/*
 * This file is part of Zql.
 *
 * Zql is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Zql is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Zql.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.gibello.zql;

import java.io.* ;
import java.util.* ;

/**
 * A name/alias association<br>
 * Names can have two forms:
 * <ul>
 * <li>FORM_TABLE for table names ([schema.]table)</li>
 * <li>FORM_COLUMN for column names ([[schema.]table.]column)</li>
 * </ul>
 */
public class ZAliasedName implements java.io.Serializable {

  String strform_ = "";
  String schema_ = null;
  String table_ = null;
  String column_ = null;
  String alias_ = null;

  public static int FORM_TABLE = 1;
  public static int FORM_COLUMN = 2;

  int form_ = FORM_COLUMN;

  public ZAliasedName() {}

  /**
   * Create a new ZAliasedName given it's full name.
   * @param fullname The full name: [[schema.]table.]column
   * @param form The name form (FORM_TABLE or FORM_COLUMN)
   */
  public ZAliasedName(String fullname, int form) {

    form_ = form;
    strform_ = new String(fullname);

    StringTokenizer st = new StringTokenizer(fullname, ".");
    switch(st.countTokens()) {
      case 1:
        if(form == FORM_TABLE) table_ = new String(st.nextToken());
        else column_ = new String(st.nextToken());
        break;
      case 2:
        if(form == FORM_TABLE) {
          schema_ = new String(st.nextToken());
          table_ = new String(st.nextToken());
        } else {
          table_ = new String(st.nextToken());
          column_ = new String(st.nextToken());
        }
        break;
      case 3:
      default:
        schema_ = new String(st.nextToken());
        table_ = new String(st.nextToken());
        column_ = new String(st.nextToken());
        break;
    }
    schema_ = postProcess(schema_);
    table_ = postProcess(table_);
    column_ = postProcess(column_);
  }

  private String postProcess(String val) {
    if(val == null) return null;
    if(val.indexOf("(") >= 0) val = val.substring(val.lastIndexOf("(") + 1);
    if(val.indexOf(")") >= 0) val = val.substring(0, val.indexOf(")"));
    return val.trim();
  }

  public String toString() {
    if(alias_ == null) return strform_;
    else return strform_ + " " + alias_;
  }

  /**
   * @return If the name is of the form schema.table.column,
   * returns the schema part
   */
  public String getSchema() { return schema_; }

  /**
   * @return If the name is of the form [schema.]table.column,
   * returns the schema part
   */
  public String getTable() { return table_; }

  /**
   * @return The name is of the form [[schema.]table.]column:
   * return the column part
   */
  public String getColumn() { return column_; }

  /**
   * @return true if column is "*", false otherwise.
   * Example: *, table.* are wildcards.
   */
  public boolean isWildcard() {
    if(form_ == FORM_TABLE) return table_ != null && table_.equals("*");
    else return column_ != null && column_.indexOf('*') >= 0;
  }

  /**
   * @return the alias associated to the current name.
   */
  public String getAlias() { return alias_; }

  /**
   * Associate an alias with the current name.
   * @param a the alias associated to the current name.
   */
  public void setAlias(String a) { alias_ = new String(a); }
}