package ever.pipeline;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.util.HashSet;
import java.util.Iterator;
import java.util.NoSuchElementException;

import javax.xml.transform.stream.StreamSource;

import net.sf.saxon.s9api.DocumentBuilder;
import net.sf.saxon.s9api.Processor;
import net.sf.saxon.s9api.QName;
import net.sf.saxon.s9api.SaxonApiException;
import net.sf.saxon.s9api.Serializer;
import net.sf.saxon.s9api.XPathCompiler;
import net.sf.saxon.s9api.XPathExecutable;
import net.sf.saxon.s9api.XPathSelector;
import net.sf.saxon.s9api.XQueryCompiler;
import net.sf.saxon.s9api.XQueryEvaluator;
import net.sf.saxon.s9api.XQueryExecutable;
import net.sf.saxon.s9api.XdmAtomicValue;
import net.sf.saxon.s9api.XdmItem;
import net.sf.saxon.s9api.XdmNode;
import net.sf.saxon.xpath.XPathEvaluator;

/**
 * 
 * This class handles the access of the extraction tool to
 *         the xml file.
 * 
 */
public class XmlHandler {

	// node with the recipe
	private static XdmNode input;
	private static Processor proc = new Processor(false);
	private static File in;

	/**
	 * Configure handler for a new file
	 * 
	 * @param inf
	 */
	public static void setInputFile(File inf) {
		in = inf;
		DocumentBuilder newDocumentBuilder = proc.newDocumentBuilder();
		try {
			input = newDocumentBuilder.build(new StreamSource(
					new FileInputStream(in)));
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (SaxonApiException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	/**
	 * Copies the text between the <steps> tags in a text file in order that it
	 * can be processed by the sundance tool
	 */
	public static void copyPrepTextToSundanceInput() {
		String query = "let $steps:=/howto/steps/step \n"
				+ "for $i in $steps\n"
				+ "for $token at $index in tokenize($i,'\"') \n" + "return \n"
				+ "   if( $index mod 2=0) \n"
				+ "   then replace($token,' ','_')\n" + "   else $token";

		XQueryCompiler newXQueryCompiler = proc.newXQueryCompiler();
		XQueryExecutable compile = null;
		try {
			compile = newXQueryCompiler.compile(query);

			XQueryEvaluator load = compile.load();
			load.setContextItem(input);
			Serializer serial = new Serializer();
			FileOutputStream outs;
			outs = new FileOutputStream("singlePrep.txt");
			serial.setOutputStream(outs);
			serial.setOutputProperty(Serializer.Property.METHOD, "text");
			serial.setOutputProperty(Serializer.Property.OMIT_XML_DECLARATION,
					"yes");
			serial.setOutputProperty(Serializer.Property.ENCODING, "utf-8");
			load.run(serial);
			// System.out.println("Copying file.");
		} catch (SaxonApiException e) {
			//
			System.err.println("Current file: " + in.getAbsolutePath());
			e.printStackTrace();
			in.renameTo(new File(in.getAbsolutePath().replace("&", " and ")));

		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			System.err.println("Current file: " + in.getAbsolutePath());
			e.printStackTrace();
		} catch (Exception ex) {
			System.err.println("Current file: " + in.getAbsolutePath());
		}
	}

	/**
	 * Copies the text between the <steps> tags in of the string in order that
	 * it can be processed by the sundance tool
	 */
	public static void copyPrepTextToSundanceInput(String xmlSource) {
		String query = "let $steps:=/howto/steps/step \n"
				+ "for $i in $steps\n"
				+ "for $token at $index in tokenize($i,'\"') \n" + "return \n"
				+ "   if( $index mod 2=0) \n"
				+ "   then replace($token,' ','_')\n" + "   else $token";

		XQueryCompiler newXQueryCompiler = proc.newXQueryCompiler();
		DocumentBuilder newDocumentBuilder = proc.newDocumentBuilder();
		XdmNode doc = null;
		XQueryExecutable compile = null;
		try {
			try {
				doc = newDocumentBuilder.build(new StreamSource(
						new ByteArrayInputStream(xmlSource.getBytes())));
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			compile = newXQueryCompiler.compile(query);
			XQueryEvaluator load = compile.load();
			load.setContextItem(doc);
			Serializer serial = new Serializer();
			FileOutputStream outs;
			outs = new FileOutputStream("singlePrep.txt");
			serial.setOutputStream(outs);
			serial.setOutputProperty(Serializer.Property.METHOD, "text");
			serial.setOutputProperty(Serializer.Property.OMIT_XML_DECLARATION,
					"yes");
			serial.setOutputProperty(Serializer.Property.ENCODING, "utf-8");
			load.run(serial);
		} catch (SaxonApiException ex) {
			ex.printStackTrace();
		} catch (FileNotFoundException fne)
		{
			fne.printStackTrace();
		}
		// System.out.println("Copying file.");

	}

	/**
	 * Tests if a step starts with "Meanwhile"
	 * @param raw
	 * @return
	 */
	public static boolean isMeanwhileStep(String raw) {
		String query = "declare variable $sentence as xs:string external; \n"
				+ "let $steps := /howto/steps/step \n"
				+ "for $i at $index in $steps \n"
				+ "return if(starts-with($i,\"Meanwhile \") and contains($i,$sentence)) \n"
				+ "then \"true\" \n" + "else \"\"";

