<?php

namespace NoccyLabs\Spinner;


class Spinner
{
    private static $defaultStyle = Style\BrailleDotsStyle::class;

    private static $defaultFps = 10;

    private array $frames = [];

    private int $frame = 0;

    private float $lastAdvance = 0;

    private float $advanceIv = 0;

    public static function setDefaultStyle(string $class)
    {
        $inst = new $class;
        if (!($inst instanceof Style\StyleInterface)) {
            throw new \DomainException();
        }
        self::$defaultStyle = $class;
    }

    public function __construct(?string $style=null, ?int $fps=null)
    {
        $style = $style??self::$defaultStyle;
        $fps = $fps??self::$defaultFps;

        $this->advanceIv = 1.0 / $fps;

        $style = new $style();
        $this->frames = $style->getFrames();
    }

    public function __toString()
    {
        $now = microtime(true);
        if ($this->lastAdvance + $this->advanceIv < $now) {
            $this->frame = ($this->frame + 1) % count($this->frames);
            $this->lastAdvance = $now;
        }
        return $this->frames[$this->frame];
    }
}