<?php
session_start();

$config_file = __DIR__ . '/db/config.php';
$step = isset($_GET['step']) ? (int)$_GET['step'] : 1;

// If config exists and we are at step 1, we might want to skip to step 2
if (file_exists($config_file) && $step === 1) {
    $step = 2;
}

$error = '';
$success = '';

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    if ($step === 1) {
        $host = $_POST['db_host'] ?? '';
        $name = $_POST['db_name'] ?? '';
        $user = $_POST['db_user'] ?? '';
        $pass = $_POST['db_pass'] ?? '';

        try {
            $pdo = new PDO("mysql:host=$host", $user, $pass);
            $pdo->exec("CREATE DATABASE IF NOT EXISTS `$name` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
            $pdo = new PDO("mysql:host=$host;dbname=$name", $user, $pass);
            
            $config_content = "<?php
define('DB_HOST', '$host');
define('DB_NAME', '$name');
define('DB_USER', '$user');
define('DB_PASS', '$pass');

function db() {
    static \$pdo;
    if (!\$pdo) {
        \$pdo = new PDO('mysql:host='.DB_HOST.';dbname='.DB_NAME.';charset=utf8mb4', DB_USER, DB_PASS, [
            PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
            PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        ]);
    }
    return \$pdo;
}

require_once __DIR__ . '/../includes/functions.php';
";
            file_put_contents($config_file, $config_content);
            header("Location: install.php?step=2");
            exit;
        } catch (Exception $e) {
            $error = "Database Connection Failed: " . $e->getMessage();
        }
    } elseif ($step === 2) {
        require_once $config_file;
        try {
            $pdo = db();
            
            // 1. Run Base Schema
            $schema = file_get_contents(__DIR__ . '/db/schema.sql');
            // Split schema by ; to execute one by one to avoid issues with some PDO drivers
            // But usually PDO::exec handles multiple if allowed. 
            // Better to use a simpler approach for schema.sql
            $pdo->exec($schema);
            
            // 2. Create migrations table if not exists
            $pdo->exec("CREATE TABLE IF NOT EXISTS migrations (
                id INT AUTO_INCREMENT PRIMARY KEY,
                migration VARCHAR(255) UNIQUE NOT NULL,
                applied_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
            )");

            // 3. Run Migrations
            $migrations_dir = __DIR__ . '/db/migrations/';
            $migrations = glob($migrations_dir . '*.sql');
            sort($migrations);
            
            // Get applied migrations
            $stmt = $pdo->query("SELECT migration FROM migrations");
            $applied = $stmt->fetchAll(PDO::FETCH_COLUMN);

            foreach ($migrations as $migration_path) {
                $migration_name = basename($migration_path);
                if (!in_array($migration_name, $applied)) {
                    $sql = file_get_contents($migration_path);
                    if (!empty(trim($sql))) {
                        // Some migrations might fail because they were partially applied before we had tracking
                        // We will wrap each in a try-catch or just execute and catch specific duplicate column errors
                        try {
                            $pdo->exec($sql);
                            $stmt = $pdo->prepare("INSERT INTO migrations (migration) VALUES (?)");
                            $stmt->execute([$migration_name]);
                        } catch (PDOException $e) {
                            // If it's "Duplicate column name" or "Duplicate key name", we might want to skip and mark as applied
                            // to recover from a broken state
                            if (strpos($e->getMessage(), 'Duplicate column name') !== false || 
                                strpos($e->getMessage(), 'Duplicate key name') !== false ||
                                strpos($e->getMessage(), 'already exists') !== false) {
                                $stmt = $pdo->prepare("INSERT INTO migrations (migration) VALUES (?)");
                                $stmt->execute([$migration_name]);
                            } else {
                                throw $e;
                            }
                        }
                    }
                }
            }
            
            // 4. Seed initial data (from init.php logic)
            $stmt = $pdo->query("SELECT COUNT(*) FROM outlets");
            if ($stmt->fetchColumn() == 0) {
                $pdo->exec("INSERT INTO outlets (name, address) VALUES ('Main Downtown', '123 Main St'), ('Westside Hub', '456 West Blvd')");
                $pdo->exec("INSERT INTO categories (name, sort_order) VALUES ('Burgers', 1), ('Sides', 2), ('Drinks', 3)");
                $pdo->exec("INSERT INTO products (category_id, name, description, price) VALUES 
                    (1, 'Signature Burger', 'Juicy beef patty with special sauce', 12.99),
                    (1, 'Veggie Delight', 'Plant-based patty with fresh avocado', 11.50),
                    (2, 'Truffle Fries', 'Crispy fries with truffle oil and parmesan', 5.99),
                    (3, 'Craft Cola', 'House-made sparkling cola', 3.50)");
            }

            header("Location: install.php?step=3");
            exit;
        } catch (Exception $e) {
            $error = "Initialization Failed: " . $e->getMessage();
        }
    } elseif ($step === 3) {
        require_once $config_file;
        $username = $_POST['admin_user'] ?? '';
        $password = $_POST['admin_pass'] ?? '';
        $email = $_POST['admin_email'] ?? '';

        if (empty($username) || empty($password)) {
            $error = "Username and Password are required.";
        } else {
            try {
                $pdo = db();
                $hashed_pass = password_hash($password, PASSWORD_DEFAULT);
                
