package uu.mal.skate.view;

import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;

import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSeparator;
import javax.swing.JTextField;

import uu.mal.skate.model.Options;
import uu.mal.skate.simtype.AdaptiveEpsilonGreedy;
import uu.mal.skate.simtype.EpsilonDecreasing;
import uu.mal.skate.simtype.EpsilonFirst;
import uu.mal.skate.simtype.EpsilonGreedy;
import uu.mal.skate.simtype.LinearUpdate;

public class OptionsDialog extends JDialog {

	private static final long serialVersionUID = 1L;

	public static final int ACTION_CANCEL = 0;
	public static final int ACTION_START = 1;

	private final Options options;
	private int action = ACTION_CANCEL;

	//private final OptionsField simName;
	private final OptionsField epsilon;
	private final OptionsField rewardMove;
	private final OptionsField rewardCollide;
	private final OptionsField directionCount;
	private final OptionsField torusWidth;
	private final OptionsField torusHeight;
	private final OptionsField agentCount;
	private final OptionsField agentCollision;
	private final OptionsField agentSpeed;
	private final OptionsField simSpeed;
	private final OptionsField epsilonFirstN;
	private final OptionsField epsilonDecrease;
	private final OptionsField maximumW;
	private final OptionsField lambda;
	private final OptionsField alpha;
	private final OptionsField sigma;

	private final JComboBox<String> simTypes;
	private final JCheckBox subtlyImprove;

	private final JButton btnStart;
	private final JButton btnCancel;

	private final JPanel pane = new JPanel();

	public OptionsDialog(JFrame frame, Options options) {
		super(frame, true);
		if(options == null)
			options = Options.defaultOptions();
		this.options = options;

		setTitle("New simulation");

		//simName = new OptionsField("Simulation name", "", "Unused at the moment");
		epsilon = new OptionsField("Epsilon", options.epsilon, "Exploration probability");
		rewardMove = new OptionsField("Move reward", options.rewardMove);
		rewardCollide = new OptionsField("Collision reward", options.rewardCollide);
		directionCount = new OptionsField("Nr of directions", options.directionCount);
		torusWidth = new OptionsField("Torus width", options.torusWidth);
		torusHeight = new OptionsField("Torus height", options.torusHeight);
		agentCount = new OptionsField("Nr of agents", options.agentCount);
		agentCollision = new OptionsField("Collision radius", options.agentCollision);
		agentSpeed = new OptionsField("Agent speed", options.agentSpeed);
		simSpeed = new OptionsField("Simulation speed", options.simSpeed, "Number of simulation iterations per second.");
		epsilonFirstN = new OptionsField("Epsilon first N", options.epsilonFirstN, "Explore first N iterations, after this only exploit.");
		epsilonFirstN.setEnabled(false);
		epsilonDecrease = new OptionsField("Epsilon decreasing factor (> 0)", options.epsilonDecrease, "Low numbers will cause exploration to quicly drop.");
		epsilonDecrease.setEnabled(false);
		maximumW = new OptionsField("Maximum w (>= 0)", options.maximumW, "Random noise will be between 0 and this value. <br/> Set to 0 to disable.");
		maximumW.setEnabled(false);
		lambda = new OptionsField("Discount factor [0, 1]", options.lambda);
		lambda.setEnabled(false);
		alpha = new OptionsField("Temporal-difference Error modifier (0,1]", options.alpha, "Modifies the difference between the current reward and the learned estimate.");
		alpha.setEnabled(false);
		sigma = new OptionsField("Inverse sensitivity (> 0)", options.sigma, "Low inverse sensitivities cause full exploration even at small value changes. <BR/> On the other hand, high inverse sensitivities cause a hight level of exploration only at large value changes.");
		sigma.setEnabled(false);
		
		subtlyImprove = new JCheckBox("Subtly improve");
		
		simTypes = new JComboBox<>(new String[] { 
				EpsilonGreedy.class.getSimpleName(),
				AdaptiveEpsilonGreedy.class.getSimpleName(),
				EpsilonFirst.class.getSimpleName(), 
				EpsilonDecreasing.class.getSimpleName(), 
				LinearUpdate.class.getSimpleName()
				});
		simTypes.addItemListener(new SimTypeChosenAction());
		simTypes.setSelectedItem(options.simType);
		JPanel simTypePanel = new JPanel();
		simTypePanel.setLayout(new FlowLayout(FlowLayout.RIGHT));
		simTypePanel.add(new JLabel("Simulation type"));
		simTypePanel.add(simTypes);
		
		JPanel improvePanel = new JPanel();
		improvePanel.setLayout(new FlowLayout(FlowLayout.RIGHT));
		improvePanel.add(subtlyImprove);

		btnStart = new JButton("Create");
		btnStart.addActionListener(new StartSimAction());
		btnCancel = new JButton("Cancel");
		btnCancel.addActionListener(new CancelAction());
		JPanel btnPanel = new JPanel();
		GridBagLayout btnLayout = new GridBagLayout();
		GridBagConstraints c = new GridBagConstraints();
		c.fill = GridBagConstraints.HORIZONTAL;
		btnPanel.setLayout(btnLayout);
		c.weightx = 0.5;
		c.gridx = 0;
		c.gridy = 0;
		btnPanel.add(btnCancel, c);
		c.gridx = 1;
		c.gridy = 0;
		btnPanel.add(btnStart, c);

