/*
 * Copyright 2004 Chris Nelson
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and limitations under the License.
 */
package org.trails.component;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import ognl.Ognl;
import ognl.OgnlException;

import org.apache.tapestry.IAsset;
import org.apache.tapestry.annotations.ComponentClass;
import org.apache.tapestry.annotations.InjectObject;
import org.apache.tapestry.annotations.Parameter;
import org.apache.tapestry.services.ExpressionEvaluator;
import org.apache.tapestry.util.ComponentAddress;
import org.trails.component.blob.BlobDownloadService;
import org.trails.component.blob.ITrailsBlob;
import org.trails.component.blob.TrailsBlobAsset;
import org.trails.descriptor.BlobDescriptorExtension;
import org.trails.descriptor.DescriptorService;
import org.trails.descriptor.IPropertyDescriptor;
import org.trails.persistence.PersistenceService;

/**
 * Produces a table for the list of instances
 */
@ComponentClass(allowBody = true, allowInformalParameters = true)
public abstract class ObjectTable extends ClassDescriptorComponent
{
	public static final String LINK_COLUMN = "linkColumnValue";

	@Parameter(required = false, defaultValue = "false", cache = true)
	public abstract boolean isShowCollections();

	public abstract void setShowCollections(boolean ShowCollections);

	@InjectObject("spring:persistenceService")
	public abstract PersistenceService getPersistenceService();

	@Parameter
	public abstract List getInstances();

	public abstract void setInstances(List instances);

	public abstract Object getCurrentObject();

	public abstract void setCurrentObject(Object currentObject);

	@Parameter(cache = false, defaultValue = "currentObject")
	public abstract Object getObject();

	public abstract void setObject(Object object);

	@Parameter(cache = false)
	public abstract String getRowsClass();

	public abstract void setRowsClass(String rowsClass);

	@Parameter(cache = false, defaultValue = "10")
	public abstract int getPageSize();

	public abstract void setPageSize(int rowsClass);

	public ComponentAddress getLinkBlockAddress(IPropertyDescriptor descriptor)
	{
		if (getBlockAddress(descriptor) != null)
		{
			return getBlockAddress(descriptor);
		} else
		{
			return new ComponentAddress(getComponent(LINK_COLUMN));
		}
	}

	@InjectObject("service:tapestry.ognl.ExpressionEvaluator")
	public abstract ExpressionEvaluator getEvaluator();

	/**
	 * @return
	 */
	public List<TrailsTableColumn> getColumns()
	{
		ArrayList<TrailsTableColumn> columns = new ArrayList<TrailsTableColumn>();
		for (Iterator iter = getPropertyDescriptors().iterator(); iter.hasNext();)
		{
			IPropertyDescriptor descriptor = (IPropertyDescriptor) iter.next();
			if (displaying(descriptor))
			{
				if (getLinkProperty().equals(descriptor.getName())
						&& (getClassDescriptor().isAllowSave() || getClassDescriptor().isAllowRemove()))
				{
					/**
					 * Add a link for the edit page following these rules: a)
					 * Use the identifier descriptor if is displayable (
					 * summary=true ). b) Use the first displayable property if
					 * the identifier property is not displayable
					 * (summary=false)
					 */
					columns.add(new TrailsTableColumn(descriptor, getEvaluator(), getLinkBlockAddress(descriptor)));

				} else
				{
					columns.add(new TrailsTableColumn(descriptor, getEvaluator(), getBlockAddress(descriptor)));
				}

			}
		}

		return columns;
	}

	/**
	 * @param descriptor
	 * @return
	 */
	private boolean displaying(IPropertyDescriptor descriptor)
	{
		if (descriptor.isHidden() || !descriptor.isSummary())
		{
			return false;
		} else if ((descriptor.isCollection() && isShowCollections()) || (!descriptor.isCollection()))
		{
			return true;
		} else
		{
			return false;
		}

