System.Data.SQLite

    {
      return UnsafeNativeMethods.sqlite3_aggregate_context(context, 1);
    }

#if INTEROP_VIRTUAL_TABLE
    /// <summary>
    /// Calls the native SQLite core library in order to declare a virtual table
    /// in response to a call into the <see cref="ISQLiteNativeModule.xCreate" />
    /// or <see cref="ISQLiteNativeModule.xConnect" /> virtual table methods.
    /// </summary>
    /// <param name="module">
    /// The virtual table module that is to be responsible for the virtual table
    /// being declared.
    /// </param>
    /// <param name="strSql">
    /// The string containing the SQL statement describing the virtual table to

            if (pSql != IntPtr.Zero)
            {
                SQLiteMemory.Free(pSql);
                pSql = IntPtr.Zero;
            }
        }
    }

    /// <summary>
    /// Calls the native SQLite core library in order to declare a virtual table
    /// function in response to a call into the <see cref="ISQLiteNativeModule.xCreate" />
    /// or <see cref="ISQLiteNativeModule.xConnect" /> virtual table methods.
    /// </summary>
    /// <param name="module">
    /// The virtual table module that is to be responsible for the virtual table
    /// function being declared.
    /// </param>
    /// <param name="argumentCount">
    /// The number of arguments to the function being declared.
    /// </param>
    /// <param name="name">
    /// The name of the function being declared.
    /// </param>
    /// <param name="error">
    /// Upon success, the contents of this parameter are undefined.  Upon failure,
    /// it should contain an appropriate error message.
    /// </param>
    /// <returns>
    /// A standard SQLite return code.
    /// </returns>
    internal override SQLiteErrorCode DeclareVirtualFunction(
        SQLiteModule module,
        int argumentCount,
        string name,
        ref string error
        )
    {
        if (_sql == null)
        {
            error = "connection has an invalid handle";
            return SQLiteErrorCode.Error;
        }

        IntPtr pName = IntPtr.Zero;

        try
        {
            pName = SQLiteString.Utf8IntPtrFromString(name);

            SQLiteErrorCode n = UnsafeNativeMethods.sqlite3_overload_function(
                _sql, pName, argumentCount);

            if (n != SQLiteErrorCode.Ok) error = GetLastError();

            return n;
        }
        finally
        {
            if (pName != IntPtr.Zero)
            {
                SQLiteMemory.Free(pName);
                pName = IntPtr.Zero;
            }
        }
    }
#endif

    /// <summary>
    /// Enables or disabled extension loading by SQLite.
    /// </summary>
    /// <param name="bOnOff">
    /// True to enable loading of extensions, false to disable.

    /// The module object previously passed to the <see cref="CreateModule" />
    /// method.
    /// </param>
    internal abstract void DisposeModule(SQLiteModule module);

    /// <summary>
    /// Calls the native SQLite core library in order to declare a virtual table
    /// in response to a call into the <see cref="ISQLiteNativeModule.xCreate" />
    /// or <see cref="ISQLiteNativeModule.xConnect" /> virtual table methods.
    /// </summary>
    /// <param name="module">
    /// The virtual table module that is to be responsible for the virtual table
    /// being declared.
    /// </param>
    /// <param name="strSql">
    /// The string containing the SQL statement describing the virtual table to
    /// be declared.
    /// </param>
    /// <param name="error">
    /// Upon success, the contents of this parameter are undefined.  Upon failure,
    /// it should contain an appropriate error message.
    /// </param>
    /// <returns>
    /// A standard SQLite return code.
    /// </returns>
    internal abstract SQLiteErrorCode DeclareVirtualTable(SQLiteModule module, string strSql, ref string error);

    /// <summary>
    /// Calls the native SQLite core library in order to declare a virtual table
    /// function in response to a call into the <see cref="ISQLiteNativeModule.xCreate" />
    /// or <see cref="ISQLiteNativeModule.xConnect" /> virtual table methods.
    /// </summary>
    /// <param name="module">
    /// The virtual table module that is to be responsible for the virtual table
    /// function being declared.
    /// </param>
    /// <param name="argumentCount">
    /// The number of arguments to the function being declared.
    /// </param>
    /// <param name="name">
    /// The name of the function being declared.
    /// </param>
    /// <param name="error">
    /// Upon success, the contents of this parameter are undefined.  Upon failure,
    /// it should contain an appropriate error message.
    /// </param>
    /// <returns>
    /// A standard SQLite return code.
    /// </returns>
    internal abstract SQLiteErrorCode DeclareVirtualFunction(SQLiteModule module, int argumentCount, string name, ref string error);
#endif

    /// <summary>
    /// Enables or disabled extension loading by SQLite.
    /// </summary>
    /// <param name="bOnOff">
    /// True to enable loading of extensions, false to disable.

