<?php

interface ApiOutputStrategy
{
    public function handle(): string;
}

class JsonOutput implements ApiOutputStrategy
{
    public function __construct($data)
    {
        $this->data = $data;
    }

    public function handle(): string
    {
        return json_encode($this->data);
    }
}

class XmlOutput implements ApiOutputStrategy
{
    public function __construct($data)
    {
        $this->data = $data;
    }

    public function handle(): string
    {
        $xml = '<root>';
        foreach($this->data as $key => $value)
        {
            $xml .= "<$key>$value</$key>";
        }
        $xml .= '</root>';

        return $xml;
    }
}

class SerializedArrayOutput implements ApiOutputStrategy
{
    public function __construct($data)
    {
        $this->data = $data;
    }

    public function handle(): string
    {
        return serialize($this->data);

    }
}

class ApiOutput
{
    /**
     * @param ApiOutputStrategy $strategy
     */
    public function __construct(ApiOutputStrategy $strategy)
    {
        $this->strategy = $strategy;
    }

    /**
     * @return void
     */
    public function output()
    {
        echo $this->strategy->handle();
    }
}


$data = [
    'name' => 'test',
    'secondName' => 'test2',
    'age' => 25
];


$strategy = new JsonOutput($data);
$api = new ApiOutput($strategy);
$api->output();

echo "\n\n";

$strategy = new XmlOutput($data);
$api = new ApiOutput($strategy);
$api->output();

echo "\n\n";

$strategy = new SerializedArrayOutput($data);
$api = new ApiOutput($strategy);
$api->output();

/*
result:
{"name":"test","secondName":"test2","age":25}

<root><name>test</name><secondName>test2</secondName><age>25</age></root>

a:3:{s:4:"name";s:4:"test";s:10:"secondName";s:5:"test2";s:3:"age";i:25;}
*/