/*

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */
package org.apache.batik.bridge;

import java.awt.Cursor;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.geom.AffineTransform;
import java.awt.geom.Dimension2D;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

import org.apache.batik.gvt.event.EventDispatcher;
import org.apache.batik.util.ParsedURL;
import org.apache.batik.util.SVGFeatureStrings;
import org.apache.batik.util.XMLResourceDescriptor;

import org.w3c.dom.Element;
import org.w3c.dom.svg.SVGAElement;
import org.w3c.dom.svg.SVGDocument;

An abstract user agent adaptor implementation.  It exists to simply
the creation of UserAgent instances.
Author:
Thomas DeWeese
Version:
$Id: UserAgentAdapter.java 1805408 2017-08-18 12:21:52Z ssteiner $/**
 * An abstract user agent adaptor implementation.  It exists to simply
 * the creation of UserAgent instances.
 *
 * @author <a href="mailto:thomas.deweese@kodak.com">Thomas DeWeese</a>
 * @version $Id: UserAgentAdapter.java 1805408 2017-08-18 12:21:52Z ssteiner $
 */
public class UserAgentAdapter implements UserAgent {
    protected Set FEATURES   = new HashSet();
    protected Set extensions = new HashSet();

    
The BridgeContext to use for error information.
/**
     * The BridgeContext to use for error information.
     */
    protected BridgeContext ctx;

    
Sets the BridgeContext to be used for error information.
/**
     * Sets the BridgeContext to be used for error information.
     */
    public void setBridgeContext(BridgeContext ctx) {
        this.ctx = ctx;
    }

    
Adds the standard SVG feature strings to the set of features supported
by this user agent.
/**
     * Adds the standard SVG feature strings to the set of features supported
     * by this user agent.
     */
    public void addStdFeatures() {
        SVGFeatureStrings.addSupportedFeatureStrings(FEATURES);
    }

    
Returns the default size of this user agent (400x400).
/**
     * Returns the default size of this user agent (400x400).
     */
    public Dimension2D getViewportSize() {
        return new Dimension(1, 1);
    }

    
Display the specified message.
/**
     * Display the specified message.
     */
    public void displayMessage(String message) {
    }

    
Display the specified error message (forwards call to displayMessage).
/**
     * Display the specified error message (forwards call to displayMessage).
     */
    public void displayError(String message) {
        displayMessage(message);
    }

    
Display the specified error (forwards call to displayError(String))
/**
     * Display the specified error (forwards call to displayError(String))
     */
    public void displayError(Exception e) {
        displayError(e.getMessage());
    }

    
Shows an alert dialog box.
/**
     * Shows an alert dialog box.
     */
    public void showAlert(String message) {
    }

    
Shows a prompt dialog box.
/**
     * Shows a prompt dialog box.
     */
    public String showPrompt(String message) {
        return null;
    }

    
Shows a prompt dialog box.
/**
     * Shows a prompt dialog box.
     */
    public String showPrompt(String message, String defaultValue) {
        return null;
    }

    
Shows a confirm dialog box.
/**
     * Shows a confirm dialog box.
     */
    public boolean showConfirm(String message) {
        return false;
    }

    
Returns the size of a px CSS unit in millimeters.
/**
     * Returns the size of a px CSS unit in millimeters.
     */
    public float getPixelUnitToMillimeter() {
        return 0.26458333333333333333333333333333f; // 96dpi
    }

    
Returns the size of a px CSS unit in millimeters.
This will be removed after next release.
See Also:
getPixelUnitToMillimeter()/**
     * Returns the size of a px CSS unit in millimeters.
     * This will be removed after next release.
     * @see #getPixelUnitToMillimeter()
     */
    public float getPixelToMM() {
        return getPixelUnitToMillimeter();
            
    }

    
Returns the default font family.
/**
     * Returns the default font family.
     */
    public String getDefaultFontFamily() {
        return "Arial, Helvetica, sans-serif";
    }

    
Returns the  medium font size. 
/** 
     * Returns the  medium font size. 
     */
    public float getMediumFontSize() {
        // 9pt (72pt = 1in)
        return 9f * 25.4f / (72f * getPixelUnitToMillimeter());
    }

    
Returns a lighter font-weight.
/**
     * Returns a lighter font-weight.
     */
    public float getLighterFontWeight(float f) { 
        return getStandardLighterFontWeight(f);
    }

    
Returns a bolder font-weight.
/**
     * Returns a bolder font-weight.
     */
    public float getBolderFontWeight(float f) {
        return getStandardBolderFontWeight(f);
    }


    
Returns the user language "en" (english).
/**
     * Returns the user language "en" (english).
     */
    public String getLanguages() {
        return "en";
    }

    
Returns this user agent's CSS media.
/**
     * Returns this user agent's CSS media.
     */
    public String getMedia() {
        return "all";
    }

