Desktop: Improve search keyword highlighting

ReactNativeClient/lib/string-utils-common.js

@@ -0,0 +1,55 @@
+function pregQuote(str, delimiter = '') {
+	return (str + '').replace(new RegExp('[.\\\\+*?\\[\\^\\]$(){}=!<>|:\\' + (delimiter || '') + '-]', 'g'), '\\$&');
+}
+
+function replaceRegexDiacritics(regexString) {
+	if (!regexString) return '';
+
+	const diacriticReplacements = {
+		'a': '[aàáâãäåāą]',
+		'A': '[AÀÁÂÃÄÅĀĄ]',
+		'c': '[cçćč]',
+		'C': '[CÇĆČ]',
+		'd': '[dđď]',
+		'D': '[DĐĎ]',
+		'e': '[eèéêëěēę]',
+		'E': '[EÈÉÊËĚĒĘ]',
+		'i': '[iìíîïī]',
+		'I': '[IÌÍÎÏĪ]',
+		'l': '[lł]',
+		'L': '[LŁ]',
+		'n': '[nñňń]',
+		'N': '[NÑŇŃ]',
+		'o': '[oòóôõöøō]',
+		'O': '[OÒÓÔÕÖØŌ]',
+		'r': '[rř]',
+		'R': '[RŘ]',
+		's': '[sšś]',
+		'S': '[SŠŚ]',
+		't': '[tť]',
+		'T': '[TŤ]',
+		'u': '[uùúûüůū]',
+		'U': '[UÙÚÛÜŮŪ]',
+		'y': '[yÿý]',
+		'Y': '[YŸÝ]',
+		'z': '[zžżź]',
+		'Z': '[ZŽŻŹ]',
+	};
+
+	let output = '';
+	for (let i = 0; i < regexString.length; i++) {
+		let c = regexString[i];
+		const r = diacriticReplacements[c];
+		if (r) {
+			output += r;
+		} else {
+			output += c;
+		}
+	}
+
+	return output;
+}
+
+if (typeof module !== 'undefined') {
+	module.exports = { pregQuote, replaceRegexDiacritics };
+}