		BoxLayout l = new BoxLayout(pane, BoxLayout.Y_AXIS);
		pane.setLayout(l);
		pane.add(simTypePanel);
		//pane.add(simName);
		pane.add(new JSeparator());
		pane.add(epsilon);
		pane.add(epsilonFirstN);
		pane.add(epsilonDecrease);
		pane.add(new JSeparator());
		pane.add(alpha);
		pane.add(sigma);
		pane.add(new JSeparator());
		pane.add(lambda);
		pane.add(maximumW);
		pane.add(new JSeparator());
		pane.add(rewardMove);
		pane.add(rewardCollide);
		pane.add(directionCount);
		pane.add(torusWidth);
		pane.add(torusHeight);
		pane.add(agentCount);
		pane.add(agentCollision);
		pane.add(agentSpeed);
		pane.add(simSpeed);
		pane.add(improvePanel);
		pane.add(btnPanel);

		setContentPane(pane);

		pack();

		setVisible(true);
	}

	public int getAction() {
		return action;
	}

	public Options getOptions() {
		options.epsilon = epsilon.getDoubleValue();
		options.epsilonFirstN = epsilonFirstN.getIntValue();
		options.epsilonDecrease = epsilonDecrease.getDoubleValue();
		options.agentCollision = agentCollision.getIntValue();
		options.agentCount = agentCount.getIntValue();
		options.agentSpeed = agentSpeed.getIntValue();
		options.directionCount = directionCount.getIntValue();
		options.rewardCollide = rewardCollide.getIntValue();
		options.rewardMove = rewardMove.getIntValue();
		options.simSpeed = simSpeed.getIntValue();
		options.torusHeight = torusHeight.getIntValue();
		options.torusWidth = torusWidth.getIntValue();
		options.lambda = lambda.getDoubleValue();
		options.alpha = alpha.getDoubleValue();
		options.sigma = sigma.getDoubleValue();
		options.maximumW = maximumW.getDoubleValue();
		
		options.simType = (String) simTypes.getSelectedItem();
		options.subtlyImprove = subtlyImprove.isSelected();
		options.directions = new double[options.directionCount];
		double n = 2 * Math.PI / options.directionCount;
		for (int i = 0; i < options.directionCount; i++) {
			options.directions[i] = i * n;
		}

		return options;
	}

	private class CancelAction implements ActionListener {
		@Override
		public void actionPerformed(ActionEvent event) {
			action = ACTION_CANCEL;
			OptionsDialog.this.dispose();
		}
	}

	private class SimTypeChosenAction implements ItemListener {
		@Override
		public void itemStateChanged(ItemEvent event) {
			if (event.getStateChange() == ItemEvent.SELECTED) {
				String item = (String) event.getItem();
				epsilon.setEnabled(item.equals(EpsilonGreedy.class.getSimpleName())
						|| item.equals(EpsilonFirst.class.getSimpleName()));
				epsilonFirstN.setEnabled(item.equals(EpsilonFirst.class.getSimpleName()));
				epsilonDecrease.setEnabled(item.equals(EpsilonDecreasing.class.getSimpleName()));
				lambda.setEnabled(item.equals(LinearUpdate.class.getSimpleName()));
				maximumW.setEnabled(item.equals(LinearUpdate.class.getSimpleName()));
				alpha.setEnabled(item.equals(AdaptiveEpsilonGreedy.class.getSimpleName()));
				sigma.setEnabled(item.equals(AdaptiveEpsilonGreedy.class.getSimpleName()));
				
				if(item.equals(LinearUpdate.class.getSimpleName())) {
					if(rewardMove.getIntValue() < 0) {
						rewardMove.setIntValue(0);
					}
					if(rewardCollide.getIntValue() < 0) {
						rewardCollide.setIntValue(0);
					}
				}
			}
		}
	}

	private class StartSimAction implements ActionListener {
		@Override
		public void actionPerformed(ActionEvent event) {
			if(simTypes.getSelectedIndex() >= 0) {
				action = ACTION_START;
				OptionsDialog.this.dispose();	
			}

		}
	}

	private class OptionsField extends JPanel {
		private static final long serialVersionUID = -2926412308706126069L;

		private final JTextField txtField;
		private final JLabel label;

		public void setEnabled(boolean b) {
			txtField.setEnabled(b);
		}
		public OptionsField(String name, double value, String tooltip) {
			this(name, Double.toString(value), tooltip);
		}
		public OptionsField(String name, double value) {
			this(name, Double.toString(value));
		}
		public OptionsField(String name, int value, String tooltip) {
			this(name, Integer.toString(value), tooltip);
		}
		public OptionsField(String name, int value) {
			this(name, Integer.toString(value));
		}

		public double getDoubleValue() {
			return Double.parseDouble(txtField.getText());
		}

		public int getIntValue() {
			return Integer.parseInt(txtField.getText());
		}
		
		@SuppressWarnings("unused")
		public void setDoubleValue(double value) {
			this.setValue(Double.toString(value));
		}
		
		public void setIntValue(int value) {
			this.setValue(Integer.toString(value));
		}
		
		public void setValue(String value) {
			txtField.setText(value);
		}
		
		public OptionsField(String name, String value, String tooltip) {
			this(name, value);
			setToolTipText("<html><head><style></style></head><p>" +tooltip+"</p></html>");
		}

		public OptionsField(String name, String value) {
			txtField = new JTextField(value);
			label = new JLabel(name);
			txtField.setColumns(12);

			setLayout(new FlowLayout(FlowLayout.RIGHT));

			add(label);
			add(txtField);
		}
	}
}