<?php

declare(strict_types=1);

namespace LIT\MCP\Integrations\Divi\Pages;

use LIT\MCP\Abilities\Ability;
use LIT\MCP\Abilities\Annotations;
use LIT\MCP\Abilities\Errors;
use LIT\MCP\Abilities\JsonMap;
use LIT\MCP\Abilities\Rev;
use LIT\MCP\Integrations\Divi\BlockTree\AttrMap;
use LIT\MCP\Integrations\Divi\BlockTree\NodeIndex;
use LIT\MCP\Integrations\Divi\BlockTree\NodeSummary;
use LIT\MCP\Integrations\Divi\Design\DesignSystemReader;
use LIT\MCP\Integrations\Divi\Schema\ShortformMap;
use WP_Error;

defined('ABSPATH') || exit;

/**
 * lit/divi-node-get: all attributes of one node in the full form (spec §5.4, §5.7) –
 * attribute path => breakpoint map – plus the current short-form values.
 */
final class DiviNodeGetAbility implements Ability
{
    public function __construct(private DiviPageLoader $loader, private DesignSystemReader $design)
    {
    }

    public function name(): string
    {
        return 'lit/divi-node-get';
    }

    public function label(): string
    {
        return 'Divi-Knoten lesen';
    }

    public function description(): string
    {
        return 'Liest einen Knoten der Divi-Seite vollständig: attrs als Attributpfad → Werte je Breakpoint '
            . '(Vollform, z. B. "title.decoration.font.font": {"desktop": {"value": {…}}}), die Kurzform-Werte, '
            . 'Presets und die IDs der Kinder. Pfad-IDs aus lit-divi-outline. Werte wie $variable(…)$ (globale '
            . 'Farben, Variablen, dynamische Inhalte) werden unverändert angezeigt, beim Schreiben aber erneut '
            . 'geprüft, nie ungeprüft übernommen.';
    }

    public function inputSchema(): array
    {
        return [
            'type' => 'object',
            'properties' => [
                'post_id' => ['type' => 'integer', 'minimum' => 1],
                'id' => ['type' => 'string', 'description' => 'Pfad-ID aus lit-divi-outline, z. B. "s0.r0.c1.m2".'],
            ],
            'required' => ['post_id', 'id'],
            'additionalProperties' => false,
        ];
    }

    public function outputSchema(): ?array
    {
        return [
            'type' => 'object',
            'properties' => [
                'post_id' => ['type' => 'integer'],
                'tree_rev' => ['type' => 'string'],
                'rev' => ['type' => 'string'],
                'id' => ['type' => 'string'],
                'parent' => ['type' => ['string', 'null']],
                'type' => ['type' => 'string'],
                'label' => ['type' => 'string'],
                'editable' => ['type' => 'boolean'],
                'attrs' => ['type' => 'object'],
                'shortform' => ['type' => 'object'],
                'presets' => [
                    'type' => 'array',
                    'items' => [
                        'type' => 'object',
                        'properties' => ['id' => ['type' => 'string'], 'name' => ['type' => 'string']],
                        'required' => ['id', 'name'],
                    ],
                ],
                'builder_version' => ['type' => ['string', 'null']],
                'children' => ['type' => 'array', 'items' => ['type' => 'string']],
                'global' => ['type' => ['object', 'null']],
            ],
            'required' => ['post_id', 'tree_rev', 'rev', 'id', 'type', 'editable', 'attrs', 'shortform', 'children'],
        ];
    }

    public function annotations(): array
    {
        return Annotations::read();
    }

    public function isDirect(): bool
    {
        return true;
    }

    public function permission(array $input): bool|WP_Error
    {
        $page = $this->loader->load($input['post_id'] ?? null, false);

        return $page instanceof WP_Error ? $page : true;
    }

    public function execute(array $input): mixed
    {
        $page = $this->loader->load($input['post_id'] ?? null, false);
        if ($page instanceof WP_Error) {
            return $page;
        }

        $id = is_string($input['id'] ?? null) ? $input['id'] : '';
        if (preg_match(NodeIndex::ID_PATTERN, $id) !== 1) {
            return Errors::invalidInput('id ist keine Pfad-ID.', ['id' => 'z. B. "s0.r1.c0.m2"']);
        }

        $block = $page->index->find($id);
        if ($block === null) {
            return DiviErrors::unknownNode($id, $page->post);
        }

        $names = $this->design->read()->presetNames();
        $editable = $block->isDivi() && ! $block->isOpaque();
        $version = $block->attrs()['builderVersion'] ?? null;

        $global = NodeSummary::globalRef($block);
        if ($global !== null && $this->loader->libraryIdsVisible()) {
            $global['hint'] = sprintf(
                'Globales Modul: Inhalt im Bibliothekseintrag %s bearbeiten (lit-divi-outline mit post_id %s); '
                    . 'jede Änderung dort wirkt auf alle Seiten mit diesem Modul.',
                $global['id'],
                $global['id']
            );
        } elseif ($global !== null) {
            // Ruling P13: which entry is shown stays unknown without library access (AttrMap::flatten
            // already leaves globalModule/globalParent out of attrs).
            $global = [
                'id' => null,
                'block_name' => $global['block_name'],
                'hint' => 'Globales Modul aus der Divi-Bibliothek – nur lesbar; dieses Konto hat keinen Zugang zur '
                    . 'Divi-Bibliothek.',
            ];
        }

        return [
            'post_id' => (int) $page->post->ID,
            'tree_rev' => $page->treeRev(),
            'rev' => Rev::ofPost($page->post),
            'id' => $id,
            'parent' => $page->index->parentId($block),
            'type' => $block->isDivi() ? $block->shortName() : $block->name(),
            'label' => NodeSummary::label($block),
            'editable' => $editable,
            'attrs' => JsonMap::of(AttrMap::flatten($block->attrs())),
            'shortform' => JsonMap::of(ShortformMap::values($block->shortName(), $block->attrs())),
            'presets' => array_map(
                static fn (string $presetId): array => ['id' => $presetId, 'name' => $names[$presetId] ?? ''],
                NodeSummary::presetIds($block)
            ),
            'builder_version' => is_string($version) ? $version : null,
            'children' => $editable
                ? array_values(array_filter(array_map([$page->index, 'idOf'], $block->children())))
                : [],
            'global' => $global,
        ];
    }
}