package org.r3pek.pharmacies.widgets;

import org.r3pek.pharmacies.R;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.Display;
import android.view.View;
import android.view.WindowManager;

public class Compass extends View implements ImageOrientationSensor {
	
	/* Orientation
	 * 0 -> portrait
	 * 1 -> landscape
	 * 2 -> inverted portrait
	 * 3 -> inverted landscape
	 */
	private final int orientationCompensation[] = {0, 90, 180, 270};
	
	private Context ctx;
	private float bearing;
	private float orientation;
	private Drawable needleBackgound;
	private Drawable needle;

	public Compass(Context context) {
		super(context);

		ctx = context;
		setDrawable();
	}

	public Compass(Context context, AttributeSet attrs) {
		super(context, attrs);

		ctx = context;
		setDrawable();
	}

	public Compass(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);

		ctx = context;
		setDrawable();
	}
	
	private void setDrawable() {
		needleBackgound = ctx.getResources().getDrawable(R.drawable.compass_background);
		needle = ctx.getResources().getDrawable(R.drawable.compass_needle);
	}
	
	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		
		Display display = ((WindowManager)ctx.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
		
		float rotation = bearing - orientation - orientationCompensation[display.getOrientation()] - 45;
				
		float keyPoints[] = {-4, 4, 4, -4};
		Matrix matrix = new Matrix();
		matrix.preRotate(rotation);
		matrix.mapPoints(keyPoints);
	    float maxX, maxY;
	    maxX = maxY = Float.MIN_VALUE;
	    float minX, minY;
	    minX = minY = Float.MAX_VALUE;
	    for (int i = 0; i < keyPoints.length; i++) {
	      if (i % 2 == 0) {
	    	  if (maxX < keyPoints[i]) maxX = keyPoints[i];
	    	  if (minX > keyPoints[i]) minX = keyPoints[i];
	      } else {
	    	  if (maxY < keyPoints[i]) maxY = keyPoints[i];
	    	  if (minY > keyPoints[i]) minY = keyPoints[i];
	      }
	    }
		
	    canvas.save();
		needleBackgound.setBounds(0, 0, 15, 15);
		needleBackgound.draw(canvas);
		canvas.translate((maxX + minX) / -2f, (maxY + minY) / -2f);
		canvas.rotate(rotation, 8, 8);
		needle.setBounds(0, 0, 15, 15);
		needle.draw(canvas);
		canvas.restore();
	}
	
	public void setBearing(float bearing) {
		this.bearing = bearing;
	}

	public void setOrientation(float orientation) {
		this.orientation = orientation;
		postInvalidate();
	}
	
}