<?php

declare(strict_types=1);

namespace Tests\Unit;

use App\Services\SimulationTaxParameterResolver;
use InvalidArgumentException;
use PHPUnit\Framework\Attributes\Test;
use PHPUnit\Framework\TestCase;

final class SimulationTaxParameterResolverTest extends TestCase
{
    #[Test]
    public function it_selects_the_published_version_effective_on_the_requested_date_and_returns_its_source(): void
    {
        $old = $this->version('2025-01-01', '2025-12-31', '15', 1);
        $current = $this->version('2026-01-01', null, '16', 2);
        $resolver = new SimulationTaxParameterResolver;

        self::assertSame('15', $resolver->resolve([$old, $current], 'IVA', 'scope:test', '2025-12-31', 'VAT_RATE')['value']);
        $resolved = $resolver->resolve([$old, $current], 'IVA', 'scope:test', '2026-01-01', 'VAT_RATE');
        self::assertSame('resolved', $resolved['status']);
        self::assertSame('16', $resolved['value']);
        self::assertSame('LAW-2026', $resolved['source']['diploma']);
        self::assertSame(2, $resolved['rule_version']);
    }

    #[Test]
    public function it_returns_indeterminate_for_missing_or_overlapping_candidates(): void
    {
        $version = $this->version('2026-01-01', null, '16', 1);
        $resolver = new SimulationTaxParameterResolver;

        self::assertSame('indeterminate_missing', $resolver->resolve([], 'IVA', 'scope:test', '2026-07-01', 'VAT_RATE')['status']);
        self::assertSame('indeterminate_missing', $resolver->resolve([$version], 'IVA', 'different-scope', '2026-07-01', 'VAT_RATE')['status']);
        self::assertSame('indeterminate_missing', $resolver->resolve([$version], 'IVA', 'scope:test', '2025-12-31', 'VAT_RATE')['status']);
        self::assertSame('indeterminate_overlap', $resolver->resolve([$version, $version], 'IVA', 'scope:test', '2026-07-01', 'VAT_RATE')['status']);
    }

    #[Test]
    public function it_requires_exactly_matching_conditions_and_a_still_validated_source_version(): void
    {
        $version = $this->version('2026-01-01', null, '16', 1);
        $version['parameters']['VAT_RATE']['conditions'] = ['operation' => 'domestic'];
        $resolver = new SimulationTaxParameterResolver;

        self::assertSame('indeterminate_missing', $resolver->resolve([$version], 'IVA', 'scope:test', '2026-03-01', 'VAT_RATE', ['operation' => 'import'])['status']);
        $version['source_version_no'] = 2;
        self::assertSame('indeterminate_missing', $resolver->resolve([$version], 'IVA', 'scope:test', '2026-03-01', 'VAT_RATE', ['operation' => 'domestic'])['status']);
    }

    #[Test]
    public function it_rejects_negative_values_and_percentages_over_one_hundred(): void
    {
        $resolver = new SimulationTaxParameterResolver;
        foreach (['-0.01' => 'mzn', '100.0001' => 'percent'] as $value => $unit) {
            try {
                $resolver->validateParameters(['TEST_VALUE' => ['value' => $value, 'unit' => $unit, 'conditions' => []]]);
                self::fail('Invalid parameter value was accepted.');
            } catch (InvalidArgumentException) {
                self::assertTrue(true);
            }
        }
    }

    #[Test]
    public function it_does_not_select_a_parameter_when_its_validity_changes_inside_the_requested_period(): void
    {
        $before = $this->publicVersion('2026-01-01', '2026-06-30', '16', 1);
        $after = $this->publicVersion('2026-07-01', null, '17', 2);
        $resolver = new SimulationTaxParameterResolver;

        $result = $resolver->resolveAvailableParameters([$before, $after], 'IVA', '2026-01-01', '2026-12-31', ['operation' => 'domestic']);

        self::assertSame('indeterminate_period_change', $result[0]['status']);
        self::assertNull($result[0]['value']);
    }

    #[Test]
    public function it_resolves_a_single_parameter_only_for_an_exactly_matching_context(): void
    {
        $version = $this->publicVersion('2026-01-01', null, '16', 1);
        $resolver = new SimulationTaxParameterResolver;

        $result = $resolver->resolveAvailableParameters([$version], 'IVA', '2026-01-01', '2026-12-31', ['operation' => 'domestic']);

        self::assertSame('resolved', $result[0]['status']);
        self::assertSame('16', $result[0]['value']);
        self::assertSame('Synthetic source fixture', $result[0]['source']['title']);
    }

    /** @return array<string,mixed> */
    private function version(string $from, ?string $until, string $value, int $version): array
    {
        return [
            'id' => 'rule-'.$version,
            'rule_code' => 'IVA.VAT.RATE',
            'rule_version' => $version,
            'component' => 'IVA',
            'scope_key' => 'scope:test',
            'status' => 'published',
            'valid_from' => $from,
            'valid_until' => $until,
            'parameters' => ['VAT_RATE' => ['value' => $value, 'unit' => 'percent', 'conditions' => []]],
            'source_version_no' => 1,
            'source_sha256' => str_repeat('a', 64),
            'source' => [
                'validation_status' => 'validated',
                'version_no' => 1,
                'valid_from' => '2020-01-01',
                'valid_until' => null,
                'title' => 'Synthetic source fixture',
                'diploma' => 'LAW-2026',
                'article' => 'Article fixture',
                'url' => 'https://example.invalid/source',
            ],
        ];
    }

    /** @return array<string,mixed> */
    private function publicVersion(string $from, ?string $until, string $value, int $version): array
    {
        $record = $this->version($from, $until, $value, $version);
        $record['rule_definition'] = ['language' => 'investmoz.tax.v1'];
        $record['parameters']['VAT_RATE']['conditions'] = ['operation' => 'domestic'];

        return $record;
    }
}