package net.sourceforge.phpeclipse.phpeditor;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import net.sourceforge.phpeclipse.IPreferenceConstants;
import net.sourceforge.phpeclipse.PHPeclipsePlugin;
import net.sourceforge.phpeclipse.phpeditor.php.PHPConstant;
import net.sourceforge.phpeclipse.phpeditor.php.PHPElement;
import net.sourceforge.phpeclipse.phpeditor.php.PHPFunction;
import net.sourceforge.phpeclipse.phpeditor.php.PHPKeyword;
import net.sourceforge.phpeclipse.phpeditor.php.PHPType;

import org.apache.xml.serialize.OutputFormat;
import org.apache.xml.serialize.Serializer;
import org.apache.xml.serialize.SerializerFactory;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.jface.preference.IPreferenceStore;
import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

/**
 * <code>PHPSyntaxRdr</code> reads PHP specifics from an XML file (eg. keywords) 
 */

public class PHPSyntaxRdr {
	private static final String PHPDEFAULT_FILE = "default-phpsyntax.xml"; //$NON-NLS-1$
	private static final String PHPSYNTAX_FILE = "phpsyntax.xml"; //$NON-NLS-1$
	private static final String USERSYNTAX_FILE = "usersyntax.xml"; //$NON-NLS-1$
	private static final String USERDEFAULT_FILE = "default-usersyntax.xml"; //$NON-NLS-1$
	private static final String PHPSYNTAX_TAG = "phpsyntax"; //$NON-NLS-1$
	private static final String KEYWORD_ATTR = "keyword"; //$NON-NLS-1$
	private static final String TYPE_ATTR = "type"; //$NON-NLS-1$
	private static final String CONSTANT_ATTR = "constant"; //$NON-NLS-1$
	private static final String FN_ATTR = "function"; //$NON-NLS-1$
	private static final String USAGE_ATTR = "usage"; //$NON-NLS-1$
	private static final String TOKENVAL_ATTR = "tokenval"; //$NON-NLS-1$
	private static IPreferenceStore store;
	private static boolean hasXMLFileBeenRead = true;

	//The following variable is used to hold the syntax from
	//the suers custom file - if that file should be changed,
	//then all entries in this variable should be removed from
	//the word list, reread from the file and then reinserted.
	private static ArrayList userdefsyntaxdata;

	private static ArrayList syntaxdata;

	public PHPSyntaxRdr() {
		// see getSyntaxData()
		syntaxdata = null;
		store = PHPeclipsePlugin.getDefault().getPreferenceStore();
	}

	public static void readInSyntax() {
		try {
			hasXMLFileBeenRead = true;
			/*Attempt to read the syntax file from the metadata
			 * if this does not work, create metadata from default*/
			File syntaxFile = getSyntaxFile();
			if (syntaxFile.exists()) {
				readFromFile(syntaxFile);
			} else {
				readFromStream(
					PHPSyntaxRdr.class.getResourceAsStream(PHPSYNTAX_FILE));
				saveToFile(syntaxFile);
			}
			/*Read the user-defined syntax file if it exists*/
			//String buffer = new String(store.getString(PHPeclipsePlugin.PHP_USERDEF_XMLFILE));
			if (store == null)
				store = PHPeclipsePlugin.getDefault().getPreferenceStore();
			String buffer =
				new String(
					store.getString(IPreferenceConstants.PHP_USERDEF_XMLFILE));
			if (!(buffer.equals("") || buffer == null)) {
				readFromFile(buffer);
			}
		} catch (CoreException ce) {
			ce.printStackTrace();
		}
	}

	public static void readFromFile(String filename) {
		try {
			readFromFile(new File(filename));
		} catch (CoreException e) {
		}
	}

	public static void readFromFile(File file) throws CoreException {
		InputStream stream = null;

		if (file.exists()) {
			try {
				stream = new FileInputStream(file);
				readFromStream(stream);
			} catch (IOException e) {
				throwReadException(e);
			} finally {
				try {
					if (stream != null) {
						stream.close();
					}
				} catch (IOException e) {
				}
			}
		}
	}
	public static void readFromStream(InputStream stream)
		throws CoreException {
		try {
			DocumentBuilderFactory factory =
				DocumentBuilderFactory.newInstance();
			DocumentBuilder parser = factory.newDocumentBuilder();
			Document document = parser.parse(new InputSource(stream));
			//Read in the Standard PHPSyntax "stuff"
			NodeList elements = document.getElementsByTagName(PHPSYNTAX_TAG);

			int count = elements.getLength();
			for (int i = 0; i != count; i++) {
				Node node = elements.item(i);
				NamedNodeMap attributes = node.getAttributes();

				if (attributes == null)
					continue;

				String Keyword = getAttributeValue(attributes, KEYWORD_ATTR);
				String Type = getAttributeValue(attributes, TYPE_ATTR);
				String Function = getAttributeValue(attributes, FN_ATTR);
				String Constant = getAttributeValue(attributes, CONSTANT_ATTR);
				String usage = getAttributeValue(attributes, USAGE_ATTR);
				String Tokenval = getAttributeValue(attributes, TOKENVAL_ATTR);