    
Returns this user agent's alternate style-sheet title.
/**
     * Returns this user agent's alternate style-sheet title.
     */
    public String getAlternateStyleSheet() {
        return null;
    }

    
Returns the user stylesheet 
/**
     * Returns the user stylesheet 
     */
    public String getUserStyleSheetURI() {
        return null;
    }

    
Returns the XML parser to use
/**
     * Returns the XML parser to use
     */
    public String getXMLParserClassName() {
        return XMLResourceDescriptor.getXMLParserClassName();
    }

    
Returns false. The XML parser is not in validation mode.
/**
     * Returns <code>false</code>. The XML parser is not in validation mode.
     */
    public boolean isXMLParserValidating() {
        return false;
    }

    
Unsupported operation.
/**
     * Unsupported operation.
     */
    public EventDispatcher getEventDispatcher() {
        return null;
    }

    
Unsupported operation.
/**
     * Unsupported operation.
     */
    public void openLink(SVGAElement elt) { }

    
Unsupported operation.
/**
     * Unsupported operation.
     */
    public void setSVGCursor(Cursor cursor) { }

    
This user agent doesn't display text selections.
/**
     * This user agent doesn't display text selections.
     */
    public void setTextSelection(Mark start, Mark end) { }

    
This user agent doesn't display text selections so nothing to clear.
/**
     * This user agent doesn't display text selections so nothing to clear.
     */
    public void deselectAll() { }

    
Unsupported operation.
/**
     * Unsupported operation.
     */
    public void runThread(Thread t) { }

    
Unsupported operation.
/**
     * Unsupported operation.
     */
    public AffineTransform getTransform() {
        return null;
    }

    
Unsupported operation.
/**
     * Unsupported operation.
     */
    public void setTransform(AffineTransform at) {
        // Do nothing.
    }

    
Unsupported operation.
/**
     * Unsupported operation.
     */
    public Point getClientAreaLocationOnScreen() {
        return new Point();
    }

    
Tells whether the given feature is supported by this
user agent.
/**
     * Tells whether the given feature is supported by this
     * user agent.
     */
    public boolean hasFeature(String s) {
        return FEATURES.contains(s);
    }

    
Tells whether the given extension is supported by this
user agent.
/**
     * Tells whether the given extension is supported by this
     * user agent.
     */
    public boolean supportExtension(String s) {
        return extensions.contains(s);
    }

    
Lets the bridge tell the user agent that the following
ex   tension is supported by the bridge.  
/**
     * Lets the bridge tell the user agent that the following
     * ex   tension is supported by the bridge.  
     */
    public void registerExtension(BridgeExtension ext) {
        Iterator i = ext.getImplementedExtensions();
        while (i.hasNext())
            extensions.add(i.next());
    }


    
Notifies the UserAgent that the input element 
has been found in the document. This is sometimes
called, for example, to handle <a> or
<title> elements in a UserAgent-dependant
way.
/**
     * Notifies the UserAgent that the input element 
     * has been found in the document. This is sometimes
     * called, for example, to handle &lt;a&gt; or
     * &lt;title&gt; elements in a UserAgent-dependant
     * way.
     */
    public void handleElement(Element elt, Object data){
    }

    
Returns the security settings for the given script
type, script url and document url
Params:
scriptType – type of script, as found in the 
       type attribute of the <script> element.
scriptURL – url for the script, as defined in
       the script's xlink:href attribute. If that
       attribute was empty, then this parameter should
       be null
docURL – url for the document into which the 
       script was found./**
     * Returns the security settings for the given script
     * type, script url and document url
     * 
     * @param scriptType type of script, as found in the 
     *        type attribute of the &lt;script&gt; element.
     * @param scriptURL url for the script, as defined in
     *        the script's xlink:href attribute. If that
     *        attribute was empty, then this parameter should
     *        be null
     * @param docURL url for the document into which the 
     *        script was found.
     */
    public ScriptSecurity getScriptSecurity(String    scriptType,
                                            ParsedURL scriptURL,
                                            ParsedURL docURL){
        return new DefaultScriptSecurity(scriptType, scriptURL, docURL);
    }
    
    
This method throws a SecurityException if the script
of given type, found at url and referenced from docURL
should not be loaded.
This is a convenience method to call checkLoadScript
on the ScriptSecurity strategy returned by 
getScriptSecurity.
Params:
scriptType – type of script, as found in the 
       type attribute of the <script> element.
scriptURL – url for the script, as defined in
       the script's xlink:href attribute. If that
       attribute was empty, then this parameter should
       be null
docURL – url for the document into which the 
       script was found./**
     * This method throws a SecurityException if the script
     * of given type, found at url and referenced from docURL
     * should not be loaded.
     * 
     * This is a convenience method to call checkLoadScript
     * on the ScriptSecurity strategy returned by 
     * getScriptSecurity.
     *
     * @param scriptType type of script, as found in the 
     *        type attribute of the &lt;script&gt; element.
     * @param scriptURL url for the script, as defined in
     *        the script's xlink:href attribute. If that
     *        attribute was empty, then this parameter should
     *        be null
     * @param docURL url for the document into which the 
     *        script was found.
     */
    public void checkLoadScript(String scriptType,
                                ParsedURL scriptURL,
                                ParsedURL docURL) throws SecurityException {
        ScriptSecurity s = getScriptSecurity(scriptType,
                                             scriptURL,
                                             docURL);
        if (s != null) {
            s.checkLoadScript();
        }
    }

