peer-at-code-backend/src/be/jeffcheasey88/peeratcode/framework/HttpUtil.java

package be.jeffcheasey88.peeratcode.framework;

import java.security.MessageDigest;
import java.util.ArrayList;
import java.util.List;

import org.json.simple.parser.JSONParser;

public class HttpUtil{

	private HttpUtil(){}

	public static void responseHeaders(HttpWriter writer, int code, String... headers) throws Exception{
		writer.write("HTTP/1.1 "+code+codeMessage(code)+"\n");
		for(String header : headers) writer.write(header+"\n");
		writer.write("\n");
		writer.flush();
		StackTraceElement[] e = Thread.currentThread().getStackTrace();
		System.out.println(e[2]+" -> response "+code);
	}

	public static List<String> readMultiPartData(HttpReader reader) throws Exception{
		List<String> list = new ArrayList<>();
		
		String boundary = reader.getHeader("content-type");
		if(boundary == null) return list;
		boundary = boundary.split(";")[1].split("=")[1];
		
		reader.readLine();
		
		while(reader.ready()){
			String line;
			while (((line = reader.readLine()) != null) && (line.length() > 0));
			String buffer = "";
			while (((line = reader.readLine()) != null) && (!line.startsWith("--"+boundary))){
				buffer += line;
			}
			list.add(buffer);
		}

		return list;
	}
	
	/*
	 * 
------WebKitFormBoundaryNUjiLBAMuX2dhxU7
Content-Disposition: form-data; name="answer"

12
------WebKitFormBoundaryNUjiLBAMuX2dhxU7
Content-Disposition: form-data; name="filename"

webpack.js
------WebKitFormBoundaryNUjiLBAMuX2dhxU7
Content-Disposition: form-data; name="code_file"; filename="webpack.js"
Content-Type: text/javascript


------WebKitFormBoundaryNUjiLBAMuX2dhxU7--
	 * 
	 */

	public static void switchToWebSocket(HttpReader reader, HttpWriter writer) throws Exception{
		String key = reader.getHeader("Sec-WebSocket-Key");
		if (key == null) throw new IllegalArgumentException();

		writer.write("HTTP/1.1 101 Switching Protocols\n");
		writer.write("Connection: Upgrade\n");
		writer.write("Upgrade: websocket\n");
		writer.write("Sec-WebSocket-Accept: " + printBase64Binary(MessageDigest.getInstance("SHA-1")
					.digest((key + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11").getBytes("UTF-8"))) + "\n");
		writer.write("\n");
		writer.flush();
	}

	public static Object readJson(HttpReader reader) throws Exception{
		String line = "";
		while (reader.ready()){
			char[] c = new char[1];
			reader.read(c);
			line += c[0];
			if (c[0] == '}'){
				Object parse;
				try {
					parse = new JSONParser().parse(line);
					if (parse != null)
						return parse;
				}catch(Exception e){}
			}
		}
		return null;
	}

	private static String codeMessage(int paramInt){
		switch (paramInt){
		case 200:
			return " OK";
		case 100:
			return " Continue";
		case 201:
			return " Created";
		case 202:
			return " Accepted";
		case 203:
			return " Non-Authoritative Information";
		case 204:
			return " No Content";
		case 205:
			return " Reset Content";
		case 206:
			return " Partial Content";
		case 300:
			return " Multiple Choices";
		case 301:
			return " Moved Permanently";
		case 302:
			return " Temporary Redirect";
		case 303:
			return " See Other";
		case 304:
			return " Not Modified";
		case 305:
			return " Use Proxy";
		case 400:
			return " Bad Request";
		case 401:
			return " Unauthorized";
		case 402:
			return " Payment Required";
		case 403:
			return " Forbidden";
		case 404:
			return " Not Found";
		case 405:
			return " Method Not Allowed";
		case 406:
			return " Not Acceptable";
		case 407:
			return " Proxy Authentication Required";
		case 408:
			return " Request Time-Out";
		case 409:
			return " Conflict";
		case 410:
			return " Gone";
		case 411:
			return " Length Required";
		case 412:
			return " Precondition Failed";
		case 413:
			return " Request Entity Too Large";
		case 414:
			return " Request-URI Too Large";
		case 415:
			return " Unsupported Media Type";
		case 500:
			return " Internal Server Error";
		case 501:
			return " Not Implemented";
		case 502:
			return " Bad Gateway";
		case 503:
			return " Service Unavailable";
		case 504:
			return " Gateway Timeout";
		case 505:
			return " HTTP Version Not Supported";
		}
		return " ";
	}

	// From javax.xml.bind.DatatypeConverter
	private static String printBase64Binary(byte[] array){
		char[] arrayOfChar = new char[(array.length + 2) / 3 * 4];
		int i = _printBase64Binary(array, 0, array.length, arrayOfChar, 0);
		assert i == arrayOfChar.length;
		return new String(arrayOfChar);
	}

	private static int _printBase64Binary(byte[] paramArrayOfbyte, int paramInt1, int paramInt2,
			char[] paramArrayOfchar, int paramInt3){
		int i = paramInt2;
		int j;
		for (j = paramInt1; i >= 3; j += 3){
			paramArrayOfchar[paramInt3++] = encode(paramArrayOfbyte[j] >> 2);
			paramArrayOfchar[paramInt3++] = encode(
					(paramArrayOfbyte[j] & 0x3) << 4 | paramArrayOfbyte[j + 1] >> 4 & 0xF);
			paramArrayOfchar[paramInt3++] = encode(
					(paramArrayOfbyte[j + 1] & 0xF) << 2 | paramArrayOfbyte[j + 2] >> 6 & 0x3);
			paramArrayOfchar[paramInt3++] = encode(paramArrayOfbyte[j + 2] & 0x3F);
			i -= 3;
		}
		if (i == 1){
			paramArrayOfchar[paramInt3++] = encode(paramArrayOfbyte[j] >> 2);
			paramArrayOfchar[paramInt3++] = encode((paramArrayOfbyte[j] & 0x3) << 4);
			paramArrayOfchar[paramInt3++] = '=';
			paramArrayOfchar[paramInt3++] = '=';
		}
		if (i == 2){
			paramArrayOfchar[paramInt3++] = encode(paramArrayOfbyte[j] >> 2);
			paramArrayOfchar[paramInt3++] = encode(
					(paramArrayOfbyte[j] & 0x3) << 4 | paramArrayOfbyte[j + 1] >> 4 & 0xF);
			paramArrayOfchar[paramInt3++] = encode((paramArrayOfbyte[j + 1] & 0xF) << 2);
			paramArrayOfchar[paramInt3++] = '=';
		}
		return paramInt3;
	}

	private static char encode(int paramInt){
		return encodeMap[paramInt & 0x3F];
	}

	private static final char[] encodeMap = initEncodeMap();

	private static char[] initEncodeMap(){
		char[] arrayOfChar = new char[64];
		byte b;
		for (b = 0; b < 26; b++)
			arrayOfChar[b] = (char) (65 + b);
		for (b = 26; b < 52; b++)
			arrayOfChar[b] = (char) (97 + b - 26);
		for (b = 52; b < 62; b++)
			arrayOfChar[b] = (char) (48 + b - 52);
		arrayOfChar[62] = '+';
		arrayOfChar[63] = '/';
		return arrayOfChar;
	}
}