<?php

class PHPUnit_ExceptionTrap
{
    /**
     * @var PHPUnit_Framework_TestCase
     */
    private $testCase;

    /**
     * @var Exception
     */
    private $trapped;

    /**
     * ExceptionTrap constructor.
     *
     * @param PHPUnit_Framework_TestCase $testCase
     */
    public function __construct(PHPUnit_Framework_TestCase $testCase)
    {
        $this->testCase = $testCase;
    }

    /**
     * @param callable $callable
     * @param string|object $expected [optional]
     * @return $this
     */
    public function trap(callable $callable, $expected = null)
    {
        $this->trapped = null;

        try {
            call_user_func($callable);
        } catch (Exception $e) {
            $this->trapped = $e;

            if ($expected !== null) {
                $className = is_string($expected) ? $expected : get_class($expected);
                $this->testCase->assertInstanceOf($className, $e);
            }
        }

        return $this;
    }

    /**
     * @param $expectedException
     * @return $this
     */
    public function exception($expectedException)
    {
        $this->testCase->assertInstanceOf(Exception::class, $this->trapped);

        /* @see PHPUnit_Framework_TestCase::runTest */
        $this->testCase->assertThat(
            $this->trapped,
            new PHPUnit_Framework_Constraint_Exception(
                $expectedException
            )
        );

        return $this;
    }

    /**
     * @param $expectedExceptionMessage
     * @return $this
     */
    public function message($expectedExceptionMessage)
    {
        $this->testCase->assertInstanceOf(Exception::class, $this->trapped);

        /* @see PHPUnit_Framework_TestCase::runTest */
        $this->testCase->assertThat(
            $this->trapped,
            new PHPUnit_Framework_Constraint_ExceptionMessage(
                $expectedExceptionMessage
            )
        );

        return $this;
    }
}