{-# OPTIONS_GHC -cpp #-}
{-|
Command-line options for the application.
-}

module Options 
where
import System.Console.GetOpt
import System.Environment
import Ledger.IO (IOArgs,myLedgerPath,myTimelogPath)
import Ledger.Utils
import Ledger.Types
import Ledger.Dates
import Codec.Binary.UTF8.String (decodeString)
import Control.Monad (liftM)

progname      = "hledger"
timeprogname  = "hours"

usagehdr = (
  "Usage: hledger [OPTIONS] [COMMAND [PATTERNS]]\n" ++
  "       hours   [OPTIONS] [COMMAND [PATTERNS]]\n" ++
  "       hledger convert CSVFILE ACCOUNTNAME RULESFILE\n" ++
  "\n" ++
  "hledger uses your ~/.ledger or $LEDGER file (or another specified with -f),\n" ++
  "while hours uses your ~/.timelog or $TIMELOG file.\n" ++
  "\n" ++
  "COMMAND is one of (may be abbreviated):\n" ++
  "  add       - prompt for new transactions and add them to the ledger\n" ++
  "  balance   - show accounts, with balances\n" ++
  "  convert   - convert CSV data to ledger format and print on stdout\n" ++
  "  histogram - show transaction counts per day or other interval\n" ++
  "  print     - show transactions in ledger format\n" ++
  "  register  - show transactions as a register with running balance\n" ++
  "  stats     - show various statistics for a ledger\n" ++
#ifdef VTY
  "  ui        - run a simple curses-based text ui\n" ++
#endif
#ifdef HAPPS
  "  web       - run a simple web ui\n" ++
#endif
  "  test      - run self-tests\n" ++
  "\n" ++
  "PATTERNS are regular expressions which filter by account name.\n" ++
  "Prefix with desc: to filter by transaction description instead.\n" ++
  "Prefix with not: to negate a pattern. When using both, not: comes last.\n" ++
  "\n" ++
  "DATES can be y/m/d or ledger-style smart dates like \"last month\".\n" ++
  "\n" ++
  "Options:"
  )
usageftr = ""
usage = usageInfo usagehdr options ++ usageftr

-- | Command-line options we accept.
options :: [OptDescr Opt]
options = [
  Option ['f'] ["file"]         (ReqArg File "FILE")   "use a different ledger/timelog file; - means stdin"
 ,Option ['b'] ["begin"]        (ReqArg Begin "DATE")  "report on transactions on or after this date"
 ,Option ['e'] ["end"]          (ReqArg End "DATE")    "report on transactions before this date"
 ,Option ['p'] ["period"]       (ReqArg Period "EXPR") ("report on transactions during the specified period\n" ++
                                                       "and/or with the specified reporting interval\n")
 ,Option ['C'] ["cleared"]      (NoArg  Cleared)       "report only on cleared transactions"
 ,Option ['U'] ["uncleared"]    (NoArg  UnCleared)     "report only on uncleared transactions"
 ,Option ['B'] ["cost","basis"] (NoArg  CostBasis)     "report cost of commodities"
 ,Option []    ["depth"]        (ReqArg Depth "N")     "hide accounts/transactions deeper than this"
 ,Option ['d'] ["display"]      (ReqArg Display "EXPR") ("show only transactions matching EXPR (where\n" ++
                                                        "EXPR is 'dOP[DATE]' and OP is <, <=, =, >=, >)")
 ,Option ['E'] ["empty"]        (NoArg  Empty)         "show empty/zero things which are normally elided"
 ,Option ['R'] ["real"]         (NoArg  Real)          "report only on real (non-virtual) transactions"
 ,Option []    ["no-total"]     (NoArg  NoTotal)       "balance report: hide the final total"
-- ,Option ['s'] ["subtotal"]     (NoArg  SubTotal)      "balance report: show subaccounts"
 ,Option ['W'] ["weekly"]       (NoArg  WeeklyOpt)     "register report: show weekly summary"
 ,Option ['M'] ["monthly"]      (NoArg  MonthlyOpt)    "register report: show monthly summary"
 ,Option ['Q'] ["quarterly"]    (NoArg  QuarterlyOpt)  "register report: show quarterly summary"
 ,Option ['Y'] ["yearly"]       (NoArg  YearlyOpt)     "register report: show yearly summary"
 ,Option ['h'] ["help"] (NoArg  Help)                  "show this help"
 ,Option ['V'] ["version"]      (NoArg  Version)       "show version information"
 ,Option ['v'] ["verbose"]      (NoArg  Verbose)       "show verbose test output"
 ,Option []    ["binary-filename"] (NoArg BinaryFilename) "show the download filename for this hledger build"
 ,Option []    ["debug"]        (NoArg  Debug)         "show some debug output"
 ,Option []    ["debug-no-ui"]  (NoArg  DebugNoUI)     "run ui commands with no output"
 ]

-- | An option value from a command-line flag.
data Opt = 
    File    {value::String} | 
    Begin   {value::String} | 
    End     {value::String} | 
    Period  {value::String} | 
    Cleared | 
    UnCleared | 
    CostBasis | 
    Depth   {value::String} | 
    Display {value::String} | 
    Empty | 
    Real | 
    NoTotal |
    SubTotal |
    WeeklyOpt |
    MonthlyOpt |
    QuarterlyOpt |
    YearlyOpt |
    Help |
    Verbose |
    Version
    | BinaryFilename
    | Debug
    | DebugNoUI
    deriving (Show,Eq)

