package android.graphics;

public class Canvas {
	public long cairo_context;
	public long widget;

	public Canvas() {}

	public Canvas(long cairo_context, long widget) {
		this.cairo_context = cairo_context;
		this.widget = widget;
	}

	// FIXME: are these _needed_ ?

    public int save() {
		native_save(cairo_context, widget);
		return -1; // FIXME: wtf should we return
	}
    public void restore() {
		native_restore(cairo_context, widget);
	}

	private static native void native_save(long cairo_context, long widget);
	private static native void native_restore(long cairo_context, long widget);

// ---

    /**
     * Draw the specified Rect using the specified paint. The rectangle will
     * be filled or framed based on the Style in the paint.
     *
     * @param rect  The rect to be drawn
     * @param paint The paint used to draw the rect
     */
    public void drawRect(RectF rect, Paint paint) {
//        native_drawRect(mNativeCanvas, rect, paint.mNativePaint);
    }

    /**
     * Draw the specified Rect using the specified Paint. The rectangle
     * will be filled or framed based on the Style in the paint.
     *
     * @param r        The rectangle to be drawn.
     * @param paint    The paint used to draw the rectangle
     */
    public void drawRect(Rect r, Paint paint) {
        drawRect(r.left, r.top, r.right, r.bottom, paint);
    }
    

    /**
     * Draw the specified Rect using the specified paint. The rectangle will
     * be filled or framed based on the Style in the paint.
     *
     * @param left   The left side of the rectangle to be drawn
     * @param top    The top side of the rectangle to be drawn
     * @param right  The right side of the rectangle to be drawn
     * @param bottom The bottom side of the rectangle to be drawn
     * @param paint  The paint used to draw the rect
     */
    public void drawRect(float left, float top, float right, float bottom, Paint paint) {
//        native_drawRect(mNativeCanvas, left, top, right, bottom, paint.mNativePaint);
    }

// ---
    /**
     * Preconcat the current matrix with the specified rotation.
     *
     * @param degrees The amount to rotate, in degrees
     */
    public void rotate(float degrees) {
		native_rotate(cairo_context, widget, degrees);
	}

    /**
     * Preconcat the current matrix with the specified rotation.
     *
     * @param degrees The amount to rotate, in degrees
     * @param px The x-coord for the pivot point (unchanged by the rotation)
     * @param py The y-coord for the pivot point (unchanged by the rotation)
     */
    public final void rotate(float degrees, float px, float py) {
		native_rotate_and_translate(cairo_context, widget, degrees, px, py);
    }
// ---
    /**
     * Draw the text, with origin at (x,y), using the specified paint. The
     * origin is interpreted based on the Align setting in the paint.
     *
     * @param text  The text to be drawn
     * @param x     The x-coordinate of the origin of the text being drawn
     * @param y     The y-coordinate of the origin of the text being drawn
     * @param paint The paint used for the text (e.g. color, size, style)
     */
    public void drawText(String text, float x, float y, Paint paint) {
/*        native_drawText(mNativeCanvas, text, 0, text.length(), x, y, paint.mBidiFlags,
                paint.mNativePaint);*/
    }

    /**
     * Draw the text, with origin at (x,y), using the specified paint.
     * The origin is interpreted based on the Align setting in the paint.
     *
     * @param text  The text to be drawn
     * @param start The index of the first character in text to draw
     * @param end   (end - 1) is the index of the last character in text to draw
     * @param x     The x-coordinate of the origin of the text being drawn
     * @param y     The y-coordinate of the origin of the text being drawn
     * @param paint The paint used for the text (e.g. color, size, style)
     */
    public void drawText(String text, int start, int end, float x, float y, Paint paint) {
  /*      if ((start | end | (end - start) | (text.length() - end)) < 0) {
            throw new IndexOutOfBoundsException();
        }
        native_drawText(mNativeCanvas, text, start, end, x, y, paint.mBidiFlags,
                paint.mNativePaint);*/
    }

