package pt.utl.ist.fenix.tools.file;

import java.io.PrintWriter;
import java.io.Serializable;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.tree.BaseElement;

import pt.linkare.scorm.utils.ScormMetaData;

/**
 * This class is an abstraction around the concept of metadata
 * It clearly uses the Dublin Core approach to MetaData which will
 * be enough for now
 * @author José Pedro Pereira - Linkare TI
 *
 */
@SuppressWarnings("serial")
public class FileSetMetaData implements Serializable,XMLSerializable{

	/**
	 * Dublin Core qualification "element"
	 */
	private String element = null;

	/**
	 * Dublin Core qualification "qualifier" 
	 */
	private String qualifier = null;
	
	/**
	 * Dublin Core qualification "lang"
	 */
	private String lang = null;

	/**
	 * Dublin Core qualification "values"
	 */
	private String[] values = null;

	/**
	 * 
	 * @param element The Dublin Core element
	 * @param qualifier The Dublin Core qualifier
	 * @param lang The Language
	 * @param values The array of values
	 */
	public FileSetMetaData(String element, String qualifier, String lang, String[] values) {
		this.element = element;
		this.qualifier = qualifier;
		this.lang = lang;
		this.values = values;
	}

	/**
	 * Shortcut constructor @see FileSetMetaData#FileSetMetaData(String, String, String, String[])
	 * @param element
	 * @param qualifier
	 * @param lang
	 * @param value
	 */
	public FileSetMetaData(String element, String qualifier, String lang, String value) {
		this.element = element;
		this.qualifier = qualifier;
		this.lang = lang;
		this.values = new String[] { value };
	}

	/**
	 * default public constructor for serialization
	 */ 
	public FileSetMetaData() {

	}

	/**
	 * @return Returns the element.
	 */
	public String getElement() {
		return element;
	}

	/**
	 * @param element
	 *            The element to set.
	 */
	public void setElement(String element) {
		this.element = element;
	}

	/**
	 * @return Returns the lang.
	 */
	public String getLang() {
		return lang;
	}

	/**
	 * @param lang
	 *            The lang to set.
	 */
	public void setLang(String lang) {
		this.lang = lang;
	}

	/**
	 * @return Returns the qualifier.
	 */
	public String getQualifier() {
		return qualifier;
	}

	/**
	 * @param qualifier
	 *            The qualifier to set.
	 */
	public void setQualifier(String qualifier) {
		this.qualifier = qualifier;
	}

	/**
	 * @return Returns the values.
	 */
	public String[] getValues() {
		return values;
	}

	/**
	 * @param values
	 *            The values to set.
	 */
	public void setValues(String[] values) {
		this.values = values;
	}

	// TODO Verificr se este n dá erro!!
	public void setValue(String value) {
		Collection<String> colstr = new ArrayList<String>(1);
		colstr.add(value);
		this.values = (String[]) colstr.toArray(new String[0]);
	}

	public static void print(PrintWriter out, Collection<FileSetMetaData> colItemMetadata) {
		int colIndex = 0;
		if (colItemMetadata != null && colItemMetadata.size() > 0) {
			for (FileSetMetaData itemMeta : colItemMetadata) {
				out.println("Metadata[" + (colIndex++) + "] :");
				itemMeta.print(out);
			}
		}
		else out.println("No FileSet Metadata in collection");
	}

	private void print(PrintWriter out) {
		out.print("Element: " + this.getElement());
		out.print(" Qualifier: " + this.getQualifier());
		out.println(" Language: " + this.getLang());
		String[] valueArray = this.getValues();
		int arrayIndex = 0;
		if (valueArray != null) {
			for (String value : valueArray) {
				out.println("   Value[" + (arrayIndex++) + "]: " + value);
			}
		}
		else out.println("   No value defined");
	}

	public String toString() {
		StringWriter sw = new StringWriter();
		PrintWriter pw = new PrintWriter(sw);

		print(pw);

		pw.flush();
		String retVal = sw.getBuffer().toString();
		pw.close();

		return retVal;
	}
	
	/**
	 * Factory method for commonly used "author" metainfo
	 * 
	 * @param name The name of the author
	 * @return A FileSetMetaData correctly specified for DublinCore classification
	 */
	public static FileSetMetaData createAuthorMeta(String name)
	{
		return new FileSetMetaData("contributor","author",null,name);
	}

	/**
	 * Factory method for commonly used "author" metainfo
	 * 
	 * @param lang The language for the authorship
	 * @param name The name of the author
	 * @return A FileSetMetaData correctly specified for DublinCore classification
	 */
	public static FileSetMetaData createAuthorMeta(String lang,String name)
	{
		return new FileSetMetaData("contributor","author",lang,name);
	}

