/*
 * A RunThread is the thread that is responsible for running
 * the program in the background, in the GUI.  There is only one RunThread
 * and it should exist for the entire time the yoob GUI is running.
 * The source code in this file has been placed into the public domain.
 */
package tc.catseye.yoob;

import tc.catseye.yoob.State;

import java.lang.Thread;
import java.lang.InterruptedException;

import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.TimeUnit;

import java.awt.Cursor;


abstract class RunThreadMessage {
}

class HaltMessage extends RunThreadMessage {
}

class ProceedMessage extends RunThreadMessage {
}

class LoadMessage extends RunThreadMessage {
    public String name;
    public LoadMessage(String name) {
        this.name = name;
    }
}

// probably not really necessary, but it's what we have now
class SetTurboMessage extends RunThreadMessage {
    public boolean turbo;
    public SetTurboMessage(boolean turbo) {
        this.turbo = turbo;
    }
}

public class RunThread extends Thread {
    private SynchronousQueue<RunThreadMessage> mailbox;
    private ContentPane cp;
    private EsolangLoader loader;
    private int cyclesPerSecond;
    private boolean proceed, turbo;

    public RunThread(ContentPane cp, int cyclesPerSecond, EsolangLoader loader) {
        this.cp = cp;
        this.loader = loader;
        this.turbo = false;
        setRunSpeed(cyclesPerSecond);
        mailbox = new SynchronousQueue<RunThreadMessage>();
    }

    public void load(String name) {
        try {
            mailbox.put(new LoadMessage(name));
        } catch (InterruptedException e) {
            System.out.println("interrupted!");
        }
    }

    public void setTurbo(boolean turbo) {
        try {
            mailbox.put(new SetTurboMessage(turbo));
        } catch (InterruptedException e) {
            System.out.println("interrupted!");
        }
    }

    public void proceed() {
        try {
            mailbox.put(new ProceedMessage());
        } catch (InterruptedException e) {
            System.out.println("interrupted!");
        }
    }

    public void halt() {
        try {
            mailbox.put(new HaltMessage());
        } catch (InterruptedException e) {
            System.out.println("interrupted!");
        }
    }

    public void setRunSpeed(int cyclesPerSecond) {
        this.cyclesPerSecond = cyclesPerSecond;
    }

    public void run() {
        RunThreadMessage message;
        long delay;
        for (;;) {
            if (proceed) {
                if (turbo) {
                    int counter = 512;
                    while (proceed && counter > 0) {
                        proceed = cp.step();
                        counter--;
                    }
                    delay = 0;
                } else if (cyclesPerSecond > 0) {
                    delay = (long)(1000 / cyclesPerSecond);
                    proceed = cp.step();
                } else {
                    delay = 100; // and do nothing on this tick
                }
                try {
                    message = mailbox.poll(delay, TimeUnit.MILLISECONDS);
                } catch (InterruptedException e) {
                    message = null;
                }
            } else {
                try {
                    message = mailbox.take();
                } catch (InterruptedException e) {
                    message = null;
                }
            }
            if (message != null) {
                if (message instanceof HaltMessage) {
                    proceed = false;
                    turbo = false;
                } else if (message instanceof ProceedMessage) {
                    proceed = true;
                } else if (message instanceof LoadMessage) {
                    LoadMessage l = (LoadMessage)message;
                    proceed = false;
                    cp.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
                    tc.catseye.yoob.State state = loader.getState(l.name);
                    if (state == null) {
                        cp.displayModalMessage("Couldn't load classes for language '" + l.name + "'", false);
                    } else {
                        cp.selectLanguage(state.getLanguage());
                    }
                    cp.setCursor(null);
                } else if (message instanceof SetTurboMessage) {
                    SetTurboMessage t = (SetTurboMessage)message;
                    this.turbo = t.turbo;
                }
            }
        }
    }
}