From 388a2fe65993311d4b4d4ba1903cfc26468b588a Mon Sep 17 00:00:00 2001
From: Stephan Sundermann <stephansundermann@gmail.com>
Date: Wed, 9 Oct 2013 15:31:10 +0200
Subject: [PATCH] generator: added handling of optional parameters

---
 generator/Method.cs     | 11 +++++++++++
 generator/Parameter.cs  |  6 ++++++
 generator/Parameters.cs |  8 ++++++++
 generator/Signature.cs  | 38 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 63 insertions(+)

diff --git a/generator/Method.cs b/generator/Method.cs
index 59711bfe6..14cb56a6f 100644
--- a/generator/Method.cs
+++ b/generator/Method.cs
@@ -207,6 +207,14 @@ namespace GtkSharp.Generation {
 			}
 		}
 
+		public void GenerateOverloads (StreamWriter sw)
+		{
+			sw.WriteLine ();
+			sw.WriteLine ("\t\t" + retval.CSType + " " + Name + "(" + (Signature != null ? Signature.WithoutOptional () : "") + ") {");
+			sw.WriteLine ("\t\t\t{0}{1} ({2});", !retval.IsVoid ? "return " : String.Empty, Name, Signature.CallWithoutOptionals ());
+			sw.WriteLine ("\t\t}");
+		}
+
 		public void Generate (GenerationInfo gen_info, ClassBase implementor)
 		{
 			Method comp = null;
@@ -266,6 +274,9 @@ namespace GtkSharp.Generation {
 			}
 			else
 				gen_info.Writer.WriteLine();
+
+			if (Parameters.HasOptional && !(is_get || is_set))
+				GenerateOverloads (gen_info.Writer);
 			
 			gen_info.Writer.WriteLine();
 
diff --git a/generator/Parameter.cs b/generator/Parameter.cs
index 1344ea102..31d2063f0 100644
--- a/generator/Parameter.cs
+++ b/generator/Parameter.cs
@@ -90,6 +90,12 @@ namespace GtkSharp.Generation {
 			}
 		}
 
+		internal bool IsOptional {
+			get {
+				return elem.GetAttributeAsBoolean ("allow-none");
+			}
+		}
+
 		bool is_count;
 		bool is_count_set;
 		public bool IsCount {
diff --git a/generator/Parameters.cs b/generator/Parameters.cs
index ae953ab7e..067fd8801 100644
--- a/generator/Parameters.cs
+++ b/generator/Parameters.cs
@@ -142,6 +142,11 @@ namespace GtkSharp.Generation {
 			set { is_static = value; }
 		}
 
+		bool has_optional;
+		internal bool HasOptional {
+			get { return has_optional;}
+		}
+
 		public Parameter GetCountParameter (string param_name)
 		{
 			foreach (Parameter p in this)
@@ -198,6 +203,9 @@ namespace GtkSharp.Generation {
 					return false;
 				}
 
+				if (p.IsOptional && p.PassAs == String.Empty)
+					has_optional = true;
+
 				IGeneratable gen = p.Generatable;
 
 				if (p.IsArray) {
diff --git a/generator/Signature.cs b/generator/Signature.cs
index 80808ddd3..9c2683ce7 100644
--- a/generator/Signature.cs
+++ b/generator/Signature.cs
@@ -118,6 +118,44 @@ namespace GtkSharp.Generation {
 				return String.Join (", ", result);
 			}
 		}
+
+		public string WithoutOptional ()
+		{
+			if (parms.Count == 0)
+				return String.Empty;
+
+			var result = new string [parms.Count];
+			int i = 0;
+
+			foreach (Parameter p in parms) {
+				if (p.IsOptional && p.PassAs == String.Empty)
+					continue;
+				result [i] = p.PassAs != String.Empty ? p.PassAs + " " : String.Empty;
+				result [i++] += p.CSType + " " + p.Name;
+			}
+
+			return String.Join (", ", result, 0, i);
+		}
+
+		public string CallWithoutOptionals ()
+		{
+			if (parms.Count == 0)
+				return String.Empty;
+
+			var result = new string [parms.Count];
+			int i = 0;
+
+			foreach (Parameter p in parms) {
+
+				result [i] = p.PassAs != "" ? p.PassAs + " " : "";
+				if (p.IsOptional && p.PassAs == String.Empty)
+					result [i++] += (p.Generatable is StructGen || p.Generatable is BoxedGen) ? (p.CSType + ".Zero") : "null";
+				else
+					result [i++] += p.Name;
+			}
+
+			return String.Join (", ", result);
+		}
 	}
 }