api.php

<?php
declare(strict_types=1);

ini_set('html_errors', 'false');
error_reporting(E_ALL | E_STRICT);
set_exception_handler('error');

define('DB_HOST', '127.0.0.1');
define('DB_USER', 'root');
define('DB_PASS', null);
define('DB_NAME', 'untitled');

/**
 * Response handler.
 *
 * @param int $status
 * @param mixed $data
 */
function respond(int $status, $data = null): void
{
    http_response_code($status);
    header('Content-Type: application/json');
    if ($data !== null) {
        echo json_encode($data, JSON_PRETTY_PRINT);
    }
    die;
}

/**
 * Catch-all error handler.
 *
 * @param Throwable $throwable
 */
function error(Throwable $throwable): void
{
    respond(500, $throwable->getMessage());
}

$pdo = new PDO(
    sprintf('mysql:host=%s;dbname=%s', DB_HOST, DB_NAME),
    DB_USER,
    DB_PASS,
    [
        PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
    ]
);

/**
 * Fetch company entity with embedded company_addresses.
 *
 * @param PDO $pdo
 * @param int $id
 * @return array
 */
function fetch_company(PDO $pdo, int $id = null): array
{
    $sql = 'SELECT * FROM company';
    if ($id !== null) {
        $sql = 'SELECT * FROM company WHERE company.id = :id';
    }
    $statement = $pdo->prepare($sql);
    $statement->bindParam(':id', $id, PDO::PARAM_INT);
    $statement->execute();
    $result = [];
    while ($row = $statement->fetch()) {
        $sql = 'SELECT * FROM company_address WHERE company_address.company_id = :id';
        $statement2 = $pdo->prepare($sql);
        $statement2->bindParam(':id', $row['id'], PDO::PARAM_INT);
        $statement2->execute();
        $row['addresses'] = $statement2->fetchAll();
        $result[] = $row;
    }

    return $result;
}

// Parse request body.
$data = json_decode(file_get_contents('php://input'), true);

// Controllers.
$routes = [
    '/^\/$/' => [
        'GET' => function () use ($pdo) {
            respond(200, fetch_company($pdo));
        },

        'POST' => function () use ($pdo, $data) {
            $sql = 'INSERT INTO company (name, description) VALUES (:name, :description)';
            $statement = $pdo->prepare($sql);
            $statement->bindParam(':name', $data['name']);
            $statement->bindParam(':description', $data['description']);
            $statement->execute();
            $id = (int)$pdo->lastInsertId();
            $sql = 'INSERT INTO company_address (company_id, address, address_2, city, state, zip) VALUES (:company_id, :address, :address_2, :city, :state, :zip)';
            $statement = $pdo->prepare($sql);
            $statement->bindParam(':company_id', $id, PDO::PARAM_INT);
            $statement->bindParam(':address', $data['address']);
            $statement->bindParam(':address_2', $data['address_2']);
            $statement->bindParam(':city', $data['city']);
            $statement->bindParam(':state', $data['state']);
            $statement->bindParam(':zip', $data['zip']);
            $statement->execute();
            $pdo->commit();
            respond(201, fetch_company($pdo, $id));
        },
    ],

    '/^\/[0-9]+$/' => [
        'GET' => function (int $id) use ($pdo) {
            respond(200, fetch_company($pdo, $id));
        },

        'DELETE' => function (int $id) use ($pdo) {
            $statement = $pdo->prepare('DELETE FROM company WHERE id = :id');
            $statement->bindParam(':id', $id, PDO::PARAM_INT);
            $statement->execute();
            $pdo->commit();
            respond(200, 'Deleted.');
        },

        'PUT' => function (int $id) use ($pdo, $data) {
            $table_fields = [
                'company'         => ['name', 'description'],
                'company_address' => ['address', 'address_2', 'city', 'state', 'zip'],
            ];
            $params = [];
            /** @var string[] $fields */
            foreach ($table_fields as $table => $fields) {
                foreach ($fields as $field) {
                    if (array_key_exists($field, $data)) {
                        $params[$field] = sprintf('%1$s.%2$s = :%2$s', $table, $field);
                    }
                }
            }
            $sql = sprintf('UPDATE company LEFT JOIN company_address ON (company.id = company_address.company_id) SET %s WHERE (company.id = :id)', implode(', ', $params));
            $statement = $pdo->prepare($sql);
            foreach ($params as $field => $param) {
                $statement->bindParam(':'.$field, $data[$field]);
            }
            $statement->bindParam(':id', $id, PDO::PARAM_INT);
            $statement->execute();
            $pdo->commit();
            respond(200, fetch_company($pdo, $id));
        },
    ],
];

// Router.
//['REQUEST_URI' => $uri, 'REQUEST_METHOD' => $method] = $_SERVER
/** @var callable[] $route */
foreach ($routes as $uri => $route) {
    if (preg_match($uri, $_SERVER['REQUEST_URI'], $matches)) {
        foreach ($route as $method => $controller) {
            if ($method === $_SERVER['REQUEST_METHOD']) {
                $id = null;
                if (count($matches) > 1) {
                    $id = (int)ltrim(array_shift($matches), '/');
                }
                if ($id) {
                    $sql = 'SELECT id FROM company WHERE id = :id';
                    $statement = $pdo->prepare($sql);
                    $statement->bindParam(':id', $id);
                    $statement->execute();
                    if ($statement->fetch() === false) {
                        respond(404);
                    }
                }
                try {
                    $pdo->beginTransaction();
                    $controller($id);
                } catch (PDOException $exception) {
                    $pdo->rollBack();
                    if ($exception->getCode() === '23000') {
                        respond(422, $exception->getMessage());
                    }
                    throw $exception;
                }
            }
        }
        respond(405);
    }
}
respond(404);