protected virtual string ParseInvoke( DynamicNode.Invoke node, KParameterList pars = null )
{
// This is used as an especial syntax to merely concatenate its arguments separated by spaces if needed...
// It is used as a way to extend the supported syntax without the need of treating all the possible cases...
if( node.Arguments == null ) return string.Empty;
if( node.Arguments.Length == 0 ) return string.Empty;
StringBuilder sb = new StringBuilder();
bool first = true;
foreach( object arg in node.Arguments ) {
if( !first ) {
bool space = true;
if( ( arg is string ) && ( (string)arg ).StartsWith( " " ) ) space = false;
if( space ) sb.Append( " " );
}
else first = false;
if( arg is string ) sb.Append( (string)arg );
else sb.Append( Parse( arg, pars, rawstr: true, nulls: true ) );
}
return sb.ToString();
}
protected virtual string ParseConvert( DynamicNode.Convert node, KParameterList pars = null )
{
DEBUG.WriteLine( "\n-- PENDING: KParser.ParseConvert() requires an override..." );
string r = Parse( node.SourceNode, pars );
return r;
}
protected virtual string ParseBinary( DynamicNode.Binary node, KParameterList pars = null )
{
string op = ""; switch( node.Operation ) {
case ExpressionType.Add: op = "+"; break;
case ExpressionType.Subtract: op = "-"; break;
case ExpressionType.Multiply: op = "*"; break;
case ExpressionType.Divide: op = "/"; break;
case ExpressionType.Modulo: op = "%"; break;
case ExpressionType.Power: op = "^"; break;
case ExpressionType.And: op = "AND"; break;
case ExpressionType.Or: op = "OR"; break;
// Treating NULL targets as special cases...
case ExpressionType.Equal: op = node.Right == null ? "IS" : "="; break;
case ExpressionType.NotEqual: op = node.Right == null ? "IS NOT" : "!="; break;
case ExpressionType.GreaterThan: op = ">"; break;
case ExpressionType.GreaterThanOrEqual: op = ">="; break;
case ExpressionType.LessThan: op = "<"; break;
case ExpressionType.LessThanOrEqual: op = "<="; break;
default: throw new ArgumentException( "Not supported operator: '" + node.Operation + "'." );
}
string left = Parse( node.Left, pars ); // Not nulls: left is assumed to be an object
string right = Parse( node.Right, pars, nulls: true );
return string.Format( "( {0} {1} {2} )", left, op, right );
}
protected virtual string ParseMethod( DynamicNode.Method node, KParameterList pars = null )
{
string parent = Parse( node.Host, pars );
string method = node.Name.ToUpper();
string item = null;
// ROOT-LEVEL...
if( parent == null ) {
switch( method ) {
case "NOT":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "NOT operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "( NOT {0} )", item );
}
}
// COLUMN-LEVEL...
else {
switch( method ) {
case "IN":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "IN operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "{0} IN ( {1} )", parent, item );
case "AS":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "AS operator expects one argument." );
item = Parse( node.Arguments[0], null, rawstr: true ); // pars=null to avoid parametrize aliases
item = item.Validated( "Alias", invalidChars: TypeHelper.InvalidNameChars );
return string.Format( "{0} AS {1}", parent, item );
}
}
// DEFAULT-CASE...
method = parent == null ? node.Name : string.Format( "{0}.{1}", parent, node.Name );
StringBuilder sb = new StringBuilder();
sb.AppendFormat( "{0}(", method ); if( node.Arguments != null && node.Arguments.Length != 0 ) {
sb.Append( " " );
bool first = true; foreach( object argument in node.Arguments ) {
if( !first ) sb.Append( ", " ); else first = false;
sb.Append( Parse( argument, pars, nulls: true ) ); // We don't accept raw strings here!!!
}
sb.Append( " " );
}
sb.Append( ")" );
return sb.ToString();
}
protected virtual string ParseSetMember( DynamicNode.SetMember node, KParameterList pars = null )
{
string parent = Parse( node.Host, pars );
string name = parent == null ? node.Name : string.Format( "{0}.{1}", parent, node.Name );
string value = Parse( node.Value, pars, nulls: true );
return string.Format( "{0} = ( {1} )", name, value );
}
protected virtual string ParseUnary( DynamicNode.Unary node, KParameterList pars = null )
{
switch( node.Operation ) {
// Artifacts from the DynamicParser class that are not usefull here...
case ExpressionType.IsFalse:
case ExpressionType.IsTrue: return Parse( node.Target, pars );
// Unary supported operations...
case ExpressionType.Not: return string.Format( "( NOT {0} )", Parse( node.Target, pars ) );
case ExpressionType.Negate: return string.Format( "!( {0} )", Parse( node.Target, pars ) );
}
throw new ArgumentException( "Not supported unary operation: " + node );
}
protected virtual string ParseCommand( IKCommand node, KParameterList pars = null )
{
// Getting the command's text...
