feat: language support via locale config (#96)

Co-authored-by: hiroki osame <hiroki.osame@gmail.com>

src/utils/config.ts

@@ -26,6 +26,12 @@ const configParsers = {
 
 		return key;
 	},
+	locale(key: string) {
+		parseAssert('locale', key, 'Cannot be empty');
+		parseAssert('locale', /^[a-z-]+$/i.test(key), 'Must be a valid locale (letters and dashes/underscores). You can consult the list of codes in: https://wikipedia.org/wiki/List_of_ISO_639-1_codes');
+
+		return key;
+	},
 	generate(key: string) {
 		parseAssert('generate', key, 'Cannot be empty');
 		parseAssert('generate', /^\d+$/.test(key), 'Must be an integer');

src/utils/openai.ts

@@ -58,17 +58,18 @@ const sanitizeMessage = (message: string) => message.trim().replace(/[\n\r]/g, '
 
 const deduplicateMessages = (array: string[]) => Array.from(new Set(array));
 
-const promptTemplate = 'Write an insightful but concise Git commit message in a complete sentence in present tense for the following diff without prefacing it with anything:';
+const getPrompt = (locale: string, diff: string) => `Write an insightful but concise Git commit message in a complete sentence in present tense for the following diff without prefacing it with anything, the response must be in the language ${locale}:\n${diff}`;
 
 const model = 'text-davinci-003';
 const encoder = encodingForModel(model);
 
 export const generateCommitMessage = async (
 	apiKey: string,
+	locale: string,
 	diff: string,
 	completions: number,
 ) => {
-	const prompt = `${promptTemplate}\n${diff}`;
+	const prompt = getPrompt(locale, diff);
 
 	/**
 	 * text-davinci-003 has a token limit of 4000