package liquibase.change.core;

 import java.util.ArrayList;

 import java.util.List;

 import liquibase.change.AbstractChange;

 import liquibase.change.Change;

 import liquibase.change.ChangeMetaData;

 import liquibase.change.ColumnConfig;

 import liquibase.database.Database;

 import liquibase.database.core.DB2Database;

 import liquibase.database.core.SQLiteDatabase;

 import liquibase.database.core.SQLiteDatabase.AlterTableVisitor;

 import liquibase.database.structure.Index;

 import liquibase.statement.SqlStatement;

 import liquibase.statement.core.AddPrimaryKeyStatement;

 import liquibase.statement.core.ReorganizeTableStatement;

 import liquibase.util.StringUtils;

 /**

  * Creates a primary key out of an existing column or set of columns.

  */

 public class AddPrimaryKeyChange extends AbstractChange {

     private String schemaName;

     private String tableName;

     private String tablespace;

     private String columnNames;

     private String constraintName;

     public AddPrimaryKeyChange() {

         super("addPrimaryKey", "Add Primary Key", ChangeMetaData.PRIORITY_DEFAULT);

     }

     public String getTableName() {

         return tableName;

     }

     public void setTableName(String tableName) {

         this.tableName = tableName;

     }

     public String getSchemaName() {

         return schemaName;

     }

     public void setSchemaName(String schemaName) {

         this.schemaName = StringUtils.trimToNull(schemaName);

     }

     public String getColumnNames() {

         return columnNames;

     }

     public void setColumnNames(String columnNames) {

         this.columnNames = columnNames;

     }

     public String getConstraintName() {

         return constraintName;

     }

     public void setConstraintName(String constraintName) {

         this.constraintName = constraintName;

     }

     public String getTablespace() {

         return tablespace;

     }

     public void setTablespace(String tablespace) {

         this.tablespace = tablespace;

     }

     @Override

     public SqlStatement[] generateStatements(Database database) {

         String schemaName = getSchemaName() == null ? database.getDefaultSchemaName() : getSchemaName();

         AddPrimaryKeyStatement statement = new AddPrimaryKeyStatement(schemaName, getTableName(), getColumnNames(),

                 getConstraintName());

         statement.setTablespace(getTablespace());

         if (database instanceof DB2Database) {

             return new SqlStatement[] { statement, new ReorganizeTableStatement(schemaName, getTableName()) };

             // todo } else if (database instanceof SQLiteDatabase) {

             // // return special statements for SQLite databases

             // return generateStatementsForSQLiteDatabase(database);

         }

         return new SqlStatement[] { statement };

     }

     private SqlStatement[] generateStatementsForSQLiteDatabase(Database database) {

         // SQLite does not support this ALTER TABLE operation until now.

         // or more information: http://www.sqlite.org/omitted.html

         // This is a small work around...

         List<SqlStatement> statements = new ArrayList<SqlStatement>();

         // define alter table logic

         AlterTableVisitor rename_alter_visitor = new AlterTableVisitor() {

             @Override

             public ColumnConfig[] getColumnsToAdd() {

                 return new ColumnConfig[0];

             }

             @Override

             public boolean copyThisColumn(ColumnConfig column) {

                 return true;

             }

             @Override

             public boolean createThisColumn(ColumnConfig column) {

                 String[] split_columns = getColumnNames().split("[ ]*,[ ]*");

                 for (String split_column : split_columns) {

                     if (column.getName().equals(split_column)) {

                         column.getConstraints().setPrimaryKey(true);

                     }

                 }

                 return true;

             }

             @Override

             public boolean createThisIndex(Index index) {

                 return true;

             }

         };

         try {

             // alter table

             statements.addAll(SQLiteDatabase.getAlterTableStatements(rename_alter_visitor, database, getSchemaName(),

                     getTableName()));

         } catch (Exception e) {

             e.printStackTrace();

         }

         return statements.toArray(new SqlStatement[statements.size()]);

     }

     @Override

     protected Change[] createInverses() {

         DropPrimaryKeyChange inverse = new DropPrimaryKeyChange();

         inverse.setSchemaName(getSchemaName());

         inverse.setTableName(getTableName());

         inverse.setConstraintName(getConstraintName());

         return new Change[] { inverse, };

     }

     @Override

     public String getConfirmationMessage() {

         return "Primary key added to " + getTableName() + " (" + getColumnNames() + ")";

     }

 }