<?php
require_once '../include/init.php';
require_once '../include/auth.php'; // ensures user is logged in

header('Content-Type: application/json');

$method = $_SERVER['REQUEST_METHOD'];
$response = [];

try {
    switch ($method) {
        case 'GET':
            // Get all tabs
            $stmt = $pdo->query("SELECT * FROM tabs ORDER BY id");
            $response = $stmt->fetchAll();
            break;

        case 'POST':
            // Create a new tab
            $data = json_decode(file_get_contents('php://input'), true);
            if (isset($data['name'])) {
                $stmt = $pdo->prepare("INSERT INTO tabs (name, user_id) VALUES (?, ?)");
                $stmt->execute([$data['name'], $data['user_id'] ?? null]);
                $response = ['id' => $pdo->lastInsertId(), 'name' => $data['name']];
            } else {
                http_response_code(400); // Bad Request
                $response = ['error' => 'Name is required'];
            }
            break;

        case 'PUT':
            // Update a tab
            $data = json_decode(file_get_contents('php://input'), true);
            if (isset($data['id']) && isset($data['name'])) {
                // Prepare fields to update
                $fields = [
                    'name' => $data['name'],
                    'user_id' => $data['user_id'] ?? null,
                    'background_image_url' => $data['background_image_url'] ?? null,
                    'background_brightness' => $data['background_brightness'] ?? 100,
                    'background_saturation' => $data['background_saturation'] ?? 100,
                    'theme' => $data['theme'] ?? null,
                    'theme_transparency' => $data['theme_transparency'] ?? null,
                    'column_count' => $data['column_count'] ?? 5,
                ];

                // Handle empty strings to set them to NULL for proper fallback
                if ($fields['background_image_url'] === '') {
                    $fields['background_image_url'] = null;
                }
                if ($fields['theme'] === '') {
                    $fields['theme'] = null;
                }
                if ($fields['theme_transparency'] === '' || !is_numeric($fields['theme_transparency'])) {
                    $fields['theme_transparency'] = null;
                }
                
                $stmt = $pdo->prepare("
                    UPDATE tabs 
                    SET 
                        name = :name, 
                        user_id = :user_id,
                        background_image_url = :background_image_url,
                        background_brightness = :background_brightness,
                        background_saturation = :background_saturation,
                        theme = :theme,
                        theme_transparency = :theme_transparency,
                        column_count = :column_count
                    WHERE id = :id
                ");
                
                $fields['id'] = $data['id'];
                $stmt->execute($fields);

                $response = ['success' => true];
            } else {
                http_response_code(400); // Bad Request
                $response = ['error' => 'ID and name are required'];
            }
            break;

        case 'DELETE':
            // Delete a tab
            $data = json_decode(file_get_contents('php://input'), true);
            if (isset($data['id'])) {
                $stmt = $pdo->prepare("DELETE FROM tabs WHERE id = ?");
                $stmt->execute([$data['id']]);
                $response = ['success' => true];
            } else {
                http_response_code(400); // Bad Request
                $response = ['error' => 'ID is required'];
            }
            break;
        
        default:
            http_response_code(405); // Method Not Allowed
            $response = ['error' => 'Method not allowed'];
            break;
    }
} catch (PDOException $e) {
    http_response_code(500); // Internal Server Error
    $response = ['error' => 'Database error: ' . $e->getMessage()];
}

echo json_encode($response);