/**

 * Back 2 Browser Bytecode Translator Copyright (C) 2012 Jaroslav Tulach

 * <jaroslav.tulach@apidesign.org>

 *

 * This program is free software: you can redistribute it and/or modify it under

 * the terms of the GNU General Public License as published by the Free Software

 * Foundation, version 2 of the License.

 *

 * This program is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS

 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more

 * details.

 *

 * You should have received a copy of the GNU General Public License along with

 * this program. Look for COPYING file in the top folder. If not, see

 * http://opensource.org/licenses/GPL-2.0.

 */

package net.java.html.canvas.spi;

import net.java.html.canvas.Dimension;

import net.java.html.canvas.Image;

import net.java.html.canvas.ImageData;

import net.java.html.canvas.Style;

/**

 * Provider API for Canvas. Implement this to add support for your platform.

 *

 * @author antonepple

 */

public interface GraphicsEnvironment {

    /**

     * Adds path elements to the current path to make an arc.

     *

     * @param centerX the center x position of the arc.

     * @param centerY the center y position of the arc.

     * @param startAngle the startAngle of the arc

     * @param radius the radius of the arc.

     * @param endAngle the endAngle of the arc

     * @param ccw the direction of the arc (counterclockwise)

     */

    public void arc(double centerX,

            double centerY,

            double startAngle,

            double radius,

            double endAngle,

            boolean ccw);

    /**

     * Adds segments to the current path to make an arc.

     *

     * @param x1 the X coordinate of the first point of the arc.

     * @param y1 the Y coordinate of the first point of the arc.

     * @param x2 the X coordinate of the second point of the arc.

     * @param y2 the Y coordinate of the second point of the arc.

     * @param radius the radius of the arc in the range {0.0-positive infinity}.

     */

    public void arcTo(double x1,

            double y1,

            double x2,

            double y2,

            double radius);

    /**

     * Returns true if the the given x,y point is inside the path.

     *

     * @param x the X coordinate to use for the check.

     * @param y the Y coordinate to use for the check.

     * @return true if the point given is inside the path, false otherwise.

     */

    public boolean isPointInPath(double x, double y);

    /**

     * Fills the path with the current fill paint.

     */

    public void fill();

    /**

     * Strokes the path with the current stroke paint.

     */

    public void stroke();

    /**

     * Starts a Path

     */

    public void beginPath();

    /**

     * Closes the path.

     */

    public void closePath();

    /**

     * Clips using the current path

     */

    public void clip();

    /**

     * Issues a move command for the current path to the given x,y coordinate.

     *

     * @param x the X position for the move to command.

     * @param y the Y position for the move to command.

     */

    public void moveTo(double x, double y);

    /**

     * Adds segments to the current path to make a line at the given x,y

     * coordinate.

     *

     * @param x the X coordinate of the ending point of the line.

     * @param y the Y coordinate of the ending point of the line.

     */

    public void lineTo(double x, double y);

    /**

     * Adds segments to the current path to make a quadratic curve.

     *

     * @param cpx the X coordinate of the control point

     * @param cpy the Y coordinate of the control point

     * @param x the X coordinate of the end point

     * @param y the Y coordinate of the end point

     */

    public void quadraticCurveTo(double cpx, double cpy, double x, double y);

    /**

     * Adds segments to the current path to make a cubic bezier curve.

     *

     * @param cp1x the X coordinate of first bezier control point.

     * @param cp1y the Y coordinate of the first bezier control point.

     * @param cp2x the X coordinate of the second bezier control point.

     * @param cp2y the Y coordinate of the second bezier control point.

     * @param x the X coordinate of the end point.

     * @param y the Y coordinate of the end point.

     */

    public void bezierCurveTo(double cp1x, double cp1y, double cp2x, double cp2y, double x, double y);

    /**

     * Fills a rectangle using the current fill paint.

     *

     * @param x the X position of the upper left corner of the rectangle.

     * @param y the Y position of the upper left corner of the rectangle.

     * @param width the width of the rectangle.

     * @param height the height of the rectangle.

     */

    public void fillRect(double x, double y, double width, double height);

    /**

     * Strokes a rectangle using the current stroke paint.

     *

     * @param x the X position of the upper left corner of the rectangle.

     * @param y the Y position of the upper left corner of the rectangle.

     * @param width the width of the rectangle.

     * @param height the height of the rectangle.

     */

    public void strokeRect(double x, double y, double width, double height);

    /**

     * Clears a portion of the canvas with a transparent color value.

