<?php

require_once __DIR__ . '/../autoloader.php';


use BigDump\Configuration;
use BigDump\Database;
use BigDump\FileHandler;
use BigDump\Dumper;

// Basic error handling
ini_set('display_errors', 1);
error_reporting(E_ALL);

session_start();

// Load configuration
$config = new Configuration();

// Instantiate core classes
try {
    $db = new Database($config);
    $fileHandler = new FileHandler($config);
    $dumper = new Dumper($config, $db, $fileHandler);
} catch (\Exception $e) {
    die("Error during initialization: " . $e->getMessage());
}


// Simple router
$action = $_GET['action'] ?? 'start';

try {
    switch ($action) {
        case 'upload':
            if (isset($_FILES['dumpfile'])) {
                $fileHandler->handleUpload($_FILES['dumpfile']);
                $_SESSION['success'] = "File uploaded successfully.";
            }
            header('Location: .');
            exit;

        case 'delete':
            if (isset($_GET['file'])) {
                $fileHandler->deleteFile($_GET['file']);
                $_SESSION['success'] = "File deleted successfully.";
            }
            header('Location: .');
            exit;

        case 'import':
            $filename = $_GET['file'] ?? '';
            if (empty($filename)) {
                throw new \Exception("No file specified for import.");
            }

            $start_line = (int)($_GET['start_line'] ?? 1);
            $foffset = (int)($_GET['foffset'] ?? 0);
            $totalqueries = (int)($_GET['totalqueries'] ?? 0);
            $delimiter = $_GET['delimiter'] ?? null;

            if ($config->ajax) {
                // AJAX request
                if (isset($_GET['ajax_request'])) {
                    header('Content-Type: application/json');
                    $dumper->prepare($filename, $start_line, $foffset, $totalqueries, $delimiter);
                    $result = $dumper->run();
                    echo json_encode($result);
                    exit;
                }

                // Initial page for AJAX import
                $content = renderTemplate('import.php', [
                    'filename' => $filename,
                    'start_line' => $start_line,
                    'delaypersession' => $config->delaypersession,
                ]);
                echo renderTemplate('layout.php', ['content' => $content]);

            } else {
                // No-JS fallback
                $dumper->prepare($filename, $start_line, $foffset, $totalqueries, $delimiter);
                $result = $dumper->run();

                if ($result['finished']) {
                    $_SESSION['success'] = 'Import finished successfully!';
                    header('Location: .');
                    exit;
                } else {
                    // Redirect to continue
                    $query_params = http_build_query([
                        'action' => 'import',
                        'file' => $filename,
                        'start_line' => $result['linenumber'],
                        'foffset' => $result['foffset'],
                        'totalqueries' => $result['totalqueries'],
                        'delimiter' => $result['delimiter'],
                    ]);
                    // To prevent browser caching the redirect
                    header("Location: ?{$query_params}", true, 302);
                    exit;
                }
            }
            break;

        case 'start':
        default:
            $files = $fileHandler->getAvailableDumps();
            $db_connection_charset = '';
            try {
                if (!empty($config->db_name)) {
                    $db->connect();
                    $db_connection_charset = $db->getVariable('character_set_connection');
                }
            } catch (\Exception $e) {
                // Ignore db connection errors on start page
            }

            $error = $_SESSION['error'] ?? null;
            $success = $_SESSION['success'] ?? null;
            unset($_SESSION['error'], $_SESSION['success']);

            $content = renderTemplate('start.php', [
                'files' => $files,
                'db_connection_charset' => $db_connection_charset,
                'error' => $error,
                'success' => $success,
            ]);
            echo renderTemplate('layout.php', ['content' => $content]);
            break;
    }
} catch (\Exception $e) {
    $_SESSION['error'] = 'An error occurred: ' . $e->getMessage();
    //header('Location: .');
    //exit;
    echo "An error occurred: " . $e->getMessage();
}


function renderTemplate(string $templateName, array $data = []): string
{
    $templatePath = __DIR__ . '/../templates/' . $templateName;
    ob_start();
    extract($data);
    require $templatePath;
    return ob_get_clean();
}