<?php
/**
 * Copyright 2026 Kacper Donat
 *
 * @author Kacper "Kadet" Donat <kacper@kadet.net>
 *
 * Full license available in separate LICENSE file
 */

use Kadet\Functional as f;
use function Kadet\Functional\Collections\Internal\callback;
use const Kadet\Functional\_;

class CallbackTest extends \PHPUnit\Framework\TestCase
{
    public function testInternalFunctionGetsValueOnly()
    {
        $this->assertSame('a', callback(trim(...))(' a ', 'xyz'));
    }

    public function testInternalStringCallableGetsValueOnly()
    {
        $this->assertSame('A', callback('strtoupper')('a', 'key'));
    }

    public function testSingleParamClosureGetsValueOnly()
    {
        $this->assertSame([1], callback(function ($v) { return func_get_args(); })(1, 'k'));
    }

    public function testTwoParamClosureGetsKey()
    {
        $this->assertSame('k=v', callback(fn ($v, $k) => "$k=$v")('v', 'k'));
    }

    public function testVariadicClosureGetsKey()
    {
        $this->assertSame(['v', 'k'], callback(fn (...$args) => $args)('v', 'k'));
    }

    public function testPartialOfInternalFunctionDoesNotGetKey()
    {
        $this->assertSame('a', callback(f\partial(trim(...), _, 'x'))('xax', 'key'));
    }

    public function testDecoratorIsCompiled()
    {
        $callback = callback(f\partial(fn ($prefix, $v, $k) => "$prefix$k=$v", '>'));

        $this->assertSame('>k=v', $callback('v', 'k'));
    }
}