<?php

declare(strict_types=1);

namespace LIT\MCP\Tests\Unit\Integrations\Divi\Design;

use Brain\Monkey\Functions;
use Closure;
use LIT\MCP\Abilities\WriteFailed;
use LIT\MCP\Integrations\Divi\BlockTree\Block;
use LIT\MCP\Integrations\Divi\BlockTree\GlobalInstance;
use LIT\MCP\Integrations\Divi\Design\NodeRewrite;
use LIT\MCP\Integrations\Divi\Design\PageRewriter;
use LIT\MCP\Integrations\Divi\Library\GlobalUsages;
use LIT\MCP\Integrations\Divi\Library\UsageQuery;
use LIT\MCP\Integrations\Divi\Library\UsageReport;
use LIT\MCP\Integrations\Divi\Pages\DiviPageLoader;
use LIT\MCP\Integrations\Divi\Pages\DiviSaver;
use LIT\MCP\Integrations\Divi\Pages\SaveScope;
use LIT\MCP\Integrations\Divi\Release\DiviFeature;
use LIT\MCP\Integrations\Divi\Release\DiviLocked;
use LIT\MCP\Integrations\Divi\Release\ReleaseState;
use LIT\MCP\Tests\Support\FakeChangeLog;
use LIT\MCP\Tests\Support\LibraryFixtures;
use LIT\MCP\Tests\Support\ReleaseMatrices;
use LIT\MCP\Tests\Unit\TestCase;
use Mockery;
use Throwable;
use WP_Post;

/** Spec §6.6, rulings R1, R8, R9: the page rewriter behind lit/divi-presets-assign and lit/divi-design-detach. */
final class PageRewriterTest extends TestCase
{
    /** The overlap note the test strategy adds to every block it changes. */
    public const NOTE = 'lokale Werte überdecken „CTA“';

    private const ABILITY = 'lit/divi-presets-assign';

    private const SUMMARY = 'Preset „CTA“ zugewiesen';

    private const BUTTON = '<!-- wp:divi/button {"builderVersion":"5.2.1"} /-->';

    private const TEXT = '<!-- wp:divi/text {"builderVersion":"5.2.1"} /-->';

    private const INSTANCE = '<!-- wp:divi/global-layout {"globalModule":"1059","blockName":"divi/button"} /-->';

    /** @var list<array{int, SaveScope}> Post ID and scope of every save. */
    private array $saved = [];

    /** @var list<Throwable|null> Thrown by the n-th save instead of saving (null = save). */
    private array $failures = [];

    private FakeChangeLog $log;

    protected function setUp(): void
    {
        parent::setUp();
        Functions\when('_get_non_cached_ids')->returnArg(1);
        Functions\when('_prime_post_caches')->justReturn(null);
        Functions\when('wp_cache_delete')->justReturn(true);
        Functions\when('wp_revisions_enabled')->justReturn(true);
        $this->log = new FakeChangeLog(1);
    }

    /** One section, row and column holding $modules (IDs s0.r0.c0.m0, …). */
    private static function layout(string ...$modules): string
    {
        return '<!-- wp:divi/placeholder --><!-- wp:divi/section {"builderVersion":"5.2.1"} -->'
            . '<!-- wp:divi/row {"builderVersion":"5.2.1"} --><!-- wp:divi/column {"builderVersion":"5.2.1"} -->'
            . implode('', $modules)
            . '<!-- /wp:divi/column --><!-- /wp:divi/row --><!-- /wp:divi/section --><!-- /wp:divi/placeholder -->';
    }

    /** @param array<string, mixed> $fields */
    private static function page(int $id, string $content, array $fields = []): WP_Post
    {
        return new WP_Post(array_merge([
            'ID' => $id,
            'post_type' => 'page',
            'post_status' => 'draft',
            'post_title' => 'Seite ' . $id,
            'post_content' => $content,
        ], $fields));
    }

    /** @param list<int> $blocked */
    private static function report(
        int $count,
        array $blocked = [],
        int $live = 0,
        bool $tooMany = false,
        int $hidden = 0
    ): UsageReport {
        return new UsageReport($count, [], $hidden, $live, $blocked, 0, $tooMany);
    }

