<?php

namespace Tests\Unit;

use App\Services\ThreeMfTransform;
use RuntimeException;
use Tests\TestCase;

class ThreeMfTransformTest extends TestCase
{
    public function test_identity_leaves_a_point_unchanged(): void
    {
        $this->assertSame([1.0, 2.0, 3.0], ThreeMfTransform::apply(ThreeMfTransform::identity(), [1.0, 2.0, 3.0]));
    }

    public function test_parses_twelve_space_separated_floats(): void
    {
        $matrix = ThreeMfTransform::parse('1 0 0 0 1 0 0 0 1 10 20 30');

        $this->assertSame([10.0, 20.0, 33.0], ThreeMfTransform::apply($matrix, [0.0, 0.0, 3.0]));
    }

    public function test_rejects_a_transform_without_exactly_twelve_values(): void
    {
        $this->expectException(RuntimeException::class);
        ThreeMfTransform::parse('1 0 0 0 1 0 0 0 1');
    }

    public function test_rejects_a_non_numeric_transform_value(): void
    {
        $this->expectException(RuntimeException::class);
        ThreeMfTransform::parse('1 0 0 0 1 0 0 0 1 x 0 0');
    }

    public function test_rejects_a_non_finite_transform_value(): void
    {
        $this->expectException(RuntimeException::class);
        ThreeMfTransform::parse('1 0 0 0 1 0 0 0 1 NAN 0 0');
    }

    public function test_translation_moves_a_point(): void
    {
        $translate = ThreeMfTransform::parse('1 0 0 0 1 0 0 0 1 5 6 7');

        $this->assertSame([6.0, 8.0, 10.0], ThreeMfTransform::apply($translate, [1.0, 2.0, 3.0]));
    }

    public function test_scale_multiplies_each_axis(): void
    {
        $scale = ThreeMfTransform::parse('2 0 0 0 3 0 0 0 4 0 0 0');

        $this->assertSame([2.0, 6.0, 12.0], ThreeMfTransform::apply($scale, [1.0, 2.0, 3.0]));
    }

    public function test_compose_applies_inner_transform_before_outer(): void
    {
        $translateThenScale = ThreeMfTransform::compose(
            outer: ThreeMfTransform::parse('2 0 0 0 2 0 0 0 2 0 0 0'),
            inner: ThreeMfTransform::parse('1 0 0 0 1 0 0 0 1 10 0 0'),
        );

        // Expected: apply(outer, apply(inner, p)) = apply(outer, [11,0,0]) = [22,0,0]
        $this->assertSame([22.0, 0.0, 0.0], ThreeMfTransform::apply($translateThenScale, [1.0, 0.0, 0.0]));
    }

    public function test_compose_matches_applying_each_transform_in_turn_for_an_arbitrary_rotation_like_matrix(): void
    {
        $outer = ThreeMfTransform::parse('0 1 0 -1 0 0 0 0 1 3 4 5');
        $inner = ThreeMfTransform::parse('1 0 0 0 1 0 0 0 1 1 2 3');
        $point = [7.0, -2.0, 0.5];

        $composed = ThreeMfTransform::compose($outer, $inner);

        $expected = ThreeMfTransform::apply($outer, ThreeMfTransform::apply($inner, $point));
        $this->assertSame($expected, ThreeMfTransform::apply($composed, $point));
    }
}