     *

     * @param x X position of the upper left corner of the rectangle.

     * @param y Y position of the upper left corner of the rectangle.

     * @param width width of the rectangle.

     * @param height height of the rectangle.

     */

    public void clearRect(double x, double y, double width, double height);

    /**

     * Clears a portion of the canvas with a transparent color value.

     *

     * @param x X position of the upper left corner of the rectangle.

     * @param y Y position of the upper left corner of the rectangle.

     * @param width width of the rectangle.

     * @param height height of the rectangle.

     */

    public void rect(double x, double y, double width, double height);

    /**

     * Saves the following attributes onto a stack.

     * <ul>

     * <li>Global Alpha</li>

     * <li>Global Blend Operation</li>

     * <li>Transform</li>

     * <li>Fill Paint</li>

     * <li>Stroke Paint</li>

     * <li>Line Width</li>

     * <li>Line Cap</li>

     * <li>Line Join</li>

     * <li>Miter Limit</li>

     * <li>Number of Clip Paths</li>

     * <li>Font</li>

     * <li>Text Align</li>

     * <li>Text Baseline</li>

     * <li>Effect</li>

     * <li>Fill Rule</li>

     * </ul>

     * This method does NOT alter the current state in any way. Also, not that

     * the current path is not saved.

     */

    public void save();

    /**

     * Pops the state off of the stack, setting the following attributes to

     * their value at the time when that state was pushed onto the stack. If the

     * stack is empty then nothing is changed.

     *

     * <ul>

     * <li>Global Alpha</li>

     * <li>Global Blend Operation</li>

     * <li>Transform</li>

     * <li>Fill Paint</li>

     * <li>Stroke Paint</li>

     * <li>Line Width</li>

     * <li>Line Cap</li>

     * <li>Line Join</li>

     * <li>Miter Limit</li>

     * <li>Number of Clip Paths</li>

     * <li>Font</li>

     * <li>Text Align</li>

     * <li>Text Baseline</li>

     * <li>Effect</li>

     * <li>Fill Rule</li>

     * </ul>

     */

    public void restore();

    /**

     * Rotates the current transform in degrees.

     *

     * @param angle value in degrees to rotate the current transform.

     */

    public void rotate(double angle);

    /**

     * Concatenates the input with the current transform.

     *

     * @param a - the X coordinate scaling element of the 3x4 matrix

     * @param b - the Y coordinate shearing element of the 3x4 matrix

     * @param c - the X coordinate shearing element of the 3x4 matrix

     * @param d - the Y coordinate scaling element of the 3x4 matrix

     * @param e - the X coordinate translation element of the 3x4 matrix

     * @param f - the Y coordinate translation element of the 3x4 matrix

     */

    public void transform(double a, double b, double c, double d, double e, double f);

    /**

     * Concatenates the input with the current transform.

     *

     * @param a - the X coordinate scaling element of the 3x4 matrix

     * @param b - the Y coordinate shearing element of the 3x4 matrix

     * @param c - the X coordinate shearing element of the 3x4 matrix

     * @param d - the Y coordinate scaling element of the 3x4 matrix

     * @param e - the X coordinate translation element of the 3x4 matrix

     * @param f - the Y coordinate translation element of the 3x4 matrix

     */

    public void setTransform(double a, double b, double c, double d, double e, double f);

    /**

     * Translates the current transform by x, y.

     *

     * @param x value to translate along the x axis.

     * @param y value to translate along the y axis.

     */

    public void translate(double x, double y);

    /**

     * Scales the current transform by x, y.

     *

     * @param x value to scale in the x axis.

     * @param y value to scale in the y axis.

     */

    public void scale(double x, double y);

    /**

     * Draws an image at the given x, y position using the width and height of

     * the given image.

     *

     * @param image the image to be drawn.

     * @param x the X coordinate on the destination for the upper left of the

     * image.

     * @param y the Y coordinate on the destination for the upper left of the

     * image.

     * @return the native Image for caching.

     */

    public Object drawImage(Image image, double x, double y, Object nativeImage);

    /**

     * Draws an image into the given destination rectangle of the canvas. The

     * Image is scaled to fit into the destination rectagnle.

     *

     * @param image the image to be drawn.

     * @param x the X coordinate on the destination for the upper left of the

     * image.

     * @param y the Y coordinate on the destination for the upper left of the

     * image.

     * @param width the width of the destination rectangle.

     * @param height the height of the destination rectangle.

     * @return the native Image for caching.

