package de.blinkt.openvpn;

import java.io.FileDescriptor;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.DatagramSocket;
import java.util.LinkedList;
import java.util.List;
import java.util.Vector;

import android.net.LocalSocket;
import android.os.ParcelFileDescriptor;
import android.util.Log;

public class OpenVpnManagementThread implements Runnable {

	private static final String TAG = "openvpn";
	private LocalSocket mSocket;
	private VpnProfile mProfile;
	private OpenVpnService mOpenVPNService;
	private LinkedList<FileDescriptor> mFDList=new LinkedList<FileDescriptor>(); 

	private static Vector<OpenVpnManagementThread> active=new Vector<OpenVpnManagementThread>();

	public OpenVpnManagementThread(VpnProfile profile, LocalSocket mgmtsocket, OpenVpnService openVpnService) {
		mProfile = profile;
		mSocket = mgmtsocket;
		mOpenVPNService = openVpnService;
	}


	private String managmentEscape(String unescape) {
		String escapedString = unescape.replace("\\", "\\\\");
		escapedString = escapedString.replace("\"","\\\"");
		escapedString = escapedString.replace("\n","\\n");
		return '"' + escapedString + '"';
	}


	public void managmentCommand(String cmd) {
		try {
			mSocket.getOutputStream().write(cmd.getBytes());
			mSocket.getOutputStream().flush();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}


	@Override
	public void run() {
		Log.i(TAG, "Managment Socket Thread started");
		byte [] buffer  =new byte[2048];
		//	mSocket.setSoTimeout(5); // Setting a timeout cannot be that bad
		InputStream instream = null;
		try {
			instream = mSocket.getInputStream();
		} catch (IOException e) {
			e.printStackTrace();
		}
		String pendingInput="";
		active.add(this);

		try {

			while(true) {
				int numbytesread = instream.read(buffer);
				if(numbytesread==-1)
					return;

				FileDescriptor[] fds = null;
				try {
					fds = mSocket.getAncillaryFileDescriptors();
				} catch (IOException e) {
					e.printStackTrace();
				}
				if(fds!=null){

					for (FileDescriptor fd : fds) {

						mFDList.add(fd);
					}
				}

				String input = new String(buffer,0,numbytesread,"UTF-8");

				pendingInput += input;

				pendingInput=processInput(pendingInput);



			}
		} catch (IOException e) {
			e.printStackTrace();
		}
		active.remove(this);
	}

	//! Hack O Rama 2000!
	private void protectFileDescriptor(FileDescriptor fd) {
		try {
			Method getInt = FileDescriptor.class.getDeclaredMethod("getInt$");
			int fdint = (Integer) getInt.invoke(fd);
	
			Log.d("Openvpn", "Got FD from socket: " + fd + " " + fdint);
			ParcelFileDescriptor pfd = ParcelFileDescriptor.fromFd(fdint);
			mOpenVPNService.protect(fdint);
			pfd.close();
			return;
		} catch (NoSuchMethodException e) {
			e.printStackTrace();
		} catch (IllegalArgumentException e) {
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		} catch (InvocationTargetException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		Log.d("Openvpn", "Failed to retrieve fd from socket: " + fd);
	}

	private String processInput(String pendingInput) {


		while(pendingInput.contains("\n")) {
			String[] tokens = pendingInput.split("\\r?\\n", 2);
			processCommand(tokens[0]);
			if(tokens.length == 1)
				// No second part, newline was at the end
				pendingInput="";
			else
				pendingInput=tokens[1];
		}
		return pendingInput;
	}


	private void processCommand(String command) {
		if (command.startsWith(">") && command.contains(":")) {
			String[] parts = command.split(":",2);
			String cmd = parts[0].substring(1);
			String argument = parts[1];


			if(cmd.equals("INFO"))
				logStatusMessage(command);
			else if (cmd.equals("PASSWORD")) {
				processPWCommand(argument);
			} else if (cmd.equals("HOLD")) {
				managmentCommand("hold release\n");
			} else if (cmd.equals("NEED-OK")) {
				processPWCommand(argument);
			} else {
				Log.i(TAG, "Got unrecognized command" + command);
			}
		} else {
			Log.i(TAG, "Got unrecognized line from managment" + command);
		}
	}

	private void processPWCommand(String argument) {
		//argument has the form 	Need 'Private Key' password
		int p1 =argument.indexOf('\'');
		int p2 = argument.indexOf('\'',p1+1);
		//String needed = argument.replace("Need '", "").replace("' password", "");
		String needed = argument.substring(p1+1, p2);

		String pw=null;
		String response="password";

		if(needed.equals("Private Key")) {
			pw = mProfile.getPasswordPrivateKey();
		} else if (needed.equals("Auth")) {
			String usercmd = String.format("username '%s' %s\n", 
					needed, managmentEscape(mProfile.mUsername));
			managmentCommand(usercmd);
			pw = mProfile.getPasswordAuth();
		} else if (needed.equals("PROTECTFD")) {
			FileDescriptor fdtoprotect = mFDList.pollFirst();
			protectFileDescriptor(fdtoprotect);
			pw = "ok";
			response="needok";
		}
		if(pw!=null) {
			String cmd = String.format("%s '%s' %s\n",response, needed, managmentEscape(pw));
			managmentCommand(cmd);
		}

	}




	private void logStatusMessage(String command) {
		OpenVPN.logMessage(0,"MGMT:", command);
	}


	public static boolean stopOpenVPN() {
		boolean sendCMD=false;
		for (OpenVpnManagementThread mt: active){
			mt.managmentCommand("signal SIGINT\n");
			sendCMD=true;
		}
		return sendCMD;		
	}

}