git-annex/Usage.hs

{- git-annex usage messages
 -
 - Copyright 2010-2011 Joey Hess <joey@kitenet.net>
 -
 - Licensed under the GNU GPL version 3 or higher.
 -}

module Usage where

import Common.Annex
import System.Console.GetOpt

import Types.Command

{- Usage message with lists of commands and options. -}
usage :: String -> [Command] -> [Option] -> String
usage header cmds commonoptions = unlines $ 
	[ header
	, ""
	, "Options:"
	] ++ optlines ++ cmdlines
  where
	-- To get consistent indentation of options, generate the
	-- usage for all options at once. A command's options will
	-- be displayed after the command.
	alloptlines = filter (not . null) $
		lines $ usageInfo "" $
			concatMap cmdoptions scmds ++ commonoptions
	(cmdlines, optlines) = go Nothing scmds alloptlines []
	go _ [] os ls = (ls, os)
	go section (c:cs) os ls = go section' cs os' ls'
	  where
		ls' = ls++sectionheader++(l:o)
		sectionheader
			| section == section' = []
			| otherwise = ["", descSection (cmdsection c) ++ ":", ""]
		section' = Just (cmdsection c)
		(o, os') = splitAt (length $ cmdoptions c) os
		l = concat
			[ cmdname c
			, namepad (cmdname c)
			, cmdparamdesc c
			, descpad (cmdparamdesc c)
			, cmddesc c
			]
	pad n s = replicate (n - length s) ' '
	namepad = pad $ longest cmdname + 1
	descpad = pad $ longest cmdparamdesc + 2
	longest f = foldl max 0 $ map (length . f) cmds
	scmds = sort cmds

{- Descriptions of params used in usage messages. -}
paramPaths :: String
paramPaths = paramOptional $ paramRepeating paramPath -- most often used
paramPath :: String
paramPath = "PATH"
paramKey :: String
paramKey = "KEY"
paramDesc :: String
paramDesc = "DESC"
paramUrl :: String
paramUrl = "URL"
paramNumber :: String
paramNumber = "NUMBER"
paramNumRange :: String
paramNumRange = "NUM|RANGE"
paramRemote :: String
paramRemote = "REMOTE"
paramGlob :: String
paramGlob = "GLOB"
paramName :: String
paramName = "NAME"
paramValue :: String
paramValue = "VALUE"
paramUUID :: String
paramUUID = "UUID"
paramType :: String
paramType = "TYPE"
paramDate :: String
paramDate = "DATE"
paramTime :: String
paramTime = "TIME"
paramFormat :: String
paramFormat = "FORMAT"
paramFile :: String
paramFile = "FILE"
paramGroup :: String
paramGroup = "GROUP"
paramSize :: String
paramSize = "SIZE"
paramKeyValue :: String
paramKeyValue = "K=V"
paramNothing :: String
paramNothing = ""
paramRepeating :: String -> String
paramRepeating s = s ++ " ..."
paramOptional :: String -> String
paramOptional s = "[" ++ s ++ "]"
paramPair :: String -> String -> String
paramPair a b = a ++ " " ++ b