-- these make me nervous
optsWithConstructor f opts = concatMap get opts
    where get o = if f v == o then [o] else [] where v = value o

optsWithConstructors fs opts = concatMap get opts
    where get o = if any (\f -> f == o) fs then [o] else []

optValuesForConstructor f opts = concatMap get opts
    where get o = if f v == o then [v] else [] where v = value o

optValuesForConstructors fs opts = concatMap get opts
    where get o = if any (\f -> f v == o) fs then [v] else [] where v = value o

-- | Parse the command-line arguments into options, command name, and
-- command arguments. Any dates in the options are converted to explicit
-- YYYY/MM/DD format based on the current time.
parseArguments :: IO ([Opt], String, [String])
parseArguments = do
  args <- liftM (map decodeString) getArgs
  let (os,as,es) = getOpt Permute options args
--  istimequery <- usingTimeProgramName
--  let os' = if istimequery then (Period "today"):os else os
  os'' <- fixOptDates os
  case (as,es) of
    (cmd:args,[])   -> return (os'',cmd,args)
    ([],[])         -> return (os'',"",[])
    (_,errs)        -> ioError (userError (concat errs ++ usage))

-- | Convert any fuzzy dates within these option values to explicit ones,
-- based on today's date.
fixOptDates :: [Opt] -> IO [Opt]
fixOptDates opts = do
  d <- getCurrentDay
  return $ map (fixopt d) opts
  where
    fixopt d (Begin s)   = Begin $ fixSmartDateStr d s
    fixopt d (End s)     = End $ fixSmartDateStr d s
    fixopt d (Display s) = -- hacky
        Display $ gsubRegexPRBy "\\[.+?\\]" fixbracketeddatestr s
        where fixbracketeddatestr s = "[" ++ (fixSmartDateStr d $ init $ tail s) ++ "]"
    fixopt _ o            = o

-- | Figure out the overall date span we should report on, based on any
-- begin/end/period options provided. If there is a period option, the
-- others are ignored.
dateSpanFromOpts :: Day -> [Opt] -> DateSpan
dateSpanFromOpts refdate opts
    | not $ null popts = snd $ parsePeriodExpr refdate $ last popts
    | otherwise = DateSpan lastb laste
    where
      popts = optValuesForConstructor Period opts
      bopts = optValuesForConstructor Begin opts
      eopts = optValuesForConstructor End opts
      lastb = listtomaybeday bopts
      laste = listtomaybeday eopts
      listtomaybeday vs = if null vs then Nothing else Just $ parse $ last vs
          where parse = parsedate . fixSmartDateStr refdate

-- | Figure out the reporting interval, if any, specified by the options.
-- If there is a period option, the others are ignored.
intervalFromOpts :: [Opt] -> Interval
intervalFromOpts opts =
    case (periodopts, intervalopts) of
      ((p:_), _)            -> fst $ parsePeriodExpr d p where d = parsedate "0001/01/01" -- unused
      (_, (WeeklyOpt:_))    -> Weekly
      (_, (MonthlyOpt:_))   -> Monthly
      (_, (QuarterlyOpt:_)) -> Quarterly
      (_, (YearlyOpt:_))    -> Yearly
      (_, _)                -> NoInterval
    where
      periodopts   = reverse $ optValuesForConstructor Period opts
      intervalopts = reverse $ filter (`elem` [WeeklyOpt,MonthlyOpt,QuarterlyOpt,YearlyOpt]) opts

-- | Get the value of the (last) depth option, if any, otherwise a large number.
depthFromOpts :: [Opt] -> Int
depthFromOpts opts = fromMaybe 9999 $ listtomaybeint $ optValuesForConstructor Depth opts
    where
      listtomaybeint [] = Nothing
      listtomaybeint vs = Just $ read $ last vs

-- | Get the value of the (last) display option, if any.
displayFromOpts :: [Opt] -> Maybe String
displayFromOpts opts = listtomaybe $ optValuesForConstructor Display opts
    where
      listtomaybe [] = Nothing
      listtomaybe vs = Just $ last vs

-- | Get a maybe boolean representing the last cleared/uncleared option if any.
clearedValueFromOpts opts | null os = Nothing
                          | last os == Cleared = Just True
                          | otherwise = Just False
    where os = optsWithConstructors [Cleared,UnCleared] opts

-- | Was the program invoked via the \"hours\" alias ?
usingTimeProgramName :: IO Bool
usingTimeProgramName = do
  progname <- getProgName
  return $ map toLower progname == timeprogname

-- | Get the ledger file path from options, an environment variable, or a default
ledgerFilePathFromOpts :: [Opt] -> IO String
ledgerFilePathFromOpts opts = do
  istimequery <- usingTimeProgramName
  f <- if istimequery then myTimelogPath else myLedgerPath
  return $ last $ f:(optValuesForConstructor File opts)

-- | Gather filter pattern arguments into a list of account patterns and a
-- list of description patterns. We interpret pattern arguments as
-- follows: those prefixed with "desc:" are description patterns, all
-- others are account patterns; also patterns prefixed with "not:" are
-- negated. not: should come after desc: if both are used.
parsePatternArgs :: [String] -> ([String],[String])
parsePatternArgs args = (as, ds')
    where
      descprefix = "desc:"
      (ds, as) = partition (descprefix `isPrefixOf`) args
      ds' = map (drop (length descprefix)) ds

-- | Convert application options to more generic types for the library.
optsToIOArgs :: [Opt] -> [String] -> LocalTime -> IOArgs
optsToIOArgs opts args t = (dateSpanFromOpts (localDay t) opts
                         ,clearedValueFromOpts opts
                         ,Real `elem` opts
                         ,CostBasis `elem` opts
                         ,apats
                         ,dpats
                         ) where (apats,dpats) = parsePatternArgs args