<?php

namespace App\Models\NetworksTraining;

use App\Events\PerceptronTrainingEnded;
use App\Exceptions\TrainingCancelledException;
use App\Models\ActivationsFunctions;
use App\Services\DatasetReader\IDataSetReader;
use App\Services\IterationEventBuffer\IPerceptronIterationEventBuffer;
use Closure;

abstract class NetworkTraining
{
    protected int $epoch = 0;

    /**
     * @abstract
     */
    public ActivationsFunctions $activationFunction;

    public ?ActivationsFunctions $presentationLayerActivationFunction = null;

    public function __construct(
        protected IDataSetReader $datasetReader,
        protected int $maxEpochs,
        protected IPerceptronIterationEventBuffer $iterationEventBuffer,
        protected string $sessionId,
        protected string $trainingId,
        protected ?Closure $isCancelled = null,
    ) {}

    abstract public function start(): void;

    abstract protected function stopCondition(): bool;

    protected function checkPassedMaxIterations(?float $finalError)
    {
        if ($this->epoch >= $this->maxEpochs) {
            $message = 'Le nombre maximal d\'époques a été atteint';
            if ($finalError) {
                $message .= " avec une erreur finale de $finalError";
            }

            event(new PerceptronTrainingEnded($message, $this->sessionId, $this->trainingId));
        }
    }

    protected function broadcastTrainingEnded(string $reason): void
    {
        $this->iterationEventBuffer->flush();
        event(new PerceptronTrainingEnded($reason, $this->sessionId, $this->trainingId));
    }

    protected function addIterationToBuffer(float $error, array $synapticWeights)
    {
        if ($this->isCancelled !== null && ($this->isCancelled)()) {
            throw new TrainingCancelledException;
        }

        $this->iterationEventBuffer->addIteration($this->epoch, $this->datasetReader->getLastReadLineIndex(), $error, $synapticWeights);
    }

    public function cancel(): void
    {
        $this->broadcastTrainingEnded('Entraînement annulé');
    }

    public function getEpoch(): int
    {
        return $this->epoch;
    }

    abstract public function getSynapticWeights(): array;
}