                // Ensure Admin group exists
                $stmt = $pdo->prepare("SELECT id FROM user_groups WHERE name = 'Administrator' LIMIT 1");
                $stmt->execute();
                $group_id = $stmt->fetchColumn();

                if (!$group_id) {
                    $pdo->exec("INSERT INTO user_groups (name, permissions) VALUES ('Administrator', 'all')");
                    $group_id = $pdo->lastInsertId();
                }

                $stmt = $pdo->prepare("SELECT id FROM users WHERE username = ?");
                $stmt->execute([$username]);
                if ($stmt->fetch()) {
                    // Admin already exists, just move to next step
                    header("Location: install.php?step=4");
                    exit;
                }

                $stmt = $pdo->prepare("INSERT INTO users (group_id, username, password, full_name, email, is_active) VALUES (?, ?, ?, ?, ?, 1)");
                $stmt->execute([$group_id, $username, $hashed_pass, 'Super Admin', $email]);
                
                header("Location: install.php?step=4");
                exit;
            } catch (Exception $e) {
                $error = "Failed to create Admin: " . $e->getMessage();
            }
        }
    }
}

?>
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>POS System Installation</title>
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css" rel="stylesheet">
    <style>
        body { background-color: #f8f9fa; }
        .install-card { max-width: 600px; margin: 50px auto; border-radius: 15px; box-shadow: 0 10px 30px rgba(0,0,0,0.1); }
        .step-indicator { display: flex; justify-content: space-between; margin-bottom: 30px; }
        .step { width: 30px; height: 30px; border-radius: 50%; background: #dee2e6; display: flex; align-items: center; justify-content: center; font-weight: bold; }
        .step.active { background: #0d6efd; color: white; }
        .step.completed { background: #198754; color: white; }
    </style>
</head>
<body>
    <div class="container">
        <div class="card install-card">
            <div class="card-body p-5">
                <h2 class="text-center mb-4">Installation</h2>
                
                <div class="step-indicator">
                    <div class="step <?= $step >= 1 ? ($step > 1 ? 'completed' : 'active') : '' ?>">1</div>
                    <div class="step <?= $step >= 2 ? ($step > 2 ? 'completed' : 'active') : '' ?>">2</div>
                    <div class="step <?= $step >= 3 ? ($step > 3 ? 'completed' : 'active') : '' ?>">3</div>
                    <div class="step <?= $step >= 4 ? ($step > 4 ? 'completed' : 'active') : '' ?>">4</div>
                </div>

                <?php if ($error): ?>
                    <div class="alert alert-danger"><?= $error ?></div>
                <?php endif; ?>

                <?php if ($step === 1): ?>
                    <h4>Step 1: Database Configuration</h4>
                    <p class="text-muted">Enter your database connection details.</p>
                    <form method="POST">
                        <div class="mb-3">
                            <label class="form-label">DB Host</label>
                            <input type="text" name="db_host" class="form-control" value="localhost" required>
                        </div>
                        <div class="mb-3">
                            <label class="form-label">DB Name</label>
                            <input type="text" name="db_name" class="form-control" placeholder="pos_system" required>
                        </div>
                        <div class="mb-3">
                            <label class="form-label">DB User</label>
                            <input type="text" name="db_user" class="form-control" required>
                        </div>
                        <div class="mb-3">
                            <label class="form-label">DB Password</label>
                            <input type="password" name="db_pass" class="form-control">
                        </div>
                        <button type="submit" class="btn btn-primary w-100">Test Connection & Save</button>
                    </form>

                <?php elseif ($step === 2): ?>
                    <h4>Step 2: Initialize Database</h4>
                    <p>Ready to create tables and run migrations. This will set up the latest database structure.</p>
                    <form method="POST">
                        <button type="submit" class="btn btn-primary w-100">Run Database Setup</button>
                    </form>

                <?php elseif ($step === 3): ?>
                    <h4>Step 3: Create Super Admin</h4>
                    <p class="text-muted">Create your first administrator account.</p>
                    <form method="POST">
                        <div class="mb-3">
                            <label class="form-label">Username</label>
                            <input type="text" name="admin_user" class="form-control" value="admin" required>
                        </div>
                        <div class="mb-3">
                            <label class="form-label">Email</label>
                            <input type="email" name="admin_email" class="form-control" placeholder="admin@example.com" required>
                        </div>
                        <div class="mb-3">
                            <label class="form-label">Password</label>
                            <input type="password" name="admin_pass" class="form-control" required>
                        </div>
                        <button type="submit" class="btn btn-primary w-100">Create Admin Account</button>
                    </form>

                <?php elseif ($step === 4): ?>
                    <div class="text-center">
                        <div class="text-success mb-4">
                            <svg xmlns="http://www.w3.org/2000/svg" width="64" height="64" fill="currentColor" class="bi bi-check-circle-fill" viewBox="0 0 16 16">
                                <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zm-3.97-3.03a.75.75 0 0 0-1.08.022L7.477 9.417 5.384 7.323a.75.75 0 0 0-1.06 1.06L6.97 11.03a.75.75 0 0 0 1.079-.02l3.992-4.99a.75.75 0 0 0-.01-1.05z"/>
                            </svg>
                        </div>
                        <h4>Installation Complete!</h4>
                        <p>The system has been successfully installed.</p>
                        <div class="alert alert-warning mt-3">
                            <strong>Security Warning:</strong> Please delete the <code>install.php</code> file from your server immediately!
                        </div>
                        <a href="login.php" class="btn btn-primary mt-3">Go to Login</a>
                    </div>
                <?php endif; ?>
            </div>
        </div>
    </div>
</body>
</html>