/*

   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.test.svg;

import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

import org.apache.batik.anim.dom.SAXSVGDocumentFactory;
import org.apache.batik.bridge.BaseScriptingEnvironment;
import org.apache.batik.bridge.BridgeContext;
import org.apache.batik.bridge.BridgeException;
import org.apache.batik.bridge.GVTBuilder;
import org.apache.batik.bridge.UserAgent;
import org.apache.batik.bridge.UserAgentAdapter;
import org.apache.batik.test.AbstractTest;
import org.apache.batik.test.DefaultTestReport;
import org.apache.batik.test.TestReport;
import org.apache.batik.util.XMLResourceDescriptor;

/**
 * This test takes an SVG file as an input. It processes the input SVG
 * (meaning it turns it into a GVT tree) and then dispatches the 'onload'
 * event.
 * 
 * The SVG input file should contain script that will position the 
 * result of the test in the DOM using the following namespace: <br>
 * xmlns:test="http://xml.apache.org/batik/test" <br>
 * 
 * The result should be set in the <code>result</code> attribute of the
 * &lt;testResult&gt; element by the script embeded in the input SVG
 * test file. <br>
 * 
 * Sample input SVG file:<br><code>
 * &lt;svg ... onload="runTest(evt)" xmlns:test="http://xml.apache.org/batik/test" &gt;
 *   &lt;script type="text/ecmascript"&gt;
 *   function runTest(evt) {
 *      ...; // do some test
 *      var rootSvg = document.getDocumentElement();
 *      var result = document.createElementNS("http://xml.apache.org/batik/test",
 *                                            "testResult");
 *      result.setAttributeNS(null, "result", "failed");
 *      result.setAttributeNS(null, "errorCode", "org.apache.batik.css.dom.wrong.computed.value");
 *      rootSvg.appendChild(result);
 *   }
 * &lt;/script&gt;
 * &lt;/svg&gt;</code>
 *
 * @author <a href="mailto:vhardy@apache.org">Vincent Hardy</a>
 * @version $Id$
 */
public class SelfContainedSVGOnLoadTest extends AbstractTest {
    /**
     * Error when the input file cannot be loaded into a
     * Document object
     * {0} = IOException message
     */
    public static final String ERROR_CANNOT_LOAD_SVG_DOCUMENT
        = "SelfContainedSVGOnLoadTest.error.cannot.load.svg.document";

    /**
     * Error while building the GVT tree or dispatching the 
     * 'onload' event.
     */
    public static final String ERROR_WHILE_PROCESSING_SVG_DOCUMENT
        = "SelfContainedSVGOnLoadTest.error.while.processing.svg.document";

    /**
     * There is either 0 or more than one <testResult> elements in
     * the document after dispatching the onload event.
     */
    public static final String ERROR_UNEXPECTED_NUMBER_OF_TEST_RESULT_ELEMENTS
        = "SelfContainedSVGOnLoadTest.error.unexpected.number.of.test.result.elements";

    /**
     * The 'result' attribute value is neither 'passed' nor 'failed'
     */
    public static final String ERROR_UNEXPECTED_RESULT_VALUE
        = "SelfContainedSVGOnLoadTest.error.unexpected.result.value";

    /**
     * The result was 'failed' but there was no 'errorCode' attribute or
     * it was the empty string
     */
    public static final String ERROR_MISSING_OR_EMPTY_ERROR_CODE_ON_FAILED_TEST
        = "SelfContainedSVGOnLoadTest.error.missing.or.empty.error.code.on.failed.test";

    /**
     * Entry describing the error
     */
    public static final String ENTRY_KEY_ERROR_DESCRIPTION 
        = "SelfContainedSVGOnLoadTest.entry.key.error.description";

    /**
     * Entry describing the number of testResult elements found in the 
     * document after dispatching onload.
     */
    public static final String ENTRY_KEY_NUMBER_OF_TEST_RESULT_ELEMENTS
        = "SelfContainedSVGOnLoadTest.entry.key.number.of.test.result.elements";

    /**
     * Entry describing the result value (different from 'passed' or 'failed'
     * found in the 'result' attribute.
     */
    public static final String ENTRY_KEY_RESULT_VALUE
        = "SelfContainedSVGOnLoadTest.entry.key.result.value";

    /**
     * Test Namespace
     */
    public static final String testNS = "http://xml.apache.org/batik/test";

    /**
     * Test Constants
     */
    public static final String TAG_TEST_RESULT = "testResult";
    public static final String TAG_ERROR_DESCRIPTION_ENTRY = "errorDescriptionEntry";
    public static final String ATTRIBUTE_RESULT = "result";
    public static final String ATTRIBUTE_KEY = "id";
    public static final String ATTRIBUTE_VALUE = "value";
    public static final String TEST_RESULT_PASSED = "passed";
    public static final String TEST_RESULT_FAILED = "failed";

    /**
     * The URL for the input SVG document to be tested
     */
    protected String svgURL;

    /**
     * @param svgURL the URL string for the SVG document being tested
     */
    public SelfContainedSVGOnLoadTest(String svgURL){
        this.svgURL = resolveURL(svgURL);
    }

    /**
     * Default constructor
     */
    protected SelfContainedSVGOnLoadTest(){
    }

    /**
     * Resolves the input string as follows.
     * + First, the string is interpreted as a file description.
     *   If the file exists, then the file name is turned into
     *   a URL.
     * + Otherwise, the string is supposed to be a URL. If it
     *   is an invalid URL, an IllegalArgumentException is thrown.
     */
    protected String resolveURL(String url){
        // Is url a file?
        File f = (new File(url)).getAbsoluteFile();
        if(f.getParentFile().exists()){
            try{
                return f.toURI().toURL().toString();
            }catch(MalformedURLException e){
                throw new IllegalArgumentException();
            }
        }
        
