<?php

declare(strict_types=1);

namespace Modules\Helpdesk\Services;

use App\Models\User;
use Modules\Helpdesk\Models\Ticket;

final class CannedResponseRenderer
{
    public function render(string $template, Ticket $ticket, ?User $actor = null): string
    {
        $this->hydrateTicketUsers($ticket);
        $ticket->loadMissing(['status', 'priority', 'category', 'project', 'team']);
        $actor?->loadMissing('company');

        return strtr($template, [
            '{{ ticket.reference }}' => $ticket->reference,
            '{{ ticket.subject }}' => $ticket->subject,
            '{{ ticket.status }}' => (string) ($ticket->status?->name ?? ''),
            '{{ ticket.priority }}' => (string) ($ticket->priority?->name ?? ''),
            '{{ ticket.category }}' => (string) ($ticket->category?->name ?? ''),
            '{{ ticket.project }}' => (string) ($ticket->project?->title ?? ''),
            '{{ ticket.team }}' => (string) ($ticket->team?->name ?? ''),
            '{{ requester.name }}' => (string) ($ticket->owner?->name ?? ''),
            '{{ agent.name }}' => (string) ($ticket->agent?->name ?? ''),
            '{{ actor.name }}' => (string) ($actor?->name ?? ''),
            '{{ ticket.url }}' => route('helpdesk.tickets.show', ['ticket' => $ticket->getKey()]),
        ]);
    }

    /**
     * Load requester/agent with one query if the caller has not already attached them.
     */
    private function hydrateTicketUsers(Ticket $ticket): void
    {
        if ($ticket->relationLoaded('owner') && $ticket->relationLoaded('agent')) {
            return;
        }

        $userIds = collect([$ticket->user_id, $ticket->agent_id])
            ->filter()
            ->map(static fn (mixed $id): int => (int) $id)
            ->unique()
            ->values();

        if ($userIds->isEmpty()) {
            $ticket->setRelation('user', null);
            $ticket->setRelation('owner', null);
            $ticket->setRelation('agent', null);

            return;
        }

        $users = User::query()
            ->with('company')
            ->whereIn('id', $userIds)
            ->get()
            ->keyBy('id');

        $owner = $users->get((int) $ticket->user_id);
        $agent = $ticket->agent_id === null ? null : $users->get((int) $ticket->agent_id);

        $ticket->setRelation('user', $owner);
        $ticket->setRelation('owner', $owner);
        $ticket->setRelation('agent', $agent);
    }
}