init dfetch for system queries

1 files changed, 26 insertions, 0 deletions

diff --git a/packages/code/dfetch/app/Dfetch/Battery.hs b/packages/code/dfetch/app/Dfetch/Battery.hs
new file mode 100644
index 0000000..6e6a0a8
--- /dev/null
+++ b/packages/code/dfetch/app/Dfetch/Battery.hs
@@ -0,0 +1,26 @@
+module Dfetch.Battery
+  ( Battery(..)
+  , allBatteries
+  ) where
+
+import System.FilePath ((</>))
+import System.Directory (listDirectory)
+import Data.List (isPrefixOf)
+
+basePath :: FilePath
+basePath = "/sys/class/power_supply/"
+
+data Battery = Battery
+  {name :: String, capacity :: Int} deriving (Show)
+
+getCapacity :: String -> IO Battery
+getCapacity name = Battery <$> pure name <*> capacity
+  where
+    path = basePath </> name </> "capacity"
+    capacity = read <$> readFile path
+
+findBatteries :: IO [String]
+findBatteries = filter ("BAT" `isPrefixOf`) <$> listDirectory basePath
+
+allBatteries :: IO [Battery]
+allBatteries = findBatteries >>= traverse getCapacity