1 files changed, 49 insertions, 0 deletions
diff --git a/ext/js/language/text-processors.js b/ext/js/language/text-processors.js
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+++ b/ext/js/language/text-processors.js
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+/*
+ * Copyright (C) 2024  Yomitan Authors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/** @type {import('language').TextProcessorOptions<boolean>} */
+export const basicTextProcessorOptions = [false, true];
+
+/** @type {import('language').TextProcessor<boolean>} */
+export const decapitalize = {
+    name: 'Decapitalize text',
+    description: 'CAPITALIZED TEXT → capitalized text',
+    options: basicTextProcessorOptions,
+    process: (str, setting) => (setting ? str.toLowerCase() : str)
+};
+
+/** @type {import('language').TextProcessor<boolean>} */
+export const capitalizeFirstLetter = {
+    name: 'Capitalize first letter',
+    description: 'lowercase text → Lowercase text',
+    options: basicTextProcessorOptions,
+    process: (str, setting) => (setting ? str.charAt(0).toUpperCase() + str.slice(1) : str)
+};
+
+/**
+ * WARNING: This should NOT be used with languages that use Han characters,
+ *          as it can result in undesirable normalization:
+ *            - '\u9038'.normalize('NFD') => '\u9038' (逸)
+ *            - '\ufa67'.normalize('NFD') => '\u9038' (逸 => 逸)
+ * @type {import('language').TextProcessor<boolean>}
+ */
+export const removeAlphabeticDiacritics = {
+    name: 'Remove Alphabetic Diacritics',
+    description: 'ἄήé -> αηe',
+    options: basicTextProcessorOptions,
+    process: (str, setting) => (setting ? str.normalize('NFD').replace(/[\u0300-\u036f]/g, '') : str)
+};