package test.sematest;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.util.LinkedList;

import rep.REP;
import rep.REPCommand;
import rep.REPCommandPacker;
import rep.channel.REPLogger;
import rep.channel.REPSelectionKey;
import rep.channel.REPSelector;
import rep.channel.REPSocketChannel;
import test.Text;


/**
 * @author kono
 *	Basic Temote Editor client implementation
 *     should support multi-session
 *     currently multi-session requires new channel, that is
 *     only one session for this editor.
 */
public class TestEditor extends Thread{
	private InetSocketAddress semaIP;
	private REPLogger ns;
	private int seq = 0;
	public Text text;
	public LinkedList<REPCommand> cmds;
	private int eid = 0;
	private int sid = 0;
	REPSocketChannel<REPCommand> channel;
	REPCommand nop = new REPCommand(REP.REPCMD_NOP, 0, 0, 0, 0, "");
	boolean running = true;
	long timeout = 1;
	private String name;
	private boolean inputLock=false;
	public boolean detached=false;
	public boolean master=false;
	REPCommand quit=null;
	private int syncCounter=0;
	private boolean hasInputLock=false;
	private int port;
	private REPSelector<REPCommand> selector;
	private boolean syncEnable=false;


	public TestEditor(String name, String _host,int _port, boolean master){
		super(name);
		LinkedList<REPCommand>cmdList = new LinkedList<REPCommand>();
		String[] txts = {
			"aaa", "bbb", // "ccc", "ddd", "eee",
		};	
		port = _port;
		semaIP = new InetSocketAddress(_host, _port);
		ns = REPLogger.singleton();
		this.name = name;
		cmds = cmdList;
		if (master) {
			this.master=true;
			text = new Text(txts);
			cmds.add(new REPCommand(REP.SMCMD_PUT,0,0,0,0,name+"-file"));
			//cmds.add(new REPCommand(REP.REPCMD_INSERT,0,0,0,0,"m0"));
			cmds.add(new REPCommand(REP.REPCMD_DELETE,0,0,0,0,"m0"));
			//cmds.add(new REPCommand(REP.SMCMD_QUIT,0,0,0,0,""));
		} else {
			text = new Text(new String[0]);
			cmds.add(new REPCommand(REP.SMCMD_JOIN,0,0,0,0,name));
			cmds.add(new REPCommand(REP.REPCMD_INSERT,0,0,0,0,"c0"));
			//cmds.add(new REPCommand(REP.REPCMD_DELETE,0,0,0,0,"c0"));
		}
	}
	
	public TestEditor(String name, String _host,int _port, boolean master,
			String[] txts,LinkedList<REPCommand> cmdList){
		super(name);
		port = _port;
		semaIP = new InetSocketAddress(_host, _port);
		ns = REPLogger.singleton();
		this.name = name;
		cmds = cmdList;
		if (master) {
			this.master=true;
			text = new Text(txts);
		} else {
			text = new Text(new String[0]);
		}
	}

	public void run(){
		/*
		 * Create Socket and connect to the session manager
		 */
		try {
			channel = REPSocketChannel.<REPCommand>create(new REPCommandPacker());
		} catch (IOException e) {	return;	}

		ns.writeLog("try to connect to SessionManager whose ip is "+semaIP+" "+name, 1);
		try {
			while (!channel.connect(semaIP)){
				ns.writeLog("SeMa not listen to socket yet, wait", 1);
			}
		} catch (IOException e) { return; }
		ns.writeLog("successes to connect "+name);
		/*
		 * Start editor main loop
		 *         public REPCommand(REP cmd,int sid,int eid, int seq, int lineno,  String string) 
		 */
		try {
			mainloop();
		} catch (IOException e) {
		}
	}

	/*
	 * Editor main loop with input lock
	 */
	private void mainloop() throws IOException {
		
		channel.configureBlocking(false);
		REPSelector<REPCommand> selector = REPSelector.create();
		channel.register(selector, SelectionKey.OP_READ);
		this.selector = selector;
		while(running) {
			if (inputLock) {
				// No user input during merge mode (optional)
				if (selector.select(0)>0) {
					handle(channel.read());
				}
				continue;
			} else if (selector.select(timeout)<=0) {
				if (syncCounter>0) {
					syncText(); // send the master editor buffer to clients. 
				}
				userInput();
			}
			// selector(timeout) returns 0, but it may contain readable channel..
			for(REPSelectionKey<REPCommand> key : selector.selectedKeys1()) {
				REPSocketChannel<REPCommand> ch = key.channel1();
				handle(ch.read());
			}
		}
	}

	private void syncText() {
		/*
		 * Send delete/insert one at a time to synchronize
		 * all clients. SYNC is requested by the session manager.
		 */
		if (syncCounter>text.size()) {
			syncCounter=0;
		} else {
			int i=syncCounter-1;
			REPCommand del = new REPCommand(REP.REPCMD_DELETE,sid,eid,0,i, text.get(i));
			REPCommand ins = new REPCommand(REP.REPCMD_INSERT,sid,eid,0,i, text.get(i));
			sendCommand(del);
			sendCommand(ins);
			syncCounter++;
		}
	}

