/*
 * JBoss, the OpenSource J2EE webOS
 *
 * Distributable under LGPL license.
 * See terms of license at gnu.org.
 */
package org.jboss.ejb.plugins.cmp.jdbc2.bridge;

import org.jboss.ejb.plugins.cmp.bridge.CMPFieldBridge;
import org.jboss.ejb.plugins.cmp.jdbc2.JDBCStoreManager2;
import org.jboss.ejb.plugins.cmp.jdbc2.PersistentContext;
import org.jboss.ejb.plugins.cmp.jdbc.metadata.JDBCCMPFieldMetaData;
import org.jboss.ejb.plugins.cmp.jdbc.JDBCType;
import org.jboss.ejb.plugins.cmp.jdbc.JDBCEntityPersistenceStore;
import org.jboss.ejb.plugins.cmp.jdbc.JDBCResultSetReader;
import org.jboss.ejb.plugins.cmp.jdbc.bridge.JDBCFieldBridge;
import org.jboss.ejb.EntityEnterpriseContext;
import org.jboss.deployment.DeploymentException;
import org.jboss.logging.Logger;

import javax.ejb.EJBException;
import java.lang.reflect.Field;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.ResultSet;

/**
 * @author <a href="mailto:alex@jboss.org">Alexey Loubyansky</a>
 * @version <tt>$Revision: 1.3 $</tt>
 */
public class JDBCCMPFieldBridge2
   implements CMPFieldBridge, JDBCFieldBridge
{
   private final JDBCEntityBridge2 entity;
   private final int rowIndex;
   private final JDBCType jdbcType;
   private final Class pkClass;
   private final Field pkField;
   private final boolean isPrimaryKeyMember;
   private final String fieldName;
   private final Class fieldType;
   private final String columnName;

   private final JDBCCMPFieldBridge2 cmpFieldIAmMappedTo;

   private final Logger log;

   private int versionIndex = -1;

   public JDBCCMPFieldBridge2(JDBCStoreManager2 manager,
                              JDBCEntityBridge2 entity,
                              JDBCCMPFieldMetaData metadata,
                              int rowIndex)
      throws DeploymentException
   {
      this.rowIndex = rowIndex;
      this.entity = entity;
      jdbcType = manager.getJDBCTypeFactory().getJDBCType(metadata);
      pkClass = metadata.getEntity().getPrimaryKeyClass();
      pkField = metadata.getPrimaryKeyField();
      isPrimaryKeyMember = metadata.isPrimaryKeyMember();
      fieldName = metadata.getFieldName();
      fieldType = metadata.getFieldType();
      cmpFieldIAmMappedTo = null;
      columnName = metadata.getColumnName();

      log = Logger.getLogger(this.getClass().getName() + "." + entity.getEntityName() + "#" + getFieldName());
   }

   public JDBCCMPFieldBridge2(JDBCCMPFieldBridge2 cmpField, JDBCCMPFieldBridge2 relatedPKField)
   {
      entity = cmpField.entity;
      rowIndex = cmpField.rowIndex;
      jdbcType = cmpField.jdbcType;
      columnName = cmpField.columnName;

      fieldName = relatedPKField.fieldName;
      fieldType = relatedPKField.fieldType;
      pkClass = relatedPKField.pkClass;
      pkField = relatedPKField.pkField;

      isPrimaryKeyMember = false;

      cmpFieldIAmMappedTo = cmpField;

      log = Logger.getLogger(this.getClass().getName() + "." + entity.getEntityName() + "#" + getFieldName());
   }

   // Public

   public void initVersion()
   {
      versionIndex = entity.getTable().addVersionField();
   }

   public int getVersionIndex()
   {
      return versionIndex;
   }
   
   public String getColumnName()
   {
      return columnName;
   }

   public Object setPrimaryKeyValue(Object primaryKey, Object value)
      throws IllegalArgumentException
   {
      try
      {
         if(pkField != null)
         {
            // if we are trying to set a null value into a null pk, we are already done.
            if(value == null && primaryKey == null)
            {
               return null;
            }

            // if we don't have a pk object yet create one
            if(primaryKey == null)
            {
               primaryKey = pkClass.newInstance();
            }

            // Set this field's value into the primary key object.
            pkField.set(primaryKey, value);
            return primaryKey;
         }
         else
         {
            // This field is the primary key, so no extraction is necessary.
            return value;
         }
      }
      catch(Exception e)
      {
         // Non recoverable internal exception
         throw new EJBException("Internal error setting instance field " + getFieldName(), e);
      }
   }

   public void setValueInternal(EntityEnterpriseContext ctx, Object value, boolean makeDirty)
   {
      PersistentContext pctx = (PersistentContext) ctx.getPersistenceContext();

