/*[Update:[Fri Oct 15 IST 2021]]
 **Mon Oct 11 2021
 Now showMarks accepts the localStart explicitly. So we are not querying Finalize
 from paintComponent for the current line.
 */
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.*;

public class TrackBar extends JPanel 
    implements MouseListener {
    private Finalise f;
    Vector<ColPos> pos=new Vector<ColPos>();
    int curr = -1;

    public TrackBar(Finalise fnl) {
        f = fnl;
        setBackground(new Color(175,202,202));
        addMouseListener(this);
   }

    private int tot;

    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.setColor(Color.BLACK);
        tot = f.nLines();
        if(tot <= 0) return;
        if(pos==null) return;
        for(ColPos cp : pos) {
            int y = (int)((cp.pos/(float)tot) * getHeight());
            g.setColor(cp.col);
            g.drawLine(0,y,getWidth(),y);
        }
        int y = (int)((localStart/(float)tot) * getHeight());
        g.setColor(Color.RED);
        g.drawLine(0,y,getWidth(),y);
    }


    private int localStart = -1, colIndex;
    public void showMarks(Vector<Integer> p, int locStart) {
        pos.clear();
        colIndex = 0;
        localStart = locStart;
        //System.err.println("Show marks.");
        addMarks(p);
    }

    public void addMarks(Vector<Integer> p) {
        //System.err.println("Add marks.");
        if(p!=null) {
            for(int i : p) {
                pos.add(new ColPos(colIndex,i));
            }
            colIndex++;
        }
        repaint();
    }


    public void mouseClicked(MouseEvent me) {
        int y = me.getY();
        int which = (int)(y/(float) getHeight() * tot);

        if(me.getButton()==MouseEvent.BUTTON3) {
            if(localStart>=0) f.goToLine(localStart, false);
            return;
        }

        int minDiff = tot+1;
        int best = -1;

        for(ColPos cp : pos) {
            int i = cp.pos;
            int diff = i-which;
            if(diff < 0) diff = -diff;
            if(diff < minDiff) {
                minDiff = diff;
                best = i;
            }
        }

        //f.getGlassPane().setVisible(true);
        f.goToLine(best, false);
    }

    public void mousePressed(MouseEvent me) {}
    public void mouseReleased(MouseEvent me) {}
    public void mouseEntered(MouseEvent me) {}
    public void mouseExited(MouseEvent me) {}
}

class ColPos {
    Color col;
    int pos;
    private static Color colList[] = {Color.BLACK,Color.YELLOW,Color.GREEN,Color.MAGENTA};
    ColPos(int ci, int p) {
        col = colList[ci<4? ci: 3];
        pos = p;
    }
}