PHP Bash colour re-factor...

TextColorHelper.php

<?php

namespace {
    use \lewiscowles\nix\terminal\bash\TextColorHelper;
    $bashTxt = new TextColorHelper();
    $bashTxt->setString( 'Normal Text' )
            ->output()
            ->setString( 'Less Normal Text', 'light_purple' )
            ->output()
            ->setString( 'Success', 'light_green' )
            ->output()
            ->setString( 'Warning!', 'light_gray', 'yellow' )
            ->output()
            ->setColor( 'red', TextColorHelper::BG )
            ->setString( 'Error :(' )
            ->output()
            ->setString( 'Info!', 'white', 'blue' )
            ->output()
            ->setString( 'More Weirdness!', 'light_cyan', 'magenta' )
            ->output();
}

namespace lewiscowles\nix\terminal\bash {

	class TextColorHelper {

		const FG = 'f';
		const BG = 'b';

		private static $_fg_colors = [
			'black' => '0;30',
			'dark_gray' => '1;30',
			'blue' => '0;34',
			'light_blue' => '1;34',
			'green' => '0;32',
			'light_green' => '1;32',
			'cyan' => '0;36',
			'light_cyan' => '1;36',
			'red' => '0;31',
			'light_red' => '1;31',
			'purple' => '0;35',
			'light_purple' => '1;35',
			'brown' => '0;33',
			'yellow' => '1;33',
			'light_gray' => '0;37',
			'white' => '1;37',
		];

		private static $_bg_colors = [
			'black' => '40',
			'red' => '41',
			'green' => '42',
			'yellow' => '43',
			'blue' => '44',
			'magenta' => '45',
			'cyan' => '46',
			'light_gray' => '47',
		];

		protected $fg = 'white';
		protected $bg = 'black';
		protected $str = '';

		public function __construct( $fgColor=null, $bgColor=null ) {
			$this->setColors( $fgColor, $bgColor );
		}

		protected function getC( $flag=self::FG ) {
			$out = '';
			switch( $flag ) {
				case self::FG:
					if( isset( self::$_fg_colors[ $this->fg ] ) ) {
						$out = self::$_fg_colors[ $this->fg ];
					} else {
						throw new Exception('Invalid Color String Exception');
					}
					break;
				case self::BG:
					if( isset( self::$_bg_colors[ $this->bg ] ) ) {
						$out = self::$_bg_colors[ $this->bg ];
					} else {
						throw new Exception('Invalid Color String Exception');
					}
					break;
			}
			return $out;
		}

		// Returns colored string
		public function setString( $string, $fg_color = null, $bg_color = null ) {
			$colored_string = ""; // start with a blank string
			$this->setColor( $fg_color, self::FG ); // override fg if set
			$this->setColor( $bg_color, self::BG ); // override bg if set
			$this->str = sprintf( "\033[%sm\033[%sm%s\033[0m", $this->getC( self::FG ), $this->getC( self::BG ), $string );
			
			/*
			$colored_string .= "\033[" . self::$_fg_colors[ $this->fg ] . "m";
			$colored_string .= "\033[" . self::$_bg_colors[ $this->bg ] . "m";
			$colored_string .=  $string . "\033[0m";
			*/

			return $this; // chain
		}

		public function output() {
    		echo $this."\n";
    		return $this;
		}

		public function __toString() {
			return $this->str;
		}

		public function setColors($fg_color = null, $bg_color = null) {
			$this->setColor( $fg_color, self::FG );
			$this->setColor( $bg_color, self::BG );
			return $this;
		}

		public function setColor( $color_str, $flag=self::FG ) {
			if( isset( $color_str ) ) {
				switch( $flag ) {
					case self::FG:
						if( isset( self::$_fg_colors[ strtolower( $color_str ) ] ) ) {
							$this->fg = strtolower( $color_str );
						} else {
							throw new \Exception('Invalid Color String Exception');
						}
						break;
					case self::BG:
						if( isset( self::$_bg_colors[ strtolower( $color_str ) ] ) ) {
							$this->bg = strtolower( $color_str );
						} else {
							throw new \Exception('Invalid Color String Exception');
						}
						break;
				}
			}
			return $this;
		}

		// Returns all foreground color names
		public static function getForegroundColors() {
			return array_keys( self::$_fg_colors );
		}

		// Returns all background color names
		public static function getBackgroundColors() {
			return array_keys( self::$_bg_colors );
		}
	}

}