/* 
 * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
 *
 * This program 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; version 2 of the
 * License.
 * 
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301  USA
 */

#ifndef _DB_OBJECT_HELPERS_H_
#define _DB_OBJECT_HELPERS_H_

#include <grtpp.h>
#include <grts/structs.db.h>
#include <grts/structs.db.mgmt.h>
#include <grts/structs.db.mysql.h>
#include <set>

#include "wbpublic_public_interface.h"

#include "charset_utils.h"
#include "catalog_templates.h"

// misc helper functions for db objects


// replaces old DbUtils.lua
// the functions here are also exposed as a GRT module in 
// modules/db/dbutils.cpp

db_mgmt_RdbmsRef WBPUBLICBACKEND_PUBLIC_FUNC get_rdbms_for_db_object(const ::grt::ValueRef &object);


namespace bec {

  // these constants for comparing db_SimpleDatatypeRef members. Cannot use -1 because for characterOctetLength it means pow(10, -1)
  const int EMPTY_TYPE_MAXIMUM_LENGTH = 0;
  const int EMPTY_TYPE_OCTET_LENGTH = EMPTY_TYPE_MAXIMUM_LENGTH;
  const int EMPTY_TYPE_PRECISION = EMPTY_TYPE_MAXIMUM_LENGTH;
  const int EMPTY_TYPE_SCALE = EMPTY_TYPE_MAXIMUM_LENGTH;
  // these constants for comparing db_SimpleDatatypeRef members. Cannot use 0 because char(0) and char are different types
  const int EMPTY_COLUMN_LENGTH=    -1;
  const int EMPTY_COLUMN_PRECISION= EMPTY_COLUMN_LENGTH;
  const int EMPTY_COLUMN_SCALE=     EMPTY_COLUMN_LENGTH;
  
  struct WBPUBLICBACKEND_PUBLIC_FUNC CatalogHelper 
  {
    static void apply_defaults(db_mysql_CatalogRef catalog, std::string default_engine);
    static db_SimpleDatatypeRef get_datatype(grt::ListRef<db_SimpleDatatype> types, const std::string &name);
    static GrtVersionRef parse_version(grt::GRT *grt, const std::string &version);
    static bool version_equal(GrtVersionRef a, GrtVersionRef b);
    static bool version_greater(GrtVersionRef a, GrtVersionRef b);
    static bool is_type_valid_for_version(const db_SimpleDatatypeRef &type, const GrtVersionRef &target_version);

    static std::string dbobject_list_to_dragdata(const std::list<db_DatabaseObjectRef> &object);
    static std::list<db_DatabaseObjectRef> dragdata_to_dbobject_list(const db_CatalogRef &catalog, const std::string &object);

    static std::string dbobject_to_dragdata(const db_DatabaseObjectRef &object);
    static db_DatabaseObjectRef dragdata_to_dbobject(const db_CatalogRef &catalog, const std::string &object);
  private:
    static void apply_defaults(db_mysql_ColumnRef column);

  };

  struct WBPUBLICBACKEND_PUBLIC_FUNC SchemaHelper 
  {
    static std::string get_unique_foreign_key_name(const db_SchemaRef &schema, const std::string &prefix,
                                                   int maxlength);

    static std::set<std::string> get_foreign_key_names(const db_SchemaRef &schema);
    static std::string get_unique_foreign_key_name(std::set<std::string> &used_names, 
                                                   const std::string &prefix,
                                                   int maxlength);
  };

  struct WBPUBLICBACKEND_PUBLIC_FUNC TableHelper 
  {
    static db_ForeignKeyRef create_foreign_key_to_table(const db_TableRef &table, 
                                                     const db_TableRef &ref_table,
                                                     bool mandatory, bool ref_mandatory,
                                                     bool many, bool identifying,
                                                        const db_mgmt_RdbmsRef &rdbms,
                                                     const grt::DictRef &global_options,
                                                     const grt::DictRef &options);

    static db_ForeignKeyRef create_foreign_key_to_table(const db_TableRef &table, const std::vector<db_ColumnRef> &columns,
                                                     const db_TableRef &ref_table, const std::vector<db_ColumnRef> &refcolumns,
                                                     bool mandatory,
                                                     bool many, 
                                                        const db_mgmt_RdbmsRef &rdbms,
                                                     const grt::DictRef &global_options,
                                                     const grt::DictRef &options);

