PHP script for colorful Xonotic Chat

xonchat.php

<?php
/**
 * \file
 * \brief Simple web script to get colorful text in Xonotic
 * \par Basic Usage
 * \code menu_cmd qc_curl --exec http://localhost/this_script.php cmd echo c1 000 c2 fff text "Hello world" \endcode
 * \par Example with aliases
\code
set mb_net_chat_server "http://localhost/xonchat/index.php"
alias mb_net_chat "menu_cmd qc_curl --exec $mb_net_chat_server cmd \"$1\" c1 $2 c2 $3 text \"$mb_net_str\""
alias mb_net_say "set mb_net_str \"${3- q}\"; mb_net_chat say $1 $2"
alias mb_net_echo "set mb_net_str \"${3- q}\"; mb_net_chat echo $1 $2"

alias mb_net_rainbow_chat "menu_cmd qc_curl --exec $mb_net_chat_server cmd \"$1\" text \"$mb_net_str\""
alias mb_net_rainbow_say "set mb_net_str \"${* q}\"; mb_net_rainbow_chat say"
alias mb_net_rainbow_echo "set mb_net_str \"${* q}\"; mb_net_rainbow_chat echo"
\endcode
 */


/**
 * \brief Simple, 12 bit rgb color
 */
class Color
{
	public $r, $g, $b;
	
	function __construct ($r=0, $g=0, $b=0)
	{
		$this->r = $r;
		$this->g = $g;
		$this->b = $b;
	}
	
	/**
	 * \brief Get the 12bit integer
	 */
	function bitmask()
	{
		return ($this->r<<8)|($this->g<<4)|$this->b;
	}
	
	/**
	 * \brief Encode to darkplaces
	 */
	function encode()
	{
		/*switch ( $this->bitmask() )
		{
			case 0x000: return "^0";
			case 0xf00: return "^1";
			case 0x0f0: return "^2";
			case 0xff0: return "^3";
			case 0x00f: return "^4";
			case 0xf0f: return "^6";
			case 0x0ff: return "^5";
			case 0xfff: return "^7";
		}*/
			
		return "^x".dechex($this->r).dechex($this->g).dechex($this->b);
	}
	
	/**
	 * \brief Decode darkplaces color
	 */
	static function decode($dpcolor)
	{
		$dpcolor = ltrim($dpcolor,"^x");
		
		if ( strlen($dpcolor) == 3 )
			return new Color(hexdec($dpcolor[0]),hexdec($dpcolor[1]),hexdec($dpcolor[2]));
		else if ( strlen($dpcolor) == 1 )
			switch ( $dpcolor[0])
			{
				case 0: return new Color(0,0,0);
				case 1: return new Color(0xf,0,0);
				case 2: return new Color(0,0xf,0);
				case 3: return new Color(0xf,0xf,0);
				case 4: return new Color(0,0,0xf);
				case 5: return new Color(0,0xf,0xf);
				case 6: return new Color(0xf,0,0xf);
				case 7: return new Color(0xf,0xf,0xf);
				case 8:
				case 9: return new Color(0x8,0x8,0x8);
			}
		return new Color();
	}
	
	/**
	 * \brief Blend two colors together
	 * \param $c1 First color
	 * \param $c2 Second color
	 * \param $factor Blend factor 0 => \c $c1, 1 => \c $c2
	 */
	static function blend(Color $c1, Color $c2, $factor)
	{
		return new Color(round($c1->r*(1-$factor) + $c2->r*$factor),
						 round($c1->g*(1-$factor) + $c2->g*$factor),
						 round($c1->b*(1-$factor) + $c2->b*$factor));
	}
	
	/**
	 * \brief Get a color from HSV components in [0,1]
	 */
	static function from_hsv($h,$s,$v)
	{
		
		$h *= 6;
		$c = $v*$s;
		$m = $v-$c;
		
		$h1 = floor($h);
		$f = $h - $h1;
		
		$n = $v - $c * $f;
		$k = $v - $c * (1 - $f);
		
		$v = round($v*0xf);
		$m = round($m*0xf);
		$n = round($n*0xf);
		$k = round($k*0xf);
		
		switch ($h1) 
		{
			case 0: return new Color($v,$k,$m);
			case 1: return new Color($n,$v,$m);
			case 2: return new Color($m,$v,$k);
			case 3: return new Color($m,$n,$v);
			case 4: return new Color($k,$m,$v);
			case 6:
			case 5: return new Color($v,$m,$n);
		}
		return new Color();
	}
}

class Char
{
	public $char, $color;
	
	function __construct($char, $color=null)
	{
		$this->char = $char;
		$this->color = $color;
	}
}

header("Content-Type: text/plain");

$color1 = Color::decode( isset($_REQUEST["c1"]) ? $_REQUEST["c1"] : "0" );
$color2 = Color::decode( isset($_REQUEST["c2"]) ? $_REQUEST["c2"] : "7" );
$rainbow = !isset($_REQUEST["c1"]) && !isset($_REQUEST["c2"]);
$cmd = isset($_REQUEST["cmd"]) ? $_REQUEST["cmd"] : "echo";
$text = isset($_REQUEST["text"]) ? $_REQUEST["text"] : "";


echo "$cmd ";

$text_arr = array();
$multichar = array();
$color = null;
for ( $i = 0; $i < strlen($text); $i++ )
{
	$c = $text[$i];
	$o = ord($c);
	
	if ( $o < 128 ) 
	{
		if ( $c == "^" && $i+1 < strlen($text))
		{
			if ( $text[$i+1] == "^" )
			{
				$i++; // skip second ^
				$text_arr []= new Char("^^",$color); // escaped ^^
				$color = null;
			}
			else if ( ctype_digit($text[$i+1]) )
			{
				$i++; // skip number
				$color = Color::decode($text[$i+1]); // ^n color
			}
			else if ( $text[$i+1] == 'x' && $i+4 < strlen($text) )
			{
				$color = Color::decode(substr($text,$i,5)); // ^xHHH color
				$i+=4; // skip color code
			}
		}
		else
		{
			$text_arr []= new Char($c,$color);
			$color = null;
		}
	}
	else // multi-byte UTF-8
	{
	
		if ( count($multichar) == 0 )
		{
			$s = "";
			$length = ( $o < 224 ) ? 2 : 3;
		}
		
		$multichar[] = $o;
		$s .= $c;
		
		if ( count( $multichar ) == $length ) 
		{
			$unicode = ( $length == 3 ) ?
				( ( $multichar[0] % 16 ) << 12 ) + ( ( $multichar[1] % 64 ) << 6 ) + ( $multichar[2] % 64 ):
				( ( $multichar[0] % 32 ) << 6 ) + ( $multichar[1] % 64 );
			$text_arr []= new Char($s,$color);
			$color = null;
			
			$multichar = array();
		}
	}
}

for ( $i = 0; $i < count($text_arr); $i++ )
{
	if ( $rainbow )
		$color = Color::from_hsv($i/count($text_arr),0.75,1);
	else
		$color = Color::blend($color1,$color2, $i == 0 ? 0 : $i/(count($text_arr)-1) );
	
	echo $text_arr[$i]->color ? $text_arr[$i]->color->encode() : $color->encode();
	echo $text_arr[$i]->char;
}