saga: Build on darwin

There are some unresolved dependency issues which means a lot of
additional dependencies have to be added explicitly on darwin but not on
linux. Maybe something to do with libtool.

See https://groups.google.com/forum/#!topic/nix-devel/h_vSzEJAPXs

pkgs/applications/gis/saga/default.nix

@@ -1,10 +1,15 @@
 { stdenv, fetchurl, gdal, wxGTK30, proj, libiodbc, lzma, jasper,
-  libharu, opencv, vigra, postgresql }:
+  libharu, opencv, vigra, postgresql, Cocoa,
+  unixODBC , poppler, hdf4, hdf5, netcdf, sqlite }:
 
 stdenv.mkDerivation rec {
   name = "saga-6.3.0";
 
-  buildInputs = [ gdal wxGTK30 proj libharu opencv vigra postgresql libiodbc lzma jasper ];
+  # See https://groups.google.com/forum/#!topic/nix-devel/h_vSzEJAPXs
+  # for why the have additional buildInputs on darwin
+  buildInputs = [ gdal wxGTK30 proj libharu opencv vigra postgresql libiodbc lzma jasper ]
+                ++ stdenv.lib.optionals stdenv.isDarwin
+                  [ Cocoa unixODBC poppler hdf4.out hdf5 netcdf sqlite ];
 
   enableParallelBuilding = true;
 
@@ -13,11 +18,11 @@ stdenv.mkDerivation rec {
     sha256 = "0hyjim8fcp3mna1hig22nnn4ki3j6b7096am2amcs99sdr09jjxv";
   };
 
-  meta = {
+  meta = with stdenv.lib; {
     description = "System for Automated Geoscientific Analyses";
     homepage = http://www.saga-gis.org;
-    license = stdenv.lib.licenses.gpl2Plus;
-    maintainers = [ stdenv.lib.maintainers.michelk ];
-    platforms = ["x86_64-linux" ];
+    license = licenses.gpl2Plus;
+    maintainers = [ maintainers.michelk ];
+    platforms = with platforms; unix;
   };
 }

pkgs/top-level/all-packages.nix

@@ -19878,6 +19878,10 @@ with pkgs;
 
   saga = callPackage ../applications/gis/saga { };
 
+  saga = callPackage ../applications/gis/saga {
+    inherit (darwin.apple_sdk.frameworks) Cocoa;
+  };
+
   samplv1 = callPackage ../applications/audio/samplv1 { };
 
   sauerbraten = callPackage ../games/sauerbraten {};