square brackets by splitting with explode()
                $a = explode( "[{$protocol}:", " " . $s );
                $s = array_shift( $a );
                $s = substr( $s, 1 );
 
                # Regexp for URL in square brackets
-               $e1 = "/^([{$uc}{$sep}]+)\\](.*)\$/sD";
+               $rxWithoutText = "/^([{$uc}{$sep}]+)\\](.*)\$/sD";
                # Regexp for URL with link text in square brackets
-               $e2 = "/^([{$uc}{$sep}]+)\\s+([^\\]]+)\\](.*)\$/sD";
+               $rxWithText = "/^([{$uc}{$sep}]+)\\s+([^\\]]+)\\](.*)\$/sD";
 
+               # Now interpret each instance of [protocol:
                foreach ( $a as $line ) {
 
                        # CASE 1: Link in square brackets, e.g.
                        # some text [http://domain.tld/some.link] more text
-                       if ( preg_match( $e1, $line, $m ) ) {
+                       if ( preg_match( $rxWithoutText, $line, $m ) ) {
                                $link = "{$protocol}:{$m[1]}";
                                $trail = $m[2];
                                if ( $autonumber ) { $text = "[" . ++$this->mAutonumber . "]"; }
@@ -1113,7 +1128,7 @@ class Parser
 
                        # CASE 2: Link with link text and text directly following it, e.g.
                        # This is a collection of [http://domain.tld/some.link link]s
-                       else if ( preg_match( $e2, $line, $m ) ) {
+                       else if ( preg_match( $rxWithText, $line, $m ) ) {
                                $link = "{$protocol}:{$m[1]}";
                                $text = $m[2];
                                $dtrail = '';