const Database = require('better-sqlite3');
const path = require('path');
const fs = require('fs');

const dataDir = '/app/data';
if (!fs.existsSync(dataDir)) {
  fs.mkdirSync(dataDir, { recursive: true });
}

const dbPath = path.join(dataDir, 'xiaocai.db');
const db = new Database(dbPath);

// 关键 pragma
db.pragma('journal_mode = WAL');
db.pragma('foreign_keys = ON');

// 创建基础表
db.exec(`
  CREATE TABLE IF NOT EXISTS users (
    username TEXT PRIMARY KEY,
    password TEXT NOT NULL,
    is_admin INTEGER DEFAULT 0
  );

  CREATE TABLE IF NOT EXISTS rooms (
    id TEXT PRIMARY KEY,
    name TEXT NOT NULL,
    created_by TEXT NOT NULL,
    white_list TEXT DEFAULT '',
    created_at TEXT DEFAULT (datetime('now','localtime'))
  );

  CREATE TABLE IF NOT EXISTS messages (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    room_id TEXT NOT NULL,
    user TEXT NOT NULL,
    text TEXT,
    attachments TEXT,
    timestamp TEXT DEFAULT (datetime('now','localtime')),
    FOREIGN KEY(room_id) REFERENCES rooms(id)
  );

  CREATE TABLE IF NOT EXISTS purchases (
    id TEXT PRIMARY KEY,
    room_id TEXT NOT NULL,
    item TEXT,
    quantity INTEGER DEFAULT 1,
    unit_price REAL DEFAULT 0,
    amount REAL DEFAULT 0,
    freight REAL DEFAULT 0,
    payment_method TEXT DEFAULT '未指定',
    invoice_type TEXT DEFAULT '无票',
    status TEXT DEFAULT '待付款',
    applicant TEXT,
    remarks TEXT DEFAULT '',
    created_at TEXT DEFAULT (datetime('now','localtime')),
    updated_at TEXT DEFAULT (datetime('now','localtime')),
    FOREIGN KEY(room_id) REFERENCES rooms(id)
  );

  CREATE TABLE IF NOT EXISTS purchase_history (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    purchase_id TEXT NOT NULL,
    action TEXT NOT NULL,
    user TEXT NOT NULL,
    timestamp TEXT DEFAULT (datetime('now','localtime')),
    attachments TEXT,
    FOREIGN KEY(purchase_id) REFERENCES purchases(id)
  );

  CREATE TABLE IF NOT EXISTS purchase_attachments (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    purchase_id TEXT NOT NULL,
    file_path TEXT NOT NULL,
    uploaded_by TEXT NOT NULL,
    timestamp TEXT DEFAULT (datetime('now','localtime')),
    FOREIGN KEY(purchase_id) REFERENCES purchases(id)
  );
`);

// 安全迁移（忽略已存在的列）
const migrations = [
  `ALTER TABLE purchases ADD COLUMN quantity INTEGER DEFAULT 1`,
  `ALTER TABLE purchases ADD COLUMN unit_price REAL DEFAULT 0`,
  `ALTER TABLE purchases ADD COLUMN freight REAL DEFAULT 0`,
  `ALTER TABLE purchases ADD COLUMN invoice_type TEXT DEFAULT '无票'`,
  `ALTER TABLE purchases ADD COLUMN payment_method TEXT DEFAULT '未指定'`,
  `ALTER TABLE purchases ADD COLUMN remarks TEXT DEFAULT ''`,
  `ALTER TABLE rooms ADD COLUMN white_list TEXT DEFAULT ''`,
];
for (const sql of migrations) {
  try { db.exec(sql); } catch (e) { /* 列已存在 */ }
}

// 统一存量状态值
try { db.exec("UPDATE purchases SET status = '待付款' WHERE status = '待处理'"); } catch (e) {}

module.exports = db;