using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;

namespace Ant.ORM
{
    /// <summary>
    /// 参数集合
    /// </summary>
    public class QueryParameterCollection : MarshalByRefObject, IEnumerable, IEnumerator
    {
        private int position;
        private List<QueryParameter> item;
        public QueryParameterCollection()
        {
            item = new List<QueryParameter>();
            position = -1;
        }
        public QueryParameterCollection(int capacity)
        {
            item = new List<QueryParameter>(capacity);
            position = -1;
        }
        public QueryParameter Add(QueryParameter parameter)
        {
            item.Add(parameter);
            return item[item.Count - 1];
        }
        public QueryParameter Add(string parameterName, object Value)
        {
            QueryParameter parameter = new QueryParameter(parameterName, Value);
            item.Add(parameter);
            return item[item.Count - 1];
        }
        public QueryParameter Add(string parameterName, DbType dbType)
        {
            QueryParameter parameter = new QueryParameter(parameterName, dbType);
            item.Add(parameter);
            return parameter;
        }
        public QueryParameter Add(string parameterName, DbType dbType, object value)
        {
            QueryParameter parameter = new QueryParameter();
            parameter.ParameterName = parameterName;
            parameter.DbType = dbType;
            parameter.Value = value;
            item.Add(parameter);
            return item[item.Count - 1];
        }
        public QueryParameter Add(string parameterName, DbType dbType, int size, string sourceColumn)
        {
            QueryParameter parameter = new QueryParameter(parameterName, dbType, size, sourceColumn);
            item.Add(parameter);
            return item[item.Count - 1];
        }
        public QueryParameter Add(string parameterName, DbType dbType, int size, ParameterDirection direction, bool isNullable, byte precision, byte scale, string sourceColumn, DataRowVersion sourceVersion, object Value)
        {
            QueryParameter parameter = new QueryParameter(parameterName, dbType, size, direction, isNullable, precision, scale, sourceColumn, sourceVersion, Value);
            item.Add(parameter);
            return item[item.Count - 1];
        }

        public int Count
        {
            get
            {
                return item.Count;
            }
        }
        public QueryParameter this[int index]
        {
            get
            {
                return (QueryParameter)item[index];
            }
            set
            {
                item[index] = value;
            }
        }

        public QueryParameter this[string parameterName]
        {
            get
            {
                return (QueryParameter)item[this.IndexOf(parameterName)];
            }
            set
            {
                item[this.IndexOf(parameterName)] = value;
            }
        }

        /// <summary>
        /// 返回参数在集合中的位置
        /// </summary>
        /// <param name="parameterName"></param>
        /// <returns></returns>
        public int IndexOf(string parameterName)
        {
            int index = -1;
            for (int i = 0; i < item.Count; i++)
            {
                if (item[i].ParameterName.Equals(parameterName))
                {
                    index = i;
                    break;
                }
            }
            return index;
        }
        /// <summary>
        /// 清除所有参数
        /// </summary>
        public void Clear()
        {
            item.Clear();
            position = -1;
        }



        #region IEnumerable 成员

        IEnumerator IEnumerable.GetEnumerator()
        {
            return this;
        }

        #endregion

        #region IEnumerator 成员

        public object Current
        {
            get { return this.item[position]; }
        }

        public bool MoveNext()
        {
            if (position < this.item.Count - 1)
            {
                position++;
                return true;
            }
            else
            {
                return false;
            }

        }

        public void Reset()
        {
            position = -1;
        }

        #endregion
    }
}