<?php

declare(strict_types=1);

namespace LIT\MCP\Tests\Unit\Integrations\WordPress\Schema;

use Brain\Monkey\Functions;
use LIT\MCP\Integrations\WordPress\Schema\FieldDefinition;
use LIT\MCP\Integrations\WordPress\Schema\RegisteredMetaSource;
use LIT\MCP\Tests\Unit\TestCase;
use RuntimeException;

final class RegisteredMetaSourceTest extends TestCase
{
    /** @return array<string, array<string, mixed>> */
    private function fieldsByKey(): array
    {
        Functions\when('get_registered_meta_keys')->alias(static function (string $type, string $sub = ''): array {
            if ($sub === '') {
                return ['footnotes' => ['type' => 'string', 'single' => true, 'show_in_rest' => true]];
            }

            return [
                '_internal' => ['type' => 'integer', 'single' => true, 'show_in_rest' => false],
                'tags_list' => ['type' => 'array', 'single' => false, 'description' => 'Liste'],
            ];
        });
        Functions\when('is_protected_meta')->alias(static fn (string $key): bool => str_starts_with($key, '_'));

        $fields = (new RegisteredMetaSource())->fieldsFor('event');

        return array_column(array_map(static fn (FieldDefinition $f): array => $f->toArray(), $fields), null, 'key');
    }

    public function testDescribesGlobalAndSubtypeMetaKeys(): void
    {
        $fields = $this->fieldsByKey();

        self::assertSame(['footnotes', '_internal', 'tags_list'], array_keys($fields));
        self::assertSame('string', $fields['footnotes']['type']);
        self::assertSame(FieldDefinition::WRITABLE, $fields['footnotes']['status']);
        self::assertSame('meta', $fields['footnotes']['source']);
        self::assertFalse($fields['footnotes']['multiple']);
    }

    public function testProtectedMetaHiddenFromRestIsReadonly(): void
    {
        $fields = $this->fieldsByKey();

        self::assertSame(FieldDefinition::READONLY, $fields['_internal']['status']);
        self::assertSame('integer', $fields['_internal']['type']);
    }

    public function testNonSingleMetaIsMultiple(): void
    {
        $fields = $this->fieldsByKey();

        self::assertTrue($fields['tags_list']['multiple']);
        self::assertSame('Liste', $fields['tags_list']['description']);
    }

    public function testReadUsesSingleOrMultipleMeta(): void
    {
        Functions\expect('get_post_meta')->once()->with(5, 'footnotes', true)->andReturn('x');
        Functions\expect('get_post_meta')->once()->with(5, 'tags_list', false)->andReturn(['a', 'b']);
        $source = new RegisteredMetaSource();

        self::assertSame('x', $source->read(5, new FieldDefinition('footnotes', 'footnotes', 'string', 'meta', 'writable')));
        self::assertSame(
            ['a', 'b'],
            $source->read(5, new FieldDefinition('tags_list', 'tags_list', 'array', 'meta', 'writable', false, true))
        );
    }

    public function testWriteUpdatesReplacesListsAndDeletesNull(): void
    {
        $single = new FieldDefinition('footnotes', 'footnotes', 'string', 'meta', 'writable');
        $multi = new FieldDefinition('tags_list', 'tags_list', 'array', 'meta', 'writable', false, true);
        $gone = new FieldDefinition('old', 'old', 'string', 'meta', 'writable');
        Functions\expect('update_post_meta')->once()->with(5, 'footnotes', 'neu');
        Functions\expect('delete_post_meta')->once()->with(5, 'tags_list');
        Functions\expect('add_post_meta')->once()->with(5, 'tags_list', 'a');
        Functions\expect('add_post_meta')->once()->with(5, 'tags_list', 'b');
        Functions\expect('delete_post_meta')->once()->with(5, 'old');

        (new RegisteredMetaSource())->write(
            5,
            'event',
            ['footnotes' => 'neu', 'tags_list' => ['a', 'b'], 'old' => null],
            ['footnotes' => $single, 'tags_list' => $multi, 'old' => $gone]
        );
    }

    public function testUnchangedValueIsNotAFailure(): void
    {
        $field = new FieldDefinition('count', 'count', 'integer', 'meta', 'writable');
        Functions\expect('update_post_meta')->once()->with(5, 'count', 3)->andReturn(false);
        Functions\expect('get_post_meta')->once()->with(5, 'count', false)->andReturn(['3']);

        (new RegisteredMetaSource())->write(5, 'event', ['count' => 3], ['count' => $field]);
        self::addToAssertionCount(1);
    }

    public function testFailedUpdateThrows(): void
    {
        $field = new FieldDefinition('count', 'count', 'integer', 'meta', 'writable');
        Functions\when('update_post_meta')->justReturn(false);
        Functions\when('get_post_meta')->justReturn(['2']);

        $this->expectException(RuntimeException::class);
        (new RegisteredMetaSource())->write(5, 'event', ['count' => 3], ['count' => $field]);
    }

    public function testFailedDeleteOfAnExistingKeyThrows(): void
    {
        $field = new FieldDefinition('old', 'old', 'string', 'meta', 'writable');
        Functions\when('delete_post_meta')->justReturn(false);
        Functions\expect('metadata_exists')->once()->with('post', 5, 'old')->andReturn(true);

        $this->expectException(RuntimeException::class);
        (new RegisteredMetaSource())->write(5, 'event', ['old' => null], ['old' => $field]);
    }

    public function testDeletingAMissingKeyIsNotAFailure(): void
    {
        $field = new FieldDefinition('old', 'old', 'string', 'meta', 'writable');
        Functions\when('delete_post_meta')->justReturn(false);
        Functions\expect('metadata_exists')->once()->with('post', 5, 'old')->andReturn(false);

        (new RegisteredMetaSource())->write(5, 'event', ['old' => null], ['old' => $field]);
        self::addToAssertionCount(1);
    }

    public function testFailedAddOfAListItemThrows(): void
    {
        $multi = new FieldDefinition('tags_list', 'tags_list', 'array', 'meta', 'writable', false, true);
        Functions\when('delete_post_meta')->justReturn(true);
        Functions\when('add_post_meta')->justReturn(false);

        $this->expectException(RuntimeException::class);
        (new RegisteredMetaSource())->write(5, 'event', ['tags_list' => ['a']], ['tags_list' => $multi]);
    }
}