	/*
	 * Simulate User Input
	 */
	private void userInput() {
		REPCommand cmd = cmds.poll();
		if (cmd!=null) {
			switch(cmd.cmd) {
			case REPCMD_INSERT:
				text.insert(cmd.lineno, cmd.string);
				sendCommand(cmd);
				break;
			case REPCMD_DELETE:
				String del = text.delete(cmd.lineno);
				cmd.setString(del);
				sendCommand(cmd);
				break;
			case SMCMD_QUIT:
				/*
				 * start termination phase 1 by the master editor.
				 * after this command do not send any user input.
				 * clients simply disconnect from the session manager.
				 */
				cmds.clear();
				quit = cmd;
				break;
			case SMCMD_JOIN:
			case SMCMD_PUT:
				sendCommand(cmd);
				/*
				 * To prevent confusion, stop user input until the ack
				 */
				inputLock = true; // wait until ACK
				break;
			default:
				assert(false);
			}
		} else {
			if(syncCounter==0) {
			// no more command to send, and we don't have syncCounter
				timeout = 0;
				if (quit!=null) {
					sendCommand(quit);
					quit=null;
				}
			}
		}
	}


	private void sendCommand(REPCommand cmd1) {
		REPCommand cmd = new REPCommand(cmd1);
		cmd.setSEQID(seq++);
		cmd.setEID(eid);
		cmd.setSID(sid);
		ns.writeLog(name +" send "+cmd);
		channel.write(cmd);
	}

	private void forwardCommand(REPCommand cmd1) {
		REPCommand cmd = new REPCommand(cmd1);
		ns.writeLog(name +" forward "+cmd);
		channel.write(cmd);
	}

	private void handle(REPCommand cmd) {
		if (cmd==null) return;
		ns.writeLog(name +": read "+cmd);
		switch(cmd.cmd) {
		case REPCMD_INSERT	:
			text.insert(cmd.lineno, cmd.string);
			forwardCommand(cmd);
			break;
		case REPCMD_DELETE	:
			String del=""; 
			if(cmd.lineno>text.size()) {
				del = text.delete(cmd.lineno);
			}
			cmd.setString(del);
			forwardCommand(cmd);
			break;
		 case REPCMD_NOP		:
		 case REPCMD_INSERT_ACK		:
		 case REPCMD_DELETE_ACK		:
			 forwardCommand(cmd);
			 break;		 
		 case REPCMD_CLOSE	:
		 case REPCMD_CLOSE_2	:
				assert(false);
			 break;

		 case SMCMD_JOIN_ACK	:
			 sid = cmd.sid;
			 eid = cmd.eid;
			 name += "(eid="+eid+",sid="+sid+")";
			 inputLock = false;
			 break;
		 case SMCMD_PUT_ACK	:
			 sid = cmd.sid;
			 eid = cmd.eid;
			 name += "(eid="+eid+",sid="+sid+")";
			 inputLock = false;
			 break;
		 case SMCMD_QUIT		:
			 if (cmd.eid!=eid)
				 forwardCommand(cmd);
			 else
				 sendCommand(new REPCommand(REP.SMCMD_QUIT_2, 
						 sid, eid, seq, 0, ""));
			 // stop input processing after this command
			 cmds.clear();
			 break;
		 case SMCMD_START_MERGE :
			 // lock user input during merge (optional)
			 inputLock = hasInputLock;
			 cmd.cmd = REP.SMCMD_START_MERGE_ACK;
			 sendCommand(cmd);
			 break;
		 case SMCMD_END_MERGE :
			 inputLock = false;
			 break;
		 case SMCMD_QUIT_2 :
			 if (cmd.eid!=eid) {
				 forwardCommand(cmd);
			 } else {
				 cmd.cmd = REP.SMCMD_QUIT_2_ACK;
				 sendCommand(cmd);
			 }
			 running = false;
			 break;
		 case SMCMD_SYNC:
			 // start contents sync with newly joined editor
			 cmd.cmd = REP.SMCMD_SYNC_ACK;
			 forwardCommand(cmd);
			 //if (cmd.eid==eid) {
			 if (master && syncEnable ) {
				 syncCounter = 1;
				 timeout = 1;
			 }
			 break;
		 default:
			 assert(false);
		 	 break;
		}
	}


	public int getPort() {
		return port;
	}

	public synchronized void setCommand(LinkedList<REPCommand> cmds) {
		this.cmds = cmds;
		timeout=1;
		if(selector!=null) selector.wakeup();
	}
}