<?php
// db/migrate.php - Run pending migrations

// Ensure we are in the correct directory context if run from CLI
if (php_sapi_name() === 'cli' && !defined('DB_HOST')) {
    require_once __DIR__ . '/config.php';
} elseif (!defined('DB_HOST') && file_exists(__DIR__ . '/config.php')) {
    require_once __DIR__ . '/config.php';
}

function run_migrations() {
    $pdo = db();
    $messages = [];

    // 1. Create migrations table if not exists
    try {
        $pdo->exec(
            "\n            CREATE TABLE IF NOT EXISTS migrations (\n                id INT AUTO_INCREMENT PRIMARY KEY,\n                migration_name VARCHAR(255) NOT NULL UNIQUE,\n                executed_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP\n            ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;\n        "
        );
    } catch (PDOException $e) {
        return ["Error creating migrations table: " . $e->getMessage()];
    }

    // 2. Get executed migrations
    $executed = [];
    try {
        $stmt = $pdo->query("SELECT migration_name FROM migrations");
        while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
            $executed[] = $row['migration_name'];
        }
    } catch (PDOException $e) {
        return ["Error fetching executed migrations: " . $e->getMessage()];
    }

    // 3. Scan for migration files
    $migrationFiles = glob(__DIR__ . '/migrations/*.php');
    if ($migrationFiles === false) {
        return ["Error scanning migration directory."];
    }
    
    // Sort files to ensure order (by name usually works if named correctly)
    sort($migrationFiles);

    $count = 0;
    foreach ($migrationFiles as $file) {
        $filename = basename($file);
        
        if (in_array($filename, $executed)) {
            continue;
        }

        // Run migration
        try {
            // We use output buffering to capture echo output from migration files
            ob_start();
            // Include inside a closure/function scope to avoid variable collisions
            // but we need to ensure $pdo is available if they use it.
            // Most files do: require config.php; $pdo = db();
            // Since we already required config.php, require_once will skip it.
            // So they will just get $pdo = db(); which works.
            include $file;
            $output = ob_get_clean();
            
            // Log success
            $messages[] = "Executed $filename: " . trim($output);
            
            // Record in DB
            $stmt = $pdo->prepare("INSERT INTO migrations (migration_name) VALUES (?)");
            $stmt->execute([$filename]);
            $count++;
            
        } catch (Throwable $e) {
            ob_end_clean(); // Clean buffer if error
            $messages[] = "Failed to execute $filename: " . $e->getMessage();
            return $messages; // Stop on error
        }
    }

    if ($count === 0) {
        $messages[] = "No new migrations to run.";
    } else {
        $messages[] = "Successfully ran $count migrations.";
    }
    
    return $messages;
}

// If run directly from CLI
if (php_sapi_name() === 'cli' && basename(__FILE__) == basename($_SERVER['SCRIPT_FILENAME'])) {
    $results = run_migrations();
    echo implode("\n", $results) . "\n";
}