    /// <summary>
    /// Internal constructor, initializes the function's internal variables.
    /// </summary>
    protected SQLiteFunction()
    {
      _contextDataList = new Dictionary<IntPtr, AggregateData>();
    }

    /// <summary>
    /// Constructs an instance of this class using the specified data-type
    /// conversion parameters.
    /// </summary>
    /// <param name="format">
    /// The DateTime format to be used when converting string values to a
    /// DateTime and binding DateTime parameters.
    /// </param>
    /// <param name="kind">
    /// The <see cref="DateTimeKind" /> to be used when creating DateTime
    /// values.
    /// </param>
    /// <param name="formatString">
    /// The format string to be used when parsing and formatting DateTime
    /// values.
    /// </param>
    /// <param name="utf16">
    /// Non-zero to create a UTF-16 data-type conversion context; otherwise,
    /// a UTF-8 data-type conversion context will be created.
    /// </param>
    protected SQLiteFunction(
        SQLiteDateFormats format,
        DateTimeKind kind,
        string formatString,
        bool utf16
        )
        : this()
    {
        if (utf16)
            _base = new SQLite3_UTF16(format, kind, formatString, IntPtr.Zero, null, false);
        else
            _base = new SQLite3(format, kind, formatString, IntPtr.Zero, null, false);
    }

    ///////////////////////////////////////////////////////////////////////////////////////////////

    #region IDisposable Members
    /// <summary>
    /// Disposes of any active contextData variables that were not automatically cleaned up.  Sometimes this can happen if
    /// someone closes the connection while a DataReader is open.

        /// <summary>
        /// This field is used to store the virtual table cursor instances
        /// associated with this module.  The native pointer to the
        /// sqlite3_vtab_cursor derived structure is used to key into this
        /// collection.
        /// </summary>
        private Dictionary<IntPtr, SQLiteVirtualTableCursor> cursors;

        ///////////////////////////////////////////////////////////////////////

        /// <summary>
        /// This field is used to store the virtual table function instances
        /// associated with this module.  The case-insensitive function name
        /// and the number of arguments (with -1 meaning "any") are used to
        /// construct the string that is used to key into this collection.
        /// </summary>
        private Dictionary<string, SQLiteFunction> functions;
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Public Constructors
        /// <summary>
        /// Constructs an instance of this class.
        /// </summary>
        /// <param name="name">
        /// The name of the module.  This parameter cannot be null.
        /// </param>
        public SQLiteModule(string name)
        {
            if (name == null)
                throw new ArgumentNullException("name");

            this.name = name;
            this.tables = new Dictionary<IntPtr, SQLiteVirtualTable>();
            this.cursors = new Dictionary<IntPtr, SQLiteVirtualTableCursor>();
            this.functions = new Dictionary<string, SQLiteFunction>();
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Internal Methods
        /// <summary>

            return pCursor;
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Function Lookup Methods
        /// <summary>
        /// Deterimines the key that should be used to identify and store the
        /// function instance for the virtual table (i.e. to be returned via
        /// the <see cref="ISQLiteNativeModule.xFindFunction" /> method).
        /// </summary>
        /// <param name="argumentCount">
        /// The number of arguments to the virtual table function.
        /// </param>
        /// <param name="name">
        /// The name of the virtual table function.
        /// </param>
        /// <param name="function">
        /// The <see cref="SQLiteFunction" /> object instance associated with
        /// this virtual table function.
        /// </param>
        /// <returns>
        /// The string that should be used to identify and store the virtual
        /// table function instance.  This method cannot return null.  If null
        /// is returned from this method, the behavior is undefined.
        /// </returns>
        protected virtual string GetFunctionKey(
            int argumentCount,
            string name,
            SQLiteFunction function
            )
        {
            return String.Format("{0}:{1}", argumentCount, name);
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Table Declaration Helper Methods
        /// <summary>
        /// Attempts to declare the schema for the virtual table using the
        /// specified database connection.
        /// </summary>
        /// <param name="connection">
        /// The <see cref="SQLiteConnection" /> object instance to use when

                error = "connection has invalid handle";
                return SQLiteErrorCode.Error;
            }

            return sqliteBase.DeclareVirtualTable(this, sql, ref error);
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Function Declaration Helper Methods
        protected virtual SQLiteErrorCode DeclareFunction(
            SQLiteConnection connection,
            int argumentCount,
            string name,
            ref string error
            )
        {
            if (connection == null)
            {
                error = "invalid connection";
                return SQLiteErrorCode.Error;
            }

            SQLiteBase sqliteBase = connection._sql;

            if (sqliteBase == null)
            {
                error = "connection has invalid handle";
                return SQLiteErrorCode.Error;
            }

            return sqliteBase.DeclareVirtualFunction(
                this, argumentCount, name, ref error);
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Error Handling Helper Methods
        /// <summary>
        /// Arranges for the specified error message to be placed into the
        /// zErrMsg field of a sqlite3_vtab derived structure, freeing the

