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.Vector;

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

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.xml.sax.InputSource;
import org.xml.sax.SAXException;

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;

/**
 * <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";
  private static final String KEYWORD_ATTR = "keyword";
  private static final String TYPE_ATTR = "type";
  private static final String CONSTANT_ATTR = "constant";
  private static final String FN_ATTR = "function";
  private static final String DESCRIPTION = "description";
  private static final String USAGE_ATTR = "usage";
  private static final String TOKENVAL_ATTR = "tokenval";
  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 Vector userdefsyntaxdata;

  private static Vector syntaxdata;

  public PHPSyntaxRdr() {
    syntaxdata = new Vector();
    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;
    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 Description = getAttributeValue(attributes, DESCRIPTION);
        String Usage = getAttributeValue(attributes, USAGE_ATTR);
        String Tokenval = getAttributeValue(attributes, TOKENVAL_ATTR);

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

  public static Vector getsyntaxdata() {
    return (Vector) syntaxdata.clone();
  }

  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 Vector getUserDefinitions() {
    return (Vector) userdefsyntaxdata.clone();
  }

  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(DESCRIPTION);
        description.setValue(((PHPElement) bufferobj).getDescription());
        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);
          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,
    //			TemplateMessages.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,
    //			TemplateMessages.getString("TemplateSet.error.write"), t); //$NON-NLS-1$
    //		throw new JavaUIException(status);
  }

}