Added named colors (#87)

* Added named colors

* Added named colors

README.md

@@ -10,9 +10,17 @@
 [![Total Downloads](https://img.shields.io/packagist/dt/spatie/color.svg?style=flat-square)](https://packagist.org/packages/spatie/color)
 ![Tests](https://github.com/spatie/color/workflows/Tests/badge.svg)
 
-A little library to handle color conversions and comparisons. Currently supports rgb, rgba, hex, hsl, hsla, CIELab, and xyz color formats as well as CIE76, CIE94, and CIEDE2000 color comparison algorithms.
+A little library to handle color conversions and comparisons. Currently, supports CSS names, rgb, rgba, hex, hsl, hsla, CIELab, and xyz color formats as well as CIE76, CIE94, and CIEDE2000 color comparison algorithms.
 
 ```php
+$named = Named::fromString('peru'); // case-insensitive
+
+echo $named->red(); // 205
+echo $named->green(); // 133
+echo $named->blue(); // 63
+
+echo $named->toHex(); // #cd853f
+
 $rgb = Rgb::fromString('rgb(55,155,255)');
 
 echo $rgb->red(); // 55
@@ -102,6 +110,7 @@ There are seven classes which implement the `Color` interface:
 Parses a color string and returns a `Color` implementation, depending on the format of the input string.
 
 ```php
+Named::fromString('blue');
 Hex::fromString('#000000');
 Rgba::fromString('rgba(255, 255, 255, 1)');
 Hsla::fromString('hsla(360, 100%, 100%, 1)');
@@ -250,6 +259,7 @@ With the `Factory` class, you can create a color instance from any string (it do
 
 ```php
 Factory::fromString('rgb(0, 0, 255)'); // `Rgb` instance
+Factory::fromString('blue'); // `Named` instance
 Factory::fromString('#0000ff'); // `Hex` instance
 Factory::fromString('hsl(240, 100%, 50%)'); // `Hsl` instance
 Factory::fromString('Hello world!'); // `InvalidColorValue` exception

src/Exceptions/InvalidColorValue.php

@@ -97,4 +97,9 @@ public static function xyzValueNotInRange(float $value, string $name, float $min
     {
         return new static("Xyz value `{$name}` must be a number between $min and $max");
     }
+
+    public static function malformedNamedColorString(string $string): self
+    {
+        return new static("Color string `{$string}` doesn't match any of the available colors.");
+    }
 }

src/Factory.php

@@ -24,6 +24,7 @@ public static function fromString(string $string): Color
     protected static function getColorClasses(): array
     {
         return [
+            Named::class,
             CIELab::class,
             Cmyk::class,
             Hex::class,

src/Hex.php

@@ -12,10 +12,10 @@ class Hex implements Color
 
     public function __construct(string $red, string $green, string $blue, string $alpha = 'ff')
     {
-        Validate::hexChannelValue($red, 'red');
-        Validate::hexChannelValue($green, 'green');
-        Validate::hexChannelValue($blue, 'blue');
-        Validate::hexChannelValue($alpha, 'alpha');
+        Validate::hexChannelValue($red);
+        Validate::hexChannelValue($green);
+        Validate::hexChannelValue($blue);
+        Validate::hexChannelValue($alpha);
 
         $this->red = strtolower($red);
         $this->green = strtolower($green);

src/Named.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace Spatie\Color;
+
+use Spatie\Color\Exceptions\InvalidColorValue;
+
+class Named extends Rgb
+{
+    use Names;
+
+    protected $name;
+
+    public function __construct(string $name)
+    {
+
+        $this->name = strtolower($name);
+
+        if (! array_key_exists($this->name, $this->names)) {
+            throw InvalidColorValue::malformedNamedColorString($name);
+        }
+
+        $color = $this->names[$this->name];
+
+        parent::__construct($color[0], $color[1], $color[2]);
+    }
+
+    public static function fromString(string $string)
+    {
+        Validate::namedColorString($string);
+
+        return new static($string);
+    }
+
+    public function __toString(): string
+    {
+        return $this->name;
+    }
+}