    
Returns the security settings for the given resource
url and document url
Params:
resourceURL – url for the resource, as defined in
       the resource's xlink:href attribute. If that
       attribute was empty, then this parameter should
       be null
docURL – url for the document into which the 
       resource was found./**
     * Returns the security settings for the given resource
     * url and document url
     * 
     * @param resourceURL url for the resource, as defined in
     *        the resource's xlink:href attribute. If that
     *        attribute was empty, then this parameter should
     *        be null
     * @param docURL url for the document into which the 
     *        resource was found.
     */
    public ExternalResourceSecurity 
        getExternalResourceSecurity(ParsedURL resourceURL,
                                    ParsedURL docURL) {
        return new RelaxedExternalResourceSecurity(resourceURL, docURL);
    }
    
    
This method throws a SecurityException if the resource
found at url and referenced from docURL
should not be loaded.
This is a convenience method to call checkLoadExternalResource
on the ExternalResourceSecurity strategy returned by 
getExternalResourceSecurity.
Params:
resourceURL – url for the resource, as defined in
       the resource's xlink:href attribute. If that
       attribute was empty, then this parameter should
       be null
docURL – url for the document into which the 
       resource was found./**
     * This method throws a SecurityException if the resource
     * found at url and referenced from docURL
     * should not be loaded.
     * 
     * This is a convenience method to call checkLoadExternalResource
     * on the ExternalResourceSecurity strategy returned by 
     * getExternalResourceSecurity.
     *
     * @param resourceURL url for the resource, as defined in
     *        the resource's xlink:href attribute. If that
     *        attribute was empty, then this parameter should
     *        be null
     * @param docURL url for the document into which the 
     *        resource was found.
     */
    public void 
        checkLoadExternalResource(ParsedURL resourceURL,
                                  ParsedURL docURL) throws SecurityException {
        ExternalResourceSecurity s 
            =  getExternalResourceSecurity(resourceURL, docURL);

        if (s != null) {
            s.checkLoadExternalResource();
        }
    }

    
Returns a lighter font-weight.
/**
     * Returns a lighter font-weight.
     */
    public static float getStandardLighterFontWeight(float f) {
        // Round f to nearest 100...
        int weight = ((int)((f+50)/100))*100;
        switch (weight) {
        case 100: return 100;
        case 200: return 100;
        case 300: return 200;
        case 400: return 300;
        case 500: return 400;
        case 600: return 400;
        case 700: return 400;
        case 800: return 400;
        case 900: return 400;
        default:
            throw new IllegalArgumentException("Bad Font Weight: " + f);
        }
    }

    
Returns a bolder font-weight.
/**
     * Returns a bolder font-weight.
     */
    public static float getStandardBolderFontWeight(float f) {
        // Round f to nearest 100...
        int weight = ((int)((f+50)/100))*100;
        switch (weight) {
        case 100: return 600;
        case 200: return 600;
        case 300: return 600;
        case 400: return 600;
        case 500: return 600;
        case 600: return 700;
        case 700: return 800;
        case 800: return 900;
        case 900: return 900;
        default:
            throw new IllegalArgumentException("Bad Font Weight: " + f);
        }
    }

    
This Implementation simply throws a BridgeException.
Params:
e –   The <image> element that can't be loaded.
url – The resolved url that can't be loaded.
message – As best as can be determined the reason it can't be
               loaded (not available, corrupt, unknown format,...)./**
     * This Implementation simply throws a BridgeException.
     *
     * @param e   The &lt;image&gt; element that can't be loaded.
     * @param url The resolved url that can't be loaded.
     * @param message As best as can be determined the reason it can't be
     *                loaded (not available, corrupt, unknown format,...).
     */
    public SVGDocument getBrokenLinkDocument(Element e, 
                                             String url, 
                                             String message) {
        throw new BridgeException(ctx, e, ErrorConstants.ERR_URI_IMAGE_BROKEN,
                                  new Object[] {url, message });
    }

    
This method should load a new document described by the supplied URL.
Params:
url – The url to be loaded as a string./**
     * This method should load a new document described by the supplied URL.
     *
     * @param url The url to be loaded as a string.
     */
    public void loadDocument(String url) {
        // Do nothing.
    }

    
Returns the Font Family Resolver
/**
     * Returns the Font Family Resolver
     */
    public FontFamilyResolver getFontFamilyResolver() {
        return DefaultFontFamilyResolver.SINGLETON;
    }
}