<?php

namespace App\Http\Controllers\Front;

use Carbon\Carbon;
use App\Models\News;
use App\Models\NewsTag;
use App\Enums\YearsEnum;
use App\Models\Document;
use App\Enums\OrdersEnum;
use App\Models\DocumentTag;
use Illuminate\Support\Str;
use Illuminate\Support\Collection;
use App\Http\Requests\Front\PostsRequest;
use Uwil\LaravelCommon\Controllers\Controller;
use Uwil\LaravelCommon\Helpers\CollectionHelper;

class PostsController extends Controller
{
    /**
     * Extract unique years from date field in a collection.
     *
     * @param \Illuminate\Support\Collection $query
     * @param string $field
     *
     * @return \Illuminate\Support\Collection
     */
    private function getUniqueYearsFromCollection(Collection $model, string $field): Collection
    {
        return $model->pluck($field)
            ->map(fn($date) => Carbon::parse($date)->year)
            ->unique()
            ->values();
    }

    /**
     * Filter input collection to only keep items whose value exists in a reference collection.
     *
     * @param \Illuminate\Support\Collection $array1
     * @param \Illuminate\Support\Collection $array2
     * @param string|null                    $field
     *
     * @return array
     */
    function getMatchingValues(Collection $array1, Collection $array2, ?string $field = null): array
    {
        return $array2
            ->filter(fn ($item) => $array1->contains($field ? $item[$field] : $item))
            ->values()
            ->toArray();
    }

    /**
     * Build the common filters configuration for front-end listing pages
     *
     * If the type is "documents" the "order" filter is included
     *
     * @param string $type
     * @param string $category
     * @param \Illuminate\Database\Eloquent\Collection $publishedTags
     * @param \Illuminate\Database\Eloquent\Collection $model
     *
     * @return array
     */
    private function getFilters(string $type, string $category, Collection $publishedTags, Collection $model): array
    {
        $filters = [];

        $tags = collect($publishedTags)
            ->map(fn($tag) => [
                'title'    => $tag->name,
                'tag'      => $tag->slug,
                'category' => $category,
            ])
            ->values();


        $enumYears = collect(YearsEnum::toArray())
            ->map(fn($year) => YearsEnum::make((int) $year->value))
            ->map(fn($year) => [
                'title'    => trans($year->label()),
                'tag'      => Str::replace('/', '-', $year->label()),
                'value'    => $type === "news" ? explode('/', $year->label())[1] : $year->value,
                'category' => $category,
            ])
            ->sortDesc()
            ->values();

        $orders = collect(OrdersEnum::toArray())
            ->map(fn($order) => OrdersEnum::make((int) $order->value))
            ->filter(fn($orderLocal) => $orderLocal->ordersWithLocal())
            ->map(fn($orderLocal) => [
                'title'    => ucfirst(trans($orderLocal->label())),
                'tag'      => Str::slug($orderLocal->name),
                'category' => $category,
            ])
            ->values();

        /** Sort displayed years */
        $years = $this->getMatchingValues(
            $this->getUniqueYearsFromCollection($model, 'published_at'),
            $enumYears,
            'value'
        );

        if ($type === "documents") {
            $filters[] = [
                'title'  => ucfirst(__('front.news.order')),
                'name'   => 'order',
                'fields' => $orders,
            ];
        }

        $filters[] = [
            'title'  => $type === "documents" ? ucfirst(__('front.news.document')) : ucfirst(__('front.news.theme')),
            'name'   => 'tags',
            'fields' => $tags,
        ];

        $filters[] = [
            'title'  =>  $type === "documents" ? ucfirst(__('front.news.exercise')) : ucfirst(__('front.news.year')),
            'name'   => 'years',
            'fields' => $years,
        ];


        return $filters;
    }

    /**
     * Returns news in JSON format filtered by category and language
     * Optionally, the results can be further filtered by tags, and years
     *
     * @param \App\Http\Requests\Front\PostsRequest $request
     * @return \Illuminate\Http\JsonResponse
     */
    public function ajaxLoadNews(PostsRequest $request): \Illuminate\Http\JsonResponse
    {
        $data = $request->validated();
        $perPage = 9;
        $selectedFilters = [];

        $category = $data['category'];
        app()->setLocale($data['locale']);
        $locale = app()->getLocale();

        $publishedNewsTags = NewsTag::getTagsByCategoryInCurrentLocale($category);

        $newsModel = News::getPublishedNewsByCategoryInCurrentLocale($category);

        $requestedTags = collect($data['filters']['tags'] ?? '')
            ->filter()
            ->unique()
            ->values();

        $selectedTags = $publishedNewsTags->filter(fn ($tag) => $requestedTags->contains($tag->slug ?? null))
            ->map(fn ($tag) => [
                'id'       => $tag->id,
                'title'    => $tag->name,
                'tag'      => $tag->slug,
                'color'    => $tag->color,
                'category' => $category,
            ])
            ->values();

        if ($selectedTags->isNotEmpty()) {
            $newsModel = $newsModel->filter(function ($news) use ($selectedTags) {
                return $news->tags->contains(
                    fn ($tag) => $selectedTags->contains('id', $tag->id)
                );
            });

