source: trunk/gsdl3/src/java/org/greenstone/gsdl3/gs3build/metadata/METSStructure.java@ 6103

package org.greenstone.gsdl3.gs3build.metadata;

import java.io.PrintWriter;

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

import java.sql.SQLException;
import java.sql.ResultSet;

import org.greenstone.gsdl3.gs3build.doctypes.DocumentInterface;

import org.greenstone.gsdl3.gs3build.util.XMLTools;
import org.greenstone.gsdl3.gs3build.util.GS3SQLConnection;
import org.greenstone.gsdl3.gs3build.database.*;

public class METSStructure
{
  Map children;
  String ID;
  String label;
  String type;
  
  public METSStructure(String id, String label, String type)
  { this.children = new HashMap();
    this.ID       = id;
    this.label    = label;
    this.type     = type;
  }
  
  /**
   *  Get the identifer of this structure
   *
   *  @param <code>String</code> the identifier.
   */
  public String getID()
  { return this.ID;
  }

  /**
   *  Find all the divisions that match a given list of file group
   *  identifiers...
   *
   *  @param <code>List</code> the list of identifiers to find
   *  @param <code>List</code> the list into which to place any
   *         matching identifiers.
   */
  public void findDivisionsForFiles(List listOfFileIdentifiers, List resultList)
  { Iterator groups = this.children.values().iterator();
    while (groups.hasNext())
    { METSDivision group = (METSDivision) groups.next();

      group.findDivisionsForFiles(listOfFileIdentifiers, resultList);
    }    
  }

  /**
   *  Add a division directly underneath this structure.
   *
   *  @param <code>METSDivision</code> the division to add.
   */
  public void addDivision(METSDivision division)
  { this.children.put(division.getID(), division);
  }

  /**
   *  Add a division further into this structure.
   *
   *  @param <code>String</code> the identifier for the division
   *         within which the division is to be added.
   *  @param <code>METSDivision</code> the division to add.   
   */
  public void addSubDivision(String divisionID, METSDivision division)
  { String topDivision = METSDivision.getTopDivisionName(divisionID);

    METSDivision child = (METSDivision) this.children.get(topDivision);
    if (child == null)
    { return;
    }

    String subDivisionID = METSDivision.getSubDivisionName(divisionID);
    if (subDivisionID == null)
    { child.addSubDivision(division);
    }
    else
    { child.addSubDivision(subDivisionID, division);
    }
  }

  /**
   *  Get a subdivision of a given identifier...
   * 
   *  @param <code>String</code> the identifier of the division
   *  @return <code>METSDivision</code> the division, which will be
   *          <code>null</code> if it is not found.
   */
  public METSDivision getDivision(String divisionID)
  { String topDivision = METSDivision.getTopDivisionName(divisionID);

    METSDivision child = (METSDivision) this.children.get(topDivision);
    if (child == null)
    { return null;
    }

    String subDivision = METSDivision.getSubDivisionName(divisionID);
    if (subDivision != null)
    { child = child.getDivision(subDivision);
    }

    return child;
  }

  public void write(PrintWriter writer)
  { Iterator groups = this.children.values().iterator();

    String tag = XMLTools.getOpenTag("mets", "structMap");
    tag = XMLTools.addAttribute(tag, "ID", this.ID.toString());
    tag = XMLTools.addAttribute(tag, "TYPE", this.type);
    tag = XMLTools.addAttribute(tag, "LABEL", this.label);
        
    writer.println(tag);
    while (groups.hasNext())
    { METSDivision group = (METSDivision) groups.next();

      group.write(writer);
    }
    writer.println("</mets:structMap>");
  }


  /**
   *  Write this METSStructure to an SQL database....
   *
   *  @param <code>DocumentInterface</code> the enclosing document.
   *  @param <code>GS3SQLConnection</code> the SQL database connection.
   */
  public boolean writeSQL(DocumentInterface document, GS3SQLConnection connection)
  { int sqlRef = -1;
    ResultSet results;

    // Prepare query to see if this structure has already been written
    GS3SQLSelect select = new GS3SQLSelect("structure");
    select.addField("StructureRef");
    GS3SQLWhereItem whereItem = new GS3SQLWhereItem("DocID", "=", document.getID().toString());
    GS3SQLWhereItem item = new GS3SQLWhereItem("StructureID", "=", this.ID.toString());
    GS3SQLWhere where = new GS3SQLWhere(whereItem);
    where.add(item);
    select.setWhere(where);

    // attempt to execute the query & get the current structure's reference
    try {
      connection.execute(select.toString());
      results = connection.getResultSet();
      if (results != null &&
      results.first())
      { sqlRef = results.getInt("structureRef");
      }
      else 
      { results = null;
      }
    }
    catch (SQLException sqlEx) {
      System.err.print(sqlEx);
      return false;
    }

    // insert a new structure if it wasn't there previously
    if (results == null) {
      GS3SQLInsert insert = new GS3SQLInsert("structure");
      insert.addValue("DocID", document.getID().toString());
      insert.addValue("StructureID", this.ID.toString());
      insert.addValue("StructureType", this.type);
      insert.addValue("Label", this.label);
      
      if (!connection.execute(insert.toString())) {
    return false;
      }

      // get the new structure reference by re-running the original select object
      connection.execute(select.toString());

      try {
    results = connection.getResultSet();
    results.first();
    sqlRef = results.getInt("StructureRef");
      }
      catch (SQLException sql) {
    System.err.println(sql);
    return false;
      }
    }
    else {
      GS3SQLUpdate update = new GS3SQLUpdate("structure");
      update.setWhere(where);

      update.addValue("StructureType", this.type);
      update.addValue("Label", this.label);

      connection.execute(update.toString());
    }
      
    // write out the child groups (Divisions) now...    
    Iterator groups = this.children.values().iterator();

    while (groups.hasNext())
    { METSDivision group = (METSDivision) groups.next();

      if (!group.writeSQL(document.getID(), sqlRef, true, connection))
      { return false;
      }
    }
    return true;
  }


  public static METSStructure readSQL(DocumentInterface document, GS3SQLConnection connection,
                      ResultSet resultSet)
  {
    try {
      String ID    = resultSet.getString("StructureID");
      String type  = resultSet.getString("StructureType");
      String label = resultSet.getString("Label");

      // create the metadata block object
      METSStructure structure = new METSStructure(ID, label, type);
      
      // get its metadata reference to retrieve divisions
      int structureRef = resultSet.getInt("StructureRef");

      // query the database for matching division for this structure block
      GS3SQLSelect select = new GS3SQLSelect("divisions");
      select.addField("*");
      GS3SQLWhereItem whereItem = new GS3SQLWhereItem("ParentRef", "=", Integer.toString(structureRef),
                              GS3SQLField.INTEGER_TYPE);
      GS3SQLWhere where = new GS3SQLWhere(whereItem);
      whereItem = new GS3SQLWhereItem("ParentType", "=", METSDivision.STRUCTURE_PARENT);
      where.add(whereItem);
      select.setWhere(where);

      connection.execute(select.toString());

      // parse through the divisions
      ResultSet divisionSet = connection.getResultSet();
      divisionSet.first();
      do {
    METSDivision division = METSDivision.readSQL(connection, divisionSet);
    if (division != null) {
      structure.addDivision(division);
    }
      }
      while (divisionSet.next());

      return structure;
    }
    catch (SQLException sqlEx)
    { System.out.println(sqlEx);
      System.exit(1);
    }
    return null;
  }
}