		XQueryCompiler newXQueryCompiler = proc.newXQueryCompiler();
		XQueryExecutable compile = null;
		try {
			compile = newXQueryCompiler.compile(query);

			XQueryEvaluator load = compile.load();

			load.setContextItem(input);
			load.setExternalVariable(new QName("sentence"), new XdmAtomicValue(
					raw));
			Serializer serial = new Serializer();
			ByteArrayOutputStream outs = new ByteArrayOutputStream();
			serial.setOutputStream(outs);
			serial.setOutputProperty(Serializer.Property.METHOD, "text");
			serial.setOutputProperty(Serializer.Property.OMIT_XML_DECLARATION,
					"yes");
			serial.setOutputProperty(Serializer.Property.ENCODING, "utf-8");
			load.run(serial);
			boolean ret = false;
			try {
				ret = Boolean.parseBoolean(outs.toString().trim());
			} catch (NumberFormatException ex) {
			}
			// System.out.println(ret);
			return ret;
		} catch (SaxonApiException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return false;
		}
	}

	/**
	 * Tests if a step is preceding a Meanwhile step
	 * @param raw
	 * @return
	 */
	public static int isPreMeanwhileStep(String raw) {
		String query = "declare variable $sentence as xs:string external; \n"
				+ "let $steps := /howto/steps/step \n"
				+ "for $i at $index in $steps \n"
				+ "return if(starts-with($i/following::step[position()=1]/text(),\"Meanwhile \") and contains($i,$sentence)) \n"
				+ "then $index \n" + "else \"\"";

		XQueryCompiler newXQueryCompiler = proc.newXQueryCompiler();
		XQueryExecutable compile = null;
		try {
			compile = newXQueryCompiler.compile(query);

			XQueryEvaluator load = compile.load();

			load.setContextItem(input);
			load.setExternalVariable(new QName("sentence"), new XdmAtomicValue(
					raw));
			Serializer serial = new Serializer();
			ByteArrayOutputStream outs = new ByteArrayOutputStream();
			serial.setOutputStream(outs);
			serial.setOutputProperty(Serializer.Property.METHOD, "text");
			serial.setOutputProperty(Serializer.Property.OMIT_XML_DECLARATION,
					"yes");
			serial.setOutputProperty(Serializer.Property.ENCODING, "utf-8");
			load.run(serial);
			int ret = -1;
			try {
				ret = Integer.parseInt(outs.toString().trim());
			} catch (NumberFormatException ex) {
			}

			return ret;
		} catch (SaxonApiException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return -1;
		}
	}

	/**
	 * Tests if the keyword "optional" is in an ingredient
	 * @param ing
	 * @return
	 */
	public static boolean isIngOptional(String ing) {
		String query = "declare variable $ing as xs:string external; \n"
				+ "let $prod := /howto/products/product[contains(text(),$ing)] \n"
				+ "for $i at $index in $prod \n"
				+ "return if(contains($i,\"(optional)\")) \n"
				+ "then \"true\" \n" + "else \"\"";

		XQueryCompiler newXQueryCompiler = proc.newXQueryCompiler();
		XQueryExecutable compile = null;
		try {
			compile = newXQueryCompiler.compile(query);

			XQueryEvaluator load = compile.load();

			load.setContextItem(input);
			load.setExternalVariable(new QName("ing"), new XdmAtomicValue(ing));
			Serializer serial = new Serializer();
			ByteArrayOutputStream outs = new ByteArrayOutputStream();
			serial.setOutputStream(outs);
			serial.setOutputProperty(Serializer.Property.METHOD, "text");
			serial.setOutputProperty(Serializer.Property.OMIT_XML_DECLARATION,
					"yes");
			serial.setOutputProperty(Serializer.Property.ENCODING, "utf-8");
			load.run(serial);
			boolean ret = false;
			try {
				ret = Boolean.parseBoolean(outs.toString().trim());
			} catch (NumberFormatException ex) {
			}
			// System.out.println(ing+" "+ret);
			return ret;
		} catch (SaxonApiException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return false;
		}

	}

	/**
	 * Returns the product/ingredient list of a process description
	 * @param xmlSource
	 * @return
	 */
	public static HashSet<String> getProductList(String xmlSource) {
		HashSet<String> ret = new HashSet<String>();
		String query = "/howto/products/product";
		DocumentBuilder newDocumentBuilder = proc.newDocumentBuilder();
		XdmNode doc = null;
		try {
			doc = newDocumentBuilder.build(new StreamSource(
					new ByteArrayInputStream(xmlSource.getBytes())));
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		XPathExecutable exec = null;
		XPathCompiler xpath = proc.newXPathCompiler();
		try {
			exec = xpath.compile(query);
			XPathSelector eval = exec.load();
			eval.setContextItem(doc);
			eval.evaluate();
			Iterator<XdmItem> it = eval.iterator();
			XdmItem current = null;
			if (it.hasNext()) {
				current = it.next();
			}

			while (current != null) {
				ret.add(current.getStringValue());
				try {
					current = it.next();
				} catch (NoSuchElementException ex) {
					break;
				}

			}

		} catch (SaxonApiException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		return ret;

	}

}