import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.*;
import java.util.ArrayList;
import java.util.regex.*;
import javax.swing.*;


@SuppressWarnings("serial")
public class RobotRouteFrame extends JFrame implements ActionListener
{
    private RobotRouteWorld m_objWorld = null;                                // Draws everything.
    private RobotRouteScriptFrame m_objScript = null;                         // Script JFrame.
    private Robot m_objRobot = null;                                          // Robot.
    private boolean m_bUseTrig = false;                                       // Use trigonometry or not?

    /**
     * Constructor.
     * @param strTitle Frame title.
     */
    public RobotRouteFrame(String strTitle)
    {
        super(strTitle);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // Objects.
        m_objRobot  = new Robot();
        m_objWorld  = new RobotRouteWorld();
        m_objScript = new RobotRouteScriptFrame("Script Output");
        m_objScript.pack();

        // Associate the robot with the world.
        m_objWorld.setRobot(m_objRobot);

        // Create layout.
        createComponents();
    }

    /**
     * Create components and add to content pane.
     */
    public void createComponents()
    {
        JPanel objMainPanel = new JPanel(new GridLayout(1, 1));
        JPanel objBtnPanel = new JPanel(new GridLayout(1, 0));

        // Create the buttons.
        JButton btnLandmarks = new JButton("Load Landmarks");
        JButton btnWaypoints = new JButton("Load Waypoints");
        JButton btnResetGUI = new JButton("Reset World");
        JButton btnViewScript = new JButton("View Script");
        JButton btnViewStats = new JButton("View Statistics");

        // Set the actions.
        btnLandmarks.addActionListener(this);
        btnLandmarks.setActionCommand("landmarks");
        btnWaypoints.addActionListener(this);
        btnWaypoints.setActionCommand("waypoints");
        btnViewScript.addActionListener(this);
        btnViewScript.setActionCommand("script");
        btnViewStats.addActionListener(this);
        btnViewStats.setActionCommand("stats");
        btnResetGUI.addActionListener(this);
        btnResetGUI.setActionCommand("reset");

        // Add the buttons to the panel.
        objBtnPanel.add(btnLandmarks);
        objBtnPanel.add(btnWaypoints);
        objBtnPanel.add(btnViewScript);
        objBtnPanel.add(btnViewStats);
        objBtnPanel.add(btnResetGUI);

        // Add the World to the main panel.
        objMainPanel.add(m_objWorld);

        // Add our main panel.
        getContentPane().add(objMainPanel, BorderLayout.CENTER);
        getContentPane().add(objBtnPanel, BorderLayout.PAGE_END);

        // Can we load anything right away?
        CheckForFiles();
    }

    /**
     * Check if we have existing landmarks/waypints files in the current directory.
     */
    private void CheckForFiles()
    {
        File fTmpL = new File(".//landmarks.dat");
        File fTmpW = new File(".//waypoints.dat");

        // See if we can load a landmarks file.
        if (fTmpL.exists() && fTmpL.canRead() && fTmpL.isFile())
        {
            if (JOptionPane.showConfirmDialog(null,
                    "A landmarks.dat file has been discovered. Would you like to load it?", "Question:",
                    JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION)
            {
                ParseLandmarksFile(fTmpL);
            }
        }

        // See if we can load a waypoints file.
        if (fTmpW.exists() && fTmpW.canRead() && fTmpW.isFile())
        {
            if (JOptionPane.showConfirmDialog(null,
                    "A waypoints.dat file has been discovered. Would you like to load it?", "Question:",
                    JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION)
            {
                // Trig or not.
                if (JOptionPane.showConfirmDialog(null, "Trigonometry (yes) or non-trigonometry (no)?", "Question:",
                    JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION)
                    m_bUseTrig = true;
                else
                    m_bUseTrig = false;

                // Load!
                ParseWaypointsFile(fTmpW);
            }
        }
    }

