/*
 * 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.jmeter.assertions;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Serializable;
import java.io.StringWriter;
import java.text.MessageFormat;

import org.apache.commons.io.IOUtils;
import org.apache.jmeter.samplers.SampleResult;
import org.apache.jmeter.testelement.AbstractTestElement;
import org.apache.jmeter.testelement.property.BooleanProperty;
import org.apache.jmeter.testelement.property.LongProperty;
import org.apache.jmeter.testelement.property.StringProperty;
import org.apache.jmeter.util.JMeterUtils;
import org.apache.jorphan.logging.LoggingManager;
import org.apache.log.Logger;
import org.w3c.tidy.Node;
import org.w3c.tidy.Tidy;

/**
 * Assertion to validate the response of a Sample with Tidy.
 */
public class HTMLAssertion extends AbstractTestElement implements Serializable, Assertion {

    private static final Logger log = LoggingManager.getLoggerForClass();

	public static final String DEFAULT_DOCTYPE = "omit"; //$NON-NLS-1$

	public static final String DOCTYPE_KEY = "html_assertion_doctype"; //$NON-NLS-1$

	public static final String ERRORS_ONLY_KEY = "html_assertion_errorsonly"; //$NON-NLS-1$

	public static final String ERROR_THRESHOLD_KEY = "html_assertion_error_threshold"; //$NON-NLS-1$

	public static final String WARNING_THRESHOLD_KEY = "html_assertion_warning_threshold"; //$NON-NLS-1$

	public static final String FORMAT_KEY = "html_assertion_format"; //$NON-NLS-1$

	public static final String FILENAME_KEY = "html_assertion_filename"; //$NON-NLS-1$

	/**
	 * 
	 */
	public HTMLAssertion() {
		log.debug("HTMLAssertion(): called");
	}

	/**
	 * Returns the result of the Assertion. If so an AssertionResult containing
	 * a FailureMessage will be returned. Otherwise the returned AssertionResult
	 * will reflect the success of the Sample.
	 */
	public AssertionResult getResult(SampleResult inResponse) {
		log.debug("HTMLAssertions.getResult() called");

		// no error as default
		AssertionResult result = new AssertionResult(getName());

		if (inResponse.getResponseData().length == 0) {
			return result.setResultForNull();
		}

		result.setFailure(false);

		// create parser
		Tidy tidy = null;
		try {
			log.debug("HTMLAssertions.getResult(): Setup tidy ...");
			log.debug("doctype: " + getDoctype());
			log.debug("errors only: " + isErrorsOnly());
			log.debug("error threshold: " + getErrorThreshold());
			log.debug("warning threshold: " + getWarningThreshold());
			log.debug("html mode: " + isHTML());
			log.debug("xhtml mode: " + isXHTML());
			log.debug("xml mode: " + isXML());
			tidy = new Tidy();
			tidy.setCharEncoding(org.w3c.tidy.Configuration.UTF8);
			tidy.setQuiet(false);
			tidy.setShowWarnings(true);
			tidy.setOnlyErrors(isErrorsOnly());
			tidy.setDocType(getDoctype());
			if (isXHTML()) {
				tidy.setXHTML(true);
			} else if (isXML()) {
				tidy.setXmlTags(true);
			}
			log.debug("err file: " + getFilename());
			tidy.setErrfile(getFilename());

			if (log.isDebugEnabled()) {
				log.debug("getParser : tidy parser created - " + tidy);
			}
			log.debug("HTMLAssertions.getResult(): Tidy instance created!");

		} catch (Exception e) {//TODO replace with proper Exception
			log.error("Unable to instantiate tidy parser", e);
			result.setFailure(true);
			result.setFailureMessage("Unable to instantiate tidy parser");
			// return with an error
			return result;
		}

		/*
		 * Run tidy.
		 */
		try {
			log.debug("HTMLAssertions.getResult(): start parsing with tidy ...");

			StringWriter errbuf = new StringWriter();
			tidy.setErrout(new PrintWriter(errbuf));
			// Node node = tidy.parseDOM(new
			// ByteArrayInputStream(response.getResponseData()), null);
			ByteArrayOutputStream os = new ByteArrayOutputStream();
			log.debug("Start : parse");
			Node node = tidy.parse(new ByteArrayInputStream(inResponse.getResponseData()), os);
			if (log.isDebugEnabled()) {
				log.debug("node : " + node);
			}
			log.debug("End   : parse");
			log.debug("HTMLAssertions.getResult(): parsing with tidy done!");
			log.debug("Output: " + os.toString());

			// write output to file
			writeOutput(errbuf.toString());

			// evaluate result
			if ((tidy.getParseErrors() > getErrorThreshold())
					|| (!isErrorsOnly() && (tidy.getParseWarnings() > getWarningThreshold()))) {
				log.debug("HTMLAssertions.getResult(): errors/warnings detected:");
				log.debug(errbuf.toString());
				result.setFailure(true);
				result.setFailureMessage(MessageFormat.format("Tidy Parser errors:   " + tidy.getParseErrors()
						+ " (allowed " + getErrorThreshold() + ") " + "Tidy Parser warnings: "
						+ tidy.getParseWarnings() + " (allowed " + getWarningThreshold() + ")", new Object[0]));
				// return with an error

			} else if ((tidy.getParseErrors() > 0) || (tidy.getParseWarnings() > 0)) {
				// return with no error
				log.debug("HTMLAssertions.getResult(): there were errors/warnings but threshold to high");
				result.setFailure(false);
			} else {
				// return with no error
				log.debug("HTMLAssertions.getResult(): no errors/warnings detected:");
				result.setFailure(false);
			}

