linkify calendar entries

app/Main.hs

@@ -10,7 +10,9 @@ import Control.Monad.Logger (runStderrLoggingT)
 import Control.Monad.Trans.Resource (runResourceT)
 import Data.ByteString.Lazy as BS
 import Data.List as List
-import Data.Time.Clock.POSIX (posixSecondsToUTCTime)
+import Data.Text as T
+import Data.Time.Clock.POSIX (posixSecondsToUTCTime, utcTimeToPOSIXSeconds)
+import Data.Time.Clock (nominalDiffTimeToSeconds)
 import Database.Persist.Postgresql (ConnectionPool, ConnectionString, SqlBackend, runMigration, runSqlPool, getPgInterval, withPostgresqlPool)
 import Debug.Trace (traceShow)
 import Session
@@ -56,6 +58,8 @@ instance YesodPersist Souplesse where
 
 getCalendarR :: Handler Html
 getCalendarR = do
+  let fTime =  T.pack . show . floor . utcTimeToPOSIXSeconds
+      fDur = T.pack . show  . ceiling . nominalDiffTimeToSeconds . getPgInterval
   (formWidget, _) <- generateFormPost uploadForm
   sessions' <- runDB Session.recents
   defaultLayout
@@ -65,8 +69,8 @@ getCalendarR = do
 <p>A calendar view goes here
 <ul>
     $forall s <- sessions'
-        <li>#{show $ sessionStartTime s}  #{show $ getPgInterval (sessionDuration s)}
-
+        <li>
+             <a href=@?{(TimelineR, [("start", fTime $ sessionStartTime s), ("duration", fDur $ sessionDuration s)])} > #{show $ sessionStartTime s} #{show $ getPgInterval (sessionDuration s)}
 
 <form action="/upload" method=post enctype="multipart/form-data">
     ^{formWidget}