<?php

namespace App\Services;

use App\Models\BlogPost;
use App\Models\Recipe;
use App\Models\User;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Collection;

class FeedService
{
    public static function showActualFeed(): Collection
    {
        $dateMax = Recipe::max('created_at');
        $dateMin = Carbon::parse($dateMax)->subDays(10);

        $sql = <<<'EOF'
                    SELECT
                        p.id,
                        p.title,
                        (
                            (p.likes_count + p.comments_count) /
                            ((UNIX_TIMESTAMP(GREATEST(p.created_at,
                                COALESCE((SELECT MAX(l.created_at) FROM blog_post_likes l WHERE l.blog_post_id = p.id), p.created_at),
                                COALESCE((SELECT MAX(c.created_at) FROM blog_post_comments c WHERE c.blog_post_id = p.id), p.created_at)
                                )) - UNIX_TIMESTAMP(p.created_at))/60 + 1
                            ) ^ 1.8
                        ) AS popularity
                    FROM
                        (SELECT
                            `blog_posts`.id,
                                blog_posts.title,
                                blog_posts.created_at,
                                COUNT(blog_post_comments.id) AS comments_count,
                                COUNT(blog_post_likes.id) AS likes_count
                        FROM
                            `blog_posts`
                        LEFT JOIN blog_post_comments ON blog_post_comments.blog_post_id = blog_posts.id
                        LEFT JOIN blog_post_likes ON blog_post_likes.blog_post_id = blog_posts.id
                        GROUP BY blog_posts.id) p
                    ORDER BY popularity DESC;
            EOF;

        $hotBlogPosts = collect(
            DB::select($sql)
        )
            ->map(fn($post) => BlogPost::find($post->id))
            ->take(16)
            ->chunk(4);

        $newbiesBlogPosts = User::orderBy('created_at', 'desc')
            ->withCount('author_of_blog_post')
            ->get()
            ->filter(fn($u) => $u->author_of_blog_post_count > 0)
            ->take(4)
            ->pluck('id')
            ->map(fn($id) => User::find($id)->author_of_blog_post()->limit(2)->get())
            ->flatten()
            ->random();

        $randomRecipe = Recipe::where('created_at', '>=', $dateMin)
            ->where('created_at', '<=', $dateMax)
            ->inRandomOrder()
            ->limit(2)
            ->get();

        $firstCollection = collect([$hotBlogPosts->first(), $newbiesBlogPosts->first()]);
        $secondCollection = collect([$hotBlogPosts->skip(1)->first(), $newbiesBlogPosts->skip(1)->first()]);

        return $firstCollection->concat($secondCollection)->filter(fn($el) => !is_null($el) && $el->id);

        // $firstCollection = $hotBlogPosts->first()->push($newbiesBlogPosts->first())->push($randomRecipe->first());
        // $secondCollection = $hotBlogPosts->skip(1)->first()->push($newbiesBlogPosts->skip(1)->first())->push($randomRecipe->skip(1)->first());

        // return $firstCollection->concat($secondCollection)->filter(fn ($el) => ! is_null($el) && $el->id);
    }
}