            $selectedFilters['tags'] = $selectedTags;
        }

        $selectedYears = collect($data['filters']['years'] ?? '')
            ->map(fn (string $label) => YearsEnum::makeFromLabel(Str::replace('-', '/', $label)))
            ->filter()
            ->map(fn($year) => [
                'title'    => $year->label(),
                'tag'      => Str::replace('/', '-', $year->label()),
                'value'    => explode('/', $year->label())[1],
                'category' => $category,
            ])
            ->values();

        if ($selectedYears->isNotEmpty()) {
            $newsModel = $newsModel->filter(function ($news) use ($selectedYears) {
                return $selectedYears->contains('value', $news->published_at->year);
            });

            $selectedFilters['years'] = $selectedYears;
        }

        $newsModel = $newsModel->sortByDesc('published_at');

        $filters = $this->getFilters('news', $category, $publishedNewsTags, $newsModel);

        /** Custom pagination */
        $newsModel = CollectionHelper::paginate($newsModel, $perPage);

        return response()->json([
            'pagination' => [
                'total' => $newsModel->total(),
                'nbItems' => count($newsModel->items()),
                'currentPage' => $newsModel->currentPage(),
                'lastPage' => $newsModel->lastPage(),
                'hasMore' => $newsModel->currentPage() < $newsModel->lastPage(),
            ],
            'filters' => view('components.front.posts.filters-dropdowns', ['filters' => $filters])->render(),
            'selectedFilters' => view('components.front.posts.selected-filters', ['selectedFilters' => $selectedFilters])->render(),
            'news' => view('components.front.posts.news', ['newsList' => $newsModel->items()])->render()
        ]);
    }

    /**
     * Returns documents in JSON format filtered by category and language
     * Optionally, the results can be further filtered by order, tags, and years
     *
     * @param \App\Http\Requests\Front\PostsRequest $request
     * @return \Illuminate\Http\JsonResponse
     */
    public function ajaxLoadDocuments(PostsRequest $request): \Illuminate\Http\JsonResponse
    {
        $data = $request->validated();
        $perPage = 3;
        $selectedFilters = [];

        $category = $data['category'];
        app()->setLocale($data['locale']);
        $locale = app()->getLocale();

        $publishedDocumentsTags = DocumentTag::getTagsByCategoryInCurrentLocale($category);

        $documentsModel = Document::getPublishedDocumentsByCategoryInCurrentLocale($category);

        $requestedTags = collect($data['filters']['tags'] ?? '')
            ->filter()
            ->unique()
            ->values();

        $selectedTags = $publishedDocumentsTags->filter(fn ($tag) => $requestedTags->contains($tag->slug ?? null))
            ->map(fn ($tag) => [
                'id'       => $tag->id,
                'title'    => $tag->name,
                'tag'      => $tag->slug,
                'color'    => $tag->color,
                'category' => $category,
            ])
            ->values();

        if ($selectedTags->isNotEmpty()) {
            $documentsModel = $documentsModel->filter(function ($documents) use ($selectedTags) {
                return $documents->tags->contains(
                    fn ($tag) => $selectedTags->contains('id', $tag->id)
                );
            });

            $selectedFilters['tags'] = $selectedTags;
        }

        $selectedYears = collect($data['filters']['years'] ?? '')
            ->map(fn (string $label) => YearsEnum::makeFromLabel(Str::replace('-', '/', $label)))
            ->filter()
            ->map(fn($year) => [
                'title'    => $year->label(),
                'tag'      => Str::replace('/', '-', $year->label()),
                'value'    => $year->value,
                'category' => $category,
            ])
            ->values();

        if ($selectedYears->isNotEmpty()) {
            $documentsModel = $documentsModel->filter(function ($documents) use ($selectedYears) {
                return $selectedYears->contains('value', $documents->exercice);
            });

            $selectedFilters['years'] = $selectedYears;
        }

        $selectedOrder = collect($data['filters']['order'] ?? '')
            ->map(fn (string $label) => OrdersEnum::makeFromLabel($label))
            ->filter()
            ->map(fn($order) => [
                'title'    => trans($order->label()),
                'tag'      => $order->name(),
                'category' => $category,
            ])
            ->values();

        if ($selectedOrder->isNotEmpty()) {
            $documentsModel = $selectedOrder->map->tag->first() === 'desc'
                ? $documentsModel->sortByDesc('published_at')
                : $documentsModel->sortBy('published_at');

            $selectedFilters['order'] = $selectedOrder->all();
        } else {
            $documentsModel = $documentsModel->sortByDesc('published_at');
        }

        $filters = $this->getFilters('documents', $category, $publishedDocumentsTags, $documentsModel);

        /** Custom pagination */
        $documentsModel = CollectionHelper::paginate($documentsModel, $perPage);

        return response()->json([
            'pagination' => [
                'total' => $documentsModel->total(),
                'nbItems' => count($documentsModel->items()),
                'currentPage' => $documentsModel->currentPage(),
                'lastPage' => $documentsModel->lastPage(),
                'hasMore' => $documentsModel->currentPage() < $documentsModel->lastPage(),
            ],
            'filters' => view('components.front.posts.filters-dropdowns', ['filters' => $filters])->render(),
            'selectedFilters' => view('components.front.posts.selected-filters', ['selectedFilters' => $selectedFilters])->render(),
            'news' => view('components.front.posts.documents', ['documentsList' => $documentsModel->items()])->render()
        ]);
    }
}