    /**
     * The rewriter over $posts: they are the candidates (ID order) and what get_post() finds; the caller has every
     * capability. $report answers reportFor() (default: all posts, nothing blocked), $libraryReports report($id);
     * $loader defaults to one whose user may see library IDs.
     *
     * @param list<WP_Post>           $posts
     * @param array<int, UsageReport> $libraryReports
     */
    private function rewriter(
        array $posts,
        ?UsageReport $report = null,
        array $libraryReports = [],
        ?DiviPageLoader $loader = null
    ): PageRewriter {
        LibraryFixtures::given($posts);
        $rows = array_map(
            static fn (WP_Post $post): array => [
                'id' => (int) $post->ID,
                'status' => (string) $post->post_status,
                'type' => (string) $post->post_type,
            ],
            $posts
        );
        $usages = Mockery::mock(GlobalUsages::class);
        $usages->allows('rowsFor')->andReturn($rows);
        $usages->allows('reportFor')->andReturn($report ?? self::report(count($rows)));
        $usages->allows('report')->andReturnUsing(
            static fn (int $id): UsageReport => $libraryReports[$id] ?? self::report(0)
        );

        return new PageRewriter($usages, $loader ?? LibraryFixtures::loader(), $this->saver(), $this->log);
    }

    /** Records post ID and scope, puts the content on the post and reports revision 900 + n. */
    private function saver(): DiviSaver
    {
        $saver = Mockery::mock(DiviSaver::class);
        $saver->allows('save')->andReturnUsing(function (WP_Post $post, string $content, SaveScope $scope): array {
            $failure = array_shift($this->failures);
            if ($failure !== null) {
                throw $failure;
            }
            $this->saved[] = [(int) $post->ID, $scope];
            $post->post_content = $content;

            return ['revision_id' => 900 + count($this->saved), 'warnings' => []];
        });

        return $saver;
    }

    /**
     * A strategy like AssignRewrite: every block of $modules gets the preset stack ["p-cta"] (a block that has it
     * stays), each changed block an overlap note; global instances of these modules concern the change.
     *
     * @param list<string> $modules
     * @return Closure(): NodeRewrite
     */
    private static function assign(array $modules = ['divi/button']): Closure
    {
        return static fn (): NodeRewrite => new class ($modules) implements NodeRewrite {
            /** @param list<string> $modules */
            public function __construct(private array $modules)
            {
            }

            public function rewrite(Block $block): ?array
            {
                $attrs = $block->attrs();
                if (! in_array($block->name(), $this->modules, true) || self::assigned($attrs)) {
                    return null;
                }

                return ['modulePreset' => ['p-cta']] + $attrs;
            }

            public function notes(Block $block, string $nodeId): array
            {
                return self::assigned($block->attrs()) ? [$nodeId . ': ' . PageRewriterTest::NOTE] : [];
            }

            public function concernsInstance(Block $instance): bool
            {
                return in_array(GlobalInstance::effectiveName($instance), $this->modules, true);
            }

            /** @param array<string, mixed> $attrs */
            private static function assigned(array $attrs): bool
            {
                return ($attrs['modulePreset'] ?? null) === ['p-cta'];
            }
        };
    }

    private static function query(): UsageQuery
    {
        return Mockery::mock(UsageQuery::class);
    }

    /** Runs $call with error_log() going to a temp file (Log::failure() writes there). */
    private static function quietly(Closure $call): mixed
    {
        $file = (string) tempnam(sys_get_temp_dir(), 'lit-log');
        $previous = ini_set('error_log', $file);
        try {
            return $call();
        } finally {
            ini_set('error_log', (string) $previous);
            unlink($file);
        }
    }

    public function testPreviewListsPagesAndNodesWithoutWriting(): void
    {
        $rewriter = $this->rewriter(
            [
                self::page(101, self::layout(self::BUTTON, self::TEXT, self::BUTTON)),
                self::page(102, self::layout(self::BUTTON), ['post_status' => 'publish']),
            ],
            self::report(2, [], 1, false, 3)
        );

