<?php

namespace App\Services\PressRelease;

use App\Enums\PressReleaseStatus;
use App\Mail\PressReleasePublished;
use App\Mail\PressReleaseRejected;
use App\Models\AdminPreset;
use App\Models\PressRelease;
use App\Models\PressReleaseStatusLog;
use App\Services\Admin\AdminPerformanceCache;
use Illuminate\Support\Carbon;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Mail;

/**
 * Kapselt Statusübergänge für Pressemitteilungen inkl. Benachrichtigungs-Mails.
 *
 * Jede Methode verändert exklusiv den Status und versendet optional eine Mail
 * an den Autor (User). Die Caller-Schicht (Volt, Command, API) muss nur noch
 * diese Methoden aufrufen – keine Mail-Logik außerhalb dieser Klasse.
 */
class PressReleaseService
{
    public function __construct(private readonly BlacklistService $blacklist) {}

    public function submitForReview(PressRelease $pressRelease): void
    {
        $this->assertStatus($pressRelease, [PressReleaseStatus::Draft, PressReleaseStatus::Rejected]);

        $previous = $pressRelease->status;

        if ($word = $this->blacklist->findInPressRelease($pressRelease)) {
            $reason = sprintf('Automatische Ablehnung: unzulässiges Wort "%s" gefunden.', $word);

            $pressRelease->update(['status' => PressReleaseStatus::Rejected->value]);
            $this->logStatusChange($pressRelease, $previous, PressReleaseStatus::Rejected, $reason, 'blacklist');
            $this->notifyAuthor($pressRelease, 'rejected', $reason);

            throw new BlacklistViolationException($reason, $word);
        }

        $pressRelease->update(['status' => PressReleaseStatus::Review->value]);
        $this->logStatusChange($pressRelease, $previous, PressReleaseStatus::Review, null, 'customer');
    }

    public function publish(PressRelease $pressRelease, string $source = 'admin'): void
    {
        $this->assertStatus($pressRelease, [PressReleaseStatus::Review]);

        $previous = $pressRelease->status;

        if ($word = $this->blacklist->findInPressRelease($pressRelease)) {
            $reason = sprintf('Automatische Ablehnung: unzulässiges Wort "%s" gefunden.', $word);

            $pressRelease->update(['status' => PressReleaseStatus::Rejected->value]);
            $this->logStatusChange($pressRelease, $previous, PressReleaseStatus::Rejected, $reason, 'blacklist');
            $this->notifyAuthor($pressRelease, 'rejected', $reason);

            throw new BlacklistViolationException($reason, $word);
        }

        $pressRelease->update([
            'status' => PressReleaseStatus::Published->value,
            'published_at' => $this->resolvePublishedAt($pressRelease),
        ]);

        $this->logStatusChange($pressRelease, $previous, PressReleaseStatus::Published, null, $source);
        $this->notifyAuthor($pressRelease, 'published');
    }

    /**
     * Bestimmt das wirksame `published_at` einer PM.
     *
     * Reihenfolge:
     * 1. Bereits gesetztes `published_at` bleibt erhalten (z.B. Re-Publish)
     * 2. `scheduled_at` (geplanter Veröffentlichungstermin) hat Vorrang vor "jetzt"
     * 3. `embargo_at` (Sperrfrist) verschiebt zusätzlich nach hinten — egal ob
     *    Scheduled vorhanden ist oder nicht
     * 4. Fallback: now()
     *
     * Damit wirken sowohl Scheduling als auch Embargo automatisch über den
     * vorhandenen Sichtbarkeits-Filter `where(published_at <= now())` im
     * öffentlichen Listing.
     */
    private function resolvePublishedAt(PressRelease $pressRelease): Carbon
    {
        if ($pressRelease->published_at) {
            return $pressRelease->published_at;
        }

        $base = $pressRelease->scheduled_at ?: now();

        if ($pressRelease->embargo_at && $pressRelease->embargo_at->greaterThan($base)) {
            return $pressRelease->embargo_at;
        }

        return $base;
    }

    public function reject(PressRelease $pressRelease, ?string $reason = null): void
    {
        $this->assertStatus($pressRelease, [PressReleaseStatus::Review]);

