/**
 * <copyright> Copyright (c) 2006 by Know-Center, Graz, Austria </copyright>
 * 
 * This software is the confidential and proprietary information of Know-Center,
 * Graz, Austria. You shall not disclose such Confidential Information and shall
 * use it only in accordance with the terms of the license agreement you entered
 * into with Know-Center.
 * 
 * KNOW-CENTER MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
 * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR
 * NON-INFRINGEMENT. KNOW-CENTER SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY
 * LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES.
 * 
 * $Id: FoundBlock.java,v 1.2 2006/10/31 08:07:29 wprinz Exp $
 */
package at.knowcenter.wag.egov.egiz.framework;

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

import at.knowcenter.wag.egov.egiz.sig.SignatureTypeDefinition;
import at.knowcenter.wag.egov.egiz.sig.SignatureTypes;

/**
 * Contains all the information about a found Block in text extracton.
 * 
 * <p>
 * This is basically the ordered list of found captions.
 * </p>
 * 
 * @author wprinz
 */
public class FoundBlock
{
  /**
   * The ordered list of found keys.
   */
  public List found_keys = null;

  /**
   * The end index of the block.
   */
  public int end_index = 0;

  /**
   * The type of the block.
   */
  public SignatureTypeDefinition std = null;

  /**
   * Returns the first key of this block.
   * 
   * @return Returns the first key of this block.
   */
  public FoundKey getFirstKey()
  {
    return (FoundKey) this.found_keys.get(found_keys.size() - 1);
  }

  /**
   * Returns the last key of this block.
   * 
   * @return Returns the last key of this block.
   */
  public FoundKey getLastKey()
  {
    return (FoundKey) this.found_keys.get(0);
  }

  /**
   * Returns the size of this block.
   * 
   * <p>
   * Note that this doesn't give the exact size of the block, but rather a value
   * suirable for comparison.
   * </p>
   * 
   * @return Returns the size of this block.
   */
  public int getSize()
  {
    int size = getLastKey().start_index - getFirstKey().start_index;
    return size;
  }

  /**
   * @see java.lang.Object#toString()
   */
  public String toString()
  {
    return "FoundBlock: std=" + this.std.getType() + ", #=" + this.found_keys.size() + ", size = " + getSize();
  }

  /**
   * Tells, if this block is semantically equal to the other block.
   * 
   * Two blocks are semantically equal, if all the required have the
   * same captions in the same order.
   * 
   * @param other_block
   *          The other block.
   * @return Returns true, of this block is semantically equal to the other one,
   *         false otherwise.
   */
  public boolean isSemanticallyEqual(FoundBlock other_block)
  {
    List this_keys = filterOutNonRequiredFoundKeys(this.found_keys);
    List other_keys = filterOutNonRequiredFoundKeys(other_block.found_keys);
    
    if (this_keys.size() != other_keys.size())
    {
      return false;
    }

    for (int i = 0; i < this_keys.size(); i++)
    {
      FoundKey this_found_key = (FoundKey) this_keys.get(i);
      FoundKey other_found_key = (FoundKey) other_keys.get(i);

      if (!this_found_key.isSemanticallyEqual(other_found_key))
      {
        return false;
      }
    }
    return true;
  }
  
  /**
   * Filters out all non required keys from the List of found keys.
   * 
   * @param found_keys The List of found keys.
   * 
   * @return Rturns the subset List which contains only the required keys.
   */
  protected static List filterOutNonRequiredFoundKeys (List found_keys)
  {
    List required_found_keys = new ArrayList(found_keys.size());
    for (int i = 0; i < found_keys.size(); i++)
    {
      FoundKey this_found_key = (FoundKey) found_keys.get(i);

      if (!SignatureTypes.isRequiredKey(this_found_key.key))
      {
        continue;
      }
      
      required_found_keys.add(this_found_key);
    }
    return required_found_keys;
  }

  /**
   * Tells, if this block is strictly semantically equal to the other block.
   * 
   * Two blocks are strictly semantically equal, if they contain the same keys with the
   * same captions in the same order.
   * 
   * @param other_block
   *          The other block.
   * @return Returns true, of this block is semantically equal to the other one,
   *         false otherwise.
   */
  public boolean isStrictlySemanticallyEqual(FoundBlock other_block)
  {
    if (this.found_keys.size() != other_block.found_keys.size())
    {
      return false;
    }

    for (int i = 0; i < this.found_keys.size(); i++)
    {
      FoundKey this_found_key = (FoundKey) this.found_keys.get(i);
      FoundKey other_found_key = (FoundKey) other_block.found_keys.get(i);

      if (!this_found_key.isSemanticallyEqual(other_found_key))
      {
        return false;
      }
    }
    return true;
  }
  
  
  public FoundKey getDateFoundKey ()
  {
    for (int i = 0; i < this.found_keys.size(); i++)
    {
      FoundKey found_key = (FoundKey) this.found_keys.get(i);
      if (found_key.key.equals(SignatureTypes.SIG_DATE))
      {
        return found_key;
      }
    }
    throw new RuntimeException("There is no SIG_DATE in the list of found_keys. This must not happen.");
  }
}