     *

     */

    public Object drawImage(Image image, double x, double y, double width, double height, Object nativeImage);

    /**

     * Draws the current source rectangle of the given image to the given

     * destination rectangle of the Canvas.

     *

     * @param image the image to be drawn.

     * @param sx the source rectangle's X coordinate position.

     * @param sy the source rectangle's Y coordinate position.

     * @param sWidth the source rectangle's width.

     * @param sHeight the source rectangle's height.

     * @param x the destination rectangle's X coordinate position.

     * @param y the destination rectangle's Y coordinate position.

     * @param width the destination rectangle's width.

     * @param height the destination rectangle's height.

     * @return the native Image for caching.

     */

    public Object drawImage(Image image, double sx, double sy, double sWidth, double sHeight, double x, double y, double width, double height, Object nativeImage);

    /**

     * Get the width of this Image

     *

     * @param image the image to measure

     * @param nativeImage the cached native Image or null

     * @return the width of the image

     */

    public int getWidth(Image image, Object nativeImage);

    /**

     * Get the height of this Image

     *

     * @param image the image to measure

     * @param nativeImage the cached native Image or null

     * @return the height of the image

     */

    public int getHeight(Image image, Object nativeImage);

    /**

     * When implementing you can return an Object of your choice to enable

     * caching. Returning null means no caching. When caching is enabled, and

     * the cache hasn't been invalidated, the Object you returned will be passed

     * as a parameter.

     *

     * @param style The style object you should use to create your native style

     * @param nativeStyle your native object if cached, null otherwise

     * @return return native Object for caching

     *

     */

    public Object setFillStyle(Style style, Object nativeStyle);

    /**

     * When implementing you can return an Object of your choice to enable

     * caching. Returning null means no caching. When caching is enabled, and

     * the cache hasn't been invalidated, the Object you returned will be passed

     * as a parameter.

     *

     * @param style The style object you should use to create your native style

     * @param nativeStyle your native object if cached, null otherwise

     * @return return native Object for caching

     *

     */

    public Object setStrokeStyle(Style style, Object nativeStyle);

//    public void setShadowColor(String color);

//

//    public void setShadowBlur(double blur);

//

//    public void setShadowOffsetX(double x);

//

//    public void setShadowOffsetY(double y);

//    

//    public String getShadowColor();

//

//    public double getShadowBlur();

//

//    public double getShadowOffsetX();

//

//    public double getShadowOffsetY();

    /**

     * Gets the current stroke line cap.

     *

     * @return {@code StrokeLineCap} with a value of Butt, Round, or Square.

     */

    public String getLineCap();

    /**

     * Sets the current stroke line cap.

     *

     * @param style a value of Butt, Round, or Square.

     */

    public void setLineCap(String style);

    /**

     * Gets the current stroke line join.

     *

     * @return a value of Miter, Bevel, or Round.

     */

    public String getLineJoin();

    /**

     * Sets the current stroke line join.

     *

     * @param style with a value of Miter, Bevel, or Round.

     */

    public void setLineJoin(String style);

    /**

     * Gets the current line width.

     *

     * @return value between 0 and infinity.

     */

    public double getLineWidth();

    /**

     * Sets the current line width.

     *

     * @param width value in the range {0-positive infinity}, with any other

     * value being ignored and leaving the value unchanged.

     */

    public void setLineWidth(double width);

    /**

     * Gets the current miter limit. v

     *

     * @return the miter limit value in the range {@code 0.0-positive infinity}

     */

    public double getMiterLimit();

    /**

     * Sets the current miter limit.

     *

     * @param limit miter limit value between 0 and positive infinity with any

     * other value being ignored and leaving the value unchanged.

     */

    public void setMiterLimit(double limit);

    /**

     * Gets the current Font.

     *

     * @return the Font

     */

    public String getFont();

    /**

     * Sets the current Font.

     *

     */

    public void setFont(String font);

    /**

     * Gets the current {@code TextAlignment}.

     *

     * @return TextAlignment with values of Left, Center, Right, or Justify.

     */

    public String getTextAlign();

    /**

     * Defines horizontal text alignment, relative to the text origin.

     *

     * @param textAlign with values of Left, Center, Right.

     */

    public void setTextAlign(String textAlign);

    /**

     * Sets the current Text Baseline.

     *

     * @param baseline with values of Top, Center, Baseline, or Bottom

     */

    public String getTextBaseline();

    /**

     * Sets the current Text Baseline.

