shrink0r/workflux

<?php

namespace Workflux\State;

use Ds\Map;
use Ds\Vector;
use Shrink0r\SuffixTree\Builder\SuffixTreeBuilder;
use Workflux\StateMachineInterface;
use Workflux\State\StateInterface;

final class ExecutionTracker
{
    /**
     * @var Vector $breadcrumbs
     */
    private $breadcrumbs;

    /**
     * @var Map $execution_counts
     */
    private $execution_counts;

    /**
     * @var StateMachineInterface $state_machine
     */
    private $state_machine;

    /**
     * @param StateMachineInterface $state_machine
     */
    public function __construct(StateMachineInterface $state_machine)
    {
        $this->state_machine = $state_machine;
        $this->breadcrumbs = new Vector;
        $this->execution_counts = new Map;
        foreach ($state_machine->getStates() as $state) {
            $this->execution_counts[$state->getName()] = 0;
        }
    }

    /**
     * @param StateInterface $state
     *
     * @return int
     */
    public function track(StateInterface $state): int
    {
        $this->breadcrumbs->push($state->getName());
        $this->execution_counts[$state->getName()]++;
        return $this->execution_counts[$state->getName()];
    }

    /**
     * @param StateInterface $state
     *
     * @return int
     */
    public function getExecutionCount(StateInterface $state): int
    {
        return $this->execution_counts[$state->getName()];
    }

    /**
     * @return Vector
     */
    public function getBreadcrumbs(): Vector
    {
        return clone $this->breadcrumbs;
    }

    /**
     * @return Vector
     */
    public function detectExecutionLoop(): Vector
    {
        $execution_path = implode(' ', $this->breadcrumbs->toArray());
        $loop_path = $execution_path;
        $tree_builder = new SuffixTreeBuilder;
        while (str_word_count($loop_path) > count($this->state_machine->getStates())) {
            $suffix_tree = $tree_builder->build($loop_path.'$');
            $loop_path = trim($suffix_tree->findLongestRepetition());
        }
        return new Vector(explode(' ', $loop_path));
    }
}