api.php

<?php
// api.php - Main API File for TaskFlow
// Save this as: api.php

header("Access-Control-Allow-Origin: *");
header("Content-Type: application/json; charset=UTF-8");
header("Access-Control-Allow-Methods: GET, POST, PUT, DELETE");
header("Access-Control-Allow-Headers: Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With");

require_once 'config.php';

// Get request method
$method = $_SERVER['REQUEST_METHOD'];

// Get the endpoint
$request = isset($_GET['request']) ? $_GET['request'] : '';

// Database connection
$database = new Database();
$db = $database->getConnection();

// Response array
$response = array();

// ============ HANDLE API REQUESTS ============

switch($method) {
    case 'GET':
        if ($request === 'tasks') {
            // Get all tasks
            $query = "SELECT * FROM tasks ORDER BY created_at DESC";
            $stmt = $db->prepare($query);
            $stmt->execute();
            
            $tasks = $stmt->fetchAll(PDO::FETCH_ASSOC);
            
            $response = array(
                "success" => true,
                "tasks" => $tasks
            );
        } 
        elseif (preg_match('/^tasks\/(\d+)$/', $request, $matches)) {
            // Get single task by ID
            $id = $matches[1];
            
            $query = "SELECT * FROM tasks WHERE id = :id";
            $stmt = $db->prepare($query);
            $stmt->bindParam(":id", $id);
            $stmt->execute();
            
            $task = $stmt->fetch(PDO::FETCH_ASSOC);
            
            if ($task) {
                $response = array(
                    "success" => true,
                    "task" => $task
                );
            } else {
                http_response_code(404);
                $response = array(
                    "success" => false,
                    "message" => "Task not found"
                );
            }
        }
        break;
        
    case 'POST':
        if ($request === 'tasks') {
            // Create new task
            $data = json_decode(file_get_contents("php://input"));
            
            if (!empty($data->title)) {
                $query = "INSERT INTO tasks (title, priority, due_date, completed) 
                          VALUES (:title, :priority, :due_date, :completed)";
                
                $stmt = $db->prepare($query);
                
                $title = htmlspecialchars(strip_tags($data->title));
                $priority = isset($data->priority) ? $data->priority : 'medium';
                $due_date = isset($data->due_date) ? $data->due_date : null;
                $completed = isset($data->completed) ? $data->completed : 0;
                
                $stmt->bindParam(":title", $title);
                $stmt->bindParam(":priority", $priority);
                $stmt->bindParam(":due_date", $due_date);
                $stmt->bindParam(":completed", $completed);
                
                if ($stmt->execute()) {
                    http_response_code(201);
                    $response = array(
                        "success" => true,
                        "message" => "Task created successfully",
                        "taskId" => $db->lastInsertId()
                    );
                } else {
                    http_response_code(500);
                    $response = array(
                        "success" => false,
                        "message" => "Unable to create task"
                    );
                }
            } else {
                http_response_code(400);
                $response = array(
                    "success" => false,
                    "message" => "Title is required"
                );
            }
        }
        break;
        
    case 'PUT':
        if (preg_match('/^tasks\/(\d+)$/', $request, $matches)) {
            // Update task
            $id = $matches[1];
            $data = json_decode(file_get_contents("php://input"));
            
            $updates = array();
            $params = array();
            
            if (isset($data->title)) {
                $updates[] = "title = :title";
                $params[':title'] = htmlspecialchars(strip_tags($data->title));
            }
            if (isset($data->priority)) {
                $updates[] = "priority = :priority";
                $params[':priority'] = $data->priority;
            }
            if (isset($data->due_date)) {
                $updates[] = "due_date = :due_date";
                $params[':due_date'] = $data->due_date;
            }
            if (isset($data->completed)) {
                $updates[] = "completed = :completed";
                $params[':completed'] = $data->completed;
            }
            
            if (count($updates) > 0) {
                $query = "UPDATE tasks SET " . implode(", ", $updates) . " WHERE id = :id";
                $stmt = $db->prepare($query);
                
                $params[':id'] = $id;
                
                if ($stmt->execute($params)) {
                    $response = array(
                        "success" => true,
                        "message" => "Task updated successfully"
                    );
                } else {
                    http_response_code(500);
                    $response = array(
                        "success" => false,
                        "message" => "Unable to update task"
                    );
                }
            } else {
                http_response_code(400);
                $response = array(
                    "success" => false,
                    "message" => "No fields to update"
                );
            }
        }
        break;
        
    case 'DELETE':
        if (preg_match('/^tasks\/(\d+)$/', $request, $matches)) {
            // Delete task
            $id = $matches[1];
            
            $query = "DELETE FROM tasks WHERE id = :id";
            $stmt = $db->prepare($query);
            $stmt->bindParam(":id", $id);
            
            if ($stmt->execute()) {
                $response = array(
                    "success" => true,
                    "message" => "Task deleted successfully"
                );
            } else {
                http_response_code(500);
                $response = array(
                    "success" => false,
                    "message" => "Unable to delete task"
                );
            }
        }
        break;
        
    default:
        http_response_code(405);
        $response = array(
            "success" => false,
            "message" => "Method not allowed"
        );
        break;
}

// Output response
echo json_encode($response);
?>