package com.onaro.sanscreen.client.view.tabular.columns;

import java.beans.PropertyDescriptor;
import java.text.MessageFormat;
import java.util.List;

import org.apache.commons.lang3.StringUtils;
import org.eclipse.core.runtime.IAdaptable;

import com.onaro.commons.beans.BeanUtils;

/**
 * Variation on the {@link PropertyColumnValueRetriever} which reads an additional property
 * from the bean instance to use as the identifier for the property value.
 *
 * @param <B> the type of the bean objects to retrieve the property values from
 * @param <V> the type of the property value
 */
public class IdentifierPropertyColumnValueRetriever<B, V> extends PropertyColumnValueRetriever<B, V> {

    protected final List<PropertyDescriptor> identifierPropertyDescriptors;
    
    /**
     * Create a retriever which reads the value from a property
     * @param beanClass
     * @param propertyPath
     * @param identifierPropertyPath
     */
    public IdentifierPropertyColumnValueRetriever(Class<B> beanClass, String propertyPath, String identifierPropertyPath) {
        super(beanClass, propertyPath);
        
        if (StringUtils.isBlank(identifierPropertyPath) || !BeanUtils.hasPropertyPath(beanClass, identifierPropertyPath)) {
            throw new IllegalArgumentException(
                    MessageFormat.format("Identifier Property path ''{0}'' not valid for class ''{1}''",  //$NON-NLS-1$
                            identifierPropertyPath, beanClass.getName()));
        }
        
        this.identifierPropertyDescriptors = BeanUtils.getPropertyDescriptorsByPath(beanClass, identifierPropertyPath);
    }
    
    @Override
    public String getIdentifier(IAdaptable rowObj) {
        B bean = getBean(rowObj);
        
        Object propertyObj = BeanUtils.getPropertyValueByPath(identifierPropertyDescriptors, bean);
        if (propertyObj == null) {
            return null;
        }
        
        return propertyObj.toString();
    }
}