				StringBuffer buffer = new StringBuffer();
				NodeList children = node.getChildNodes();
				for (int j = 0; j != children.getLength(); j++) {
					String value = children.item(j).getNodeValue();
					if (value != null)
						buffer.append(value);
				}
				String description = buffer.toString().trim();

				if (Keyword == null
					&& Type == null
					&& Function == null
					&& Constant == null) {
					//ignore as it is not a valid phpsyntax tag
				} else {
					if (Keyword != null) {
						syntaxdata.add(
							new PHPKeyword(Keyword, usage, Tokenval));
					} else if (Type != null) {
						syntaxdata.add(new PHPType(Type, usage));
					} else if (Function != null) {
						syntaxdata.add(
							new PHPFunction(Function, usage, description));
					} else if (Constant != null) {
						syntaxdata.add(new PHPConstant(Constant, usage));
					}
				}
			}
		} catch (ParserConfigurationException e) {
			throwReadException(e);
		} catch (IOException e) {
			throwReadException(e);
		} catch (SAXException e) {
			throwReadException(e);
		}
	}

	public static ArrayList getSyntaxData() {
		if (syntaxdata==null) {
			syntaxdata = new ArrayList();
			readInSyntax();
		}
		return syntaxdata;
	}

	public static void replaceUserDefFile() {
		/*Replace the user-defined syntax file if it exists*/
		String buffer =
			new String(
				store.getString(IPreferenceConstants.PHP_USERDEF_XMLFILE));
		if (!buffer.equals("") || buffer == null) {
			readFromFile(buffer);
		}
	}

	public static ArrayList getUserSyntaxData() {
		return userdefsyntaxdata;
	}

	private static File getSyntaxFile() {
		IPath path = PHPeclipsePlugin.getDefault().getStateLocation();
		path = path.append(PHPSYNTAX_FILE);
		return path.toFile();
	}

	private static String getAttributeValue(
		NamedNodeMap attributes,
		String name) {
		Node node = attributes.getNamedItem(name);
		return node == null ? null : node.getNodeValue();
	}

	public static void saveToFile(File file) throws CoreException {
		OutputStream stream = null;
		try {
			stream = new FileOutputStream(file);
			saveToStream(stream);
		} catch (IOException e) {
			throwWriteException(e);
		} finally {
			try {
				if (stream != null)
					stream.close();
			} catch (IOException e) {
			}
		}
	}

	public static void saveToStream(OutputStream stream) throws CoreException {
		try {
			DocumentBuilderFactory factory =
				DocumentBuilderFactory.newInstance();
			DocumentBuilder builder = factory.newDocumentBuilder();
			Document document = builder.newDocument();
			Node root = document.createElement("PHPStandardSyntax"); // $NON-NLS-1$ //$NON-NLS-1$
			document.appendChild(root);
			for (int i = 0; i != syntaxdata.size(); i++) {
				Object bufferobj = (Object) syntaxdata.get(i);
				Attr name = null;
				Node node = document.createElement(PHPSYNTAX_TAG); // $NON-NLS-1$ //$NON-NLS-1$
				root.appendChild(node);
				NamedNodeMap attributes = node.getAttributes();
				if (bufferobj instanceof PHPType)
					name = document.createAttribute(TYPE_ATTR);
				if (bufferobj instanceof PHPKeyword)
					name = document.createAttribute(KEYWORD_ATTR);
				if (bufferobj instanceof PHPFunction)
					name = document.createAttribute(FN_ATTR);
				if (bufferobj instanceof PHPConstant)
					name = document.createAttribute(CONSTANT_ATTR);
				name.setValue(((PHPElement) bufferobj).getName());
				attributes.setNamedItem(name);
				Attr description = document.createAttribute(USAGE_ATTR);
				description.setValue(((PHPElement) bufferobj).getUsage());
				attributes.setNamedItem(description);
				if (bufferobj instanceof PHPKeyword) {
					Attr tokenval = document.createAttribute(TOKENVAL_ATTR);
					tokenval.setValue(
						(new Integer(((PHPKeyword) bufferobj).gettokenval()))
							.toString());
					attributes.setNamedItem(tokenval);
				}
				if (bufferobj instanceof PHPFunction) {
					//      Attr usage = document.createAttribute(USAGE_ATTR);
					Text usage =
						document.createTextNode(
							((PHPFunction) bufferobj).getDescription());
					node.appendChild(usage);
					//          usage.setValue(((PHPFunction) bufferobj).getUsage());
					//          attributes.setNamedItem(usage);
				}
			}
			OutputFormat format = new OutputFormat();
			format.setPreserveSpace(true);
			try {
				Serializer serializer =
					SerializerFactory.getSerializerFactory(
						"xml").makeSerializer(
						stream,
						format);
				serializer.asDOMSerializer().serialize(document);
			} catch (UnsupportedEncodingException e) {
			} catch (IOException e) {
			} //$NON-NLS-1$
			//			Serializer serializer = SerializerFactory.getSerializer().makeSerializer(stream, format); //$NON-NLS-1$
		} catch (ParserConfigurationException e) {
			throwWriteException(e);
			//        } catch (IOException e) {
			//            throwWriteException(e);
		}
	}

	private static void throwReadException(Throwable t) throws CoreException {
		PHPeclipsePlugin.log(t);
		//		IStatus status= new JavaUIStatus(JavaStatusConstants.TEMPLATE_IO_EXCEPTION,
		//			ObfuscatorMessages.getString("TemplateSet.error.read"), t); //$NON-NLS-1$
		//		throw new JavaUIException(status);
	}

	private static void throwWriteException(Throwable t) throws CoreException {
		PHPeclipsePlugin.log(t);
		//		IStatus status= new JavaUIStatus(JavaStatusConstants.TEMPLATE_IO_EXCEPTION,
		//			ObfuscatorMessages.getString("TemplateSet.error.write"), t); //$NON-NLS-1$
		//		throw new JavaUIException(status);
	}

}