        $preview = $rewriter->preview(self::query(), self::assign(), null);

        self::assertSame(2, $preview['pages_count']);
        self::assertSame(3, $preview['nodes_count']);
        self::assertSame([101, 102], array_column($preview['pages'], 'post_id'));
        self::assertSame('Seite 101', $preview['pages'][0]['title']);
        self::assertSame('page', $preview['pages'][0]['type']);
        self::assertSame('draft', $preview['pages'][0]['status']);
        self::assertSame('publish', $preview['pages'][1]['status']);
        self::assertSame(['s0.r0.c0.m0', 's0.r0.c0.m2'], array_column($preview['pages'][0]['nodes'], 'id'));
        self::assertSame(
            ['s0.r0.c0.m0: ' . self::NOTE, 's0.r0.c0.m2: ' . self::NOTE],
            $preview['pages'][0]['warnings']
        );
        self::assertSame([], $preview['skipped']);
        self::assertSame([], $preview['blocked_ids']);
        self::assertSame(0, $preview['blocked_hidden_count']);
        self::assertSame(3, $preview['hidden_count']);
        self::assertSame([], $this->saved, 'the dry run writes nothing');
        self::assertSame([], $this->log->records);
    }

    /** Ruling P8a like GlobalEdits: one blocked live usage stops the whole write; post_ids limit the check. */
    public function testBlockedLivePageStopsTheWholeWrite(): void
    {
        $rewriter = $this->rewriter(
            [
                self::page(101, self::layout(self::BUTTON), ['post_status' => 'publish']),
                self::page(102, self::layout(self::BUTTON), ['post_status' => 'publish']),
            ],
            self::report(2, [102], 2)
        );

        $preview = $rewriter->preview(self::query(), self::assign(), null);
        self::assertSame([102], $preview['blocked_ids']);
        self::assertSame(2, $preview['pages_count']);

        $error = self::assertToolError(
            $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY),
            'forbidden'
        );
        self::assertSame([102], $error['blocked_ids']);
        self::assertStringContainsString('IDs 102', $error['message']);
        self::assertStringContainsString('nichts wurde gespeichert', $error['message']);
        self::assertSame([], $this->saved);
        self::assertSame([], $this->log->records);

        $limited = $rewriter->apply(self::ABILITY, self::query(), self::assign(), [101], self::SUMMARY);

        self::assertSame([101], array_column($limited['saved'], 'post_id'));
        self::assertSame([[101, SaveScope::Page]], $this->saved);
    }

    /** A named live post the caller may not edit blocks the whole call (forbidden), also with post_ids. */
    public function testNamedBlockedLivePageRefusesTheCallEvenWithPostIds(): void
    {
        $rewriter = $this->rewriter(
            [
                self::page(101, self::layout(self::BUTTON), ['post_status' => 'publish']),
                self::page(102, self::layout(self::BUTTON), ['post_status' => 'publish']),
            ],
            self::report(2, [102], 2)
        );

        $preview = $rewriter->preview(self::query(), self::assign(), [101, 102]);
        self::assertSame([102], $preview['blocked_ids']);

        $error = self::assertToolError(
            $rewriter->apply(self::ABILITY, self::query(), self::assign(), [101, 102], self::SUMMARY),
            'forbidden'
        );
        self::assertSame([102], $error['blocked_ids']);
        self::assertSame([], $this->saved);
        self::assertSame([], $this->log->records);
    }

    public function testTooManyLiveUsagesAreUnsupported(): void
    {
        $rewriter = $this->rewriter(
            [self::page(101, self::layout(self::BUTTON), ['post_status' => 'publish'])],
            self::report(GlobalUsages::HARD_CAP + 1, [], GlobalUsages::HARD_CAP + 1, true)
        );

        $error = self::assertToolError($rewriter->preview(self::query(), self::assign(), null), 'unsupported');
        self::assertStringContainsString(sprintf('mehr als %d', GlobalUsages::HARD_CAP), $error['message']);
        self::assertToolError(
            $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY),
            'unsupported'
        );
        self::assertSame([], $this->saved);
    }

