package com.jcoglan.websocket;

import java.lang.Long; import java.io.IOException;

import org.jruby.Ruby; import org.jruby.RubyArray; import org.jruby.RubyClass; import org.jruby.RubyFixnum; import org.jruby.RubyModule; import org.jruby.RubyObject; import org.jruby.anno.JRubyMethod; import org.jruby.runtime.ObjectAllocator; import org.jruby.runtime.ThreadContext; import org.jruby.runtime.builtin.IRubyObject; import org.jruby.runtime.load.BasicLibraryService;

public class WebsocketMaskService implements BasicLibraryService {

private Ruby runtime;

public boolean basicLoad(Ruby runtime) throws IOException {
  this.runtime = runtime;
  RubyModule websocket = runtime.defineModule("WebSocket");

  RubyClass webSocketMask = websocket.defineClassUnder("Mask", runtime.getObject(), new ObjectAllocator() {
    public IRubyObject allocate(Ruby runtime, RubyClass rubyClass) {
      return new WebsocketMask(runtime, rubyClass);
    }
  });

  webSocketMask.defineAnnotatedMethods(WebsocketMask.class);
  return true;
}

public class WebsocketMask extends RubyObject {
  public WebsocketMask(final Ruby runtime, RubyClass rubyClass) {
    super(runtime, rubyClass);
  }

  @JRubyMethod
  public IRubyObject mask(ThreadContext context, IRubyObject payload, IRubyObject mask) {
    if (mask.isNil() || ((RubyArray)mask).getLength() == 0) {
      return payload;
    }

    int n = ((RubyArray)payload).getLength(), i;
    long p, m;
    RubyArray unmasked = RubyArray.newArray(runtime, n);

    long[] maskArray = {
      (Long)((RubyArray)mask).get(0),
      (Long)((RubyArray)mask).get(1),
      (Long)((RubyArray)mask).get(2),
      (Long)((RubyArray)mask).get(3)
    };

    for (i = 0; i < n; i++) {
      p = (Long)((RubyArray)payload).get(i);
      m = maskArray[i % 4];
      unmasked.set(i, p ^ m);
    }
    return unmasked;
  }
}

}