	}

	/**
	 * @return
	 */
	public String getIdentifierProperty()
	{
		return this.getIdentifierPropertyDescriptor().getName();

	}

	/**
	 * Returns the name of the property to be used as link to the editor. If the
	 * default Id property is not displayable then return the name of the first
	 * displayable property.
	 * 
	 * @return
	 */
	public String getLinkProperty()
	{
		IPropertyDescriptor propertyDescriptor = this.getIdentifierPropertyDescriptor();
		if (!this.displaying(propertyDescriptor))
			propertyDescriptor = this.getFirstDisplayableProperty();

		return propertyDescriptor.getName();
	}
	/**
	 * Returns the first displayable property.
	 * 
	 * @return
	 */
	protected IPropertyDescriptor getFirstDisplayableProperty()
	{
		for (Iterator iter = getPropertyDescriptors().iterator(); iter.hasNext();)
		{
			IPropertyDescriptor descriptor = (IPropertyDescriptor) iter.next();
			if (displaying(descriptor))
			{
				return descriptor;

			}
		}

		return null; // If we get here, that means we have no displayable
		// descriptors
		// TODO check if we should throw an exception instead
	}

	/**
	 * @return
	 */
	protected IPropertyDescriptor getIdentifierPropertyDescriptor()
	{
		return (IPropertyDescriptor) getClassDescriptor().getIdentifierDescriptor();

	}

	public ComponentAddress getBlockAddress(IPropertyDescriptor descriptor)
	{
		String blockName = descriptor.getName() + "ColumnValue";
		if (getPage().getComponents().containsKey(blockName))
		{
			return new ComponentAddress(getPage().getPageName(), blockName);
		} else
			return null;
	}

	public Object getSource()
	{
		return getInstances();
	}

	@InjectObject("spring:descriptorService")
	public abstract DescriptorService getDescriptorService();

	@InjectObject("service:trails.BlobService")
	public abstract BlobDownloadService getDownloadService();

	public BlobDescriptorExtension getBlobDescriptorExtension()
	{
		return getPhotoColumnPropertyDescriptor().getExtension(BlobDescriptorExtension.class);
	}

	public IAsset getByteArrayAsset()
	{
		IPropertyDescriptor idDescriptor = getDescriptorService().getClassDescriptor(getPhotoColumnPropertyDescriptor().getBeanType()).getIdentifierDescriptor();

		/**
		 * get the ID
		 */
		String id = "";
		try
		{
			if (Ognl.getValue(idDescriptor.getName(), getObject()) != null)
				id = Ognl.getValue(idDescriptor.getName(),
						getObject()).toString();
		} catch (OgnlException e)
		{
			e.printStackTrace();
		}

		/**
		 * get the blob
		 */
		ITrailsBlob trailsBlob = null;
		try
		{
			if (Ognl.getValue(getPhotoColumnPropertyDescriptor().getName(), getObject()) != null)
			{
				trailsBlob = (ITrailsBlob) Ognl.getValue(getPhotoColumnPropertyDescriptor().getName(), getObject());
			}
		} catch (OgnlException e)
		{
			e.printStackTrace();
		}

		return new TrailsBlobAsset(getDownloadService(),
				getClassDescriptor().getType().getName(),
				id,
				getPhotoColumnPropertyDescriptor().getName(),
				trailsBlob.getContentType(),
				trailsBlob.getFileName());
	}

	public IPropertyDescriptor getPhotoColumnPropertyDescriptor()
	{
		IPropertyDescriptor result = null;

		for (Iterator iter = getPropertyDescriptors().iterator(); iter.hasNext();)
		{
			IPropertyDescriptor descriptor = (IPropertyDescriptor) iter.next();
			if (displaying(descriptor) && descriptor.getName().equalsIgnoreCase("photo"))
			{
				if (descriptor.supportsExtension(org.trails.descriptor.BlobDescriptorExtension.class.getName()))
				{
					result = descriptor;
					break;
				}
			}
		}
		return result;
	}
}