<?php

declare(strict_types=1);

namespace LIT\MCP\Integrations\Divi\Design;

use Closure;
use LIT\MCP\Integrations\Divi\Release\DiviFeature;
use WP_Error;

defined('ABSPATH') || exit;

/**
 * Restores a snapshot of the presets (Etappe 4a): the snapshot replaces the whole inventory (presets missing in it are
 * removed); without unfiltered_html it is refused while the snapshot or the current inventory holds HTML/CSS that
 * Divi would strip (final review I-2).
 */
final class PresetRestorePlanner implements RestorePlanner
{
    private const MARKUP = 'Der Snapshot oder der aktuelle Bestand enthält Presets mit HTML/CSS, das beim Speichern '
        . 'ohne das Recht unfiltered_html verloren ginge; nichts wurde gespeichert.';

    /** @param (Closure(): bool)|null $unfiltered Whether the user may save unfiltered HTML (DesignRights). */
    public function __construct(private DesignSystemWriter $writer, private ?Closure $unfiltered = null)
    {
        $this->unfiltered ??= DesignRights::unfilteredHtml();
    }

    public function area(): string
    {
        return 'presets';
    }

    public function designArea(): DesignArea
    {
        return new PresetArea($this->writer);
    }

    public function rights(): ?WP_Error
    {
        return DesignRights::presets($this->writer);
    }

    /** Writes the presets (PresetWrite), reading them first (DesignRead). */
    public function features(): array
    {
        return [DiviFeature::DesignRead, DiviFeature::PresetWrite];
    }

    public function plan(array $current, array $snapshot, string $snapshotId): DesignPlan|WP_Error
    {
        $before = PresetBook::fromDivi($current);
        $after = PresetBook::fromDivi($snapshot);
        $refusal = DesignRights::markup(
            $this->unfiltered,
            array_merge($before->markupOutside([]), $after->markupOutside([])),
            self::MARKUP
        );
        if ($refusal !== null) {
            return $refusal;
        }
        $diff = PresetDiff::between($before, $after);

        return new DesignPlan(
            $after->data(),
            $diff,
            sprintf('Snapshot %s wiederherstellen – %s', $snapshotId, PresetDiff::summary($diff)),
            null,
            ['Seiten, die Presets verwenden, die es im Snapshot nicht gibt, behalten den Verweis; das Modul fällt '
                . 'dann auf das Standard-Preset zurück.'],
            true
        );
    }
}