<?php

namespace App\Services;

use App\Models\InhabitantClassification;
use App\Models\Unit;
use App\Models\UnitInhabitantClassification;
use Illuminate\Database\Eloquent\Collection;

class InhabitantClassificationService
{
    public function getAll(): Collection
    {
        return InhabitantClassification::orderBy('id')->get();
    }

    public function getSelectList(): Collection
    {
        return InhabitantClassification::orderBy('id')
            ->get(['id', 'description', 'start', 'end', 'tbr_percentage']);
    }

    public function findById(int $id): ?InhabitantClassification
    {
        return InhabitantClassification::find($id);
    }

    public function create(array $data): InhabitantClassification
    {
        $model = InhabitantClassification::create($data);
        $this->propagateToAllUnits($model);
        return $model;
    }

    public function update(int $id, array $data): ?InhabitantClassification
    {
        $model = $this->findById($id);

        if (!$model) {
            return null;
        }

        $oldStart          = $model->start;
        $oldEnd            = $model->end;
        $oldTbrPercentage  = $model->tbr_percentage;
        $oldDescription    = $model->description;

        $model->update($data);
        $updated = $model->fresh();

        $this->propagateUpdateToUnits($updated, [
            'description'    => $oldDescription,
            'start'          => $oldStart,
            'end'            => $oldEnd,
            'tbr_percentage' => $oldTbrPercentage,
        ]);

        return $updated;
    }

    public function delete(int $id): bool
    {
        $model = $this->findById($id);

        if (!$model) {
            return false;
        }

        return $model->delete();
    }

    //

    private function propagateToAllUnits(InhabitantClassification $parent): void
    {
        $existingUnitIds = UnitInhabitantClassification::where('start', $parent->start)
            ->where('end', $parent->end)
            ->pluck('unit_id');

        Unit::whereNotIn('id', $existingUnitIds)
            ->each(function (Unit $unit) use ($parent) {
                UnitInhabitantClassification::create([
                    'unit_id'        => $unit->id,
                    'description'    => $parent->description,
                    'start'          => $parent->start,
                    'end'            => $parent->end,
                    'tbr_percentage' => $parent->tbr_percentage,
                ]);
            });
    }

    private function propagateUpdateToUnits(InhabitantClassification $parent, array $old): void
    {
        // propaga a atualizacao para as classificacoes de unidades que tenham os mesmos valores antigos
        UnitInhabitantClassification::where('start', $old['start'])
            ->where('end', $old['end'])
            ->where('tbr_percentage', $old['tbr_percentage'])
            ->where('description', $old['description'])
            ->update([
                'description'    => $parent->description,
                'start'          => $parent->start,
                'end'            => $parent->end,
                'tbr_percentage' => $parent->tbr_percentage,
            ]);

        // garante que todas as unidades tenham a classificacao, criando para as que ainda nao tem
        $coveredUnitIds = UnitInhabitantClassification::where(function ($q) use ($parent, $old) {
                $q->where(fn($q) => $q->where('start', $parent->start)->where('end', $parent->end))
                  ->orWhere(fn($q) => $q->where('start', $old['start'])->where('end', $old['end']));
            })
            ->pluck('unit_id')
            ->unique();

        Unit::whereNotIn('id', $coveredUnitIds)
            ->each(function (Unit $unit) use ($parent) {
                UnitInhabitantClassification::create([
                    'unit_id'        => $unit->id,
                    'description'    => $parent->description,
                    'start'          => $parent->start,
                    'end'            => $parent->end,
                    'tbr_percentage' => $parent->tbr_percentage,
                ]);
            });
    }
}