    /** A6: 51 pages – 50 saved, remaining 1; the next call saves the last one, remaining 0. */
    public function testWritesAtMostFiftyPagesAndTheNextCallTheRest(): void
    {
        $posts = array_map(
            static fn (int $id): WP_Post => self::page($id, self::layout(self::BUTTON)),
            range(101, 151)
        );
        $rewriter = $this->rewriter($posts);

        $preview = $rewriter->preview(self::query(), self::assign(), null);
        self::assertSame(51, $preview['pages_count']);
        self::assertCount(PageRewriter::PAGE_LIMIT, $preview['pages']);

        $first = $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);

        self::assertCount(PageRewriter::PAGE_LIMIT, $first['saved']);
        self::assertSame(['post_id' => 101, 'revision_id' => 901, 'nodes' => 1], $first['saved'][0]);
        self::assertSame(1, $first['remaining']);
        self::assertSame('Eintrag 101: s0.r0.c0.m0: ' . self::NOTE, $first['warnings'][0]);
        self::assertSame([], $first['skipped']);
        self::assertSame(range(101, 150), array_column($this->saved, 0));
        self::assertCount(PageRewriter::PAGE_LIMIT, $this->log->records);
        self::assertSame(
            [
                'ability' => self::ABILITY,
                'object_type' => 'page',
                'object_id' => '101',
                'summary' => 'Divi "Seite 101": ' . self::SUMMARY,
                'revision_id' => 901,
                'snapshot_id' => null,
                'result' => 'ok',
            ],
            $this->log->records[0]
        );
        self::assertStringContainsString('"modulePreset":["p-cta"]', (string) $posts[0]->post_content);

        $second = $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);

        self::assertSame([['post_id' => 151, 'revision_id' => 951, 'nodes' => 1]], $second['saved']);
        self::assertSame(0, $second['remaining']);
        self::assertSame([], $second['skipped']);
    }

    public function testPageWithoutChangeIsNotSavedOrCounted(): void
    {
        $rewriter = $this->rewriter([
            self::page(101, self::layout(self::TEXT)),
            self::page(102, self::layout(self::BUTTON)),
        ]);

        $preview = $rewriter->preview(self::query(), self::assign(), null);
        $result = $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);

        self::assertSame(1, $preview['pages_count']);
        self::assertSame([102], array_column($result['saved'], 'post_id'));
        self::assertSame(0, $result['remaining']);
        self::assertSame([], $result['skipped']);
        self::assertSame(['102'], array_column($this->log->records, 'object_id'));
    }

    /** R8: pages loadWritable() refuses (Divi 4, unparsable – fail-closed candidates) are skipped, not remaining. */
    public function testRefusedPagesAreSkippedWithTheLoaderMessage(): void
    {
        $rewriter = $this->rewriter([
            self::page(
                101,
                '[et_pb_section][et_pb_text]Alt[/et_pb_text][/et_pb_section]',
                ['post_status' => 'publish']
            ),
            self::page(102, '<!-- wp:divi/section --><!-- wp:divi/row -->'),
            self::page(103, self::layout(self::BUTTON)),
        ]);

        $result = self::quietly(
            fn (): array => $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY)
        );

        self::assertSame([103], array_column($result['saved'], 'post_id'));
        self::assertSame(0, $result['remaining']);
        self::assertSame([101, 102], array_column($result['skipped'], 'post_id'));
        self::assertStringContainsString('Divi-4-Inhalt', $result['skipped'][0]['reason']);
        self::assertStringContainsString('kein gültiges Block-Markup', $result['skipped'][1]['reason']);
    }

    /** Spec §6.6: a failed page keeps the pages saved before – partial_write with their revisions. */
    public function testFailedPageIsPartial(): void
    {
        $rewriter = $this->rewriter([
            self::page(101, self::layout(self::BUTTON)),
            self::page(102, self::layout(self::BUTTON)),
            self::page(103, self::layout(self::BUTTON)),
        ]);
        $this->failures = [null, null, WriteFailed::rolledBack(DiviSaver::REASON, postId: 103)];

        $result = self::quietly(
            fn () => $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY)
        );

