<?php

namespace App\Model\Event;

use App\DB;
use App\Model\Event;
use App\Model\Unit;
use App\Model\Unit\Merchant;
use App\Model\Village;

class SendResources extends BaseEvent
{
  public int $wood = 0;
  public int $clay = 0;
  public int $iron = 0;
  public int $food = 0;

  public int $source;
  public int $destination;

  public bool $isCanceled = false;

  /**
   * @return void
   */
  public function __invoke(): void
  {
    if ($this->isCanceled) {
      // TODO: switch destination and source
      // TODO: add resources back to "destination"
      // TODO: add merchants back to "destination"
    }

    else {
      // TODO: account for storage capacity
      DB::query(
        'update villages set wood=wood+:wood, clay=clay+:clay, iron=iron+:iron, food=food+:food where id=:id',
        [
          'wood' => $this->wood,
          'clay' => $this->clay,
          'iron' => $this->iron,
          'food' => $this->food,
          'id' => $this->destination,
        ]
      );

      $source = Village::get($this->source);
      $destination = Village::get($this->destination);

      $event = new Event();
      $event->time = (new \DateTime())->add(
        \DateInterval::createFromDateString(
          Unit::getTravelTime(new Merchant(), Village::getDistance($source->x, $source->y, $destination->x, $destination->y))
            . ' seconds'
        )
      );
      $event->villageId = $this->source;

      $sendResourcesMerchants = new SendResourcesMerchants();
      $sendResourcesMerchants->dbInsert($this->id);


      // TODO: add resources to destination
      // (TODO: add foreign merchants to destination)?
      // TODO: create SendUnits event with merchants back to source
    }
  }

  public function dbInsert(): void
  {
    DB::query(
      'insert into events (time, village_id) VALUES (:time, :village_id)',
      ['time' => $this->event->time->format('c'), 'village_id' => $this->event->villageId]
    );

    DB::query(
      <<<SQL
      insert into events_send_resources (event_id, wood, clay, iron, food, source, destination, is_canceled)
      VALUES (:event_id, :wood, :clay, :iron, :food, :source, :destination, :is_canceled)
      SQL,
      [
        'event_id' => DB::$connection->lastInsertId(),
        'wood' => $this->wood,
        'clay' => $this->clay,
        'iron' => $this->iron,
        'food' => $this->food,
        'source' => $this->source, 'destination' => $this->destination,
        'is_canceled' => $this->isCanceled ?: 0, // @see https://www.php.net/manual/de/pdostatement.execute.php#126013
      ]
    );
    $sendResourcesEventId = DB::$connection->lastInsertId();

    $resourceCapabilities = Merchant::getResourceCapabilities($this->event->villageId);
    $resourcesTotal = $this->wood + $this->clay + $this->iron + $this->food;
    $necessaryMerchants = ceil($resourcesTotal / $resourceCapabilities);

    $merchantsAccountedFor = 0;
    while ($merchantsAccountedFor < $necessaryMerchants) {
      $merchants = DB::fetch(
        Merchant::class,
        'select * from village_units where type=:type and residence_village_id=:villageId and is_traveling=false',
        ['type' => 'Merchant', 'villageId' => $this->source]
      );
      foreach ($merchants as $merchant) {
        /**@type Merchant $merchant*/

        $currentlyNecessaryMerchants = $necessaryMerchants - $merchantsAccountedFor;
        $currentlyUseableMerchants = $currentlyNecessaryMerchants - $merchant->amount < 0 ? $currentlyNecessaryMerchants : $merchant->amount;
        $merchantsAccountedFor += $currentlyUseableMerchants;

        DB::query(
          <<<SQL
          insert into village_units (amount, type, is_traveling, home_village_id, residence_village_id)
          VALUES (:amount, :type, true, :home, :residence)
            on conflict (type, home_village_id, residence_village_id, is_traveling)
            do update set is_traveling=true
          SQL,
          [
            'amount' => $currentlyUseableMerchants,
            'type' => 'Merchant',
            'home' => $merchant->homeVillageId,
            'residence' => $merchant->residenceVillageId,
          ]
        );
        DB::query('update village_units set amount=amount-:amount where id=:unitId', ['amount' => $necessaryMerchants, 'unitId' => $merchant->id]);

        DB::query(
          <<<SQL
          insert into events_send_resources_merchants (event_id, unit_id, amount)
          VALUES (:event_id, :unit_id, :amount)
          SQL,
          [
            'event_id' => $sendResourcesEventId,
            'unit_id' => $merchant->id,
            'amount' => $necessaryMerchants,
          ]
        );
      }
    }

    // TODO: remove resources from source
  }

  public function dbDelete(): void
  {
    DB::query('delete from events where id=:id', ['id' => $this->eventId]);
    DB::query('delete from events_send_resources where id=:id', ['id' => $this->id]);
    #DB::query('delete from events_send_resources_merchants where event_id=:id', ['id' => $this->id]);
  }
}