import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Scanner;

import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.paint.Color;

public class MyCanvas extends Canvas {
    
    private double width, height;  // Canvas has them, as private
    private GraphicsContext gc;    // Canvas has it, as private
    
    private ArrayList<Stroke> strokes;
    
    public MyCanvas(double w, double h) {
        super(w, h);
        
        width  = w;
        height = h;
        
        gc = super.getGraphicsContext2D();
        
        strokes = new ArrayList<>();
    }
    
    public void addStroke(Stroke s) {
        strokes.add(s);
        
        // must repaint
        paint();
    }
    
    public void clearCanvas() {
        strokes.clear();
        
        paint();
    }
    
    public void paint() {
        // clear canvas
        gc.clearRect(0, 0, width, height);
        
        // draw all strokes in the arraylist
        for (Stroke s : strokes) {
            s.draw(gc);
        }
    }
    
    public void openTextFile(File fh) {
        try {
            Scanner fileIn = new Scanner(fh);    
            
            clearCanvas();
           
            // read the number of strokes in the file
            int nStrokes = fileIn.nextInt();     
            
            for (int i = 0; i < nStrokes; ++i) {
                String type = fileIn.next();
                int    cx   = fileIn.nextInt();
                int    cy   = fileIn.nextInt();
                int    size = fileIn.nextInt();
                
                boolean fill = fileIn.nextBoolean();
                double red   = fileIn.nextDouble();
                double green = fileIn.nextDouble();
                double blue  = fileIn.nextDouble();
                Color color  = Color.color(red, green, blue);
                
                // based on the stroke type, create different strokes
                Stroke s = null;
                if (type.equals("C")) {
                    s = new CircularStroke(cx, cy, size, fill, color);
                } 
                else if (type.equals("S")) {
                    s = new SquareStroke(cx, cy, size, fill, color);
                }
                
                if (s != null) {
                    strokes.add(s);
                }
            }
            
            paint();
            fileIn.close();
        } 
        catch(FileNotFoundException e1) {
            System.err.println(fh.getName() + " not found in the current folder");
            e1.printStackTrace();
        } 
        catch(Exception e3) {
            System.err.println("Some error loading a drawing from " + fh.getName());
            e3.printStackTrace();
        }
    }
    
    // allows user to save current drawing (canvas) into a text file
    // format:
    // #_of_strokes
    // C cx cy size filled r g b
    // S cx cy size filled r g b
    public void saveTextFile(File fh) {
        
        try {
            PrintWriter fileOut = new PrintWriter(fh);
        
            fileOut.println(strokes.size());
            
            for (Stroke s : strokes) {
                fileOut.println(s.toString());
            }
        
            fileOut.close();
        }
        catch(IOException e) {
            System.err.println("Error writing to " + fh.getName());
            e.printStackTrace();
        }
        
    }
    
}