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

const DB_PATH = process.env.DB_PATH || '/data/db/app.db';

fs.mkdirSync(path.dirname(DB_PATH), { recursive: true });

const db = new Database(DB_PATH);
db.pragma('journal_mode = WAL');
db.pragma('foreign_keys = ON');

db.exec(`
  CREATE TABLE IF NOT EXISTS customers (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    name TEXT NOT NULL,
    slug TEXT NOT NULL UNIQUE,
    token TEXT NOT NULL UNIQUE,
    password_hash TEXT,
    expires_at INTEGER,
    created_at INTEGER NOT NULL
  );

  CREATE TABLE IF NOT EXISTS uploads (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    customer_id INTEGER NOT NULL,
    filename TEXT NOT NULL,
    relative_path TEXT NOT NULL,
    size INTEGER NOT NULL,
    uploaded_at INTEGER NOT NULL,
    FOREIGN KEY(customer_id) REFERENCES customers(id) ON DELETE CASCADE
  );

  CREATE TABLE IF NOT EXISTS users (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    username TEXT NOT NULL UNIQUE,
    password_hash TEXT NOT NULL,
    role TEXT NOT NULL DEFAULT 'staff',
    created_at INTEGER NOT NULL
  );

  CREATE TABLE IF NOT EXISTS sessions (
    token TEXT PRIMARY KEY,
    user_id INTEGER NOT NULL,
    created_at INTEGER NOT NULL,
    expires_at INTEGER NOT NULL,
    FOREIGN KEY(user_id) REFERENCES users(id) ON DELETE CASCADE
  );

  CREATE TABLE IF NOT EXISTS customer_access (
    customer_id INTEGER NOT NULL,
    user_id INTEGER NOT NULL,
    access TEXT NOT NULL DEFAULT 'read',
    PRIMARY KEY(customer_id, user_id),
    FOREIGN KEY(customer_id) REFERENCES customers(id) ON DELETE CASCADE,
    FOREIGN KEY(user_id) REFERENCES users(id) ON DELETE CASCADE
  );

  CREATE TABLE IF NOT EXISTS settings (
    key TEXT PRIMARY KEY,
    value TEXT
  );
`);

// Additive migrations for existing DBs
function addColumnIfMissing(table, column, ddl) {
  const cols = db.prepare(`PRAGMA table_info(${table})`).all();
  if (!cols.some(c => c.name === column)) {
    db.exec(`ALTER TABLE ${table} ADD COLUMN ${column} ${ddl}`);
  }
}
addColumnIfMissing('users', 'email', 'TEXT');
addColumnIfMissing('customers', 'email', 'TEXT');
addColumnIfMissing('customers', 'archived_at', 'INTEGER');

module.exports = db;