Added help text

1 files changed, 55 insertions, 21 deletions

diff --git a/clpm.icl b/clpm.icl
index ad627fa..26b98f4 100644
--- a/clpm.icl
+++ b/clpm.icl
@@ -1,5 +1,6 @@
 module clpm
 
+import _SystemArray
 from StdFunc import flip, o
 import StdFile
 import StdList
@@ -26,6 +27,8 @@ import System.File
 import CLPM.Package
 import CLPM.Repository
 
+CLPM_VERSION :== (0,1,0)
+
 :: Action
 	= NoAction
 	| Install
@@ -36,24 +39,27 @@ import CLPM.Repository
 	  , action       :: Action
 	  , repository   :: String
 	  , clm_options  :: [String]
+	  , show_help    :: Bool
 	  }
 
 instance zero Arguments
 where
 	zero
 		= { package_file = PACKAGE_FILE
-		  , action = NoAction
-		  , repository = REPOSITORY
-		  , clm_options = []
+		  , action       = NoAction
+		  , repository   = REPOSITORY
+		  , clm_options  = []
+		  , show_help    = False
 		  }
 
 Start w
 # (io,w) = stdio w
-# ((missed, args), w) = appFst (parseArgs [] zero o tl) $ getCommandLine w
+# ((missed, args), w) = appFst (parseArgs zero o tl) $ getCommandLine w
 | not (isEmpty missed)
 	# io = foldr (flip (<<<)) io ["Unknown option: " + m + "\n" \\ m <- missed]
-	# (_,w) = fclose io w
-	= w
+	= snd $ fclose io w
+| args.show_help
+	= snd $ fclose (io <<< HELP_TEXT) w
 # (pkg,w) = readPackage args.package_file w
 | isError pkg
 	# io = io <<< fromError pkg <<< "\n"
@@ -106,23 +112,51 @@ make opts pkg io w
 	" " + pkg.main + " -o " + pkg.main) w
 = (io,w)
 
-parseArgs :: [String] Arguments [String] -> ([String], Arguments)
-parseArgs miss args []
-	= (miss, args)
-parseArgs miss args ["-p":name:rest]
-	= parseArgs miss {args & package_file = name} rest
-parseArgs miss args ["-r":repo:rest]
-	= parseArgs miss {args & repository = repo} rest
-parseArgs miss args ["-c":opt:rest]
-	= parseArgs miss {args & clm_options = args.clm_options ++ [opt]} rest
-parseArgs miss args ["install":rest]
-	= parseArgs miss {args & action = Install} rest
-parseArgs miss args ["make":rest]
-	= parseArgs miss {args & action = Make} rest
-parseArgs miss args [a:rest]
-	= parseArgs [a:miss] args rest
+parseArgs :: (Arguments [String] -> ([String], Arguments))
+parseArgs = pa []
+where
+	pa :: [String] Arguments [String] -> ([String], Arguments)
+	pa miss args []               = (miss, args)
+	pa miss args ["-h":rest]      = pa miss {args & show_help = True} rest
+	pa miss args ["--help":rest]  = pa miss {args & show_help = True} rest
+	pa miss args ["-p":name:rest] = pa miss {args & package_file = name} rest
+	pa miss args ["-r":repo:rest] = pa miss {args & repository = repo} rest
+	pa miss args ["-c":opt:rest]  = pa miss {args & clm_options = args.clm_options ++ [opt]} rest
+	pa miss args ["install":rest] = pa miss {args & action = Install} rest
+	pa miss args ["make":rest]    = pa miss {args & action = Make} rest
+	pa miss args [a:rest]         = pa [a:miss] args rest
 
 syscall :: !String !*World -> !*(!Int, !*World)
 syscall cmd w = code {
 	ccall system "s:I:A"
 }
+
+HELP_TEXT =:
+	"CLPM - A Clean Package Manager - v" + toString CLPM_VERSION + "\r\n\r\n" +
+	"Usage: clpm <command> [option]\r\n\r\n" +
+	foldl (+) "Commands:\r\n"
+		[pad 2 12 cmd + desc + "\r\n" \\ (cmd,desc) <- cmds] + "\r\n" +
+	foldl (+) "Options:\r\n"
+		[pad 2 12 opt + desc + "\r\n" \\ (opt,desc) <- opts]
+where
+	cmds =
+		[ ("make",    "Build package using clm")
+		, ("install", "Install package dependencies")
+		]
+
+	opts =
+		[ ("-c <OPT>",
+		  "Add OPT to the clm arguments")
+		, ("-h, --help",
+		  "Print this help text")
+		, ("-p <FILE>",
+		  "Use FILE as package file instead of package.json")
+		, ("-r <HOST>",
+		  "Use HOST as repository provider instead of " + REPOSITORY)
+		]
+
+	pad :: Int Int String -> String
+	pad l r s
+	| size s > r = p l + s + "\r\n" + p (l + r)
+	| otherwise  = p l + s + p (r - size s)
+	where p i = toString $ repeatn i ' '