    /**
     * Load landmarks from a .dat file.
     */
    private void LoadLandmarks()
    {
        JFileChooser objFile = new JFileChooser();

        objFile.setAcceptAllFileFilterUsed(false);
        objFile.setDialogTitle("Choose Landmarks Data File");
        objFile.addChoosableFileFilter(new RobotRouteFileFilter());

        // Open the dialog.
        int iRes = objFile.showOpenDialog(this);
        if (iRes == JFileChooser.APPROVE_OPTION)
            ParseLandmarksFile(objFile.getSelectedFile());
    }

    /**
     * Load waypoints from a .dat file.
     */
    private void LoadWaypoints()
    {
        JFileChooser objFile = new JFileChooser();

        objFile.setAcceptAllFileFilterUsed(false);
        objFile.setDialogTitle("Choose Waypoints Data File");
        objFile.addChoosableFileFilter(new RobotRouteFileFilter());

        // Open the dialog.
        int iRes = objFile.showOpenDialog(this);
        if (iRes == JFileChooser.APPROVE_OPTION)
        {
            if (JOptionPane.showConfirmDialog(null,
                "Trigonometry (yes) or non-trigonometry (no)?",
                "Question:",
                JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION)
                m_bUseTrig = true;
            else
                m_bUseTrig = false;
            ParseWaypointsFile(objFile.getSelectedFile());
        }
    }

    /**
     * Parse the landmarks file.
     * @param objData File object.
     */
    private void ParseLandmarksFile(File objData)
    {
        BufferedReader objBuff = null;
        try
        {
            // Check file name.
            if (!objData.getName().equalsIgnoreCase("landmarks.dat"))
                throw new Exception("Invalid file name. Must be \"landmarks.dat\".");

            // Make sure we can read the file.
            if (objData.isFile() && objData.canRead())
            {
                // Read the file. Hopefully it contains landmarks!
                objBuff = new BufferedReader(new FileReader(objData));

                // Look for things we recognise.
                Pattern objPatn = Pattern.compile("(\\d{1,2})\\s+(\\d{1,2})\\s+(.+)");
                final ArrayList<Landmark> arrLM = new ArrayList<Landmark>();
                String strBuff;

                // Read line by line.
                while ((strBuff = objBuff.readLine()) != null)
                {
                    Matcher objMatch = objPatn.matcher(strBuff);
                    if (objMatch.find() && objMatch.groupCount() == 3)
                    {
                        String strX = objMatch.group(1);
                        String strY = objMatch.group(2);
                        String strName = objMatch.group(3);

                        try
                        {
                            arrLM.add(new Landmark(
                                Integer.parseInt(strX),
                                Integer.parseInt(strY), strName
                            ));
                        }

                        // Skip bad input.
                        catch (NumberFormatException nfe)
                        {
                            ShowError("Invalid landmark detected - ignoring.");
                            continue;
                        }
                    }
                }

                // Set landmarks.
                m_objRobot.setLandmarks(arrLM);
                m_objWorld.drawLandmarks(arrLM);
            }
            else
                throw new Exception("The selected file cannot be read.");
        }
        catch (Exception e)
        {
            ShowError(e.getMessage());
        }
        finally
        {
            try { if (objBuff != null) objBuff.close(); } catch (Exception e) {}
        }
    }

    /**
     * Load waypoints from a .dat file.
     */
    private void ParseWaypointsFile(File objData)
    {
        BufferedReader objBuff = null;
        try
        {
            // Check file name.
            if (!objData.getName().equalsIgnoreCase("waypoints.dat"))
                throw new Exception("Invalid file name. Must be \"waypoints.dat\".");

            // Make sure we can read the file.
            if (objData.isFile() && objData.canRead())
            {
                // Read the file. Hopefully it contains waypoints!
                objBuff = new BufferedReader(new FileReader(objData));

                // Look for things we understand.
                Pattern objPatn = Pattern.compile("(\\d{1,2})\\s+(\\d{1,2})");
                ArrayList<int[]> arrWP = new ArrayList<int[]>();
                String strBuff;

