#region MIT license
// 
// MIT license
//
// Copyright (c) 2007-2008 Jiri Moudry, Pascal Craponne
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
// 
#endregion
using System.Collections.Generic;
using System.Data;
using DbLinq.Util;
using DbLinq.Vendor;

namespace DbLinq.Ingres
{
    partial class IngresSchemaLoader
    {
        protected virtual string GetFullType(IDataTableColumn column)
        {
            switch (column.SqlType.ToLower())
            {
            case "c":
            case "char":
            case "nchar":
            case "varchar":
            case "nvarchar":
            case "long varchar":
            case "text":
            case "integer":
                return column.SqlType + "(" + column.Length + ")";

            case "decimal":
                return column.SqlType + "(" + column.Length + ", " + column.Scale + ")";

            default:
                return column.SqlType;
            }
        }

        protected virtual IDataTableColumn ReadColumn(IDataRecord rdr)
        {
            var column = new DataTableColumn();
            int field = 0;
            column.TableSchema = rdr.GetAsString(field++).Trim();
            column.TableName = rdr.GetAsString(field++).Trim();
            column.ColumnName = rdr.GetAsString(field++).Trim();
            string nullableStr = rdr.GetAsString(field++);
            column.Nullable = nullableStr == "Y";
            column.SqlType = rdr.GetAsString(field++).Trim();
            column.DefaultValue = rdr.GetAsString(field++);
            column.Generated = column.DefaultValue != null && column.DefaultValue.StartsWith("next value for");

            column.Length = rdr.GetAsNullableNumeric<long>(field++);
            column.Scale = rdr.GetAsNullableNumeric<int>(field++);
            column.FullType = GetFullType(column);
            return column;
        }

        protected override IList<IDataTableColumn> ReadColumns(IDbConnection connectionString, string databaseName)
        {
            const string sql = @"SELECT t.table_owner, t.table_name, column_name, " + 
                "column_nulls, column_datatype, column_default_val, " + 
                "column_length, column_scale " + 
                "FROM iicolumns c join iitables t on " + 
                "(c.table_name=t.table_name and c.table_owner=t.table_owner) " + 
                "WHERE t.table_owner <> '$ingres' and t.table_type in ('T', 'V') " + 
                "AND t.table_name NOT LIKE 'ii%' " + 
                "ORDER BY column_sequence";

            return DataCommand.Find<IDataTableColumn>(connectionString, sql, ReadColumn);
        }
    }
}
