<?php

namespace App\Http\Controllers;

use App\Models\Category;
use App\Models\Product;
use Illuminate\Support\Collection;

class SitemapController extends Controller
{
    public function index()
    {
        $latestProductUpdate = Product::query()->where('is_active', true)->max('updated_at');
        $latestCategoryUpdate = Category::query()->where('is_active', true)->max('updated_at');
        $catalogLastmod = collect([$latestProductUpdate, $latestCategoryUpdate])
            ->filter()
            ->map(fn ($value) => $value instanceof \Carbon\CarbonInterface ? $value : \Carbon\Carbon::parse((string) $value))
            ->max();
        $catalogLastmodIso = $catalogLastmod?->toAtomString() ?? now()->toAtomString();

        $urls = collect([
            [
                'loc' => route('home'),
                'lastmod' => $catalogLastmodIso,
                'changefreq' => 'daily',
                'priority' => '1.0',
            ],
            [
                'loc' => route('catalog.index'),
                'lastmod' => $catalogLastmodIso,
                'changefreq' => 'daily',
                'priority' => '0.9',
            ],
            [
                'loc' => route('pages.about'),
                'lastmod' => now()->toAtomString(),
                'changefreq' => 'monthly',
                'priority' => '0.5',
            ],
            [
                'loc' => route('pages.contacts'),
                'lastmod' => now()->toAtomString(),
                'changefreq' => 'monthly',
                'priority' => '0.5',
            ],
            [
                'loc' => route('pages.shipping-payment'),
                'lastmod' => now()->toAtomString(),
                'changefreq' => 'monthly',
                'priority' => '0.5',
            ],
        ]);

        $categoryUrls = Category::query()
            ->where('is_active', true)
            ->get()
            ->map(function (Category $category) {
                return [
                    'loc' => route('catalog.category', $category),
                    'lastmod' => $category->updated_at?->toAtomString() ?? now()->toAtomString(),
                    'changefreq' => 'weekly',
                    'priority' => '0.8',
                ];
            });

        $productUrls = Product::query()
            ->where('is_active', true)
            ->get()
            ->map(function (Product $product) {
                return [
                    'loc' => route('products.show', $product),
                    'lastmod' => $product->updated_at?->toAtomString() ?? now()->toAtomString(),
                    'changefreq' => 'weekly',
                    'priority' => '0.7',
                ];
            });

        $allUrls = $this->mergeUrls($urls, $categoryUrls, $productUrls);

        return response()
            ->view('seo.sitemap', ['urls' => $allUrls])
            ->header('Content-Type', 'application/xml; charset=UTF-8');
    }

    private function mergeUrls(Collection ...$collections): Collection
    {
        return collect($collections)
            ->flatten(1)
            ->values();
    }
}