import 'dotenv/config';
import express from 'express';
import cors from 'cors';
import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import { initDb, seedAdmin } from './db.js';
import { createAuthRouter } from './routes/auth.js';
import { createDecksRouter } from './routes/decks.js';
import { createAdminRouter } from './routes/admin.js';
import { createStatsRouter } from './routes/stats.js';

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const PORT = Number(process.env.PORT) || 3000;
const DB_PATH = process.env.DB_PATH || path.join(__dirname, '..', 'data', 'uadeck.db');

/**
 * package.json에서 서비스 버전을 읽는다. (실패 시 'unknown')
 * @returns {string}
 */
function readAppVersion() {
    try {
        const pkgRaw = fs.readFileSync(path.join(__dirname, '..', 'package.json'), 'utf-8');
        return JSON.parse(pkgRaw).version || 'unknown';
    } catch {
        return 'unknown';
    }
}

const APP_VERSION = readAppVersion();

if (!process.env.DATAS_PATH) {
    process.env.DATAS_PATH = path.join(__dirname, '..', '..', 'datas');
}

const db = initDb(DB_PATH);
seedAdmin(db);

const app = express();

// nginx 프록시 1홉 뒤에서 실행 → rate limit이 실제 클라이언트 IP(X-Forwarded-For)를 쓰도록
app.set('trust proxy', 1);

const corsOrigins = process.env.CORS_ORIGINS
    ? process.env.CORS_ORIGINS.split(',').map((o) => o.trim())
    : true;

app.use(cors({ origin: corsOrigins, credentials: true }));
app.use(express.json({ limit: '20mb' }));

app.get('/api/v1/health', (_req, res) => {
    res.json({ ok: true, version: APP_VERSION });
});

app.use('/api/stats', createStatsRouter(db, APP_VERSION));
app.use('/api/v1/stats', createStatsRouter(db, APP_VERSION));
app.use('/api/v1/auth', createAuthRouter(db));
app.use('/api/v1/decks', createDecksRouter(db));
app.use('/api/v1/admin', createAdminRouter(db));

app.use((err, _req, res, _next) => {
    if (err.type === 'entity.too.large') {
        return res.status(413).json({
            error: '요청 크기가 너무 큽니다. 고화질 옵션을 끄고 다시 저장해 주세요.',
        });
    }
    console.error(err);
    res.status(500).json({ error: '서버 오류가 발생했습니다.' });
});

app.listen(PORT, () => {
    console.log(`UNIARE API v${APP_VERSION} listening on :${PORT}`);
    console.log(`DB: ${DB_PATH}`);
    console.log(`DATAS: ${process.env.DATAS_PATH || '(default ../datas)'}`);
});