<?php

namespace Modules\AssetExchange\Services;

use App\Business;
use Carbon\Carbon;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Schema;
use Modules\AssetExchange\Models\PriceInquiry;
use Modules\AssetExchange\Models\ResearchTask;
use Modules\AssetExchange\Utils\AssetExchangeUtil;

class InquirySlaService
{
    public function __construct(
        protected AssetExchangeUtil $aexUtil
    ) {
    }

    public function slaSettings(int $businessId): array
    {
        $settings = $this->aexUtil->getAexSettings($businessId);

        return [
            'inquiry_sla_hours' => max(1, (int) ($settings['inquiry_sla_hours'] ?? 48)),
            'inquiry_sla_warning_percent' => min(99, max(1, (int) ($settings['inquiry_sla_warning_percent'] ?? 75))),
            'research_task_sla_days' => max(1, (int) ($settings['research_task_sla_days'] ?? 7)),
        ];
    }

    /**
     * @return 'ok'|'warning'|'overdue'|'breached'|'na'
     */
    public function inquirySlaStatus(PriceInquiry $inquiry, ?array $sla = null): string
    {
        if (! in_array($inquiry->status, ['sent', 'partial'], true)) {
            return 'na';
        }

        $sla = $sla ?? $this->slaSettings((int) $inquiry->business_id);
        $now = now();

        if ($inquiry->due_date && $inquiry->due_date->lt($now->copy()->startOfDay())) {
            return 'overdue';
        }

        $sentAt = $this->resolveSentAt($inquiry);
        if (! $sentAt) {
            return 'na';
        }

        $deadline = $sentAt->copy()->addHours($sla['inquiry_sla_hours']);
        $warningAt = $sentAt->copy()->addHours(
            (int) floor($sla['inquiry_sla_hours'] * ($sla['inquiry_sla_warning_percent'] / 100))
        );

        $pendingSuppliers = $inquiry->recipients
            ? $inquiry->recipients->where('recipient_type', 'supplier')->where('status', 'pending')->count()
            : 0;

        if ($pendingSuppliers === 0) {
            return 'ok';
        }

        if ($now->gte($deadline)) {
            return 'breached';
        }

        if ($now->gte($warningAt)) {
            return 'warning';
        }

        return 'ok';
    }

    public function snapshot(Business $business): array
    {
        if (! Schema::hasTable('aex_price_inquiries')) {
            return [
                'inquiry_breached' => 0,
                'inquiry_warning' => 0,
                'inquiry_overdue_due' => 0,
                'research_overdue' => 0,
                'urgent_items' => [],
            ];
        }

        $sla = $this->slaSettings($business->id);
        $inquiries = PriceInquiry::where('business_id', $business->id)
            ->whereIn('status', ['sent', 'partial'])
            ->with(['listing', 'recipients'])
            ->orderByDesc('updated_at')
            ->limit(200)
            ->get();

        $breached = 0;
        $warning = 0;
        $overdueDue = 0;
        $urgent = collect();

        foreach ($inquiries as $inquiry) {
            $status = $this->inquirySlaStatus($inquiry, $sla);
            if ($status === 'breached') {
                $breached++;
            } elseif ($status === 'warning') {
                $warning++;
            } elseif ($status === 'overdue') {
                $overdueDue++;
            }

            if (in_array($status, ['breached', 'overdue', 'warning'], true)) {
                $urgent->push([
                    'type' => 'inquiry',
                    'id' => $inquiry->id,
                    'code' => $inquiry->inquiry_code,
                    'title' => $inquiry->title,
                    'listing' => $inquiry->listing?->title,
                    'sla_status' => $status,
                    'url' => action([\Modules\AssetExchange\Http\Controllers\PriceInquiryController::class, 'show'], [$inquiry->id]),
                ]);
            }
        }

        $researchOverdue = 0;
        if (Schema::hasTable('aex_research_tasks')) {
            $researchOverdue = ResearchTask::where('business_id', $business->id)
                ->whereNotIn('status', ['completed', 'cancelled'])
                ->whereDate('due_date', '<', now()->toDateString())
                ->count();
        }

        return [
            'inquiry_breached' => $breached,
            'inquiry_warning' => $warning,
            'inquiry_overdue_due' => $overdueDue,
            'research_overdue' => $researchOverdue,
            'urgent_items' => $urgent->take(15)->values()->all(),
            'sla' => $sla,
        ];
    }

    public function applyUrgentFilter($query, string $filter, int $businessId)
    {
        if ($filter !== 'urgent') {
            return $query;
        }

        $sla = $this->slaSettings($businessId);
        $ids = PriceInquiry::where('business_id', $businessId)
            ->whereIn('status', ['sent', 'partial'])
            ->with('recipients')
            ->get()
            ->filter(fn ($inq) => in_array($this->inquirySlaStatus($inq, $sla), ['breached', 'overdue', 'warning'], true))
            ->pluck('id')
            ->all();

        return $query->whereIn('id', $ids ?: [0]);
    }

    protected function resolveSentAt(PriceInquiry $inquiry): ?Carbon
    {
        if ($inquiry->relationLoaded('recipients')) {
            $sent = $inquiry->recipients->whereNotNull('sent_at')->min('sent_at');
            if ($sent) {
                return Carbon::parse($sent);
            }
        }

        return $inquiry->updated_at ? Carbon::parse($inquiry->updated_at) : null;
    }
}