    /**
     * Draw the specified range of text, specified by start/end, with its
     * origin at (x,y), in the specified Paint. The origin is interpreted
     * based on the Align setting in the Paint.
     *
     * @param text     The text to be drawn
     * @param start    The index of the first character in text to draw
     * @param end      (end - 1) is the index of the last character in text
     *                 to draw
     * @param x        The x-coordinate of origin for where to draw the text
     * @param y        The y-coordinate of origin for where to draw the text
     * @param paint The paint used for the text (e.g. color, size, style)
     */
    public void drawText(CharSequence text, int start, int end, float x, float y, Paint paint) {
        /*if (text instanceof String || text instanceof SpannedString ||
            text instanceof SpannableString) {
            native_drawText(mNativeCanvas, text.toString(), start, end, x, y,
                    paint.mBidiFlags, paint.mNativePaint);
        } else if (text instanceof GraphicsOperations) {
            ((GraphicsOperations) text).drawText(this, start, end, x, y,
                    paint);
        } else {
            char[] buf = TemporaryBuffer.obtain(end - start);
            TextUtils.getChars(text, start, end, buf, 0);
            native_drawText(mNativeCanvas, buf, 0, end - start, x, y,
                    paint.mBidiFlags, paint.mNativePaint);
            TemporaryBuffer.recycle(buf);
        }*/
    }
// ---
    /**
     * <p>Draw the specified arc, which will be scaled to fit inside the
     * specified oval.</p>
     * 
     * <p>If the start angle is negative or >= 360, the start angle is treated
     * as start angle modulo 360.</p>
     * 
     * <p>If the sweep angle is >= 360, then the oval is drawn
     * completely. Note that this differs slightly from SkPath::arcTo, which
     * treats the sweep angle modulo 360. If the sweep angle is negative,
     * the sweep angle is treated as sweep angle modulo 360</p>
     * 
     * <p>The arc is drawn clockwise. An angle of 0 degrees correspond to the
     * geometric angle of 0 degrees (3 o'clock on a watch.)</p>
     *
     * @param oval       The bounds of oval used to define the shape and size
     *                   of the arc
     * @param startAngle Starting angle (in degrees) where the arc begins
     * @param sweepAngle Sweep angle (in degrees) measured clockwise
     * @param useCenter If true, include the center of the oval in the arc, and
                        close it if it is being stroked. This will draw a wedge
     * @param paint      The paint used to draw the arc
     */
    public void drawArc(RectF oval, float startAngle, float sweepAngle, boolean useCenter,
            Paint paint) {
        if (oval == null) {
            throw new NullPointerException();
        }
        /*native_drawArc(mNativeCanvas, oval, startAngle, sweepAngle,
                useCenter, paint.mNativePaint);*/
    }
// ---
    /**
     * Preconcat the current matrix with the specified scale.
     *
     * @param sx The amount to scale in X
     * @param sy The amount to scale in Y
     */
    public /*native*/ void scale(float sx, float sy) {}

    /**
     * Preconcat the current matrix with the specified scale.
     *
     * @param sx The amount to scale in X
     * @param sy The amount to scale in Y
     * @param px The x-coord for the pivot point (unchanged by the scale)
     * @param py The y-coord for the pivot point (unchanged by the scale)
     */
    public final void scale(float sx, float sy, float px, float py) {
        /*translate(px, py);
        scale(sx, sy);
        translate(-px, -py);*/
    }
// ---
    /**
     * Draw the specified bitmap, with its top/left corner at (x,y), using
     * the specified paint, transformed by the current matrix.
     * 
     * <p>Note: if the paint contains a maskfilter that generates a mask which
     * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter),
     * then the bitmap will be drawn as if it were in a Shader with CLAMP mode.
     * Thus the color outside of the original width/height will be the edge
     * color replicated.
     *
     * <p>If the bitmap and canvas have different densities, this function
     * will take care of automatically scaling the bitmap to draw at the
     * same density as the canvas.
     * 
     * @param bitmap The bitmap to be drawn
     * @param left   The position of the left side of the bitmap being drawn
     * @param top    The position of the top side of the bitmap being drawn
     * @param paint  The paint used to draw the bitmap (may be null)
     */
	public void drawBitmap(Bitmap bitmap, float left, float top, Paint paint) {/*
		native_drawBitmap(mNativeCanvas, bitmap.ni(), left, top, paint != null ? paint.mNativePaint : 0, mDensity, mScreenDensity, bitmap.mDensity);
	*/}

    /**
     * Draw the specified bitmap, scaling/translating automatically to fill
     * the destination rectangle. If the source rectangle is not null, it
     * specifies the subset of the bitmap to draw.
     * 
     * <p>Note: if the paint contains a maskfilter that generates a mask which
     * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter),
     * then the bitmap will be drawn as if it were in a Shader with CLAMP mode.
     * Thus the color outside of the original width/height will be the edge
     * color replicated.
     *
     * <p>This function <em>ignores the density associated with the bitmap</em>.
     * This is because the source and destination rectangle coordinate
     * spaces are in their respective densities, so must already have the
     * appropriate scaling factor applied.
     * 
     * @param bitmap The bitmap to be drawn
     * @param src    May be null. The subset of the bitmap to be drawn
     * @param dst    The rectangle that the bitmap will be scaled/translated
     *               to fit into
     * @param paint  May be null. The paint used to draw the bitmap
     */
	public void drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint) {
		if (dst == null) {
			throw new NullPointerException();
		}
		native_drawBitmap(cairo_context, widget, bitmap.pixbuf, src.left, src.top, dst.left, dst.top, paint); // FIXME - ignores width/height
	}