        $error = self::assertToolError($result, 'partial_write');
        self::assertSame(
            [
                ['post_id' => 101, 'revision_id' => 901, 'nodes' => 1],
                ['post_id' => 102, 'revision_id' => 902, 'nodes' => 1],
            ],
            $error['saved']
        );
        self::assertSame(103, $error['post_id']);
        self::assertStringContainsString('Eintrag 103: ' . DiviSaver::REASON, $error['message']);
        self::assertStringContainsString('2 Einträge davor sind gespeichert', $error['message']);
        self::assertStringContainsString('Eintrag 103 blieb unverändert.', $error['message']);
        $this->log->assertRecorded(
            ['object_id' => '101', 'revision_id' => 901],
            ['object_id' => '102', 'revision_id' => 902]
        );
    }

    /** Like DiviWriter: a page the saver could not roll back is logged as partial. */
    public function testPageThatWasNotRolledBackIsLoggedAsPartial(): void
    {
        $this->log = FakeChangeLog::any();
        $rewriter = $this->rewriter([
            self::page(101, self::layout(self::BUTTON)),
            self::page(102, self::layout(self::BUTTON)),
        ]);
        $this->failures = [null, WriteFailed::partial(DiviSaver::REASON, postId: 102, revisionId: 812)];

        $result = self::quietly(
            fn () => $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY)
        );

        $error = self::assertToolError($result, 'partial_write');
        self::assertSame(812, $error['revision_id']);
        self::assertStringContainsString('1 Eintrag davor ist gespeichert', $error['message']);
        self::assertStringContainsString(
            'Eintrag 102 ist möglicherweise teilweise geändert (Stand vorher: Revision 812).',
            $error['message']
        );
        $this->log->assertRecorded(['object_id' => '101']);
        $this->log->assertPartials([
            'object_id' => '102',
            'summary' => 'Divi "Seite 102": Änderung nur teilweise zurückgenommen',
            'revision_id' => 812,
        ]);
    }

    /** Spec §5.5: an unreleased Divi before the first page is the release refusal (AbilityRegistrar). */
    public function testLockedDiviBeforeTheFirstPageIsThrown(): void
    {
        $rewriter = $this->rewriter([self::page(101, self::layout(self::BUTTON))]);
        $this->failures = [
            new DiviLocked(ReleaseMatrices::uniform(ReleaseState::Untested, '5.16.0'), [DiviFeature::PageWrite]),
        ];

        $this->expectException(DiviLocked::class);

        $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);
    }

    /** R8: a global instance is never rewritten; it is skipped with its node ID, the rest of the page is saved. */
    public function testGlobalInstanceIsSkippedAndKeptAsItIs(): void
    {
        $post = self::page(101, self::layout(self::INSTANCE, self::BUTTON));
        $rewriter = $this->rewriter([$post]);

        $preview = $rewriter->preview(self::query(), self::assign(), null);

        self::assertSame(['s0.r0.c0.m0'], array_column($preview['pages'][0]['nodes'], 'id'));
        self::assertCount(1, $preview['skipped']);
        self::assertSame(101, $preview['skipped'][0]['post_id']);
        self::assertStringStartsWith('s0.r0.c0.g0: ', $preview['skipped'][0]['reason']);

        $result = $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);

        self::assertSame([101], array_column($result['saved'], 'post_id'));
        self::assertStringContainsString(self::INSTANCE, (string) $post->post_content);
        self::assertStringContainsString('"modulePreset":["p-cta"]', (string) $post->post_content);
    }

    /** Ruling P13: a user who may see library IDs is told which entry to edit. */
    public function testGlobalInstanceReasonNamesTheEntryWhenIdsAreVisible(): void
    {
        $rewriter = $this->rewriter([self::page(101, self::layout(self::INSTANCE, self::BUTTON))]);

        $preview = $rewriter->preview(self::query(), self::assign(), null);
        $result = $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);

        self::assertSame(
            's0.r0.c0.g0: globales Modul – im Bibliothekseintrag 1059 ändern',
            $preview['skipped'][0]['reason']
        );
        self::assertSame($preview['skipped'], $result['skipped']);
    }