                // Read line by line.
                while ((strBuff = objBuff.readLine()) != null)
                {
                    Matcher objMatch = objPatn.matcher(strBuff);
                    if (objMatch.find() && objMatch.groupCount() == 2)
                    {
                        String strX = objMatch.group(1);
                        String strY = objMatch.group(2);

                        try
                        {
                            arrWP.add(new int[] {
                                Integer.parseInt(strX),
                                Integer.parseInt(strY)
                            });
                        }

                        // Skip bad input.
                        catch (NumberFormatException nfe)
                        {
                            ShowError("Invalid waypoint detected - ignoring.");
                            continue;
                        }
                    }
                }

                // Get the robot to do its thing.
                m_objRobot.setWorld(m_objWorld);
                m_objRobot.setWaypoints(arrWP);

                m_objWorld.setRobot(m_objRobot);
                m_objWorld.drawRoute(arrWP, m_bUseTrig);

                // Need to draw route first (if using trig).
                m_objRobot.doFollowRoute(m_bUseTrig);

                // Set script.
                m_objScript.m_txtScript.setText(m_objRobot.getScriptAsString("\r\n"));
            }
            else
                throw new Exception("The selected file cannot be read.");
        }
        catch (Exception e)
        {
            ShowError(e.getMessage());
        }
        finally
        {
            try { if (objBuff != null) objBuff.close(); } catch (Exception e) {}
        }
    }

    /**
     * Show an error dialog.
     * @param strErr Error message.
     */
    private void ShowError(String strErr)
    {
        JOptionPane.showMessageDialog(this, strErr, "Error:",
            JOptionPane.ERROR_MESSAGE
        );
    }

    /**
     * Perform an action.
     */
    @Override
    public void actionPerformed(ActionEvent arg)
    {
        // Perform an action.
        if (arg.getActionCommand().equals("landmarks"))
            LoadLandmarks();

        // Load waypoints.
        else if (arg.getActionCommand().equals("waypoints"))
            LoadWaypoints();

        // Reset GUI.
        else if (arg.getActionCommand().equals("reset"))
        {
            m_objWorld.resetGUI();
            m_objRobot.resetRobot();
            m_objScript.setScript(m_objRobot.getScript());
        }

        // Script.
        else if (arg.getActionCommand().equals("script"))
        {
            m_objScript.setScript(m_objRobot.getScript());
            m_objScript.setVisible(true);
        }

        // Stats.
        else if (arg.getActionCommand().equals("stats"))
        {
            String strMsg = "Statistics:\n\n";
            if (m_bUseTrig)
            {
                // Landmarks.
                ArrayList<Landmark> arrLM = m_objRobot.getSeenLandmarksTrig();

                strMsg += "Landmarks:\n====================================\n";
                if (arrLM != null && arrLM.size() > 0)
                {
                    for (Landmark objLM : arrLM)
                        strMsg += "Saw \"" + objLM.getName() + "\" at (" + objLM.getX() + ", " + objLM.getY() + ")\n";
                }
                else
                    strMsg += "Saw no landmarks.\n";

                // Distance.
                double dDistU = m_objRobot.getDistanceTravelled();
                double dDistP = m_objRobot.getDistanceTravelledInPixels();
                strMsg += "\nDistance:\n====================================\n";
                strMsg += "Distance Travelled: " + dDistU; // + " (" + dDistP + " pixels)";
            }
            else
            {
                // Landmarks.
                ArrayList<Landmark> arrLM = m_objRobot.getSeenLandmarks();

                strMsg += "Landmarks:\n====================================\n";
                if (arrLM != null && arrLM.size() > 0)
                {
                    for (Landmark objLM : arrLM)
                        strMsg += "Saw \"" + objLM.getName() + "\" at (" + objLM.getX() + ", " + objLM.getY() + ")\n";
                }
                else
                    strMsg += "Saw no landmarks.\n";

                // Distance.
                int iDist = (int)m_objRobot.getDistanceTravelled();
                strMsg += "\nDistance:\n====================================\n";
                strMsg += "Distance Travelled: " + iDist;
            }
            JOptionPane.showMessageDialog(null, strMsg);
        }
    }
}