<?php
/**
 * Copyright 2018 Kacper Donat
 *
 * @author Kacper "Kadet" Donat <kacper@kadet.net>
 *
 * Full license available in separate LICENSE file
 */

use \Kadet\Functional as f;

class FunctionPipelineTest extends \PHPUnit\Framework\TestCase
{
    /** @var \PHPUnit\Framework\MockObject\MockObject */
    private $mock;

    protected function setUp(): void
    {
        $this->mock = $this->createMock(PipelineSteps::class);
    }

    public function testPipelineCalling()
    {
        $pipeline = f\pipe(
            [$this->mock, 'a'],
            [$this->mock, 'b']
        );

        $this->mock->method('a')->willReturn('b');
        $this->mock->method('b')->willReturn('c');

        $this->mock->expects($this->once())->method('a')->with('a');
        $this->mock->expects($this->once())->method('b')->with('b');

        $this->assertSame('c', $pipeline('a'));
    }

    public function testPipelineForward()
    {
        $pipeline = f\pipe(
            [$this->mock, 'a']
        );

        $this->mock->method('a')->willReturn('b');

        $this->mock->expects($this->once())->method('a')->with('a');

        $this->assertSame('b', $pipeline('a'));
    }

    public function testPipelineAppend()
    {
        $pipeline = f\pipe(
            [$this->mock, 'a'],
            [$this->mock, 'b']
        );

        $second = $pipeline->append([$this->mock, 'c']);

        $this->mock->method('a')->willReturn('b');
        $this->mock->method('b')->willReturn('c');
        $this->mock->method('c')->willReturn('d');

        $this->mock->expects($this->exactly(2))->method('a')->with('a');
        $this->mock->expects($this->exactly(2))->method('b')->with('b');
        $this->mock->expects($this->once())->method('c')->with('c');

        $this->assertSame('c', $pipeline('a'));
        $this->assertSame('d', $second('a'));
    }

    public function testPipelinePrepend()
    {
        $pipeline = f\pipe(
            [$this->mock, 'b'],
            [$this->mock, 'c']
        );

        $second = $pipeline->prepend([$this->mock, 'a']);

        $this->mock->method('a')->willReturn('b');
        $this->mock->method('b')->willReturn('c');
        $this->mock->method('c')->willReturn('d');

        $this->mock->expects($this->exactly(1))->method('a')->with('a');
        $this->mock->expects($this->exactly(2))->method('b')->with('b');
        $this->mock->expects($this->exactly(2))->method('c')->with('c');

        $this->assertSame('d', $pipeline('b'));
        $this->assertSame('d', $second('a'));
    }
}

class PipelineSteps
{
    public function a() {}
    public function b() {}
    public function c() {}
}