<?php

namespace App\Exports;

use App\Models\Department;
use App\Models\User;
use Illuminate\Support\Carbon;
use Illuminate\Support\Collection;

class DutyReportExport
{
    private const RU_MONTHS = [
        1 => 'январь', 2 => 'февраль', 3 => 'март', 4 => 'апрель',
        5 => 'май', 6 => 'июнь', 7 => 'июль', 8 => 'август',
        9 => 'сентябрь', 10 => 'октябрь', 11 => 'ноябрь', 12 => 'декабрь',
    ];

    public function __construct(
        protected array $patients,
        protected array $dateRange,
        protected User $user,
        protected Department $department,
        protected string $reportName = 'Отчёт дежурного врача по приёмному покою и отделению',
    ) {}

    /**
     * Данные для Blade-шаблона PDF-отчёта.
     */
    public function toViewData(): array
    {
        $patients = collect($this->patients);
        $endDate = Carbon::parse($this->dateRange[1]);

        return [
            'title' => sprintf('%s «%s»', $this->reportName, $this->department->name_full ?? $this->department->name_short),
            'day' => $endDate->format('d'),
            'month' => self::RU_MONTHS[(int) $endDate->format('n')],
            'year' => $endDate->format('Y'),
            'planned' => $this->urgencyGroup($patients, 'planned'),
            'urgent' => $this->urgencyGroup($patients, 'urgent'),
            'inDepartment' => $patients->where('period_flags.current_at_end', true)->count(),
            'plannedOperations' => $this->operationsGroup($patients, [6]),
            'urgentOperations' => $this->operationsGroup($patients, [4, 5]),
            'reanimation' => $this->flagGroup($patients, 'in_reanimation'),
            'observableCount' => $patients->where('in_observable', true)->count(),
            'deceased' => $this->flagGroup($patients, 'period_flags.deceased'),
        ];
    }

    private function urgencyGroup(Collection $patients, string $flag): array
    {
        $filtered = $patients
            ->where('period_flags.current_at_end', true)
            ->where("period_flags.{$flag}", true)
            ->values();

        return [
            'count' => $filtered->count(),
            'patients' => $filtered->map(fn (array $p) => $this->presentPatient($p))->all(),
        ];
    }

    private function operationsGroup(Collection $patients, array $urgentStatuses): array
    {
        $filtered = $patients->filter(function (array $p) use ($urgentStatuses) {
            return collect($p['operations'] ?? [])->whereIn('urgent_status', $urgentStatuses)->isNotEmpty();
        })->values();

        return [
            'count' => $filtered->count(),
            'patients' => $filtered->map(fn (array $p) => $this->presentPatient($p, withDiagnosis: false))->all(),
        ];
    }

    private function flagGroup(Collection $patients, string $flag): array
    {
        $filtered = $patients->where($flag, true)->values();

        return [
            'count' => $filtered->count(),
            'patients' => $filtered->map(fn (array $p) => $this->presentPatient($p))->all(),
        ];
    }

    private function presentPatient(array $patient, bool $withDiagnosis = true): array
    {
        $age = ! empty($patient['birth_date'])
            ? Carbon::parse($patient['birth_date'])->diffInYears(Carbon::parse($this->dateRange[1]))
            : null;

        return [
            'full_name' => $patient['full_name'],
            'age' => $age !== null ? "{$age} ".$this->pluralizeAge($age) : '',
            'diagnosis' => $withDiagnosis ? (data_get($patient, 'latest_migration.diagnosis_name') ?? '') : null,
        ];
    }

    private function pluralizeAge(int $age): string
    {
        $mod100 = $age % 100;
        $mod10 = $age % 10;

        if ($mod100 >= 11 && $mod100 <= 14) {
            return 'лет';
        }

        return match ($mod10) {
            1 => 'год',
            2, 3, 4 => 'года',
            default => 'лет',
        };
    }
}