        {
            try
            {
                SQLiteVirtualTable table = TableFromIntPtr(pVtab);

                if (table != null)
                {
                    string name = SQLiteString.StringFromUtf8IntPtr(zName);
                    SQLiteFunction function = null;

                    if (FindFunction(


                            table, nArg, name, ref function, ref pClientData))
                    {
                        if (function != null)
                        {
                            string key = GetFunctionKey(nArg, name, function);

                            functions[key] = function;
                            callback = function.ScalarCallback;

                            return 1;
                        }
                        else
                        {
                            SetTableError(pVtab, "no function was created");
                        }
                    }

        /// <see cref="Dispose()" /> method.  Zero if this method is being
        /// called from the finalizer.
        /// </param>
        protected virtual void Dispose(bool disposing)
        {
            if (!disposed)
            {
                if (disposing)

                {
                    ////////////////////////////////////
                    // dispose managed resources here...
                    ////////////////////////////////////

                    if (functions != null)
                        functions.Clear();
                }

                //////////////////////////////////////
                // release unmanaged resources here...
                //////////////////////////////////////

                try
                {

    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern SQLiteErrorCode sqlite3_load_extension(
        IntPtr db, byte[] fileName, byte[] procName, ref IntPtr pError);

#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl)]
#else
    [DllImport(SQLITE_DLL)]
#endif
    internal static extern SQLiteErrorCode sqlite3_overload_function(IntPtr db, IntPtr zName, int nArgs);

#if !PLATFORM_COMPACTFRAMEWORK
    [DllImport(SQLITE_DLL, CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Unicode)]
#else
    [DllImport(SQLITE_DLL, CharSet = CharSet.Unicode)]
#endif
    internal static extern SQLiteErrorCode sqlite3_win32_set_directory(uint type, string value);

###############################################################################

package require System.Data.SQLite.Test
runSQLiteTestPrologue

###############################################################################

runTest {test vtab-1.1 {basic virtual table support} -setup {
  setupDb [set fileName vtab-1.1.db]
} -body {
  set id [object invoke Interpreter.GetActive NextId]
  set dataSource [file join [getDatabaseDirectory] $fileName]

  set sql { \
    CREATE VIRTUAL TABLE t${id} USING mod${id}; \

  unset -nocomplain result code results errors sql dataSource id db fileName
} -constraints \
{eagle monoBug28 command.sql compile.DATA SQLite System.Data.SQLite\
defineConstant.System.Data.SQLite.INTEROP_VIRTUAL_TABLE} -match regexp -result \
[string map [list \n \r\n] {^Ok System#CodeDom#Compiler#CompilerResults#\d+\
\{\} 0 \{1 2 3 4 5 Error \{SQL logic error or missing database
virtual table "t\d+" is read-only\}\}$}]}

###############################################################################

runTest {test vtab-1.4 {virtual table function support} -setup {
  setupDb [set fileName vtab-1.4.db]
} -body {
  set id [object invoke Interpreter.GetActive NextId]
  set dataSource [file join [getDatabaseDirectory] $fileName]

  set sql(1) { \
    CREATE VIRTUAL TABLE t${id} USING mod${id}; \
  }

  set sql(2) { \
    SELECT Base64(x, CAST('one' AS BLOB)) FROM t${id}; \
  }

  set sql(3) { \
    SELECT Base64(x, CAST('one' AS BLOB), 'two') FROM t${id}; \
  }

  set sql(4) { \
    SELECT Base65(x, CAST('one' AS BLOB)) FROM t${id}; \
  }

  unset -nocomplain results errors

  set code [compileCSharpWith [subst {
    using System;
    using System.Data.SQLite;
    using Eagle._Containers.Public;

    namespace _Dynamic${id}
    {
      public class SQLiteFunction${id} : SQLiteFunction
      {
        public SQLiteFunction${id}()
          : base(SQLiteDateFormats.Default, DateTimeKind.Unspecified,
                 null, false)
        {
          // do nothing.
        }

        ///////////////////////////////////////////////////////////////////////

        public override object Invoke(
          object\[\] args
          )
        {
          if (args == null)
            return null;

          if (args.Length != 2)
            return new ArgumentException(String.Format(
              "need exactly two arguments, got {0}", args.Length));

          object arg = args\[1\];

          if (arg == null)
            return String.Empty;

          Type type = arg.GetType();

          if (type == typeof(DBNull))
            return String.Empty;

          if (type != typeof(byte\[\]))
            return new ArgumentException(String.Format(
              "argument must be byte array, got {0}", type));

          return Convert.ToBase64String((byte\[\]) arg);
        }
      }

      /////////////////////////////////////////////////////////////////////////

      public sealed class SQLiteModuleTest${id} : SQLiteModuleNoop
      {
        public SQLiteModuleTest${id}(string name)
          : base(name)
        {
          // do nothing.
        }