    /** Ruling P13: without the library right the reason names no library ID (dry run and write). */
    public function testGlobalInstanceReasonHidesTheEntryWithoutLibraryRights(): void
    {
        $loader = LibraryFixtures::loader(LibraryFixtures::access(['divi_library']));
        $rewriter = $this->rewriter([self::page(101, self::layout(self::INSTANCE, self::BUTTON))], null, [], $loader);
        self::assertFalse($loader->libraryIdsVisible());

        $preview = $rewriter->preview(self::query(), self::assign(), null);
        $result = $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);

        $expected = [['post_id' => 101, 'reason' => 's0.r0.c0.g0: globales Modul – im Divi-Builder ändern']];
        self::assertSame($expected, $preview['skipped']);
        self::assertSame($expected, $result['skipped']);
        self::assertSame([101], array_column($result['saved'], 'post_id'));
        self::assertStringNotContainsString('1059', (string) json_encode([$preview, $result]));
    }

    /** R8: library entries are usages of their own, saved with DiviWriter's scope. */
    public function testLibraryEntriesAreSavedWithTheirScope(): void
    {
        $rewriter = $this->rewriter([LibraryFixtures::item(1057), LibraryFixtures::item(1059)]);

        $result = $rewriter->apply(
            self::ABILITY,
            self::query(),
            self::assign(['divi/blurb', 'divi/text']),
            null,
            self::SUMMARY
        );

        self::assertSame([1057, 1059], array_column($result['saved'], 'post_id'));
        self::assertSame([[1057, SaveScope::LibraryItem], [1059, SaveScope::GlobalItem]], $this->saved);
        $this->log->assertRecorded(
            ['object_type' => 'et_pb_layout', 'object_id' => '1057'],
            ['object_type' => 'et_pb_layout', 'object_id' => '1059']
        );
    }

    /** Audit L2: a normal entry that pages show as instance is saved site-wide as well. */
    public function testReferencedLibraryEntryIsSavedSiteWide(): void
    {
        $rewriter = $this->rewriter([LibraryFixtures::item(1057)], null, [1057 => self::report(1)]);

        $rewriter->apply(self::ABILITY, self::query(), self::assign(['divi/blurb']), null, self::SUMMARY);

        self::assertSame([[1057, SaveScope::GlobalItem]], $this->saved);
    }

    /** P8a for the pages that show an entry: blocked → the entry is skipped, the others are saved. */
    public function testLibraryEntryShownOnBlockedPagesIsSkipped(): void
    {
        $rewriter = $this->rewriter(
            [LibraryFixtures::item(1059), self::page(101, self::layout(self::TEXT))],
            null,
            [1059 => self::report(1, [7], 1)]
        );

        $result = $rewriter->apply(self::ABILITY, self::query(), self::assign(['divi/text']), null, self::SUMMARY);

        self::assertSame([[101, SaveScope::Page]], $this->saved);
        self::assertSame([1059], array_column($result['skipped'], 'post_id'));
        self::assertStringContainsString('Bibliothekseintrag 1059', $result['skipped'][0]['reason']);
        self::assertStringContainsString('IDs 7', $result['skipped'][0]['reason']);
    }

    /** No backup copies in a bulk write: a site-wide entry without revisions is skipped. */
    public function testSiteWideEntryWithoutRevisionsIsSkipped(): void
    {
        Functions\when('wp_revisions_enabled')->justReturn(false);
        $rewriter = $this->rewriter([LibraryFixtures::item(1057), LibraryFixtures::item(1059)]);

        $result = $rewriter->apply(
            self::ABILITY,
            self::query(),
            self::assign(['divi/blurb', 'divi/text']),
            null,
            self::SUMMARY
        );

        self::assertSame([[1057, SaveScope::LibraryItem]], $this->saved);
        self::assertSame([1059], array_column($result['skipped'], 'post_id'));
        self::assertStringContainsString(
            'Revisionen sind für Bibliothekseintrag 1059 abgeschaltet',
            $result['skipped'][0]['reason']
        );
    }

    public function testPostIdsLimitTheCandidatesAndNameUnchangedIds(): void
    {
        $rewriter = $this->rewriter([
            self::page(101, self::layout(self::BUTTON)),
            self::page(102, self::layout(self::BUTTON)),
        ]);

