feat: config command (#71)

src/utils/config.ts

@@ -0,0 +1,63 @@
+import fs from 'fs/promises';
+import path from 'path';
+import os from 'os';
+import ini from 'ini';
+
+const keyValidators = {
+	OPENAI_KEY(key: string) {
+		if (!key) {
+			return 'Cannot be empty';
+		}
+
+		if (!key.startsWith('sk-')) {
+			return 'Must start with "sk-"';
+		}
+
+		if (key.length !== 51) {
+			return 'Must be 51 characters long';
+		}
+	},
+} as const;
+
+type ValidKeys = keyof typeof keyValidators;
+type ConfigType = {
+	[key in ValidKeys]?: string;
+};
+
+const configPath = path.join(os.homedir(), '.aicommits');
+
+const fileExists = (filePath: string) => fs.access(filePath).then(() => true, () => false);
+
+export const getConfig = async (): Promise<ConfigType> => {
+	const configExists = await fileExists(configPath);
+	if (!configExists) {
+		return {};
+	}
+
+	const configString = await fs.readFile(configPath, 'utf8');
+	return ini.parse(configString);
+};
+
+const { hasOwnProperty } = Object.prototype;
+const hasOwn = (object: unknown, key: PropertyKey) => hasOwnProperty.call(object, key);
+
+export const setConfigs = async (
+	keyValues: [key: string, value: string][],
+) => {
+	const config = await getConfig();
+
+	for (const [key, value] of keyValues) {
+		if (!hasOwn(keyValidators, key)) {
+			throw new Error(`Invalid config property: ${key}`);
+		}
+
+		const isInvalid = keyValidators[key as ValidKeys](value);
+		if (isInvalid) {
+			throw new Error(`Invalid value for ${key}: ${isInvalid}`);
+		}
+
+		config[key as ValidKeys] = value;
+	}
+
+	await fs.writeFile(configPath, ini.stringify(config), 'utf8');
+};