    /**
     * Draw the specified bitmap, scaling/translating automatically to fill
     * the destination rectangle. If the source rectangle is not null, it
     * specifies the subset of the bitmap to draw.
     * 
     * <p>Note: if the paint contains a maskfilter that generates a mask which
     * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter),
     * then the bitmap will be drawn as if it were in a Shader with CLAMP mode.
     * Thus the color outside of the original width/height will be the edge
     * color replicated.
     *
     * <p>This function <em>ignores the density associated with the bitmap</em>.
     * This is because the source and destination rectangle coordinate
     * spaces are in their respective densities, so must already have the
     * appropriate scaling factor applied.
     * 
     * @param bitmap The bitmap to be drawn
     * @param src    May be null. The subset of the bitmap to be drawn
     * @param dst    The rectangle that the bitmap will be scaled/translated
     *               to fit into
     * @param paint  May be null. The paint used to draw the bitmap
     */
    public void drawBitmap(Bitmap bitmap, Rect src, Rect dst, Paint paint) {/*
		if (dst == null) {
			throw new NullPointerException();
		}
		native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, paint != null ? paint.mNativePaint : 0, mScreenDensity, bitmap.mDensity);
	*/}
    
    /**
     * Treat the specified array of colors as a bitmap, and draw it. This gives
     * the same result as first creating a bitmap from the array, and then
     * drawing it, but this method avoids explicitly creating a bitmap object
     * which can be more efficient if the colors are changing often.
     *
     * @param colors Array of colors representing the pixels of the bitmap
     * @param offset Offset into the array of colors for the first pixel
     * @param stride The number of colors in the array between rows (must be
     *               >= width or <= -width).
     * @param x The X coordinate for where to draw the bitmap
     * @param y The Y coordinate for where to draw the bitmap
     * @param width The width of the bitmap
     * @param height The height of the bitmap
     * @param hasAlpha True if the alpha channel of the colors contains valid
     *                 values. If false, the alpha byte is ignored (assumed to
     *                 be 0xFF for every pixel).
     * @param paint  May be null. The paint used to draw the bitmap
     */
    public void drawBitmap(int[] colors, int offset, int stride, float x, float y,
            int width, int height, boolean hasAlpha, Paint paint) {
/*        // check for valid input
        if (width < 0) {
            throw new IllegalArgumentException("width must be >= 0");
        }
        if (height < 0) {
            throw new IllegalArgumentException("height must be >= 0");
        }
        if (Math.abs(stride) < width) {
            throw new IllegalArgumentException("abs(stride) must be >= width");
        }
        int lastScanline = offset + (height - 1) * stride;
        int length = colors.length;
        if (offset < 0 || (offset + width > length) || lastScanline < 0
                || (lastScanline + width > length)) {
            throw new ArrayIndexOutOfBoundsException();
        }
        // quick escape if there's nothing to draw
        if (width == 0 || height == 0) {
            return;
        }
        // punch down to native for the actual draw
        native_drawBitmap(mNativeCanvas, colors, offset, stride, x, y, width, height, hasAlpha,
                paint != null ? paint.mNativePaint : 0);*/
    }
    
    /** Legacy version of drawBitmap(int[] colors, ...) that took ints for x,y
     */
    public void drawBitmap(int[] colors, int offset, int stride, int x, int y,
            int width, int height, boolean hasAlpha, Paint paint) {
        // call through to the common float version
        drawBitmap(colors, offset, stride, (float)x, (float)y, width, height,
                   hasAlpha, paint);
    }
        
    /**
     * Draw the bitmap using the specified matrix.
     *
     * @param bitmap The bitmap to draw
     * @param matrix The matrix used to transform the bitmap when it is drawn
     * @param paint  May be null. The paint used to draw the bitmap
     */
    public void drawBitmap(Bitmap bitmap, Matrix matrix, Paint paint) {
 /*       nativeDrawBitmapMatrix(mNativeCanvas, bitmap.ni(), matrix.ni(),
                paint != null ? paint.mNativePaint : 0);*/
    }
// ---
    /**
     * Draw a line segment with the specified start and stop x,y coordinates,
     * using the specified paint.
     *
     * <p>Note that since a line is always "framed", the Style is ignored in the paint.</p>
     *
     * <p>Degenerate lines (length is 0) will not be drawn.</p>
     *
     * @param startX The x-coordinate of the start point of the line
     * @param startY The y-coordinate of the start point of the line
     * @param paint  The paint used to draw the line
     */
	public void drawLine(float startX, float startY, float stopX, float stopY, Paint paint) {
		native_drawLine(cairo_context, widget, startX, startY, stopX, stopY, paint.getColor());
	}

	private static native void native_drawLine(long cairo_context, long widget, float startX, float startY, float stopX, float stopY, int paint_color); // TODO: pass all the other relevant parameters extracted from paint
	private static native void native_drawBitmap(long cairo_context, long widget, long pixbuf, float src_x, float src_y, float dest_x, float dest_y, Paint paint); // TODO: make use of "paint"?
	private static native void native_rotate(long cairo_context, long widget, float angle);
	private static native void native_rotate_and_translate(long cairo_context, long widget, float angle, float tx, float ty);
}