//
//  GDInterface.java
//  Java Graphics Device
//
//  Created by Simon Urbanek on Thu Aug 05 2004.
//  Copyright (c) 2004 Simon Urbanek. All rights reserved.
//
//

package org.rosuda.javaGD;

import java.awt.*;
import java.lang.reflect.Method;

/*---- external API: those methods are called via JNI from the GD C code

public void     gdOpen(int devNr, double w, double h);
public void     gdActivate();
public void     gdCircle(double x, double y, double r);
public void     gdClip(double x0, double x1, double y0, double y1);
public void     gdClose();
public void     gdDeactivate();
public void     gdHold();
public double[] gdLocator();
public void     gdLine(double x1, double y1, double x2, double y2);
public double[] gdMetricInfo(int ch);
public void     gdMode(int mode);
public void     gdNewPage(int deviceNumber);
public void     gdPolygon(int n, double[] x, double[] y);
public void     gdPolyline(int n, double[] x, double[] y);
public void     gdRect(double x0, double y0, double x1, double y1);
public double[] gdSize();
public double   gdStrWidth(String str);
public void     gdText(double x, double y, String str, double rot, double hadj);

-- GDC - manipulation of the current graphics state
    public void gdcSetColor(int cc);
    public void gdcSetFill(int cc);
    public void gdcSetLine(double lwd, int lty);
    public void gdcSetFont(double cex, double ps, double lineheight, int fontface, String fontfamily);

-- implementation --*/

public class GDInterface {
    public boolean active=false;
    public boolean open=false;
    int devNr=-1;
    
    public GDContainer c=null;
    public LocatorSync ls=null;
    
    public void     gdOpen(double w, double h) {
        open=true;
    }

    public void     gdActivate() {
        active=true;
    }

    public void     gdCircle(double x, double y, double r) {
        if (c==null) return;
        c.add(new GDCircle(x,y,r));
    }

    public void     gdClip(double x0, double x1, double y0, double y1) {
        if (c==null) return;
        c.add(new GDClip(x0, y0, x1, y1));
    }

    public void     gdClose() {
        if (c!=null) c.closeDisplay();
        open=false;
    }

    public void     gdDeactivate() {
        active=false;
    }

    public void     gdHold() {
    }

    public double[] gdLocator() {
	if (c==null) return null;
	if (ls==null) ls=new LocatorSync();
	if (!c.prepareLocator(ls)) return null;
        return ls.waitForAction();
    }

    public void     gdLine(double x1, double y1, double x2, double y2) {
        if (c==null) return;
        c.add(new GDLine(x1, y1, x2, y2));
    }

    public double[] gdMetricInfo(int ch) {
        double[] res=new double[3];
        double ascent=0.0, descent=0.0, width=8.0;
        if (c!=null) {
            Graphics g=c.getGraphics();
            if (g!=null) {
                Font f=c.getGState().f;
                if (f!=null) {
                    FontMetrics fm=g.getFontMetrics(c.getGState().f);
                    if (fm!=null) {
                        ascent=(double) fm.getAscent();
                        descent=(double) fm.getDescent();
                        width=(double) fm.charWidth((ch==0)?77:ch);
                    }
                }
            }
        }
        res[0]=ascent; res[1]=descent; res[2]=width;
        return res;
    }

    public void     gdMode(int mode) {
        if (c!=null) c.syncDisplay(mode==0);
    }

    public void     gdNewPage() {
        if (c!=null) c.reset();
    }

    public void     gdNewPage(int devNr) { // new API: provides the device Nr.
        this.devNr=devNr;
        if (c!=null) {
            c.reset();
            c.setDeviceNumber(devNr);
        }
    }

    public void     gdPolygon(int n, double[] x, double[] y) {
        if (c==null) return;
        c.add(new GDPolygon(n, x, y, false));
    }

    public void     gdPolyline(int n, double[] x, double[] y) {
        if (c==null) return;
        c.add(new GDPolygon(n, x, y, true));
    }

    public void     gdRect(double x0, double y0, double x1, double y1) {
        if (c==null) return;
        c.add(new GDRect(x0, y0, x1, y1));
    }

    public double[] gdSize() {
        double[] res=new double[4];
        double width=0d, height=0d;
        if (c != null) {
            Dimension d = c.getSize();
            width = d.getWidth();
            height = d.getHeight();
        }
        res[0]=0d;
        res[1]=width;
        res[2]=height;
        res[3]=0;
        return res;
    }

    public double   gdStrWidth(String str) {
        double width=(double)(8*str.length()); // rough estimate
        if (c!=null) { // if canvas is active, we can do better
            Graphics g=c.getGraphics();
            if (g!=null) {
                Font f=c.getGState().f;
                if (f!=null) {
                    FontMetrics fm=g.getFontMetrics(f);
                    if (fm!=null) width=(double)fm.stringWidth(str);
                }
            }
        }
        return width;
    }

    public void     gdText(double x, double y, String str, double rot, double hadj) {
        if (c==null) return;
        c.add(new GDText(x, y, rot, hadj, str));
    }

    /*-- GDC - manipulation of the current graphics state */
    public void gdcSetColor(int cc) {
        if (c==null) return;
        c.add(new GDColor(cc));
    }

    public void gdcSetFill(int cc) {
        if (c==null) return;
        c.add(new GDFill(cc));
    }

    public void gdcSetLine(double lwd, int lty) {
        if (c==null) return;
        c.add(new GDLinePar(lwd, lty));
    }

    public void gdcSetFont(double cex, double ps, double lineheight, int fontface, String fontfamily) {
        if (c==null) return;
        GDFont f=new GDFont(cex, ps, lineheight, fontface, fontfamily);
        c.add(f);
        c.getGState().f=f.getFont();
    }

    public int getDeviceNumber() { return (c==null)?devNr:c.getDeviceNumber(); }

    public void executeDevOff() {
        if (c==null || c.getDeviceNumber()<0) return;
        try { // for now we use no cache - just pure reflection API for: Rengine.getMainEngine().eval("...")
            Class cl=Class.forName("org.rosuda.JRI.Rengine");
            if (cl==null)
                System.out.println(">> can't find Rengine, close function disabled. [c=null]");
            else {
                Method m=cl.getMethod("getMainEngine",null);
                Object o=m.invoke(null,null);
                if (o!=null) {
                    Class[] par=new Class[1];
                    par[0]=Class.forName("java.lang.String");
                    m=cl.getMethod("eval",par);
                    Object[] pars=new Object[1];
                    pars[0]="try({ dev.set("+(c.getDeviceNumber()+1)+"); dev.off()},silent=TRUE)";
                    m.invoke(o, pars);
                }
            }
        } catch (Exception e) {
            System.out.println(">> can't find Rengine, close function disabled. [x:"+e.getMessage()+"]");
        }
    }    
}