<?php

namespace App\Services\Link;

use App\Models\LinkClick;
use App\Models\ShortLink;
use App\Models\User;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;

class LinkAnalyticsService
{
    /** @return array{total_clicks:int,unique_clicks:int,clicks_7d:int,clicks_30d:int,links_total:int} */
    public function summaryForAccount(User $account): array
    {
        $links = ShortLink::query()->where('user_id', $account->id);
        $clicks = LinkClick::query()->whereIn('short_link_id', (clone $links)->select('id'));

        return [
            'total_clicks' => (int) (clone $links)->sum('clicks_total'),
            'unique_clicks' => (int) (clone $links)->sum('unique_clicks_total'),
            'clicks_7d' => (int) (clone $clicks)->where('clicked_at', '>=', now()->subDays(7))->count(),
            'clicks_30d' => (int) (clone $clicks)->where('clicked_at', '>=', now()->subDays(30))->count(),
            'links_total' => (int) (clone $links)->count(),
        ];
    }

    /** @return Collection<int, object{date:string,total:int}> */
    public function dailyClicksForAccount(User $account, int $days = 30): Collection
    {
        $rows = LinkClick::query()
            ->selectRaw('DATE(clicked_at) as date, COUNT(*) as total')
            ->whereIn('short_link_id', ShortLink::query()->where('user_id', $account->id)->select('id'))
            ->where('clicked_at', '>=', now()->subDays($days - 1)->startOfDay())
            ->groupBy('date')
            ->orderBy('date')
            ->get()
            ->keyBy('date');

        return collect(range(0, $days - 1))->map(function (int $offset) use ($rows, $days) {
            $date = now()->subDays($days - 1 - $offset)->toDateString();

            return (object) [
                'date' => $date,
                'total' => (int) ($rows[$date]->total ?? 0),
            ];
        });
    }

    /** @return Collection<int, array{label:string,total:int}> */
    public function topLinksForAccount(User $account, int $limit = 8): Collection
    {
        return ShortLink::query()
            ->where('user_id', $account->id)
            ->orderByDesc('clicks_total')
            ->limit($limit)
            ->get()
            ->map(fn (ShortLink $link) => [
                'label' => $link->label ?: $link->slug,
                'slug' => $link->slug,
                'total' => $link->clicks_total,
                'url' => route('user.links.show', $link),
            ]);
    }

    /** @return Collection<int, object> */
    public function recentClicksForAccount(User $account, int $limit = 15): Collection
    {
        return LinkClick::query()
            ->with('shortLink:id,slug,label')
            ->whereIn('short_link_id', ShortLink::query()->where('user_id', $account->id)->select('id'))
            ->latest('clicked_at')
            ->limit($limit)
            ->get();
    }

    /** @return Collection<int, array{label:string,total:int}> */
    public function referrersForAccount(User $account, int $limit = 8): Collection
    {
        return LinkClick::query()
            ->select('referer', DB::raw('COUNT(*) as total'))
            ->whereIn('short_link_id', ShortLink::query()->where('user_id', $account->id)->select('id'))
            ->whereNotNull('referer')
            ->where('referer', '!=', '')
            ->groupBy('referer')
            ->orderByDesc('total')
            ->limit($limit)
            ->get()
            ->map(fn ($row) => [
                'label' => $this->refererLabel((string) $row->referer),
                'total' => (int) $row->total,
            ]);
    }

    private function refererLabel(string $referer): string
    {
        $host = parse_url($referer, PHP_URL_HOST);

        return is_string($host) && $host !== '' ? $host : $referer;
    }
}