1 files changed, 151 insertions, 0 deletions
diff --git a/www/wiki/extensions/UploadWizard/resources/mw.Escaper.js b/www/wiki/extensions/UploadWizard/resources/mw.Escaper.js
new file mode 100644
index 00000000..e57d42af
--- /dev/null
+++ b/www/wiki/extensions/UploadWizard/resources/mw.Escaper.js
@@ -0,0 +1,151 @@
+( function ( mw, OO ) {
+	mw.Escaper = {
+		/**
+		 * Escapes wikitext for use inside {{templates}}.
+		 *
+		 * @param {string} wikitext
+		 * @return {string}
+		 */
+		escapeForTemplate: function ( wikitext ) {
+			return this.escapePipes( wikitext );
+		},
+
+		/**
+		 * Escapes pipe characters, which could be problematic when the content is
+		 * inserted in a template.
+		 *
+		 * @param {string} wikitext
+		 * @return {string}
+		 */
+		escapePipes: function ( wikitext ) {
+			var extractedTemplates, extractedLinks;
+
+			// Pipes (`|`) must be escaped because we'll be inserting this
+			// content into a templates & pipes would mess up the syntax.
+			// First, urlencode pipes inside links:
+			wikitext = wikitext.replace( /\bhttps?:\/\/[^\s]+/g, function ( match ) {
+				return match.replace( /\|/g, '%7C' );
+			} );
+
+			// Second, pipes can be valid inside other templates or links in
+			// wikitext, so we'll first extract those from the content, then
+			// replace the pipes, then restore the original (extracted) content:
+			extractedTemplates = this.extractTemplates( wikitext );
+			extractedLinks = this.extractLinks( extractedTemplates[ 0 ] );
+			wikitext = extractedLinks[ 0 ].replace( /\|/g, '{{!}}' );
+			return this.restoreExtracts( wikitext, $.extend( extractedTemplates[ 1 ], extractedLinks[ 1 ] ) );
+		},
+
+		/**
+		 * Extract all {{templates}} from wikitext, replacing them with
+		 * placeholder content in the form of {{1}}, {{2}}.
+		 *
+		 * Nested templates will safely be extracted by first replacing inner
+		 * templates, then moving outwards, ensuring we don't get closing
+		 * bracket mismatches.
+		 *
+		 * Restoring the content is as simple as feeding the returned content &
+		 * replacements back into this.restoreExtracts.
+		 *
+		 * @param {string} wikitext
+		 * @return {array} [{string} wikitext, {Object} replacements]
+		 */
+		extractTemplates: function ( wikitext ) {
+			var extracts = {},
+				previousExtracts = {},
+				extracted = wikitext,
+				// the regex explained:
+				// * `[^\{]`: character can not be {
+				// * `\{(?!\{)`: or if it is, it can't be followed by another {
+				// this excludes template opening brackets: {{
+				// * `\{\{[0-9]+\}\}`: unless it's a complete {{[0-9]+}}
+				//   sequence, generated by an earlier run of this regex
+				regex = /\{\{([^{]|\{(?!\{)|\{\{[0-9]+\}\})*?\}\}/g,
+				callback = function ( match ) {
+					var replacement = '{{' + Object.keys( extracts ).length + '}}';
+
+					// safeguard for not replacing already-replaced matches
+					// this makes sure that when real content contains something
+					// like {{1}}, it will still be replaced, while {{1}}
+					// generated by this code can be recognized & ignored
+					if ( match in previousExtracts ) {
+						return match;
+					}
+
+					extracts[ replacement ] = match;
+					return replacement;
+				};
+
+			do {
+				wikitext = extracted;
+				previousExtracts = OO.copy( extracts );
+				extracted = wikitext.replace( regex, callback );
+			} while ( wikitext !== extracted );
+
+			return [ wikitext, extracts ];
+		},
+
+		/**
+		 * Extract all [[links]] from wikitext, replacing them with placeholder
+		 * content in the form of [[1]], [[2]].
+		 *
+		 * Restoring the content is as simple as feeding the returned content &
+		 * replacements back into this.restoreExtracts.
+		 *
+		 * @param {string} wikitext
+		 * @return {array} [{string} wikitext, {Object} replacements]
+		 */
+		extractLinks: function ( wikitext ) {
+			var extracts = {};
+
+			wikitext = wikitext.replace( /\[\[.*?\]\]/g, function ( match ) {
+				var replacement = '[[' + Object.keys( extracts ).length + ']]';
+				extracts[ replacement ] = match;
+				return replacement;
+			} );
+
+			return [ wikitext, extracts ];
+		},
+
+		/**
+		 * Restores content that was extracted from wikitext.
+		 *
+		 * @param {string} wikitext
+		 * @param {Object} replacements
+		 * @return {string}
+		 */
+		restoreExtracts: function ( wikitext, replacements ) {
+			// turn search keys into a regular expression, allowing us to match
+			// all of them at once
+			var searchValues = Object.keys( replacements ).map( mw.RegExp.escape ),
+				searchRegex = new RegExp( '(' + searchValues.join( '|' ) + ')', 'g' ),
+				callback = function ( match ) {
+					var replacement = replacements[ match ];
+
+					// we matched something that has no replacement, must be valid
+					// user input that just happens to look like on of the
+					// replacement values
+					if ( replacement === undefined ) {
+						return match;
+					}
+
+					// if we find the replacement itself matches a search value, we
+					// also don't want to go recursive: nesting doesn't work like
+					// that, it's just a coincidence where user input happens to
+					// look just like a replacement value (e.g. `{{1}}`)
+					if ( replacement in replacements ) {
+						return replacement;
+					}
+
+					// we must not replace this one again, to avoid getting stuck in
+					// endless recursion
+					delete replacements[ match ];
+
+					// go recursive, there may be more replacements nested down there
+					return this.restoreExtracts( replacement, replacements );
+				}.bind( this );
+
+			return wikitext.replace( searchRegex, callback );
+		}
+	};
+}( mediaWiki, OO ) );