        $preview = $rewriter->preview(self::query(), self::assign(), [102, 999]);

        self::assertSame([102], array_column($preview['pages'], 'post_id'));
        self::assertSame([['post_id' => 999, 'reason' => PageRewriter::NO_CHANGE]], $preview['skipped']);
        self::assertSame(0, $preview['hidden_count']);
    }

    /** Audit L4: candidates the caller may not read are neither loaded nor named, only counted. */
    public function testUnreadableCandidatesAreOnlyCounted(): void
    {
        $rewriter = $this->rewriter(
            [self::page(101, self::layout(self::BUTTON)), self::page(102, self::layout(self::BUTTON))],
            self::report(2, [], 0, false, 1)
        );
        Functions\when('current_user_can')->alias(
            static fn (string $cap, mixed ...$args): bool => ! ($cap === 'read_post' && ($args[0] ?? null) === 102)
        );

        $preview = $rewriter->preview(self::query(), self::assign(), null);
        $result = $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY);

        self::assertSame([101], array_column($preview['pages'], 'post_id'));
        self::assertSame([], $preview['skipped']);
        self::assertSame(1, $preview['hidden_count']);
        self::assertSame([[101, SaveScope::Page]], $this->saved);
        self::assertSame([], $result['skipped']);
        self::assertSame(1, $result['hidden_count'], 'detach must not say "all done" with unreadable usages');
    }

    /** Unreadable live usages the caller may not edit refuse the call (forbidden) as a count; preview lists them. */
    public function testUnreadableBlockedLivePagesRefuseTheCallAsACount(): void
    {
        $report = new UsageReport(2, [], 1, 2, [102], 2, false);
        $rewriter = $this->rewriter(
            [
                self::page(101, self::layout(self::BUTTON), ['post_status' => 'publish']),
                self::page(102, self::layout(self::BUTTON), ['post_status' => 'publish']),
            ],
            $report
        );

        $preview = $rewriter->preview(self::query(), self::assign(), null);
        self::assertSame([102], $preview['blocked_ids']);
        self::assertSame(2, $preview['blocked_hidden_count']);

        $error = self::assertToolError(
            $rewriter->apply(self::ABILITY, self::query(), self::assign(), null, self::SUMMARY),
            'forbidden'
        );
        self::assertSame([102], $error['blocked_ids']);
        self::assertSame(2, $error['blocked_hidden_count']);
        self::assertStringContainsString('2 Einträge, die dieses Konto nicht lesen darf', $error['message']);
        self::assertSame([], $this->saved);
        self::assertSame([], $this->log->records);
    }

    /**
     * Above HARD_CAP live usages the per-row edit check does not run (blocked stays empty): post_ids are not refused,
     * and a named live page the caller may not edit is skipped by loadWritable() instead of forbidden.
     */
    public function testPostIdsAboveTheHardCapAreNotRefusedAndAnUneditablePageIsSkipped(): void
    {
        $rewriter = $this->rewriter(
            [
                self::page(101, self::layout(self::BUTTON), ['post_status' => 'publish']),
                self::page(102, self::layout(self::BUTTON), ['post_status' => 'publish']),
            ],
            self::report(GlobalUsages::HARD_CAP + 1, [], GlobalUsages::HARD_CAP + 1, true)
        );
        Functions\when('current_user_can')->alias(
            static fn (string $cap, mixed ...$args): bool => ! ($cap === 'edit_post' && ($args[0] ?? null) === 101)
        );

        self::assertToolError($rewriter->preview(self::query(), self::assign(), null), 'unsupported');
        $preview = $rewriter->preview(self::query(), self::assign(), [101, 102]);
        $result = $rewriter->apply(self::ABILITY, self::query(), self::assign(), [101, 102], self::SUMMARY);

        self::assertSame([], $preview['blocked_ids']);
        self::assertSame([102], array_column($result['saved'], 'post_id'));
        self::assertSame([101], array_column($result['skipped'], 'post_id'));
        self::assertSame([[102, SaveScope::Page]], $this->saved);
    }
}