// Copyright (c) 2008 Fabien DUMINY (fduminy@jnode.org)
// Modified by Levente S\u00e1ntha (lsantha@jnode.org)

// This file is part of Mauve.

// Mauve 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; either version 2, or (at your option)
// any later version.

// Mauve 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 Mauve; see the file COPYING.  If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330,
// Boston, MA 02111-1307, USA.  */

package gnu.testlet.runner;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;
import java.util.Enumeration;

import net.sourceforge.nanoxml.XMLElement;
import net.sourceforge.nanoxml.XMLParseException;

/**
 * XML parser for mauve reports.
 * 
 * @author fabien
 *
 */
public class XMLReportParser implements XMLReportConstants {
    /**
     * Parse the given file and return the corresponding mauve result. 
     * 
     * @param input
     * @return
     * @throws XMLParseException
     * @throws IOException
     */
    public RunResult parse(File input) throws XMLParseException, IOException {
        return parse(new FileReader(input));
    }
    
    /**
     * Parse the given reader and return the corresponding mauve result. 
     * 
     * @param r
     * @return
     * @throws XMLParseException
     * @throws IOException
     */
    public RunResult parse(Reader r) throws XMLParseException, IOException {
        XMLElement xmlRun = new XMLElement();
        BufferedReader reader = null;
        
        try {
            reader = new BufferedReader(r);
            xmlRun.parseFromReader(reader);
    
            checkTag(xmlRun, RUN_RESULT);
            
            String attr;
            RunResult run = new RunResult(getValue(xmlRun, RUN_NAME, ""));
            
            for (Enumeration enumPkg = xmlRun.enumerateChildren(); enumPkg.hasMoreElements(); ) {
                XMLElement xmlPkg = (XMLElement) enumPkg.nextElement();
                int indexTag = checkTag(xmlPkg, new String[]{PACKAGE_RESULT, PROPERTY});
                
                if (indexTag == 1) {
                    String name  = getValue(xmlPkg, PROPERTY_NAME, "");
                    String value  = getValue(xmlPkg, PROPERTY_VALUE, "");
                    run.setSystemProperty(name, value);
                    continue;
                }
                
                attr = getValue(xmlPkg, PACKAGE_NAME, "");
                PackageResult pkg = new PackageResult(attr);             
                run.add(pkg);
                
                for (Enumeration enumCls = xmlPkg.enumerateChildren(); enumCls.hasMoreElements(); ) {
                    XMLElement xmlCls = (XMLElement) enumCls.nextElement();
                    checkTag(xmlCls, CLASS_RESULT);
                    
                    attr = getValue(xmlCls, CLASS_NAME, "");
                    ClassResult cls = new ClassResult(attr);
                    pkg.add(cls);
                    
                    for (Enumeration enumTest = xmlCls.enumerateChildren(); enumTest.hasMoreElements(); ) {
                        XMLElement xmlTest = (XMLElement) enumTest.nextElement();
                        checkTag(xmlTest, TEST_RESULT);
                        
                        attr = getValue(xmlTest, TEST_NAME, "");
                        TestResult test = new TestResult(attr);
                        cls.add(test);
                        
                        for (Enumeration enumCheck = xmlTest.enumerateChildren(); enumCheck.hasMoreElements(); ) {
                            XMLElement xmlCheck = (XMLElement) enumCheck.nextElement();
                            if (TEST_ERROR.equals(xmlCheck.getName())) {
                                test.setFailedMessage(xmlCheck.getContent());
                            } else {
                                checkTag(xmlCheck, CHECK_RESULT);
                                
                                test.add(createCheck(xmlCheck));
                            }
                        }
                    }
                }
            }
            
            return run;
        } finally {
            if (reader != null) {
                reader.close();
            }
        }
    }
    
    private CheckResult createCheck(XMLElement xmlCheck) {
        String attr = getValue(xmlCheck, CHECK_NUMBER, "-1");
        int number = Integer.valueOf(attr).intValue();
        
        attr = getValue(xmlCheck, CHECK_PASSED, "false");
        boolean passed = Boolean.valueOf(attr).booleanValue();
        
        CheckResult check = new CheckResult(number, passed);
        
        attr = getValue(xmlCheck, CHECK_POINT, "");
        check.setCheckPoint(attr);
        
        attr = getValue(xmlCheck, CHECK_EXPECTED, "");
        check.setExpected(attr);
        
        attr = getValue(xmlCheck, CHECK_ACTUAL, "");
        check.setActual(attr);
        
        // get the log if any
        if (xmlCheck.countChildren() > 0) {
            XMLElement firstChild = (XMLElement) xmlCheck.enumerateChildren().nextElement();
            checkTag(firstChild, CHECK_LOG);
            
            String content = firstChild.getContent(); 
            if (content != null) {
                check.appendToLog(attr);
            }
        }
    
        return check;
    }

    /**
     * Get the value of an xml element's attribute and return the given default
     * value if the attribute is not defined. 
     * @param xml The xml element for which we want an attribute.
     * @param attributeName The name of the attribute.
     * @param defaultValue The default value to return if the attribute is not defined.
     * @return The value of the xml element's attribute or, if not defined, the given
     * <code>defaultValue</code> parameter. 
     */
    private String getValue(XMLElement xml, String attributeName, String defaultValue) {
        Object attr = xml.getAttribute(attributeName);
        return (attr == null) ? defaultValue : String.valueOf(attr);
    }
    
    /**
     * Checks that the xml element represents the given tag.
     * @param xml The xml element to check.
     * @param tag The tag which is expected.
     * @throws XMLParseException if the xml element doesn't represent the given tag.
     */
    private void checkTag(XMLElement xml, String tag) {
        final String actualTag = xml.getName();
        if (!tag.equals(actualTag)) {
            throw new XMLParseException("", "tag is not '" + tag + "' (actual: '" + actualTag + "')");
        }        
    }
    
    /**
     * Checks that the xml element represents one of the given tags.
     * @param xml The xml element to check.
     * @param tag The tags which are expected.
     * @throws XMLParseException if the xml element doesn't represent one of the given tags.
     */
    private int checkTag(XMLElement xml, String[] tags) {
        final String actualTag = xml.getName();
        int indexTag = -1;
        for (int i = 0; i < tags.length; i++) {
            if (tags[i].equals(actualTag)) {
                indexTag = i;
                break;
            }
        }
        
        if (indexTag < 0) {
            StringBuffer sb = new StringBuffer('(');
            for (int i = 0; i < tags.length; i++) {
                if (i > 0) {
                    sb.append(',');
                }
                sb.append(tags[i]);
            }
            sb.append(')');
            throw new XMLParseException("", "tag is not one of " + sb.toString() + " (actual: '" + actualTag + "')");
        }
        
        return indexTag;
    }
}