GoogleCurrencyCalculator.ragel

// Generated using:
// ragel -J -o src/com/appspot/btcticker/fsm/GoogleCurrencyCalculator.java GoogleCurrencyCalculator.ragel
//
package com.appspot.btcticker.fsm;

public class GoogleCurrencyCalculator {
	
	public static final String EURO_URL  = "http://www.google.com/ig/calculator?hl=en&q=1USD=?EUR";
	public static final String POUND_URL = "http://www.google.com/ig/calculator?hl=en&q=1USD=?GBP";
	public static final String DKK_URL   = "http://www.google.com/ig/calculator?hl=en&q=1USD=?DKK";

%%{
	machine currency_converter;
	write data;
	
    action clear { i = 0; f = 0.0; scale = 1.0; }
    action ipart { i = i * 10 + (int)data[p] - zero; }
    action fpart { scale = scale * 0.1; f = f + scale * ((int)data[p] - zero); }
    
    number = digit+ >clear $ipart ('.' digit+ $fpart)?
           ;
    
    lhs    = "lhs:" space* '"' (any - '"')* '"' ','
           ;
    rhs    = "rhs:" space* '"' number space (any - '"')* '"' ','
           ;
    error  = "error:" space* '"' '"' ','
           ;
    icc    =  "icc:" space* "true"
           ;
    
    main   := "{" lhs rhs error icc "}"
           ;
	
}%%

	public double extract(String response) {
	   char[] data = response.toCharArray();
        
        // Used by Ragel
        int cs;
        int p = 0;
        int pe = data.length;
        
        // Used to store extracted data
        final int zero = (int) '0';
        int i = 0;
        double f = 0.0;
        double scale = 1.0;
        
        %% write init;
        %% write exec;
        
        if (cs < currency_converter_first_final) {
        	return -1.0;
        }
        else {
        	return i + f;
        }
	}
}