        ///////////////////////////////////////////////////////////////////////

        public override SQLiteErrorCode Create(
          SQLiteConnection connection,
          IntPtr pClientData,
          string\[\] arguments,
          ref SQLiteVirtualTable table,
          ref string error
          )
        {
          SQLiteErrorCode rc = DeclareTable(
            connection, "CREATE TABLE ignored(x);", ref error);

          if (rc != SQLiteErrorCode.Ok)
            return rc;

          rc = DeclareFunction(connection, -1, "Base64", ref error);

          if (rc != SQLiteErrorCode.Ok)
            return rc;

          table = new SQLiteVirtualTable(arguments);
          return SQLiteErrorCode.Ok;
        }

        ///////////////////////////////////////////////////////////////////////

        public override SQLiteErrorCode Open(
          SQLiteVirtualTable table,
          ref SQLiteVirtualTableCursor cursor
          )
        {
          cursor = new SQLiteVirtualTableCursor(table);
          return SQLiteErrorCode.Ok;
        }

        ///////////////////////////////////////////////////////////////////////

        public override bool FindFunction(
          SQLiteVirtualTable table,
          int argumentCount,
          string name,
          ref SQLiteFunction function,
          ref IntPtr pClientData
          )
        {
          if (argumentCount != 2)
          {
            SetTableError(table, String.Format(
              "no \\"{0}\\" functions accept {1} argument(s)",
              base.Name, argumentCount));

            return false;
          }

          if (!String.Equals(name, "Base64",
              StringComparison.OrdinalIgnoreCase))
          {
            SetTableError(table, String.Format(
              "no \\"{0}\\" functions are named \\"{1}\\"",
              base.Name, name));

            return false;
          }

          function = new SQLiteFunction${id}();
          return true;
        }
      }

      /////////////////////////////////////////////////////////////////////////

      public static class Test${id}
      {
        public static StringList GetList()
        {
          StringList result = new StringList();

          using (SQLiteConnection connection = new SQLiteConnection(
              "Data Source=${dataSource};"))
          {
            connection.Open();
            connection.CreateModule(new SQLiteModuleTest${id}("mod${id}"));

            try
            {
              using (SQLiteCommand command = connection.CreateCommand())
              {
                command.CommandText = "[subst ${sql(1)}]";
                result.Add(String.Format("{0}", command.ExecuteScalar()));
              }
            }
            catch (Exception e)
            {
              result.Add(e.Message);
            }

            try
            {
              using (SQLiteCommand command = connection.CreateCommand())
              {
                command.CommandText = "[subst ${sql(2)}]";
                result.Add(String.Format("{0}", command.ExecuteScalar()));
              }
            }
            catch (Exception e)
            {
              result.Add(e.Message);
            }

            try
            {
              using (SQLiteCommand command = connection.CreateCommand())
              {
                command.CommandText = "[subst ${sql(3)}]";
                result.Add(String.Format("{0}", command.ExecuteScalar()));
              }
            }
            catch (Exception e)
            {
              result.Add(e.Message);
            }

            try
            {
              using (SQLiteCommand command = connection.CreateCommand())
              {
                command.CommandText = "[subst ${sql(4)}]";
                result.Add(String.Format("{0}", command.ExecuteScalar()));
              }
            }
            catch (Exception e)
            {
              result.Add(e.Message);
            }

            connection.Close();
          }

          return result;
        }

        ///////////////////////////////////////////////////////////////////////

        public static void Main()
        {
          // do nothing.
        }
      }
    }
  }] true true true results errors [list System.Data.SQLite.dll Eagle.dll]]

  list $code $results \
      [expr {[info exists errors] ? $errors : ""}] \
      [expr {$code eq "Ok" ? [catch {
        object invoke _Dynamic${id}.Test${id} GetList
      } result] : [set result ""]}] $result
} -cleanup {
  cleanupDb $fileName

  unset -nocomplain result code results errors sql dataSource id db fileName
} -constraints \
{eagle monoBug28 command.sql compile.DATA SQLite System.Data.SQLite\
defineConstant.System.Data.SQLite.INTEROP_VIRTUAL_TABLE} -match regexp -result \
[string map [list \n \r\n] {^Ok System#CodeDom#Compiler#CompilerResults#\d+\
\{\} 0 \{\{\} b25l \{SQL logic error or missing database
unable to use function Base64 in the requested context\} \{SQL logic error or\
missing database
no such function: Base65\}\}$}]}

###############################################################################

runSQLiteTestEpilogue
runTestEpilogue