string str = node.CommandText( iterable: false ); // Avoiding spurious "OUTPUT XXX" statements
// If there are parameters to transform, but cannot store them, it is an error
if( node.Parameters.Count != 0 && pars == null )
throw new InvalidOperationException( "Cannot parse IKCommand because the receiving parameters collection is null." );
// Transforming the parameters using names compatible with this command string and context
foreach( var parameter in node.Parameters ) {
KParameter neo = pars.Insert( parameter.Value );
str = str.Replace( parameter.Name, neo.Name );
}
return str;
}
protected virtual string ParseGetMember( DynamicNode.GetMember node, KParameterList pars = null )
{
string parent = Parse( node.Host, pars );
string name = parent == null ? node.Name : string.Format( "{0}.{1}", parent, node.Name );
return name;
}
string Dispatch( object node, KParameterList pars = null )
{
if( node != null ) {
// Flag to indicate the root of a dynamic argument...
if( node.GetType() == typeof( DynamicNode.Argument ) ) return null;
// Other node types and elements to parse...
else if( node is IKCommand ) return ParseCommand( (IKCommand)node, pars );
else if( node is DynamicNode.GetMember ) return ParseGetMember( (DynamicNode.GetMember)node, pars );
else if( node is DynamicNode.SetMember ) return ParseSetMember( (DynamicNode.SetMember)node, pars );
else if( node is DynamicNode.Unary ) return ParseUnary( (DynamicNode.Unary)node, pars );
else if( node is DynamicNode.Binary ) return ParseBinary( (DynamicNode.Binary)node, pars );
else if( node is DynamicNode.Method ) return ParseMethod( (DynamicNode.Method)node, pars );
else if( node is DynamicNode.Invoke ) return ParseInvoke( (DynamicNode.Invoke)node, pars );
else if( node is DynamicNode.Convert ) return ParseConvert( (DynamicNode.Convert)node, pars );
}
// All other cases are considered constant parameters...
return ParseConstant( node, pars );
}
protected virtual string ParseConstant( object node, KParameterList pars = null )
{
if( node == null ) return ParseNull();
if( pars != null ) { // If we have a list of parameters to store it, let's parametrize it
var par = pars.Insert( node );
return par.Name;
}
return node.ToString(); // Last resort case
}
/// <summary>
/// Parsers the given node and returns a string with its contents translated.
/// <para>The node is typically a dynamic lambda expression, but can also be any valid C# object.</para>
/// <para>In this case, typically a new parameter is created to contain its value, who is stored in the parameter
/// list given (if it is not null), and the parameter's name is placed into the returned string.</para>
/// </summary>
/// <param name="node">The object to parse.</param>
/// <param name="pars">The parameters list where to store the parameters created.</param>
/// <param name="rawstr">If raw strings are considered valid, or not acceptable.</param>
/// <param name="nulls">If null nodes are considered valid, or not acceptable.</param>
/// <returns>The parsed string.</returns>
public virtual string Parse( object node, KParameterList pars = null, bool rawstr = false, bool nulls = false )
{
// Null nodes are accepted or not depending upon the "nulls" flag...
if( node == null ) {
if( !nulls ) throw new ArgumentNullException( "node", "Null nodes are not accepted." );
return Dispatch( node, pars );
}
// Nodes that are strings are parametrized or not depending the "rawstr" flag...
if( node is string ) {
if( rawstr ) return (string)node;
else return Dispatch( node, pars );
}
// If node is a delegate, parse it to create the logical tree...
if( node is Delegate ) {
node = DynamicParser.Parse( (Delegate)node ).Result;
return Parse( node, pars, rawstr ); // Intercept containers as in (x => "string")
}
return Dispatch( node, pars );
}
protected virtual void Dispose( bool disposing )
{
DEBUG.IndentLine( "\n-- KCommand.Dispose( Disposing={0} ) - This={1}", disposing, this );
if( _Parameters != null ) { _Parameters.Dispose(); _Parameters = null; }
if( _Parser != null ) { _Parser.Dispose(); _Parser = null; }
_Link = null;
DEBUG.Unindent();
}
/// <summary>
/// Creates a new <see cref="KCommand"/> associated with the given link.
/// </summary>
/// <param name="link">The link this command is associated with.</param>
protected KCommand( IKLink link )
{
DEBUG.IndentLine( "\n-- KCommand( Link={0} )", link == null ? "null" : link.ToString() );
if( ( _Link = link ) == null ) throw new ArgumentNullException( "link", "Link cannot be null." );
if( ( _Parameters = _Link.Factory.CreateParameterList() ) == null ) throw new InvalidOperationException( "Cannot create a List of Parameters." );
if( ( _Parser = _Link.Factory.CreateParser() ) == null ) throw new InvalidOperationException( "Cannot create a Parser." );
DEBUG.Unindent();
}
/// <summary>
/// Creates a new executor for the command specified by its text and parameters.