        // url is not a file. It must be a regular URL...
        try{
            return (new URL(url)).toString();
        }catch(MalformedURLException e){
            throw new IllegalArgumentException(url);
        }
    }


    /**
     * Run this test and produce a report.
     * The test goes through the following steps: <ul>
     * <li>load the input SVG into a Document</li>
     * <li>build the GVT tree corresponding to the 
     *     Document and dispatch the 'onload' event</li>
     * <li>looks for one and only one &lt;testResult&gt; element in
     *     the Document. This is used to build the returned 
     *     TestReport</li>
     * </ul>
     *
     */
    public TestReport runImpl() throws Exception{
        DefaultTestReport report 
            = new DefaultTestReport(this);

        //
        // First step: 
        //
        // Load the input SVG into a Document object
        //
        String parserClassName = XMLResourceDescriptor.getXMLParserClassName();
        SAXSVGDocumentFactory f = new SAXSVGDocumentFactory(parserClassName);
        Document doc = null;

        try {
            doc = f.createDocument(svgURL);
        } catch(IOException e){
            report.setErrorCode(ERROR_CANNOT_LOAD_SVG_DOCUMENT);
            report.addDescriptionEntry(ENTRY_KEY_ERROR_DESCRIPTION,
                                       e.getMessage());
            report.setPassed(false);
            return report;
        } catch(Exception e){
            report.setErrorCode(ERROR_CANNOT_LOAD_SVG_DOCUMENT);
            report.addDescriptionEntry(ENTRY_KEY_ERROR_DESCRIPTION,
                                       e.getMessage());
            report.setPassed(false);
            return report;
        }

        //
        // Second step:
        // 
        // Now that the SVG file has been loaded, build
        // a GVT Tree from it
        //
        UserAgent userAgent = buildUserAgent();
        GVTBuilder builder = new GVTBuilder();
        BridgeContext ctx = new BridgeContext(userAgent);
        ctx.setDynamic(true);

        try {
            builder.build(ctx, doc);
            BaseScriptingEnvironment scriptEnvironment 
                = new BaseScriptingEnvironment(ctx);
            scriptEnvironment.loadScripts();
            scriptEnvironment.dispatchSVGLoadEvent();
        } catch (BridgeException e){
            e.printStackTrace();
            report.setErrorCode(ERROR_WHILE_PROCESSING_SVG_DOCUMENT);
            report.addDescriptionEntry(ENTRY_KEY_ERROR_DESCRIPTION,
                                       e.getMessage());
            report.setPassed(false);
            return report;
        } catch(Exception e){
            e.printStackTrace();
            report.setErrorCode(ERROR_WHILE_PROCESSING_SVG_DOCUMENT);
            report.addDescriptionEntry(ENTRY_KEY_ERROR_DESCRIPTION,
                                       e.getMessage());
            report.setPassed(false);
            return report;
        }

        //
        // Final step:
        //
        // Look for one and only one <testResult> element
        //
        NodeList testResultList = doc.getElementsByTagNameNS(testNS,
                                                             TAG_TEST_RESULT);

        // Check that there is one and only one testResult element
        if(testResultList.getLength() != 1){
            report.setErrorCode(ERROR_UNEXPECTED_NUMBER_OF_TEST_RESULT_ELEMENTS);
            report.addDescriptionEntry(ENTRY_KEY_NUMBER_OF_TEST_RESULT_ELEMENTS,
                                  "" + testResultList.getLength());
            report.setPassed(false);
            return report;
        }

        Element testResult = (Element)testResultList.item(0);
        
        // Now, get the result attribute. Whould be either "passed" or "failed"
        String result = testResult.getAttributeNS(null, ATTRIBUTE_RESULT);
        boolean passed = true;
        if(TEST_RESULT_PASSED.equals(result)){
            // OK
        } else if (TEST_RESULT_FAILED.equals(result)){
            passed = false;
        } else {
            report.setErrorCode(ERROR_UNEXPECTED_RESULT_VALUE);
            report.addDescriptionEntry(ENTRY_KEY_RESULT_VALUE, result);
            report.setPassed(false);
            return report;
        }

        // If the test failed, then there should be an error code
        if( !passed ){
            String errorCode = testResult.getAttributeNS(null, "errorCode");
            if("".equals(errorCode)){
                report.setErrorCode(ERROR_MISSING_OR_EMPTY_ERROR_CODE_ON_FAILED_TEST);
                report.setPassed(false);
                return report;
            }

            // We got an error code, set it on the report object
            report.setErrorCode(errorCode);

            // Now, add descriptions from children <errorDescriptionEntry> elements
            NodeList desc = testResult.getElementsByTagNameNS(testNS,
                                                              TAG_ERROR_DESCRIPTION_ENTRY);
            int nDesc = desc.getLength();
            for (int i=0; i<nDesc; i++){
                Element entry = (Element)desc.item(i);
                String key = entry.getAttributeNS(null, ATTRIBUTE_KEY);
                String value = entry.getAttributeNS(null, ATTRIBUTE_VALUE);
                report.addDescriptionEntry(key, value);
            }
            report.setPassed(false);
            return report;
        }

        return report;
    }

    /**
     * Give subclasses a chance to build their own UserAgent
     */
    protected UserAgent buildUserAgent(){
        return new UserAgentAdapter();
    }

}