package gve.calc.formula;

import java.awt.*;

 Cursor positions: if ^ is visible, cursor pos >=0;
  if ^ is invisible with cursorpos <0, cursor is invisible,
  if ^ is invisible with cursorpos >=0, cursor is at the right of exponent 
public class OperatorPowView extends InfixBinaryOpView {
	public OperatorPowView(OperatorPow model,FormulaView view) {
		super(model,view);
		setLayout(new OperatorPowLayout());
		deactivate();
	}

	public void activate() {}

	public void deactivate() {
		getComponent(1).setVisible(false);
		getOperatorView().setCursorPos(Somewhere_NOWHERE);
		invalidate();
	}

	public void setCursorPos(int pos) {
		FormulaView view = FormulaView.get(this);
		if (pos == Somewhere_NOWHERE) {
			deactivate();
		} else if (pos==0 || pos==1) {
			CursorPosLabel label = (CursorPosLabel)getComponent(1);
			label.setVisible(true);
			invalidate();
			label.setCursorPos(pos);
		} else if (pos == Somewhere_RIGHT) {
			getComponent(1).setVisible(false);
			getOperatorView().setCursorPos(0);
			invalidate();
		} else setCursorPos(0);
	}

	public int getCursorPos() {
		CursorPosLabel center = (CursorPosLabel)getComponent(1);
		if (center.isVisible()) return center.getCursorPos(); 	// 0 or 1
		if (center.getCursorPos() < 0) return Somewhere_NOWHERE;
		return Somewhere_RIGHT;
	}

	public int getBaseline() {
		if (getComponent(1).isVisible()) return super.getBaseline();
		Component left = getComponent(0);
		Component right = getComponent(2);
		int base;
		if (left instanceof HasBaseline) base = ((HasBaseline)left).getBaseline();
		else base = left.getSize().height / 2;
		return base + right.getSize().height;
	}

	public void paint(Graphics g) {
		super.paint(g);
		CursorPosLabel center = (CursorPosLabel)getComponent(1);
		if (!center.isVisible() && center.getCursorPos()>=0) {
			FontMetrics fm = g.getFontMetrics();
			int spatwidth = fm.charWidth(' ');
			Dimension siz = getSize();
g.setColor(Color.green);
			g.fillRect(siz.width-spatwidth,getBaseline()-fm.getAscent(),spatwidth,fm.getHeight());
		}
	}

	public boolean keydn(int key) {
		int cp = getCursorPos();
		FormulaView view = FormulaView.get(this);
		OperatorPow model = (OperatorPow)getModel();
		if (key == Key_LEFT) {
			if (cp == Somewhere_RIGHT) {
				view.setCursorPart(model.right,Somewhere_RIGHT);
				return true;
			}
		} else if (key == Key_RIGHT) {
			if (cp == Somewhere_RIGHT)
				return false;	// cannot move more to the left
			if (cp == Somewhere_NOWHERE && Part.isDescendantOr(view.getCursorPart(),model.right)) {
				// Cursor is at the right of the exponent.
				view.setCursorComp(this,Somewhere_RIGHT);
				return true;
			}
		}
		if (cp == Somewhere_RIGHT) {
			Formula f = view.getFormula();
			switch (key) {
			case '(':	// PENDING
				break;
			default:
				if (key == ' ') {
					Identifier dummy = new Identifier("");
					f.replace(model,dummy);
					OperatorSpace spat;
					f.replace(dummy,spat = new OperatorSpace(model,new Identifier("")));
					view.setCursorPart(spat,0);
//					spat.rotate(f);
					spat.recognizeOp(f);
					return true;
				} else if (key > 32) {
					Identifier dummy = new Identifier("");
					f.replace(model,dummy);
					OperatorSpace spat;
					Identifier ident = new Identifier((char)key);
					f.replace(dummy,spat = new OperatorSpace(model,ident));
					view.setCursorPart(ident,1);
//					spat.rotate(f);
					spat.recognizeOp(f);
					return true;
				}
			}
			return false;
		}
		return super.keydn(key);
	}
}

class OperatorPowLayout extends HorizontalLayoutMgr {
	public void OperatorPowLayout() {}

	public void addLayoutComponent(String name,Component comp) {}

	public void removeLayoutComponent(Component comp) {}

	public Dimension preferredLayoutSize(Container target) {
		CursorPosLabel center = (CursorPosLabel)target.getComponent(1);
		if (center.isVisible()) return super.preferredLayoutSize(target);
		Component left = target.getComponent(0);
		Component right = target.getComponent(2);
		Dimension l = left.getPreferredSize();
		Dimension r = right.getPreferredSize();
		int extra = 0;
		if (center.getCursorPos() >= 0)
			extra = target.getFontMetrics(target.getFont()).charWidth(' ');
		return new Dimension(l.width + r.width + extra,l.height + r.height);
	}

	public Dimension minimumLayoutSize(Container target) {
		return preferredLayoutSize(target);
	}

	public void layoutContainer(Container target) {
		CursorPosLabel center = (CursorPosLabel)target.getComponent(1);
		if (center.isVisible()) {
			super.layoutContainer(target);
			return;
		}
		Component left = target.getComponent(0);
		Component right = target.getComponent(2);
		left.validate();
		right.validate();
		Dimension l = left.getPreferredSize();
		Dimension r = right.getPreferredSize();
		left.setBounds(0,r.height,l.width,l.height);
		right.setBounds(l.width,0,r.width,r.height);
	}
}