source: Dev/branches/rest-dojo-ui/client/util/build/replace.js @ 256

define(["./fs"], function(fs) {
        var cached= {};

        return function(contents, replacement) {
                var encoding= "utf8";
                if (replacement instanceof Array) {
                        // replacement is a vector of replacement instructions; maybe the first item is an encoding
                        if (typeof replacement[0]=="string") {
                                encoding= replacement[0];
                                replacement= replacement.slice(1);
                        }
                } else {
                        // replacement is a single replacement [search, replacement, type] triple
                        replacement= [replacement];
                }
                // at this point, encoding has been determined and replacement is a vector of [search, replacement, type] triples

                replacement.forEach(function(item) {
                        var
                                searchText= item[0],
                                replacementText= item[1],
                                type= item[2];
                        if (type=="file") {
                                // replacementText gives a filename that holds the replacement text
                                // TODO add type AMD module
                                replacementText= (cached[filename]= cached[filename] || fs.readFileSynch(replacementText, encoding));
                        }
                        if (searchText instanceof RegExp) {
                                contents= contents.replace(searchText, replacementText);
                        } else if (typeof searchText=="function") {
                                contents= searchText(contents);
                        } else {
                                // replace all occurences of searchText with replacementText
                                var
                                        searchTextLength= searchText.length,
                                        replacementTextLength= replacementText.length,
                                        start= contents.indexOf(searchText);
                                while (start!=-1) {
                                        contents= contents.substring(0, start) + replacementText + contents.substring(start + searchTextLength);
                                        start= contents.indexOf(searchText, start + replacementTextLength);
                                }
                        }
                });
                return contents;
        };
});