import { existsSync, readFileSync } from "node:fs";
import { homedir } from "node:os";
import { join } from "node:path";

export const CONFIG_DIR = join(homedir(), ".pi", "english-tutor");
const SETTINGS_PATH = join(CONFIG_DIR, "settings.json");

export interface EnglishTutorSettings {
	enabled: boolean;
	correctionProvider: string;
	correctionModel: string;
	logPath: string;
	/** Messages with fewer words than this are skipped without a correction call. */
	skipShortMessages: number;
}

export const DEFAULT_SETTINGS: EnglishTutorSettings = {
	enabled: true,
	correctionProvider: "openrouter",
	correctionModel: "anthropic/claude-haiku-4.5",
	logPath: join(CONFIG_DIR, "log.jsonl"),
	skipShortMessages: 4,
};

export function loadSettings(): EnglishTutorSettings {
	if (!existsSync(SETTINGS_PATH)) return DEFAULT_SETTINGS;
	try {
		const raw = JSON.parse(readFileSync(SETTINGS_PATH, "utf8"));
		return { ...DEFAULT_SETTINGS, ...raw };
	} catch {
		return DEFAULT_SETTINGS;
	}
}