<?php
/**
 * Template Builder AJAX Handler
 * Handles all AJAX requests for the template builder
 */

// Include core configuration
require_once dirname(__FILE__) . '/../../f_core/config.core.php';

// Check if user is logged in
if (!isset($_SESSION['USER_ID']) || $_SESSION['USER_ID'] <= 0) {
    http_response_code(401);
    echo json_encode(['success' => false, 'error' => 'Unauthorized']);
    exit;
}

// Initialize template builder class
require_once $cfg['classes_dir'] . '/class.templatebuilder.php';
$templateBuilder = new VTemplateBuilder();

// Get request data
$action = isset($_GET['action']) ? $_GET['action'] : (isset($_POST['action']) ? $_POST['action'] : '');

// Handle different actions
switch ($action) {
    case 'get_components':
        handleGetComponents($templateBuilder);
        break;

    case 'create_template':
        handleCreateTemplate($templateBuilder);
        break;

    case 'update_template':
        handleUpdateTemplate($templateBuilder);
        break;

    case 'delete_template':
        handleDeleteTemplate($templateBuilder);
        break;

    case 'get_template':
        handleGetTemplate($templateBuilder);
        break;

    case 'get_templates':
        handleGetTemplates($templateBuilder);
        break;

    case 'publish_template':
        handlePublishTemplate($templateBuilder);
        break;

    case 'duplicate_template':
        handleDuplicateTemplate($templateBuilder);
        break;

    case 'preview':
        handlePreview($templateBuilder);
        break;

    case 'render':
        handleRender($templateBuilder);
        break;

    default:
        http_response_code(400);
        echo json_encode(['success' => false, 'error' => 'Invalid action']);
        break;
}

/**
 * Get all available components
 */
function handleGetComponents($templateBuilder)
{
    $category = isset($_GET['category']) ? $_GET['category'] : null;
    $components = $templateBuilder->getComponents($category);

    echo json_encode([
        'success' => true,
        'components' => $components
    ]);
}

/**
 * Create new template
 */
function handleCreateTemplate($templateBuilder)
{
    $data = getJsonInput();

    if (!$data) {
        echo json_encode(['success' => false, 'error' => 'Invalid request data']);
        return;
    }

    $result = $templateBuilder->createTemplate($data);
    echo json_encode($result);
}

/**
 * Update existing template
 */
function handleUpdateTemplate($templateBuilder)
{
    $data = getJsonInput();

    if (!$data || !isset($data['template_id'])) {
        echo json_encode(['success' => false, 'error' => 'Invalid request data']);
        return;
    }

    $templateId = (int)$data['template_id'];
    $changeNote = isset($data['change_note']) ? $data['change_note'] : null;

    $result = $templateBuilder->updateTemplate($templateId, $data, $changeNote);
    echo json_encode($result);
}

/**
 * Delete template
 */
function handleDeleteTemplate($templateBuilder)
{
    $data = getJsonInput();

    if (!$data || !isset($data['template_id'])) {
        echo json_encode(['success' => false, 'error' => 'Invalid request data']);
        return;
    }

    $templateId = (int)$data['template_id'];
    $result = $templateBuilder->deleteTemplate($templateId);
    echo json_encode($result);
}

/**
 * Get template by ID
 */
function handleGetTemplate($templateBuilder)
{
    $templateId = isset($_GET['template_id']) ? (int)$_GET['template_id'] : 0;

    if ($templateId <= 0) {
        echo json_encode(['success' => false, 'error' => 'Invalid template ID']);
        return;
    }

    $template = $templateBuilder->getTemplate($templateId);

    if ($template) {
        echo json_encode(['success' => true, 'template' => $template]);
    } else {
        echo json_encode(['success' => false, 'error' => 'Template not found']);
    }
}

