<?php

namespace App\Services\Qr;

use App\Models\QrCode;
use App\Models\QrScanEvent;
use App\Models\QrWallet;
use Carbon\Carbon;
use Illuminate\Http\Request;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;

class QrAnalyticsService
{
    /**
     * @return array<string, mixed>
     */
    public function summaryFor(QrCode $qrCode): array
    {
        $now = now();
        $events = QrScanEvent::query()->where('qr_code_id', $qrCode->id);

        return [
            'total_scans' => (int) $qrCode->scans_total,
            'unique_scans' => (int) $qrCode->unique_scans_total,
            'scans_7d' => (clone $events)->where('scanned_at', '>=', $now->copy()->subDays(7))->count(),
            'scans_30d' => (clone $events)->where('scanned_at', '>=', $now->copy()->subDays(30))->count(),
            'last_scanned_at' => $qrCode->last_scanned_at,
        ];
    }

    /**
     * @return Collection<int, object{date: string, total: int}>
     */
    public function dailyScans(QrCode $qrCode, int $days = 30): Collection
    {
        $start = now()->subDays($days - 1)->startOfDay();

        $rows = QrScanEvent::query()
            ->selectRaw('DATE(scanned_at) as scan_date, COUNT(*) as total')
            ->where('qr_code_id', $qrCode->id)
            ->where('scanned_at', '>=', $start)
            ->groupBy('scan_date')
            ->orderBy('scan_date')
            ->get()
            ->keyBy('scan_date');

        $series = collect();
        for ($i = 0; $i < $days; $i++) {
            $date = $start->copy()->addDays($i)->toDateString();
            $series->push((object) [
                'date' => $date,
                'total' => (int) ($rows->get($date)?->total ?? 0),
            ]);
        }

        return $series;
    }

    /**
     * @return array<int, array{label: string, total: int}>
     */
    public function breakdown(QrCode $qrCode, string $column, int $limit = 5): array
    {
        return QrScanEvent::query()
            ->select($column, DB::raw('COUNT(*) as total'))
            ->where('qr_code_id', $qrCode->id)
            ->whereNotNull($column)
            ->groupBy($column)
            ->orderByDesc('total')
            ->limit($limit)
            ->get()
            ->map(fn ($row) => [
                'label' => (string) $row->{$column},
                'total' => (int) $row->total,
            ])
            ->all();
    }

    /**
     * @return \Illuminate\Database\Eloquent\Collection<int, QrScanEvent>
     */
    public function recentScans(QrCode $qrCode, int $limit = 20)
    {
        return QrScanEvent::query()
            ->where('qr_code_id', $qrCode->id)
            ->latest('scanned_at')
            ->limit($limit)
            ->get();
    }
}