4 files changed, 78 insertions, 3 deletions

diff --git a/events/events.cabal b/events/events.cabal
index 796742e..3e784af 100644
--- a/events/events.cabal
+++ b/events/events.cabal
@@ -20,6 +20,15 @@ executable events
   main-is:             Main.hs
   -- other-modules:       
   -- other-extensions:    
-  build-depends:       base >=4.8 && <4.9
+  build-depends:       base >=4.8 && <5
+                     , lens >=4.13 && <5
+                     , tz >=0.1 && <1
+                     , time >=1.5.0 && <2
+                     , lens-time >=0.1 && <1
+                     , aeson >=0.9 && <1
+                     , aeson-lens >=0.5 && <1
+                     , mtl >=2.2 && <3
+                     , list-t >=0.4.6 && <1
+                     , data-default-class >=0.0 && <1
   hs-source-dirs:      src
   default-language:    Haskell2010
\ No newline at end of file
diff --git a/events/events.nix b/events/events.nix
index dba4055..458e78a 100644
--- a/events/events.nix
+++ b/events/events.nix
@@ -1,11 +1,16 @@
-{ mkDerivation, base, stdenv }:
+{ mkDerivation, aeson, aeson-lens, base, data-default-class, lens
+, lens-time, list-t, mtl, stdenv, time, tz
+}:
 mkDerivation {
   pname = "events";
   version = "0.0.0";
   src = ./.;
   isLibrary = false;
   isExecutable = true;
-  executableHaskellDepends = [ base ];
+  executableHaskellDepends = [
+    aeson aeson-lens base data-default-class lens lens-time list-t mtl
+    time tz
+  ];
   homepage = "https://git.yggdrasil.li/gkleen/pub/events";
   description = "An appointment book";
   license = stdenv.lib.licenses.mit;
diff --git a/events/src/Events/Types.hs b/events/src/Events/Types.hs
new file mode 100644
index 0000000..55e7a5a
--- /dev/null
+++ b/events/src/Events/Types.hs
@@ -0,0 +1,59 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+module Events.Types
+       ( TimeRange(..), rangeStart, rangeDuration
+       , Event(..), payload, occursWithin
+       , SpecCtx(..), ctxVars
+       , Spec
+       , module Data.Aeson
+       , module Data.Time.Clock
+       , module Data.Default.Class
+       ) where
+
+import Control.Lens.TH
+  
+import Data.Aeson (Object)
+
+import Data.Time.Clock
+
+import Control.Monad.Reader
+import ListT (ListT)
+import qualified ListT as ListT
+
+import Data.Default.Class
+
+import Data.Monoid
+import Control.Monad.Fix
+import Control.Lens
+import Data.Maybe
+
+data TimeRange = TimeRange
+                 { _rangeStart :: UTCTime
+                 , _rangeDuration :: NominalDiffTime
+                 }
+makeLenses ''TimeRange
+
+data Event = Event
+             { _payload :: Object
+             , _occursWithin :: TimeRange -> Bool
+             }
+makeLenses ''Event
+
+data SpecCtx = SpecCtx
+               { _ctxVars :: Object
+               , _ctxEvents :: [Event]
+               }
+makeLenses ''SpecCtx
+
+instance Default SpecCtx where
+  def = SpecCtx
+        { _ctxVars = mempty
+        , _ctxEvents = mempty
+        }
+
+type Spec m a = ListT (ReaderT SpecCtx m) a
+
+interpret :: MonadFix m => Spec m (Maybe Event) -> m [Event]
+interpret x = catMaybes <$> mfix x'
+  where
+    x' = runReaderT (ListT.toList x) . flip (set ctxEvents) def . catMaybes
diff --git a/events/src/Main.hs b/events/src/Main.hs
index e9e1deb..1c56140 100644
--- a/events/src/Main.hs
+++ b/events/src/Main.hs
@@ -1,2 +1,4 @@
+import Events.Types
+
 main :: IO ()
 main = undefined