<?php
session_start();
require_once 'db/config.php';
require_once 'auth-check.php';
require_once 'auth-helpers.php';

if (!can($_SESSION['user_role_id'], 'category', 'delete')) {
    header('Location: index.php?error=access_denied');
    exit;
}

$category_id = $_GET['id'] ?? null;

if (!$category_id) {
    header('Location: categories.php');
    exit;
}

try {
    $pdo = db();
    $pdo->beginTransaction();

    // Set category_id to NULL for assets associated with this category
    $stmt = $pdo->prepare('UPDATE assets SET category_id = NULL WHERE category_id = ?');
    $stmt->execute([$category_id]);

    // Delete the category
    $stmt = $pdo->prepare('DELETE FROM categories WHERE id = ?');
    $stmt->execute([$category_id]);

    $pdo->commit();

    header("Location: categories.php?success=category_deleted");
    exit;

} catch (PDOException $e) {
    if ($pdo->inTransaction()) {
        $pdo->rollBack();
    }
    // In a real app, log this error.
    header("Location: categories.php?error=db_error");
    exit;
}