/// </summary>
/// <param name="text">The text of the non-query command.</param>
/// <param name="pars">The arguments of the command.</param>
/// <returns>The unique Guid identifying the new created executor.</returns>
public virtual Guid ExecutorCreate( string text, KParameterList pars )
{
DEBUG.IndentLine( "\n-- [{0}] KServerWCF.ExecutorCreate( {1}{2} )", _ProxyId.TagString(),
text ?? "<null>",
pars == null ? "" : string.Format( " - {0}", pars ) );
try {
if( _Link == null ) throw new InvalidOperationException( "WCF Server is not yet connected." );
text = text.Validated( "Command Text" );
IKCommandExecutable cmd = _Link.Raw( text );
if( pars != null ) foreach( var par in pars ) cmd.Parameters.Add( par.Clone() );
IKExecutor executor = cmd.GetExecutor();
if( executor == null ) throw new InvalidOperationException( "Cannot create Executor for command: " + cmd.TraceString() );
Guid uid = Guid.NewGuid();
_Elements.Add( uid, executor );
DEBUG.WriteLine( "\n-- Executor created with UID = {0}", uid.TagString() );
return uid;
}
catch( Exception e ) { DEBUG.PrintException( e ); throw; }
finally { DEBUG.Unindent(); }
}
protected override string ParseMethod( DynamicNode.Method node, KParameterList pars )
{
string host = Parse( node.Host, pars );
string name = node.Name.ToUpper();
string item = null;
string alias = null;
string extra = null;
// ROOT-LEVEL...
if( host == null ) {
switch( name ) {
case "CAST":
if( node.Arguments == null || node.Arguments.Length != 2 ) throw new ArgumentException( "CAST operator expects two arguments." );
item = Parse( node.Arguments[0], pars ); // No raw strings
alias = Parse( node.Arguments[1], null, rawstr: true ); // pars=null to avoid parametrize aliases
alias = alias.Validated( "Alias", invalidChars: TypeHelper.InvalidNameChars );
return string.Format( "CAST( {0} AS {1} )", item, alias );
}
}
// COLUMN-LEVEL...
else {
switch( name ) {
case "LEFT":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "LEFT operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "LEFT( {0}, {1} )", host, item );
case "RIGHT":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "RIGHT operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "RIGHT( {0}, {1} )", host, item );
case "LEN":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "LEN operator does not expect any arguments." );
return string.Format( "LEN( {0} )", host );
case "LOWER":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "LOWER operator does not expect any arguments." );
return string.Format( "LOWER( {0} )", host );
case "UPPER":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "UPPER operator does not expect any arguments." );
return string.Format( "UPPER( {0} )", host );
case "YEAR":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "YEAR operator does not expect any arguments." );
return string.Format( "DATEPART( YEAR, {0} )", host );
case "MONTH":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "MONTH operator does not expect any arguments." );
return string.Format( "DATEPART( MONTH, {0} )", host );
case "DAY":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "DAY operator does not expect any arguments." );
return string.Format( "DATEPART( DAY, {0} )", host );
case "HOUR":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "HOUR operator does not expect any arguments." );
return string.Format( "DATEPART( HOUR, {0} )", host );
case "MINUTE":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "MINUTE operator does not expect any arguments." );
return string.Format( "DATEPART( MINUTE, {0} )", host );
case "SECOND":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "SECOND operator does not expect any arguments." );
return string.Format( "DATEPART( SECOND, {0} )", host );
case "MILLISECOND":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "MILLISECOND operator does not expect any arguments." );
return string.Format( "DATEPART( MILLISECOND, {0} )", host );
case "OFFSET":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "OFFSET operator does not expect any arguments." );
return string.Format( "DATEPART( TZ, {0} )", host );
case "LIKE":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "LIKE operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "( {0} LIKE {1} )", host, item );
case "NOTLIKE":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "NOT LIKE operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "( {0} NOT LIKE {1} )", host, item );
case "CONTAINS":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "CONTAINS operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "CONTAINS( {0}, {1} )", host, item );
case "PATINDEX":
if( node.Arguments == null || node.Arguments.Length != 1 ) throw new ArgumentException( "PATINDEX operator expects one argument." );
item = Parse( node.Arguments[0], pars );
return string.Format( "PATINDEX( {1}, {0} )", host, item ); // Note {0} and {1} are reversed
case "SUBSTRING":
if( node.Arguments == null || node.Arguments.Length != 2 ) throw new ArgumentException( "SUBSTRING operator expects two arguments." );
item = Parse( node.Arguments[0], pars );
extra = Parse( node.Arguments[1], pars );
return string.Format( "SUBSTRING( {0}, {1}, {2} )", host, item, extra );
case "LTRIM":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "LTRIM operator does not expect any arguments." );
return string.Format( "LTRIM( {0} )", host );
case "RTRIM":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "RTRIM operator does not expect any arguments." );
return string.Format( "RTRIM( {0} )", host );
case "TRIM":
if( node.Arguments != null && node.Arguments.Length != 0 ) throw new ArgumentException( "TRIM operator does not expect any arguments." );
return string.Format( "LTRIM( RTRIM( {0} ) )", host );
}
}
// DEFAULT case...
return base.ParseMethod( node, pars );
}