	/**
	 * Factory method for commonly used "title" metainfo
	 * 
	 * @param lang The language for the authorship
	 * @param title The title for the content
	 * @return A FileSetMetaData correctly specified for DublinCore classification
	 */
	public static FileSetMetaData createTitleMeta(String lang,String title)
	{
		return new FileSetMetaData("title",null,lang,title);
	}

	
	/**
	 * Factory method for commonly used "title" metainfo
	 * 
	 * @param title The title for the content
	 * @return A FileSetMetaData correctly specified for DublinCore classification
	 */
	public static FileSetMetaData createTitleMeta(String title)
	{
		return new FileSetMetaData("title",null,null,title);
	}

	public static FileSetMetaData createWidthMeta(int width)
	{
		return new FileSetMetaData("width",null,null,""+width);
	}

	public static FileSetMetaData createHeightMeta(int height)
	{
		return new FileSetMetaData("height",null,null,""+height);
	}

	public static FileSetMetaData[] createWidthHeightMeta(int width,int height)
	{
		return new FileSetMetaData[]{createWidthMeta(width),createHeightMeta(height)};
	}

	
	
	public static Collection<FileSetMetaData> createFileSetMetaDatasFromScormMetaDatas(Collection<ScormMetaData> scormMetaDatas)
	{
		if(scormMetaDatas==null) 
			return null;
		ArrayList<FileSetMetaData> retVal=new ArrayList<FileSetMetaData>(scormMetaDatas.size());
		for(ScormMetaData current:scormMetaDatas)
		{
			retVal.add(createFileSetMetaDataFromScormMetaData(current));
		}
		return retVal;
	}
	
	public static FileSetMetaData createFileSetMetaDataFromScormMetaData(ScormMetaData scormMetaData)
	{
		if(scormMetaData==null)
			return null;
		
		return new FileSetMetaData(scormMetaData.getElement(),scormMetaData.getQualifier(),scormMetaData.getLang(),scormMetaData.getValues());
	}

    /** Auto generated javadoc
     * 
     * @see pt.utl.ist.fenix.tools.file.XMLSerializable#toXMLString()
     */
    public String toXMLString() {
        return toXML().asXML();
    }
    
    public Element toXML()
    {
        Element xmlElement=new BaseElement("filesetmetadata");
        if(getElement()!=null)
        {
            Element elementElement=xmlElement.addElement("element");
            elementElement.setText(getElement());
        }
        if(getQualifier()!=null)
        {
            Element qualifierElement=xmlElement.addElement("qualifier");
            qualifierElement.setText(getQualifier());
        }
        if(getLang()!=null)
        {
            Element langElement=xmlElement.addElement("lang");
            langElement.setText(getLang());
        }
        if(getValues()!=null)
        {
            Element valuesElement=xmlElement.addElement("values");
            int count=0;
            for(String value:getValues())
            {
                if(value!=null) {
                	Element valueElement=valuesElement.addElement("value"+count++);
                	valueElement.setText(value);
                }
            }
        }
        return xmlElement;
    }
    
    @SuppressWarnings("unchecked")
    public void fromXML(Element elem)
    {
        Element elementElement=elem.element("element");
        if(elementElement!=null)
        {
            this.setElement((String)elementElement.getText());
        }
        Element qualifierElement=elem.element("qualifier");
        if(qualifierElement!=null)
        {
            this.setQualifier((String)qualifierElement.getText());
        }
        Element langElement=elem.element("lang");
        if(langElement!=null)
        {
            this.setLang((String)langElement.getText());
        }
        Element valuesElement=elem.element("values");
        if(valuesElement!=null)
        {
            List<Element> valueElements=(List<Element>)valuesElement.elements();
            String[] valuesAux=new String[valueElements.size()];
            int count=0;
            for(Element valueElement:valueElements)
            {
                valuesAux[count++]=(String)valueElement.getText();
            }
            this.setValues(valuesAux);
        }

    }

    /** Auto generated javadoc
     * 
     * @see pt.utl.ist.fenix.tools.file.XMLSerializable#fromXMLString(java.lang.String)
     */    
    public void fromXMLString(String xml) {
        try {
            fromXML(DocumentHelper.parseText(xml).getRootElement());
        }
        catch (DocumentException e) {
            throw new RuntimeException("Error parsing xml string : "+xml,e);
        }
    }

    public static FileSetMetaData buildFromXMLString(String xmlString) {
        FileSetMetaData metadata = new FileSetMetaData();
        metadata.fromXMLString(xmlString);
        return metadata;
    }
}