content: /*
   * Copyright 1999-2017 Alibaba Group Holding Ltd.
   *
   * 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 com.alibaba.druid.sql.ast.statement;
  
  import com.alibaba.druid.sql.SQLUtils;
  import com.alibaba.druid.sql.ast.SQLExpr;
  import com.alibaba.druid.sql.ast.SQLIndexDefinition;
  import com.alibaba.druid.sql.ast.SQLName;
  import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
  import com.alibaba.druid.sql.ast.expr.SQLIntegerExpr;
  import com.alibaba.druid.sql.ast.expr.SQLMethodInvokeExpr;
  import com.alibaba.druid.sql.visitor.SQLASTVisitor;
  
  import java.util.List;
  
  public class SQLUnique extends SQLConstraintImpl implements SQLUniqueConstraint, SQLTableElement {
      protected final SQLIndexDefinition indexDefinition = new SQLIndexDefinition();
  
      protected boolean disableNovalidate;
      public SQLUnique() {
          indexDefinition.setParent(this);
      }
  
      // Override name and comment in constraint impl.
      @Override
      public SQLName getName() {
          return indexDefinition.getName();
      }
  
      @Override
      public void setName(SQLName name) {
          indexDefinition.setName(name);
      }
  
      @Override
      public void setName(String name) {
          this.setName(new SQLIdentifierExpr(name));
      }
  
      public boolean isDisableNovalidate() {
          return disableNovalidate;
      }
  
      public void setDisableNovalidate(boolean disableNovalidate) {
          this.disableNovalidate = disableNovalidate;
      }
  
      @Override
      public SQLExpr getComment() {
          if (indexDefinition.hasOptions()) {
              return indexDefinition.getOptions().getComment();
          }
          return null;
      }
  
      @Override
      public void setComment(SQLExpr x) {
          indexDefinition.getOptions().setComment(x);
      }
  
      public SQLIndexDefinition getIndexDefinition() {
          return indexDefinition;
      }
  
      public List<SQLSelectOrderByItem> getColumns() {
          return indexDefinition.getColumns();
      }
  
      public void addColumn(SQLExpr column) {
          if (column == null) {
              return;
          }
  
          addColumn(new SQLSelectOrderByItem(column));
      }
  
      public void addColumn(SQLSelectOrderByItem column) {
          if (column != null) {
              column.setParent(this);
          }
          indexDefinition.getColumns().add(column);
      }
  
      @Override
      protected void accept0(SQLASTVisitor visitor) {
          if (visitor.visit(this)) {
              acceptChild(visitor, getName());
              acceptChild(visitor, getColumns());
              acceptChild(visitor, getCovering());
          }
          visitor.endVisit(this);
      }
  
      public boolean containsColumn(String column) {
          for (SQLSelectOrderByItem item : getColumns()) {
              SQLExpr expr = item.getExpr();
              if (expr instanceof SQLIdentifierExpr) {
                  if (SQLUtils.nameEquals(((SQLIdentifierExpr) expr).getName(), column)) {
                      return true;
                  }
              }
          }
          return false;
      }
  
      public boolean containsColumn(long columnNameHash) {
          for (SQLSelectOrderByItem item : getColumns()) {
              SQLExpr expr = item.getExpr();
              if (expr instanceof SQLIdentifierExpr) {
                  if (((SQLIdentifierExpr) expr).nameHashCode64() == columnNameHash) {
                      return true;
                  }
              }
          }
          return false;
      }
  
      public void cloneTo(SQLUnique x) {
          super.cloneTo(x);
  
          indexDefinition.cloneTo(x.indexDefinition);
      }
  
      public SQLUnique clone() {
          SQLUnique x = new SQLUnique();
          cloneTo(x);
          return x;
      }
  
      public void simplify() {
          super.simplify();
  
          for (SQLSelectOrderByItem item : getColumns()) {
              SQLExpr column = item.getExpr();
              if (column instanceof SQLIdentifierExpr) {
                  SQLIdentifierExpr identExpr = (SQLIdentifierExpr) column;
                  String columnName = identExpr.getName();
                  String normalized = SQLUtils.normalize(columnName, dbType);
                  if (normalized != columnName) {
                      item.setExpr(new SQLIdentifierExpr(columnName));
                  }
              }
          }
      }
  
      public boolean applyColumnRename(SQLName columnName, SQLColumnDefinition to) {
          for (SQLSelectOrderByItem orderByItem : getColumns()) {
              SQLExpr expr = orderByItem.getExpr();
              if (expr instanceof SQLName
                      && SQLUtils.nameEquals((SQLName) expr, columnName)) {
                  orderByItem.setExpr(to.getName().clone());
                  return true;
              }
  
              if (expr instanceof SQLMethodInvokeExpr
                      && SQLUtils.nameEquals(((SQLMethodInvokeExpr) expr).getMethodName(), columnName.getSimpleName())) {
                  // More complex when with key length.
                  if (1 == ((SQLMethodInvokeExpr) expr).getArguments().size() &&
                          ((SQLMethodInvokeExpr) expr).getArguments().get(0) instanceof SQLIntegerExpr) {
                      if (to.getDataType().hasKeyLength() &&
                              1 == to.getDataType().getArguments().size() &&
                              to.getDataType().getArguments().get(0) instanceof SQLIntegerExpr) {
                          int newKeyLength = ((SQLIntegerExpr) to.getDataType().getArguments().get(0)).getNumber().intValue();
                          int oldKeyLength = ((SQLIntegerExpr) ((SQLMethodInvokeExpr) expr).getArguments().get(0)).getNumber().intValue();
                          if (newKeyLength > oldKeyLength) {
                              // Change name and keep key length.
                              ((SQLMethodInvokeExpr) expr).setMethodName(to.getName().getSimpleName());
                              return true;
                          }
                      }
                      // Remove key length.
                      orderByItem.setExpr(to.getName().clone());
                      return true;
                  }
              }
          }
          return false;
      }
  
      public boolean applyDropColumn(SQLName columnName) {
          for (int i = getColumns().size() - 1; i >= 0; i--) {
              SQLExpr expr = getColumns().get(i).getExpr();
              if (expr instanceof SQLName
                      && SQLUtils.nameEquals((SQLName) expr, columnName)) {
                  getColumns().remove(i);
                  return true;
              }
  
              if (expr instanceof SQLMethodInvokeExpr
                      && SQLUtils.nameEquals(((SQLMethodInvokeExpr) expr).getMethodName(), columnName.getSimpleName())) {
                  getColumns().remove(i);
                  return true;
              }
          }
          return false;
      }
  
      public List<SQLName> getCovering() {
          return indexDefinition.getCovering();
      }
  }
  