<?php
namespace YTKNS;

use InvalidArgumentException;

final class GradientPoint {
    private int $offset = 0;
    private $colour = null;

    public function __construct(int $offset = 0, \Colour $colour = null) {
        $this->setOffset($offset);
        if($colour !== null)
            $this->setColour($colour);
    }

    public function getArray(): array {
        return [
            'o' => $this->getOffset(),
            'c' => $this->getColour()->getRaw(),
        ];
    }

    public static function fromArray($array): self {
        $point = new static;

        if(!empty($array)) {
            if(is_string($array))
                $array = json_decode($array);
            if(is_object($array))
                $array = (array)$array;
            if(is_array($array)) {
                if(isset($array['o']) && is_int($array['o']))
                    $point->setOffset($array['o']);
                if(isset($array['c']))
                    $point->setColour(Colour::create($array['c']));
            }
        }

        return $point;
    }

    public function getOffset(): int {
        return $this->offset;
    }
    public function setOffset(int $offset): self {
        if($offset < 0 || $offset > 100)
            throw new InvalidArgumentException('offset must be between 0 and 100');
        $this->offset = $offset;
        return $this;
    }

    public function getColour(): Colour {
        if($this->colour === null)
            $this->colour = new Colour;
        return $this->colour;
    }
    public function setColour(Colour $colour): self {
        $this->colour = $colour;
        return $this;
    }

    public function getCSS(): string {
        return sprintf('#%s %d%%', $this->getColour()->getHex(), $this->getOffset());
    }
}