    static db_IndexRef create_index_for_fk(grt::GRT *grt, const db_ForeignKeyRef &fk, const size_t max_len = 64);
    static db_IndexRef find_index_usable_by_fk(const db_ForeignKeyRef &fk, const db_IndexRef &other_than = db_IndexRef());
    static std::string generate_foreign_key_name();
    static db_ForeignKeyRef create_empty_foreign_key(grt::GRT *grt, const db_TableRef &table, const std::string &name);
    static void update_foreign_key_index(const db_ForeignKeyRef &fk);

    static bool rename_foreign_key(const db_TableRef &table, db_ForeignKeyRef &fk, const std::string &new_name);
    
    static void update_foreign_keys_from_column_notnull(const db_TableRef &table, const db_ColumnRef &column);
    
    static bool create_missing_indexes_for_foreign_keys(const db_TableRef &table);

    static bool is_identifying_foreign_key(const db_TableRef &table, const db_ForeignKeyRef &fk);

    static db_TableRef create_associative_table(const db_SchemaRef &schema, const db_TableRef &table1, const db_TableRef &table2, 
      bool mandatory1, bool mandatory2, 
                                                const db_mgmt_RdbmsRef &rdbms,
      const grt::DictRef &global_options, const grt::DictRef &options);

    static db_TableRef clone_table(const db_TableRef &table);
    static db_mysql_StorageEngineRef get_engine_by_name(grt::GRT *grt, const std::string &name);
    static std::string get_sync_comment(const std::string &comment, const int max_len = 60);
    static std::string get_document_comment(const std::string &comment, const int max_len = 60);
  };

  enum ColumnTypeCompareResult { COLUMNS_TYPES_EQUAL          = 0, 
         COLUMNS_TYPES_DIFFER         = 1, 
         COLUMNS_CHARSETS_DIFFER      = 2, 
         COLUMNS_COLLATIONS_DIFFER    = 3,
         COLUMNS_FLAGS_DIFFER         = 4,
	 COLUMNS_TYPES_EQUAL_LENGTH_DIFFER = 5
  };

  struct WBPUBLICBACKEND_PUBLIC_FUNC ColumnHelper 
  {
    //static std::string quote_default_if_needed(const db_ColumnRef &column, const std::string &value);

    static void copy_column(const db_ColumnRef &from, db_ColumnRef &to);
    static ColumnTypeCompareResult compare_column_types(const db_ColumnRef &from, const db_ColumnRef &to);

    static void set_default_value(db_ColumnRef column, const std::string &value);
  };

  struct Column_action
  {
    db_mysql_CatalogRef catalog;
    db_mgmt_RdbmsRef rdbms;

    Column_action(db_mysql_CatalogRef c, db_mgmt_RdbmsRef r) 
      : catalog(c), rdbms(r)
    {}

    void operator() (db_mysql_ColumnRef column) 
    {
      db_UserDatatypeRef udt= column->userType();
      if(udt.is_valid())
        column->setParseType(column->formattedType(), catalog->simpleDatatypes());
    }
  };

  struct Table_action
  {
    db_mysql_CatalogRef catalog;
    db_mgmt_RdbmsRef rdbms;

    Table_action(db_mysql_CatalogRef c, db_mgmt_RdbmsRef r) 
      : catalog(c), rdbms(r)
    {}

    void operator() (const db_mysql_TableRef &table) 
    {
      Column_action ca(catalog, rdbms);
      ct::for_each<ct::Columns>(table, ca);
    }
  };


  struct Schema_action
  {
    db_mysql_CatalogRef catalog;
    db_mgmt_RdbmsRef rdbms;

    Schema_action(db_mysql_CatalogRef c, db_mgmt_RdbmsRef r) 
      : catalog(c), rdbms(r)
    {}

    void operator() (const db_mysql_SchemaRef &schema) 
    {
      Table_action table_action(catalog, rdbms);
      ct::for_each<ct::Tables>(schema, table_action);
    }
  };

  inline void apply_user_datatypes(db_mysql_CatalogRef cat, db_mgmt_RdbmsRef rdbms)
  {
    Schema_action sa(cat, rdbms);
    ct::for_each<ct::Schemata>(cat, sa);
  }
  bool parseType(const std::string &type,
    const GrtVersionRef &target_version,
    const grt::ListRef<db_SimpleDatatype> &typeList,
    const grt::ListRef<db_UserDatatype>& user_types,
    const grt::ListRef<db_SimpleDatatype>& default_type_list,
    db_SimpleDatatypeRef &simpleType,
    db_UserDatatypeRef& userType,
    int &precision,
    int &scale,
    int &length,
    std::string &datatypeExplicitParams);

};

#endif /* _DB_OBJECT_HELPERS_H_ */