     *

     * @param baseline with values of Top, Center, Baseline, or Bottom

     */

    public void setTextBaseline(String baseline);

    /**

     * Fills the given string of text at position x, y (0,0 at top left) with

     * the current fill paint attribute.

     *

     * @param text the string of text.

     * @param x position on the x axis.

     * @param y position on the y axis.

     */

    public void fillText(String text, double x, double y);

    /**

     * Fills text and includes a maximum width of the string.

     *

     * If the width of the text extends past max width, then it will be sized to

     * fit.

     *

     * @param text the string of text.

     * @param x position on the x axis.

     * @param y position on the y axis.

     * @param maxWidth maximum width the text string can have.

     */

    public void fillText(String text, double x, double y, double maxWidth);

    /**

     * The Dimension of this text using the current Font settings

     *

     * @param text

     * @return the Dimension of this text using the current Font settings

     */

    public Dimension measureText(String text);

    /**

     * draws the given string of text at position x, y (0,0 at top left) with

     * the current stroke paint attribute.

     *

     * @param text the string of text.

     * @param x position on the x axis.

     * @param y position on the y axis.

     */

    public void strokeText(String text, double x, double y);

    /**

     * Draws text with stroke paint and includes a maximum width of the string.

     *

     * If the width of the text extends past max width, then it will be sized to

     * fit.

     *

     * @param text the string of text.

     * @param x position on the x axis.

     * @param y position on the y axis.

     * @param maxWidth maximum width the text string can have.

     */

    public void strokeText(String text, double x, double y, double maxWidth);

    /**

     * Get a pixel array that you can manipulate, e.g. apply effects / transparency

     * @param x width

     * @param y height

     * @return a PixelMap

     */

    public ImageData createPixelMap(double x, double y);

    /**

     * Create a new ImageData object with the same dimensions as the 

     * object specified by imageData (this does not copy the image data)

     * @param imageData

     * @return 

     */

    public ImageData createPixelMap(ImageData imageData);

    /**

     * Get the pixels for a region of your GraphicsContext

     * @param x start x coordinate

     * @param y start y coordinate

     * @param width width

     * @param height height

     * @return 

     */

    public ImageData getPixelMap(double x, double y, double width, double height);

    /**

     * Render an ImageData Object at the specified position

     * @param imageData the Pixel array

      * @param x start x coordinate

     * @param y start y coordinate

     */

   public void putPixelMap(ImageData imageData, double x, double y);

    /**

     * Render an ImageData Object at the specified position

     * @param imageData the Pixel array to draw

     * @param x start x coordinate

     * @param y start y coordinate

     * @param dirtyx The horizontal (x) value, in pixels, where to place the image on the canvas

     * @param dirtyy The vertical (y) value, in pixels, where to place the image on the canvas

     * @param dirtywidth The width to use to draw the image on the canvas

     * @param dirtyheight The height to use to draw the image on the canvas

     */

    public void putPixelMap(ImageData imageData, double x, double y, double dirtyx, double dirtyy, double dirtywidth, double dirtyheight);

    /**

     * Sets the global alpha of the current state.

     *

     * @param alpha value in the range {@code 0.0-1.0}. The value is clamped if

     * it is out of range.

     */

    public void setGlobalAlpha(double alpha);

    /**

     * Get the global alpha of the current state.

     *

     * @return alpha value in the range {@code 0.0-1.0}.

     */

    public double getGlobalAlpha();

    /**

     * Sets the global blend mode.

     *

     * @param operation the BlendMode that will be set.

     */

    public void setGlobalCompositeOperation(String operation);

    /**

     * Gets the global blend mode.

     *

     * @return the global BlendMode of the current state.

     */

    public String getGlobalCompositeOperation();

    /**

     * Get the height of this GraphicsContext (which should be the same as the

     * enclosing canvas height)

     *

     * @return the height of this GraphicsContext

     */

    public int getHeight();

    /**

     * Get the width of this GraphicsContext (which should be the same as the

     * enclosing canvas height)

     *

     * @return the width of this GraphicsContext

     */

    public int getWidth();

//    public void setHeight(int height);

//

//    public void setWidth(int width);

     /**

     * Merges two images drawing one on top of the other and returning the

     * result.

     *

     * @param a the lower Image

     * @param b the upper Image

     * @param cachedA the native cached Image, if available, or null.

     * @param cachedB the native cached Image, if available, or null.

     * @return

     */  

    public Object mergeImages(Image a, Image b, Object cachedA, Object cachedB);

}