<?php

namespace App\Services\Meet;

use App\Models\QrCode;
use App\Models\User;
use Illuminate\Support\Str;

class EventMeetRoomLinkService
{
    public function __construct(private readonly EventMeetSyncService $sync) {}

    /**
     * @return list<array<string, mixed>>
     */
    public function linkableEvents(User $owner): array
    {
        return QrCode::query()
            ->where('user_id', $owner->id)
            ->where('type', QrCode::TYPE_EVENT)
            ->orderByDesc('updated_at')
            ->get()
            ->filter(function (QrCode $event) {
                $format = (string) ($event->content()['format'] ?? 'in_person');

                return in_array($format, ['virtual', 'hybrid'], true);
            })
            ->map(fn (QrCode $event) => $this->summarizeEvent($event))
            ->values()
            ->all();
    }

    /**
     * @param  array<string, mixed>  $payload
     * @return array<string, mixed>
     */
    public function linkRoom(User $owner, QrCode $event, array $payload): array
    {
        abort_unless($event->user_id === $owner->id, 403);
        abort_unless($event->type === QrCode::TYPE_EVENT, 422);

        $format = (string) ($event->content()['format'] ?? 'in_person');
        abort_unless(in_array($format, ['virtual', 'hybrid'], true), 422, 'Only virtual or hybrid events can be linked.');

        $roomUuid = trim((string) ($payload['meet_room_uuid'] ?? ''));
        $roomType = in_array($payload['meet_room_type'] ?? '', ['town_hall', 'webinar'], true)
            ? (string) $payload['meet_room_type']
            : 'town_hall';
        abort_unless($roomUuid !== '', 422, 'meet_room_uuid is required.');

        $joinUrl = trim((string) ($payload['join_url'] ?? ''));
        $title = trim((string) ($payload['title'] ?? $event->label ?? 'Virtual session'));
        $sessionId = trim((string) ($payload['virtual_session_id'] ?? ''));

        $content = $event->content();
        $sessions = array_values(array_filter(
            (array) ($content['virtual_sessions'] ?? []),
            fn ($session) => is_array($session),
        ));

        $matchedIndex = null;
        if ($sessionId !== '') {
            foreach ($sessions as $index => $session) {
                if ((string) ($session['id'] ?? '') === $sessionId) {
                    $matchedIndex = $index;
                    break;
                }
            }
        }

        if ($matchedIndex === null) {
            foreach ($sessions as $index => $session) {
                $existingUuid = trim((string) ($session['meet_room_uuid'] ?? ''));
                $existingType = (string) ($session['meet_room_type'] ?? 'town_hall');
                if ($existingUuid === '' && $existingType === $roomType) {
                    $matchedIndex = $index;
                    break;
                }
            }
        }

        if ($matchedIndex === null) {
            $sessionId = $sessionId !== '' ? $sessionId : 'vs-'.Str::lower(Str::random(12));
            $sessions[] = [
                'id' => $sessionId,
                'title' => $title,
                'meet_room_type' => $roomType,
                'scheduled_at' => $payload['scheduled_at'] ?? $content['starts_at'] ?? null,
                'duration_minutes' => max(15, (int) ($payload['duration_minutes'] ?? 60)),
            ];
            $matchedIndex = count($sessions) - 1;
        } else {
            $sessionId = (string) ($sessions[$matchedIndex]['id'] ?? $sessionId);
        }

        $sessions[$matchedIndex] = array_merge($sessions[$matchedIndex], [
            'id' => $sessionId,
            'title' => $title !== '' ? $title : (string) ($sessions[$matchedIndex]['title'] ?? 'Virtual session'),
            'meet_room_type' => $roomType,
            'meet_room_uuid' => $roomUuid,
            'join_url' => $joinUrl !== '' ? $joinUrl : ($sessions[$matchedIndex]['join_url'] ?? null),
            'scheduled_at' => $payload['scheduled_at'] ?? $sessions[$matchedIndex]['scheduled_at'] ?? null,
            'duration_minutes' => max(15, (int) ($payload['duration_minutes'] ?? ($sessions[$matchedIndex]['duration_minutes'] ?? 60))),
        ]);

        $payloadData = (array) ($event->payload ?? []);
        $payloadData['content'] = array_merge($content, ['virtual_sessions' => $sessions]);
        $event->payload = $payloadData;
        $event->save();

        $event = $this->sync->sync($event->fresh(), $owner);

        return array_merge($this->summarizeEvent($event), [
            'entity_id' => $sessionId,
            'meet_room_uuid' => $roomUuid,
            'join_url' => $joinUrl,
        ]);
    }

    /** @return array<string, mixed> */
    private function summarizeEvent(QrCode $event): array
    {
        $content = $event->content();
        $sessions = collect((array) ($content['virtual_sessions'] ?? []))
            ->filter(fn ($session) => is_array($session))
            ->map(fn (array $session) => [
                'id' => (string) ($session['id'] ?? ''),
                'title' => (string) ($session['title'] ?? ''),
                'meet_room_type' => (string) ($session['meet_room_type'] ?? 'town_hall'),
                'meet_room_uuid' => ($uuid = trim((string) ($session['meet_room_uuid'] ?? ''))) !== '' ? $uuid : null,
                'scheduled_at' => $session['scheduled_at'] ?? null,
                'duration_minutes' => (int) ($session['duration_minutes'] ?? 60),
            ])
            ->values()
            ->all();

        return [
            'id' => $event->id,
            'title' => (string) ($content['title'] ?? $event->label ?? 'Event'),
            'format' => (string) ($content['format'] ?? 'in_person'),
            'short_code' => $event->short_code,
            'registration_url' => $event->publicUrl(),
            'admin_url' => url('/events/'.$event->id.'/attendees'),
            'edit_url' => url('/events/'.$event->id),
            'virtual_sessions' => $sessions,
        ];
    }
}