/*
    * Copyright 2006-2007 the original author or authors.
    *
    * 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.springframework.batch.sample.domain.order.internal;
  
  import java.util.ArrayList;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.springframework.batch.item.ItemReader;
  import org.springframework.batch.item.file.mapping.FieldSetMapper;
  import org.springframework.batch.item.file.transform.FieldSet;
  import org.springframework.batch.sample.domain.order.Address;
  import org.springframework.batch.sample.domain.order.BillingInfo;
  import org.springframework.batch.sample.domain.order.Customer;
  import org.springframework.batch.sample.domain.order.LineItem;
  import org.springframework.batch.sample.domain.order.Order;
  import org.springframework.batch.sample.domain.order.ShippingInfo;
  
  /**
   * @author peter.zozom
   * 
   */
  public class OrderItemReader implements ItemReader<Order> {
  	private static Log log = LogFactory.getLog(OrderItemReader.class);
  
  	private Order order;
  
  	private boolean recordFinished;
  
  	private FieldSetMapper<Order> headerMapper;
  
  	private FieldSetMapper<Customer> customerMapper;
  
  	private FieldSetMapper<Address> addressMapper;
  
  	private FieldSetMapper<BillingInfo> billingMapper;
  
  	private FieldSetMapper<LineItem> itemMapper;
  
  	private FieldSetMapper<ShippingInfo> shippingMapper;
  
  	private ItemReader<FieldSet> fieldSetReader;
  
  	/**
  	 * @throws Exception
  	 * @see org.springframework.batch.item.ItemReader#read()
  	 */
  	public Order read() throws Exception {
  		recordFinished = false;
  
  		while (!recordFinished) {
  			process(fieldSetReader.read());
  		}
  
  		log.info("Mapped: " + order);
  
  		Order result = order;
  		order = null;
  
  		return result;
  	}
  
  	private void process(FieldSet fieldSet) throws Exception {
  		// finish processing if we hit the end of file
  		if (fieldSet == null) {
  			log.debug("FINISHED");
  			recordFinished = true;
  			order = null;
  			return;
  		}
  
  		String lineId = fieldSet.readString(0);
  
  		// start a new Order
  		if (Order.LINE_ID_HEADER.equals(lineId)) {
  			log.debug("STARTING NEW RECORD");
  			order = headerMapper.mapFieldSet(fieldSet);
  		}
  		else if (Order.LINE_ID_FOOTER.equals(lineId)) {
  			log.debug("END OF RECORD");
  
  			// Do mapping for footer here, because mapper does not allow to pass
  			// an Order object as input.
  			// Mapper always creates new object
  			order.setTotalPrice(fieldSet.readBigDecimal("TOTAL_PRICE"));
 			order.setTotalLines(fieldSet.readInt("TOTAL_LINE_ITEMS"));
 			order.setTotalItems(fieldSet.readInt("TOTAL_ITEMS"));
 
 			// mark we are finished with current Order
 			recordFinished = true;
 		}
 		else if (Customer.LINE_ID_BUSINESS_CUST.equals(lineId)) {
 			log.debug("MAPPING CUSTOMER");
 			if (order.getCustomer() == null) {
 				Customer customer = customerMapper.mapFieldSet(fieldSet);
 				customer.setBusinessCustomer(true);
 				order.setCustomer(customer);
 			}
 		}
 		else if (Customer.LINE_ID_NON_BUSINESS_CUST.equals(lineId)) {
 			log.debug("MAPPING CUSTOMER");
 			if (order.getCustomer() == null) {
 				Customer customer = customerMapper.mapFieldSet(fieldSet);
 				customer.setBusinessCustomer(false);
 				order.setCustomer(customer);
 			}
 		}
 		else if (Address.LINE_ID_BILLING_ADDR.equals(lineId)) {
 			log.debug("MAPPING BILLING ADDRESS");
 			order.setBillingAddress(addressMapper.mapFieldSet(fieldSet));
 		}
 		else if (Address.LINE_ID_SHIPPING_ADDR.equals(lineId)) {
 			log.debug("MAPPING SHIPPING ADDRESS");
 			order.setShippingAddress(addressMapper.mapFieldSet(fieldSet));
 		}
 		else if (BillingInfo.LINE_ID_BILLING_INFO.equals(lineId)) {
 			log.debug("MAPPING BILLING INFO");
 			order.setBilling(billingMapper.mapFieldSet(fieldSet));
 		}
 		else if (ShippingInfo.LINE_ID_SHIPPING_INFO.equals(lineId)) {
 			log.debug("MAPPING SHIPPING INFO");
 			order.setShipping(shippingMapper.mapFieldSet(fieldSet));
 		}
 		else if (LineItem.LINE_ID_ITEM.equals(lineId)) {
 			log.debug("MAPPING LINE ITEM");
 			if (order.getLineItems() == null) {
 				order.setLineItems(new ArrayList<LineItem>());
 			}
 			order.getLineItems().add(itemMapper.mapFieldSet(fieldSet));
 		}
 		else {
 			log.debug("Could not map LINE_ID=" + lineId);
 		}
 
 	}
 
 	/**
 	 * @param fieldSetReader reads lines from the file converting them to
 	 *        {@link FieldSet}.
 	 */
 	public void setFieldSetReader(ItemReader<FieldSet> fieldSetReader) {
 		this.fieldSetReader = fieldSetReader;
 	}
 
 	public void setAddressMapper(FieldSetMapper<Address> addressMapper) {
 		this.addressMapper = addressMapper;
 	}
 
 	public void setBillingMapper(FieldSetMapper<BillingInfo> billingMapper) {
 		this.billingMapper = billingMapper;
 	}
 
 	public void setCustomerMapper(FieldSetMapper<Customer> customerMapper) {
 		this.customerMapper = customerMapper;
 	}
 
 	public void setHeaderMapper(FieldSetMapper<Order> headerMapper) {
 		this.headerMapper = headerMapper;
 	}
 
 	public void setItemMapper(FieldSetMapper<LineItem> itemMapper) {
 		this.itemMapper = itemMapper;
 	}
 
 	public void setShippingMapper(FieldSetMapper<ShippingInfo> shippingMapper) {
 		this.shippingMapper = shippingMapper;
 	}
 
 }