package pt.ist.renderers;

import java.io.IOException;
import java.io.UnsupportedEncodingException;

import org.apache.commons.beanutils.PropertyUtils;

import pt.ist.renderers.components.HtmlComponent;
import pt.ist.renderers.components.HtmlForm;
import pt.ist.renderers.components.HtmlInputFile;
import pt.ist.renderers.components.HtmlSimpleValueComponent;
import pt.ist.renderers.components.controllers.HtmlController;
import pt.ist.renderers.components.converters.ConversionException;
import pt.ist.renderers.components.converters.Converter;
import pt.ist.renderers.components.state.IViewState;
import pt.ist.renderers.layouts.Layout;
import pt.ist.renderers.model.MetaObject;
import pt.ist.renderers.model.MetaSlot;
import pt.ist.renderers.model.MetaSlotKey;
import pt.ist.renderers.plugin.RenderersRequestProcessorImpl;
import pt.ist.renderers.servlets.commons.UploadedFile;

/**
 * This renderer creates a file input field that allows the user to submit a
 * file. The renderer will set the slot with an output stream that represents
 * the file.
 * 
 * <p>
 * Example: <input type="file"/>
 * 
 * @author cfgi
 */
public class FileInputRenderer extends InputRenderer {

    private String size;
    private String fileNameSlot;
    private String fileSizeSlot;
    private String fileContentTypeSlot;

    public String getSize() {
	return this.size;
    }

    /**
     * Selects the size of the file input field.
     * 
     * @property
     */
    public void setSize(String size) {
	this.size = size;
    }

    public String getFileContentTypeSlot() {
	return this.fileContentTypeSlot;
    }

    /**
     * When this property is specified the renderer will set the given slot with
     * the content type of the file. The slot must have the string type.
     * 
     * @property
     */
    public void setFileContentTypeSlot(String fileContentTypeSlot) {
	this.fileContentTypeSlot = fileContentTypeSlot;
    }

    public String getFileNameSlot() {
	return this.fileNameSlot;
    }

    /**
     * When this property is specified the renderer will set the given slot with
     * the name of the file as given by the user. The slot must have the string
     * type.
     * 
     * @property
     */
    public void setFileNameSlot(String fileNameSlot) {
	this.fileNameSlot = fileNameSlot;
    }

    public String getFileSizeSlot() {
	return this.fileSizeSlot;
    }

    /**
     * When this property is specified the renderer will set the given slot with
     * the size of the file in bytes. The slot must be have the
     * <code>long</code> type.
     * 
     * @property
     */
    public void setFileSizeSlot(String fileSizeSlot) {
	this.fileSizeSlot = fileSizeSlot;
    }

    @Override
    protected Layout getLayout(Object object, Class type) {
	return new Layout() {

	    @Override
	    public HtmlComponent createComponent(Object object, Class type) {
		getInputContext().getForm().setEncoding(HtmlForm.FORM_DATA);

		HtmlInputFile file = new HtmlInputFile();
		file.setTargetSlot((MetaSlotKey) getInputContext().getMetaObject().getKey());

		file.setController(new UpdateFilePropertiesController(((MetaSlot) getInputContext().getMetaObject())
			.getMetaObject(), getFileNameSlot(), getFileSizeSlot(), getFileContentTypeSlot()));
		file.setConverter(new FileConverter(file));
		return file;
	    }

	    @Override
	    public void applyStyle(HtmlComponent component) {
		super.applyStyle(component);

		((HtmlInputFile) component).setSize(getSize());
	    }

	};
    }

    private static class UpdateFilePropertiesController extends HtmlController {

	private MetaObject object;
	private String fileNameSlot;
	private String fileSizeSlot;
	private String fileContentTypeSlot;

	public UpdateFilePropertiesController(MetaObject object, String fileNameSlot, String fileSizeSlot,
		String fileContentTypeSlot) {
	    this.object = object;
	    this.fileNameSlot = fileNameSlot;
	    this.fileSizeSlot = fileSizeSlot;
	    this.fileContentTypeSlot = fileContentTypeSlot;
	}

	@Override
	public void execute(IViewState viewState) {
	    HtmlSimpleValueComponent component = (HtmlSimpleValueComponent) getControlledComponent();
	    String name = component.getName();

	    UploadedFile file = RenderersRequestProcessorImpl.getUploadedFile(name);
	    if (file != null) { // if has file
		Object object = this.object.getObject();

		try {
		    String currentEncoding = RenderersRequestProcessorImpl.getCurrentEncoding();
		    setPropertyIgnoringErrors(object, this.fileNameSlot, currentEncoding != null ? new String(file.getName()
			    .getBytes(), currentEncoding) : new String(file.getName().getBytes()));
		} catch (UnsupportedEncodingException e) {
		    // best effort name setting
		    setPropertyIgnoringErrors(object, this.fileNameSlot, file.getName());
		    e.printStackTrace();
		}
		setPropertyIgnoringErrors(object, this.fileSizeSlot, file.getSize());
		setPropertyIgnoringErrors(object, this.fileContentTypeSlot, file.getContentType());
	    }
	}

	private void setPropertyIgnoringErrors(Object object, String property, Object value) {
	    if (property == null) {
		return;
	    }

	    try {
		PropertyUtils.setProperty(object, property, value);
	    } catch (Exception e) {
		e.printStackTrace();
	    }
	}
    }

    private static class FileConverter extends Converter {

	private HtmlInputFile component;

	public FileConverter(HtmlInputFile file) {
	    this.component = file;
	}

	@Override
	public Object convert(Class type, Object value) {
	    String name = this.component.getName();
	    UploadedFile file = RenderersRequestProcessorImpl.getUploadedFile(name);

	    if (file == null) {
		return null;
	    } else {
		try {
		    return file.getInputStream();
		} catch (IOException e) {
		    throw new ConversionException("renderers.converter.file.obtain", e, true, (Object[]) null);
		}
	    }
	}

    }
}