From e2d128cceaf20367079b0c22d27d47d2db3a58f8 Mon Sep 17 00:00:00 2001
From: "Harry T. Vennik" <htvennik@gmail.com>
Date: Mon, 17 Jul 2017 20:54:35 +0200
Subject: [PATCH] Added support for BitFlags

---
 source/ddbus/conv.d | 23 ++++++++++++++++++++++-
 source/ddbus/util.d |  9 +++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/source/ddbus/conv.d b/source/ddbus/conv.d
index 85c5369..3b49e0e 100644
--- a/source/ddbus/conv.d
+++ b/source/ddbus/conv.d
@@ -132,7 +132,24 @@ T readIter(T)(DBusMessageIter *iter) if (is(T == enum)) {
   return cast(T) value;
 }
 
-T readIter(T)(DBusMessageIter *iter) if (!is(T == enum) && canDBus!T) {
+T readIter(T)(DBusMessageIter *iter) if (isInstanceOf!(BitFlags, T)) {
+  import std.algorithm.iteration : fold;
+
+  alias TemplateArgsOf!T[0] E;
+  alias OriginalType!E B;
+
+  B mask = only(EnumMembers!E).fold!((a, b) => a | b);
+
+  B value = readIter!B(iter);
+  enforce(
+    !(value & ~mask),
+    new InvalidValueException(value, T.stringof)
+  );
+
+  return T(cast(E) value);
+}
+
+T readIter(T)(DBusMessageIter *iter) if (!is(T == enum) && !isInstanceOf!(BitFlags, T) && canDBus!T) {
   T ret;
 
   static if(!isVariant!T || is(T == Variant!DBusAny)) {
@@ -331,6 +348,10 @@ unittest {
   readIter!E(&iter).assertEqual(E.c);
   readIter!E(&iter).assertThrow!InvalidValueException();
 
+  iter2 = iter;
   readIter!F(&iter).assertThrow!InvalidValueException();
+  readIter!(BitFlags!F)(&iter2).assertEqual(BitFlags!F(F.x, F.z));
+
   readIter!F(&iter).assertThrow!InvalidValueException();
+  readIter!(BitFlags!F)(&iter2).assertThrow!InvalidValueException();
 }
diff --git a/source/ddbus/util.d b/source/ddbus/util.d
index 320a55c..968e89a 100644
--- a/source/ddbus/util.d
+++ b/source/ddbus/util.d
@@ -49,6 +49,9 @@ template basicDBus(T) {
     enum basicDBus = true;
   } else static if(is(T B == enum)) {
     enum basicDBus = basicDBus!B;
+  } else static if(isInstanceOf!(BitFlags, T)) {
+    alias TemplateArgsOf!T[0] E;
+    enum basicDBus = basicDBus!E;
   } else {
     enum basicDBus = false;
   }
@@ -111,6 +114,9 @@ string typeSig(T)() if(canDBus!T) {
     return "v";
   } else static if(is(T B == enum)) {
     return typeSig!B;
+  } else static if(isInstanceOf!(BitFlags, T)) {
+    alias TemplateArgsOf!T[0] E;
+    return typeSig!E;
   } else static if(is(T == DBusAny)) {
     static assert(false, "Cannot determine type signature of DBusAny. Change to Variant!DBusAny if a variant was desired.");
   } else static if(isTuple!T) {
@@ -179,6 +185,9 @@ unittest {
   typeSig!E().assertEqual(typeSig!byte());
   enum U : string { One = "One", Two = "Two" }
   typeSig!U().assertEqual(typeSig!string());
+  // bit flags
+  enum F : uint { a = 1, b = 2, c = 4 }
+  typeSig!(BitFlags!F)().assertEqual(typeSig!uint());
   // structs
   typeSig!(Tuple!(int,string,string)).assertEqual("(iss)");
   typeSig!(Tuple!(int,string,Variant!int,Tuple!(int,"k",double,"x"))).assertEqual("(isv(id))");