/**
 * Get all templates for current user
 */
function handleGetTemplates($templateBuilder)
{
    $filters = [];

    if (isset($_GET['template_type'])) {
        $filters['template_type'] = $_GET['template_type'];
    }

    if (isset($_GET['is_active'])) {
        $filters['is_active'] = (int)$_GET['is_active'];
    }

    if (isset($_GET['limit'])) {
        $filters['limit'] = (int)$_GET['limit'];
    }

    $templates = $templateBuilder->getUserTemplates($filters);

    echo json_encode([
        'success' => true,
        'templates' => $templates,
        'count' => count($templates)
    ]);
}

/**
 * Publish template (make active)
 */
function handlePublishTemplate($templateBuilder)
{
    $data = getJsonInput();

    if (!$data || !isset($data['template_id'])) {
        echo json_encode(['success' => false, 'error' => 'Invalid request data']);
        return;
    }

    $templateId = (int)$data['template_id'];

    $result = $templateBuilder->updateTemplate($templateId, [
        'is_active' => 1
    ], 'Published template');

    echo json_encode($result);
}

/**
 * Duplicate template
 */
function handleDuplicateTemplate($templateBuilder)
{
    $data = getJsonInput();

    if (!$data || !isset($data['template_id'])) {
        echo json_encode(['success' => false, 'error' => 'Invalid request data']);
        return;
    }

    $templateId = (int)$data['template_id'];
    $newName = isset($data['new_name']) ? $data['new_name'] : null;

    $result = $templateBuilder->duplicateTemplate($templateId, $newName);
    echo json_encode($result);
}

/**
 * Preview template
 */
function handlePreview($templateBuilder)
{
    $templateId = isset($_GET['template_id']) ? (int)$_GET['template_id'] : 0;

    if ($templateId <= 0) {
        echo 'Invalid template ID';
        return;
    }

    $template = $templateBuilder->getTemplate($templateId, false);

    if (!$template) {
        echo 'Template not found';
        return;
    }

    // Render template
    $html = $templateBuilder->renderTemplate($templateId);

    // Output as HTML page
    ?>
    <!DOCTYPE html>
    <html>
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>Preview: <?php echo htmlspecialchars($template['template_name']); ?></title>
        <link rel="stylesheet" href="<?php echo $cfg['styles_url']; ?>/init0.min.css">
        <link rel="stylesheet" href="<?php echo $cfg['styles_url']; ?>/theme/theme.min.css">
        <style>
            body {
                margin: 0;
                padding: 20px;
                background: #f5f5f5;
            }
            .preview-container {
                max-width: <?php echo $template['template_structure']['max_width'] ?? 1200; ?>px;
                margin: 0 auto;
                background: white;
                padding: 20px;
                box-shadow: 0 2px 4px rgba(0,0,0,0.1);
            }
        </style>
    </head>
    <body>
        <div class="preview-container">
            <?php echo $html; ?>
        </div>
    </body>
    </html>
    <?php
}

/**
 * Render template (for frontend display)
 */
function handleRender($templateBuilder)
{
    $templateId = isset($_GET['template_id']) ? (int)$_GET['template_id'] : 0;
    $slug = isset($_GET['slug']) ? $_GET['slug'] : '';

    if ($templateId > 0) {
        $html = $templateBuilder->renderTemplate($templateId);
    } elseif ($slug) {
        $html = $templateBuilder->renderTemplate($slug);
    } else {
        echo json_encode(['success' => false, 'error' => 'Template ID or slug required']);
        return;
    }

    echo json_encode([
        'success' => true,
        'html' => $html
    ]);
}

/**
 * Get JSON input from request body
 */
function getJsonInput()
{
    $input = file_get_contents('php://input');

    if (empty($input)) {
        return $_POST;
    }

    $data = json_decode($input, true);

    if (json_last_error() !== JSON_ERROR_NONE) {
        VLogger::log('ERROR', 'JSON decode error in template builder AJAX', [
            'error' => json_last_error_msg(),
            'input' => substr($input, 0, 1000)
        ]);
        return null;
    }

    return $data;
}