1 files changed, 67 insertions, 0 deletions
diff --git a/cli/Main.hs b/cli/Main.hs
new file mode 100644
index 0000000..2c7aa7d
--- /dev/null
+++ b/cli/Main.hs
@@ -0,0 +1,67 @@
+import Math
+import System.Environment
+import Data.List
+import Text.Printf
+
+errorMessage :: String -> String
+
+errorMessage "" = "nd v1\nUsage: nd [-help, -int, -prime, -factor, -hcf]\n"
+errorMessage reason = "nd v1\nFAILURE: "
+                        ++ reason
+                        ++ "\nUsage: nd [-int, -prime, -factor, -hcf]\n"
+
+flagHandlerF :: [String] -> Int -> String -> ([String] -> String) -> String
+
+flagHandlerF args (-1) error fmessage =
+  if (length args) == 0
+  then error
+  else fmessage args
+
+flagHandlerF args nargs error fmessage =
+  if (length args) /= nargs
+  then error
+  else fmessage args
+
+flagHandler :: String -> [String] -> String
+
+flagHandler "-prime" args =
+  flagHandlerF args (-1)
+    (errorMessage "-prime requires at least one integer argument")
+    (\args ->
+        foldl (++) "" [show y ++ ": isPrime=" ++ (show $ isPrime y)
+                    ++ "\n" | x <- args, let y = (read x) :: Int])
+
+flagHandler "-factor" args =
+  flagHandlerF args (-1)
+    (errorMessage "-factor requires at least one integer argument")
+    (\args ->
+        foldl (++) "" [show y ++ ": factors=" ++ show (factors $ y)
+                        | x <- args, let y = (read x) :: Int])
+
+flagHandler "-int" args =
+  flagHandlerF args (-1)
+    (errorMessage "-int requires at least one integer argument")
+    (\args ->
+        foldl (++) "" [show y ++ ": (isPrime=" ++ (show $ isPrime y)
+                        ++ ", factors=" ++ (show $ factors y)
+                        ++ ")\n" | x <- args, let y = (read x) :: Int])
+
+flagHandler "-hcf" args =
+  flagHandlerF args (2)
+    (errorMessage "-hcf requires two integer arguments")
+    (\args ->
+        let n       = (read $ head args) :: Int
+            m       = (read $ head $ tail args) :: Int
+            hcf     = head $ reverse $ intersect (factors n) (factors m) in
+        "hcf(" ++ show n ++ ", " ++ show m ++ "): hcf=" ++ show hcf)
+
+flagHandler _ _ =
+  errorMessage "Flag not recognised"
+
+
+main = do
+  args <- getArgs
+  putStr $
+    case args of
+        []      -> errorMessage ""
+        (x: xs) -> if x == "-help" then errorMessage "" else flagHandler x xs