<?php
declare(strict_types=1);

require_once __DIR__ . '/../db/config.php';

function h(string $value): string {
    return htmlspecialchars($value, ENT_QUOTES, 'UTF-8');
}

function ensure_schema(): void {
    $pdo = db();
    $pdo->exec(
        "CREATE TABLE IF NOT EXISTS movies (
            id INT AUTO_INCREMENT PRIMARY KEY,
            title VARCHAR(160) NOT NULL,
            genre VARCHAR(80) NOT NULL,
            duration_min INT NOT NULL,
            rating VARCHAR(10) NOT NULL,
            description TEXT NOT NULL,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
        ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4"
    );

    $pdo->exec(
        "CREATE TABLE IF NOT EXISTS shows (
            id INT AUTO_INCREMENT PRIMARY KEY,
            movie_id INT NOT NULL,
            screen VARCHAR(40) NOT NULL,
            show_time DATETIME NOT NULL,
            format_label VARCHAR(10) NOT NULL,
            price DECIMAL(8,2) NOT NULL DEFAULT 12.00,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (movie_id) REFERENCES movies(id)
        ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4"
    );

    $pdo->exec(
        "CREATE TABLE IF NOT EXISTS bookings (
            id INT AUTO_INCREMENT PRIMARY KEY,
            show_id INT NOT NULL,
            customer_name VARCHAR(120) NOT NULL,
            customer_email VARCHAR(160) NOT NULL,
            seats VARCHAR(120) NOT NULL,
            total_price DECIMAL(8,2) NOT NULL,
            booking_code VARCHAR(20) NOT NULL UNIQUE,
            status VARCHAR(20) NOT NULL DEFAULT 'booked',
            checked_in TINYINT(1) NOT NULL DEFAULT 0,
            checked_in_at DATETIME NULL,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (show_id) REFERENCES shows(id)
        ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4"
    );
}

function seed_data(): void {
    $pdo = db();
    $count = (int)$pdo->query("SELECT COUNT(*) FROM movies")->fetchColumn();
    if ($count > 0) {
        return;
    }

    $pdo->beginTransaction();
    $stmt = $pdo->prepare("INSERT INTO movies (title, genre, duration_min, rating, description) VALUES (?, ?, ?, ?, ?)");
    $stmt->execute([
        'Midnight Signal',
        'Sci-Fi Thriller',
        124,
        'PG-13',
        'A space relay operator uncovers a message that redefines humanity’s future.'
    ]);
    $stmt->execute([
        'Velvet Avenue',
        'Drama',
        108,
        'PG',
        'A fashion editor returns home to rebuild her family studio and identity.'
    ]);

    $movies = $pdo->query("SELECT id, title FROM movies")->fetchAll();
    $now = new DateTimeImmutable('now');
    $showStmt = $pdo->prepare("INSERT INTO shows (movie_id, screen, show_time, format_label, price) VALUES (?, ?, ?, ?, ?)");
    foreach ($movies as $index => $movie) {
        $base = $now->modify('+' . ($index * 2 + 1) . ' hours');
        $showStmt->execute([$movie['id'], 'Screen A', $base->format('Y-m-d H:i:s'), '2D', 11.50]);
        $showStmt->execute([$movie['id'], 'Screen B', $base->modify('+3 hours')->format('Y-m-d H:i:s'), 'IMAX', 15.00]);
    }
    $pdo->commit();
}

function fetch_movies_with_shows(): array {
    $pdo = db();
    $movies = $pdo->query("SELECT * FROM movies ORDER BY created_at DESC")->fetchAll();
    $shows = $pdo->query(
        "SELECT s.*, m.title AS movie_title
         FROM shows s
         JOIN movies m ON m.id = s.movie_id
         ORDER BY s.show_time ASC"
    )->fetchAll();

    $grouped = [];
    foreach ($shows as $show) {
        $grouped[$show['movie_id']][] = $show;
    }

    return [$movies, $grouped];
}

function fetch_show(int $showId): ?array {
    $pdo = db();
    $stmt = $pdo->prepare(
        "SELECT s.*, m.title, m.genre, m.duration_min, m.rating, m.description
         FROM shows s
         JOIN movies m ON m.id = s.movie_id
         WHERE s.id = ?"
    );
    $stmt->execute([$showId]);
    $row = $stmt->fetch();
    return $row ?: null;
}

function fetch_booked_seats(int $showId): array {
    $pdo = db();
    $stmt = $pdo->prepare("SELECT seats FROM bookings WHERE show_id = ? AND status = 'booked'");
    $stmt->execute([$showId]);
    $booked = [];
    foreach ($stmt->fetchAll() as $row) {
        $parts = array_filter(array_map('trim', explode(',', $row['seats'])));
        foreach ($parts as $seat) {
            $booked[$seat] = true;
        }
    }
    return array_keys($booked);
}

function generate_booking_code(PDO $pdo): string {
    do {
        $code = strtoupper(bin2hex(random_bytes(3)));
        $stmt = $pdo->prepare("SELECT COUNT(*) FROM bookings WHERE booking_code = ?");
        $stmt->execute([$code]);
    } while ((int)$stmt->fetchColumn() > 0);
    return $code;
}

ensure_schema();
seed_data();