        $previous = $pressRelease->status;

        $pressRelease->update(['status' => PressReleaseStatus::Rejected->value]);

        $this->logStatusChange($pressRelease, $previous, PressReleaseStatus::Rejected, $reason, 'admin');
        $this->notifyAuthor($pressRelease, 'rejected', $reason);
    }

    public function backToDraft(PressRelease $pressRelease): void
    {
        $this->assertStatus($pressRelease, [PressReleaseStatus::Review, PressReleaseStatus::Rejected]);

        $previous = $pressRelease->status;

        $pressRelease->update(['status' => PressReleaseStatus::Draft->value]);
        $this->logStatusChange($pressRelease, $previous, PressReleaseStatus::Draft, null, 'admin');
    }

    public function archive(PressRelease $pressRelease): void
    {
        $this->assertStatus($pressRelease, [PressReleaseStatus::Published]);

        $previous = $pressRelease->status;

        $pressRelease->update(['status' => PressReleaseStatus::Archived->value]);
        $this->logStatusChange($pressRelease, $previous, PressReleaseStatus::Archived, null, 'admin');
    }

    public function changeStatusFromAdmin(PressRelease $pressRelease, PressReleaseStatus $status, ?string $reason = null): void
    {
        $previous = $pressRelease->status;

        $pressRelease->update([
            'status' => $status->value,
            'published_at' => $status === PressReleaseStatus::Published
                ? ($pressRelease->published_at ?? now())
                : $pressRelease->published_at,
        ]);

        if ($previous !== $status) {
            $this->logStatusChange($pressRelease, $previous, $status, $reason, 'admin');
        }
    }

    public function deleteFromAdmin(PressRelease $pressRelease): void
    {
        if ($pressRelease->status === PressReleaseStatus::Published) {
            $pressRelease->update([
                'status' => PressReleaseStatus::Archived->value,
                'text' => AdminPreset::activeValue(
                    AdminPreset::PRESS_RELEASE_DELETED_PUBLISHED_TEXT,
                    "Diese Pressemitteilung wurde entfernt.\n\nDer Inhalt ist nicht mehr verfuegbar."
                ),
                'keywords' => null,
                'backlink_url' => null,
                'no_export' => true,
            ]);

            return;
        }

        $pressRelease->delete();
    }

    /**
     * @param  PressReleaseStatus[]  $allowed
     */
    private function assertStatus(PressRelease $pressRelease, array $allowed): void
    {
        if (! in_array($pressRelease->status, $allowed, true)) {
            $allowedValues = implode(', ', array_map(fn ($s) => $s->value, $allowed));
            $currentStatus = $pressRelease->status instanceof PressReleaseStatus
                ? $pressRelease->status->value
                : (string) $pressRelease->status;

            throw new \LogicException(
                "Statusübergang nicht erlaubt. Aktueller Status: {$currentStatus}, erwartet: {$allowedValues}"
            );
        }
    }

    private function logStatusChange(
        PressRelease $pressRelease,
        ?PressReleaseStatus $from,
        PressReleaseStatus $to,
        ?string $reason,
        string $source,
    ): void {
        PressReleaseStatusLog::query()->create([
            'press_release_id' => $pressRelease->id,
            'changed_by_user_id' => Auth::id(),
            'from_status' => $from?->value,
            'to_status' => $to->value,
            'reason' => $reason,
            'source' => $source,
            'created_at' => now(),
        ]);

        Cache::forget(AdminPerformanceCache::PressReleaseStats);
        Cache::forget(AdminPerformanceCache::PressReleaseReviewCount);
    }

    private function notifyAuthor(PressRelease $pressRelease, string $event, ?string $reason = null): void
    {
        $user = $pressRelease->user;

        if (! $user || ! $user->email) {
            return;
        }

        $mailable = match ($event) {
            'published' => new PressReleasePublished($user, $pressRelease),
            'rejected' => new PressReleaseRejected($user, $pressRelease, $reason),
            default => null,
        };

        if ($mailable) {
            Mail::to($user->email)->queue($mailable);
        }
    }
}