<?php
declare(strict_types=1);

/**
 * Database connection & schema management for SQLite
 */

function get_db(): PDO {
    static $pdo = null;
    if ($pdo !== null) {
        return $pdo;
    }

    $dbDir = __DIR__ . '/../db';
    if (!is_dir($dbDir)) {
        mkdir($dbDir, 0755, true);
    }

    $dbPath = $dbDir . '/fitz.sqlite';
    $isNew = !file_exists($dbPath);

    $pdo = new PDO('sqlite:' . $dbPath, null, null, [
        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        PDO::ATTR_TIMEOUT => 5
    ]);

    // Enable WAL mode for concurrency and performance
    $pdo->exec('PRAGMA journal_mode = WAL;');
    $pdo->exec('PRAGMA foreign_keys = ON;');

    // Initialize tables if needed
    init_db_schema($pdo);

    return $pdo;
}

function init_db_schema(PDO $pdo): void {
    $pdo->exec("
        CREATE TABLE IF NOT EXISTS users (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            username TEXT UNIQUE NOT NULL,
            password_hash TEXT NOT NULL,
            role TEXT NOT NULL DEFAULT 'admin',
            created_at DATETIME DEFAULT CURRENT_TIMESTAMP
        );

        CREATE TABLE IF NOT EXISTS announcements (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            is_active INTEGER NOT NULL DEFAULT 1,
            type TEXT NOT NULL DEFAULT 'holiday',
            headline TEXT NOT NULL,
            message TEXT NOT NULL,
            start_date TEXT NULL,
            end_date TEXT NULL,
            show_banner INTEGER NOT NULL DEFAULT 1,
            show_in_hours INTEGER NOT NULL DEFAULT 1,
            updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
        );

        CREATE TABLE IF NOT EXISTS menu_categories (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            name TEXT NOT NULL,
            description TEXT NULL,
            sort_order INTEGER NOT NULL DEFAULT 0,
            created_at DATETIME DEFAULT CURRENT_TIMESTAMP
        );

        CREATE TABLE IF NOT EXISTS menu_items (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            category_id INTEGER NOT NULL REFERENCES menu_categories(id) ON DELETE CASCADE,
            name TEXT NOT NULL,
            description TEXT NULL,
            price TEXT NOT NULL,
            badge TEXT NULL,
            is_available INTEGER NOT NULL DEFAULT 1,
            sort_order INTEGER NOT NULL DEFAULT 0,
            updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
        );
    ");

    // Seed default admin user if table is empty (username: admin / password: password)
    $stmt = $pdo->query("SELECT COUNT(*) as count FROM users");
    $userCount = $stmt->fetchColumn();
    if ($userCount == 0) {
        $defaultPassHash = password_hash('password', PASSWORD_DEFAULT);
        $insert = $pdo->prepare("INSERT INTO users (username, password_hash, role) VALUES (?, ?, 'admin')");
        $insert->execute(['admin', $defaultPassHash]);
    }
}