<?php

namespace App\Services\Events;

use App\Models\QrCode;
use Illuminate\Support\Collection;

class EventProgrammeService
{
    /** @return array{title: string, days: list<array<string, mixed>>}|null */
    public function snapshot(?QrCode $programme): ?array
    {
        if (! $programme || $programme->type !== QrCode::TYPE_ITINERARY) {
            return null;
        }

        $content = $programme->content();

        return [
            'title' => (string) ($content['title'] ?? $programme->label),
            'subtitle' => (string) ($content['subtitle'] ?? ''),
            'location' => (string) ($content['location'] ?? ''),
            'days' => array_values((array) ($content['days'] ?? [])),
        ];
    }

    /** @param  list<string>  $itemRefs */
    public function itemsForRefs(?array $snapshot, array $itemRefs): array
    {
        if (! $snapshot) {
            return [];
        }

        $refs = array_flip($itemRefs);
        $matched = [];

        foreach ((array) ($snapshot['days'] ?? []) as $day) {
            foreach ((array) ($day['items'] ?? []) as $item) {
                $ref = (string) ($item['ref'] ?? '');
                if ($ref !== '' && isset($refs[$ref])) {
                    $matched[] = $item;
                }
            }
        }

        return $matched;
    }

    /** @param  list<array<string, mixed>>  $items */
    public function hostsFromItems(array $items): array
    {
        return collect($items)
            ->flatMap(function ($item) {
                if (! is_array($item)) {
                    return [];
                }

                $email = strtolower(trim((string) ($item['host_speaker_email'] ?? '')));
                if ($email !== '' && filter_var($email, FILTER_VALIDATE_EMAIL)) {
                    return [$email];
                }

                $host = trim((string) ($item['host'] ?? ''));
                if ($host !== '' && filter_var($host, FILTER_VALIDATE_EMAIL)) {
                    return [$host];
                }

                if ($host !== '') {
                    return [$host];
                }

                return [];
            })
            ->unique()
            ->values()
            ->all();
    }

    /** @return list<array{email: string, name: string}> */
    public function speakerOptionsForProgramme(QrCode $programme): array
    {
        $options = [];

        foreach ($this->eventsLinkedToProgramme($programme) as $event) {
            foreach ((array) ($event->content()['speakers'] ?? []) as $speaker) {
                if (! is_array($speaker)) {
                    continue;
                }

                $email = trim((string) ($speaker['email'] ?? ''));
                $name = trim((string) ($speaker['name'] ?? ''));
                if ($email === '' || ! filter_var($email, FILTER_VALIDATE_EMAIL) || $name === '') {
                    continue;
                }

                $options[strtolower($email)] = [
                    'email' => $email,
                    'name' => $name,
                ];
            }
        }

        return array_values($options);
    }

    /** @return Collection<int, QrCode> */
    public function eventsLinkedToProgramme(QrCode $programme): Collection
    {
        if ($programme->type !== QrCode::TYPE_ITINERARY) {
            return collect();
        }

        return QrCode::query()
            ->where('user_id', $programme->user_id)
            ->where('type', QrCode::TYPE_EVENT)
            ->get()
            ->filter(fn (QrCode $event) => (int) ($event->content()['programme_qr_id'] ?? 0) === $programme->id);
    }
}