		} catch (Exception e) {//TODO replace with proper Exception
			// return with an error
			log.warn("Cannot parse result content", e);
			result.setFailure(true);
			result.setFailureMessage(e.getMessage());
		}
		return result;
	}

	/**
	 * Writes the output of tidy to file.
	 * 
	 * @param inOutput
	 */
	private void writeOutput(String inOutput) {
		String lFilename = getFilename();

		// check if filename defined
		if ((lFilename != null) && (!"".equals(lFilename.trim()))) {
			FileWriter lOutputWriter = null;
			try {

				// open file
				lOutputWriter = new FileWriter(lFilename, false);

				// write to file
				lOutputWriter.write(inOutput);

				// flush
				lOutputWriter.flush();

				log.debug("writeOutput() -> output successfully written to file " + lFilename);

			} catch (IOException ex) {
				log.warn("writeOutput() -> could not write output to file " + lFilename, ex);
			} finally {
				// close file
			    IOUtils.closeQuietly(lOutputWriter);
			}
		}
	}

	/**
	 * Gets the doctype
	 * 
	 * @return the documemt type
	 */
	public String getDoctype() {
		return getPropertyAsString(DOCTYPE_KEY);
	}

	/**
	 * Check if errors will be reported only
	 * 
	 * @return boolean - report errors only?
	 */
	public boolean isErrorsOnly() {
		return getPropertyAsBoolean(ERRORS_ONLY_KEY);
	}

	/**
	 * Gets the threshold setting for errors
	 * 
	 * @return long error threshold
	 */
	public long getErrorThreshold() {
		return getPropertyAsLong(ERROR_THRESHOLD_KEY);
	}

	/**
	 * Gets the threshold setting for warnings
	 * 
	 * @return long warning threshold
	 */
	public long getWarningThreshold() {
		return getPropertyAsLong(WARNING_THRESHOLD_KEY);
	}

	/**
	 * Sets the doctype setting
	 * 
	 * @param inDoctype
	 */
	public void setDoctype(String inDoctype) {
		if ((inDoctype == null) || (inDoctype.trim().equals(""))) {
			setProperty(new StringProperty(DOCTYPE_KEY, DEFAULT_DOCTYPE));
		} else {
			setProperty(new StringProperty(DOCTYPE_KEY, inDoctype));
		}
	}

	/**
	 * Sets if errors shoud be tracked only
	 * 
	 * @param inErrorsOnly
	 */
	public void setErrorsOnly(boolean inErrorsOnly) {
		setProperty(new BooleanProperty(ERRORS_ONLY_KEY, inErrorsOnly));
	}

	/**
	 * Sets the threshold on error level
	 * 
	 * @param inErrorThreshold
	 */
	public void setErrorThreshold(long inErrorThreshold) {
		if (inErrorThreshold < 0L) {
			throw new IllegalArgumentException(JMeterUtils.getResString("argument_must_not_be_negative")); //$NON-NLS-1$
		}
		if (inErrorThreshold == Long.MAX_VALUE) {
			setProperty(new LongProperty(ERROR_THRESHOLD_KEY, 0));
		} else {
			setProperty(new LongProperty(ERROR_THRESHOLD_KEY, inErrorThreshold));
		}
	}

	/**
	 * Sets the threshold on warning level
	 * 
	 * @param inWarningThreshold
	 */
	public void setWarningThreshold(long inWarningThreshold) {
		if (inWarningThreshold < 0L) {
			throw new IllegalArgumentException(JMeterUtils.getResString("argument_must_not_be_negative")); //$NON-NLS-1$
		}
		if (inWarningThreshold == Long.MAX_VALUE) {
			setProperty(new LongProperty(WARNING_THRESHOLD_KEY, 0));
		} else {
			setProperty(new LongProperty(WARNING_THRESHOLD_KEY, inWarningThreshold));
		}
	}

	/**
	 * Enables html validation mode
	 */
	public void setHTML() {
		setProperty(new LongProperty(FORMAT_KEY, 0));
	}

	/**
	 * Check if html validation mode is set
	 * 
	 * @return boolean
	 */
	public boolean isHTML() {
		return getPropertyAsLong(FORMAT_KEY) == 0;
	}

	/**
	 * Enables xhtml validation mode
	 */
	public void setXHTML() {
		setProperty(new LongProperty(FORMAT_KEY, 1));
	}

	/**
	 * Check if xhtml validation mode is set
	 * 
	 * @return boolean
	 */
	public boolean isXHTML() {
		return getPropertyAsLong(FORMAT_KEY) == 1;
	}

	/**
	 * Enables xml validation mode
	 */
	public void setXML() {
		setProperty(new LongProperty(FORMAT_KEY, 2));
	}

	/**
	 * Check if xml validation mode is set
	 * 
	 * @return boolean
	 */
	public boolean isXML() {
		return getPropertyAsLong(FORMAT_KEY) == 2;
	}

	/**
	 * Sets the name of the file where tidy writes the output to
	 * 
	 * @return name of file
	 */
	public String getFilename() {
		return getPropertyAsString(FILENAME_KEY);
	}

	/**
	 * Sets the name of the tidy output file
	 * 
	 * @param inName
	 */
	public void setFilename(String inName) {
		setProperty(FILENAME_KEY, inName);
	}
}
