<?php

namespace App\Modules\Client\Resources;

use App\Modules\CustomField\Models\CustomFieldDefinition;
use Illuminate\Http\Request;
use Illuminate\Http\Resources\Json\JsonResource;
use Illuminate\Support\Carbon;

class ClientResource extends JsonResource
{
    public function toArray(Request $request): array
    {
        return [
            'id' => $this->id,
            'client_number' => $this->client_number,
            'name' => $this->name,
            'notes' => $this->notes ?? [],
            'created_at' => $this->created_at->toISOString(),
            'updated_at' => $this->updated_at->toISOString(),
            // List/search endpoints load these via withCount/withMax; absent on
            // the detail endpoint, so guard before exposing them.
            'history_count' => $this->whenNotNull($this->history_entries_count),
            'last_history_at' => $this->when(
                $this->history_entries_count !== null,
                fn () => $this->history_entries_max_created_at
                    ? Carbon::parse($this->history_entries_max_created_at)->toISOString()
                    : null,
            ),
            // Only present on the detail endpoint (where the relation is eager
            // loaded); omitted from list responses to avoid per-row queries.
            'custom_fields' => $this->when(
                $this->resource->relationLoaded('customFieldValues'),
                fn () => $this->buildCustomFields(),
            ),
        ];
    }

    /**
     * Merge every active field definition (ordered) with this client's value,
     * so unset fields still render with an empty state.
     *
     * @return array<int, array<string, mixed>>
     */
    private function buildCustomFields(): array
    {
        $valuesByDefinition = $this->customFieldValues->keyBy('custom_field_definition_id');

        return CustomFieldDefinition::orderBy('sort_order')->orderBy('id')->get()
            ->map(function (CustomFieldDefinition $definition) use ($valuesByDefinition) {
                $value = $valuesByDefinition->get($definition->id);

                return [
                    'definition_id' => $definition->id,
                    'key' => $definition->key,
                    'label' => $definition->label,
                    'type' => $definition->type->value,
                    'options' => $definition->options ?? [],
                    'is_required' => $definition->is_required,
                    'value' => $value?->value,
                    'author_name' => $value?->author?->name,
                    'updated_at' => $value?->updated_at?->toISOString(),
                ];
            })
            ->all();
    }
}