      // todo this is weird
      if(cmpFieldIAmMappedTo != null && cmpFieldIAmMappedTo.isPrimaryKeyMember)
      {
         Object curValue = pctx.getFieldValue(rowIndex);
         if(value != null && !value.equals(curValue))
         {
            throw new IllegalStateException(
               "Attempt to modify a primary key field through a foreign key field mapped to it: "
               +
               entity.getEntityName()
               + "."
               + cmpFieldIAmMappedTo.getFieldName()
               +
               " -> "
               + entity.getQualifiedTableName()
               + "."
               + cmpFieldIAmMappedTo.getColumnName() +
               ", current value=" + curValue + ", new value=" + value
            );
         }

         makeDirty = false;
      }
      else
      {
         pctx.setFieldValue(rowIndex, value);
      }

      if(makeDirty)
      {
         pctx.setDirty();
      }
   }

   public int setArgumentParameters(PreparedStatement ps, int parameterIndex, Object arg)
   {
      try
      {
         int[] jdbcTypes = jdbcType.getJDBCTypes();
         for(int i = 0; i < jdbcTypes.length; i++)
         {
            Object columnValue = jdbcType.getColumnValue(i, arg);
            jdbcType.getParameterSetter()[i].set(ps, parameterIndex++, jdbcTypes[i], columnValue, log);
            //JDBCUtil.setParameter(log, ps, parameterIndex++, jdbcTypes[i], columnValue);
         }
         return parameterIndex;
      }
      catch(SQLException e)
      {
         // Non recoverable internal exception
         throw new EJBException("Internal error setting parameters for field " + getFieldName(), e);
      }
   }

   public Object loadArgumentResults(ResultSet rs, int parameterIndex)
      throws IllegalArgumentException
   {
      try
      {
         // update the value from the result set
         Class[] javaTypes = jdbcType.getJavaTypes();
         if(javaTypes.length > 1)
         {
            throw new IllegalStateException("Complex types are not supported yet.");
         }

         JDBCResultSetReader[] rsReaders = jdbcType.getResultSetReaders();

         Object columnValue = null;
         for(int i = 0; i < javaTypes.length; i++)
         {
            columnValue = rsReaders[i].get(rs, parameterIndex++, javaTypes[i], log);
            columnValue = jdbcType.setColumnValue(i, null, columnValue);
         }

         // retrun the updated parameterIndex
         return columnValue;
      }
      catch(SQLException e)
      {
         // Non recoverable internal exception
         throw new EJBException("Internal error getting results for field member " + getFieldName(), e);
      }
   }

   public int getRowIndex()
   {
      return rowIndex;
   }

   public JDBCEntityPersistenceStore getManager()
   {
      return entity.getManager();
   }

   // JDBCFieldBridge implementation

   public void initInstance(EntityEnterpriseContext ctx)
   {
      Object value;
      Class fieldType = getFieldType();
      if(fieldType == boolean.class)
      {
         value = Boolean.FALSE;
      }
      else if(fieldType == byte.class)
      {
         value = new Byte((byte) 0);
      }
      else if(fieldType == int.class)
      {
         value = new Integer(0);
      }
      else if(fieldType == long.class)
      {
         value = new Long(0L);
      }
      else if(fieldType == short.class)
      {
         value = new Short((short) 0);
      }
      else if(fieldType == char.class)
      {
         value = new Character('\u0000');
      }
      else if(fieldType == double.class)
      {
         value = new Double(0d);
      }
      else if(fieldType == float.class)
      {
         value = new Float(0f);
      }
      else
      {
         value = null;
      }
      setValueInternal(ctx, value, false);
   }

   public void resetPersistenceContext(EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public int setInstanceParameters(PreparedStatement ps, int parameterIndex, EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public Object getInstanceValue(EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public void setInstanceValue(EntityEnterpriseContext ctx, Object value)
   {
      throw new UnsupportedOperationException();
   }

   public int loadInstanceResults(ResultSet rs, int parameterIndex, EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public int loadArgumentResults(ResultSet rs, int parameterIndex, Object[] argumentRef)
   {
      throw new UnsupportedOperationException();
   }

   public boolean isDirty(EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public void setClean(EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public boolean isCMPField()
   {
      return true;
   }

   public boolean isPrimaryKeyMember()
   {
      return isPrimaryKeyMember;
   }

   public boolean isReadOnly()
   {
      throw new UnsupportedOperationException();
   }

   public boolean isReadTimedOut(EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public boolean isLoaded(EntityEnterpriseContext ctx)
   {
      throw new UnsupportedOperationException();
   }

   public JDBCType getJDBCType()
   {
      return jdbcType;
   }

   public Object getPrimaryKeyValue(Object primaryKey)
      throws IllegalArgumentException
   {
      try
      {
         if(pkField != null)
         {
            if(primaryKey == null)
            {
               return null;
            }

            return pkField.get(primaryKey);
         }
         else
         {
            return primaryKey;
         }
      }
      catch(Exception e)
      {
         throw new EJBException("Internal error getting primary key field member " + getFieldName(), e);
      }
   }

   // CMPFieldBridge implementation

   public String getFieldName()
   {
      return fieldName;
   }

   public Object getValue(EntityEnterpriseContext ctx)
   {
      PersistentContext pctx = (PersistentContext) ctx.getPersistenceContext();
      return pctx.getFieldValue(rowIndex);
   }

   public void setValue(EntityEnterpriseContext ctx, Object value)
   {
      setValueInternal(ctx, value, true);
   }

   public Class getFieldType()
   {
      return fieldType;
   }
}