Database Helper Class Library to Ease Database Operation

///////////////////////////////////////////////////////////////////////////
// Copyright 2003-2005 Falcon Soon
//
// Author: Soon Chun Boon
// Date: 24 October 2004
// Description: 
// Class that groups a number of DBRelation instance related to 
// SqlTableHelper instance.
///////////////////////////////////////////////////////////////////////////
using System;
using System.Data;
using System.Collections;


namespace DBHelper.SqlClient
{
	/// <summary>
    /// Class that groups a number of <see cref="DBHelper.DBRelation"/> instance related to 
    /// <see cref="DBHelper.SqlClient.SqlTableHelper"/> instance.
	/// </summary>
	internal class SqlTableRelationCollection : DBRelationCollection
	{
        #region Class Member Declarations
        private ArrayList malCollection;
        private SqlTableHelper mobjTable;
        private bool mbParentCollection;
        #endregion

        /// <summary>
        /// Initializes a new instance of <see cref="DBHelper.SqlClient.SqlTableRelationCollection"/>
        /// with the specified <see cref="DBHelper.SqlClient.SqlTableHelper"/> instance and a value
        /// specifying whether this collection is parent or child collection.
        /// </summary>
        /// <param name="objTable">The <see cref="DBHelper.SqlClient.SqlTableHelper"/> instance.</param>
        /// <param name="bParentCollection">True if parent collection otherwise False
        /// if child collection.</param>
        /// <exception cref="DBHelper.DataException.RelationTableNull">
        /// <i>objTable</i> parameter is not provided.
        /// </exception>
        internal SqlTableRelationCollection(SqlTableHelper objTable, bool bParentCollection)
        {
            if (objTable == null)
            {
                throw new DataException.RelationTableNull();
            }
            this.mobjTable = objTable;
            this.mbParentCollection = bParentCollection;
            this.malCollection = new ArrayList();
        }

        /// <summary>
        /// Adds a <see cref="DBHelper.DBRelation"/> instance to collection.
        /// </summary>
        /// <param name="objRelation">The relation to add.</param>
        private void AddCache(DBRelation objRelation)
        {
            this.malCollection.Add(objRelation);
        }

        /// <summary>
        /// Adds a <see cref="DBHelper.DBRelation"/> instance to collection.
        /// </summary>
        /// <param name="objRelation">The relation to add.</param>
        /// <exception cref="DBHelper.DataException.ChildTableMismatch">
        /// Child table in relation is mismatch with this collection's TableHelper
        /// instance (for parent collection).
        /// </exception>
        /// <exception cref="DBHelper.DataException.ParentTableMismatch">
        /// Parent table in relation is mismatch with this collection's TableHelper
        /// instance (for child collection).
        /// </exception>
        /// <exception cref="DBHelper.DataException.DuplicateNameException">
        /// Relation with the same name already exist in collection.
        /// </exception>
        protected override void AddCore(DBRelation objRelation)
        {
            if (this.mbParentCollection)
            {
                if (objRelation.ChildTable != this.mobjTable.Data)
                {
                    throw new DataException.ChildTableMismatch();
                }
            }
            else if (objRelation.ParentTable != this.mobjTable.Data)
            {
                throw new DataException.ParentTableMismatch();
            }

            if (this[objRelation.RelationName] != null)
            {
                throw new DataException.DuplicateNameException(objRelation.RelationName + 
                                              " is duplicate in collection.");
            }

            this.AddCache(objRelation);
        }

        /// <summary>
        /// Remove a <see cref="DBHelper.DBRelation"/> instance from collection.
        /// </summary>
        /// <param name="objRelation">The relation to remove.</param>
        /// <exception cref="DBHelper.DataException.RelationDoesNotExist">
        /// The relation to remove is not exist.
        /// </exception>
        private void RemoveCache(DBRelation objRelation)
        {
            for (int iIndex = 0; iIndex < this.malCollection.Count; iIndex++)
            {
                if (objRelation == this.malCollection[iIndex])
                {
                    this.malCollection.RemoveAt(iIndex);                    
                    return;
                }
            }
            throw new DataException.RelationDoesNotExist();
        }

        /// <summary>
        /// Remove a <see cref="DBHelper.DBRelation"/> instance from collection.
        /// </summary>
        /// <param name="objRelation">The relation to remove.</param>
        /// <exception cref="DBHelper.DataException.RelationDoesNotExist">
        /// The relation to remove is not exist.
        /// </exception>
        /// <exception cref="DBHelper.DataException.ChildTableMismatch">
        /// Child table in relation is mismatch with this collection's TableHelper
        /// instance (for parent collection).
        /// </exception>
        /// <exception cref="DBHelper.DataException.ParentTableMismatch">
        /// Parent table in relation is mismatch with this collection's TableHelper
        /// instance (for child collection).
        /// </exception>
        protected override void RemoveCore(DBRelation objRelation)
        {
            if (this.mbParentCollection)
            {
                if (objRelation.ChildTable != this.mobjTable.Data)
                {
                    throw new DataException.ChildTableMismatch();
                }
            }
            else if (objRelation.ParentTable != this.mobjTable.Data)
            {
                throw new DataException.ParentTableMismatch();
            }
            this.RemoveCache(objRelation);
        }

        /// <summary>
        /// Gets <see cref="DBHelper.DBRelation"/> instance with the specified index.
        /// </summary>
        /// <exception cref="DBHelper.DataException.RelationOutOfRange">
        /// The specified index is out of range of collection.
        /// </exception>
        public override DBRelation this[int iIndex]
        {
            get
            {
                if ((iIndex < 0) || (iIndex >= this.malCollection.Count))
                {
                    throw new DataException.RelationOutOfRange(iIndex);
                }
                return (DBRelation) this.List[iIndex];
            }
        }

        /// <summary>
        /// Gets the <see cref="DBHelper.DBRelation"/> instance with 
        /// the specified relation name.
        /// </summary>
        /// <remarks>
        /// Comparison is case insensitive. If no relation name is matched, Null is returned.
        /// </remarks>
        /// <exception cref="DBHelper.DataException.CaseInsensitiveNameConflict">
        /// 2 or more relations with same name (case insensitive) are found.
        /// </exception>
        public override DBRelation this[string strName]
        {
            get
            {
                int iIndex = base.InternalIndexOf(strName);
                if (iIndex == -2)
                {
                    throw new DataException.CaseInsensitiveNameConflict(strName);
                }
                if (iIndex >= 0)
                {
                    return (DBRelation) this.List[iIndex];
                }
                return null;
            }
        }

        #region Class Property Declaration

        /// <summary>
        /// Gets the collection instance that is used to group
        /// <see cref="DBHelper.DBRelation"/> instances.
        /// </summary>
        /// <exception cref="System.ArgumentNullException">
        /// <see cref="DBHelper.SqlClient.SqlTableHelper"/> instance is not provided.
        /// </exception>
        protected override ArrayList List
        {
            get
            {
                if (this.mobjTable == null)
                {
                    throw new ArgumentNullException("objTable");
                }
                return (this.malCollection);
            }
        }
        #endregion
	}
}