{-|

A 'TimeLog' is a parsed timelog file (generated by timeclock.el),
containing zero or more 'TimeLogEntry's. It can be converted to a
'RawLedger' for querying.

-}

module Ledger.TimeLog
where

import Ledger.Utils
import Ledger.Types
import Ledger.Currency
import Ledger.Amount
import Ledger.RawTransaction
import Ledger.Entry
import Ledger.RawLedger

instance Show TimeLogEntry where 
    show t = printf "%s %s %s" (show $ tlcode t) (tldatetime t) (tlcomment t)

instance Show TimeLog where
    show tl = printf "TimeLog with %d entries" $ length $ timelog_entries tl

-- | Convert a time log to a ledger.
ledgerFromTimeLog :: TimeLog -> RawLedger
ledgerFromTimeLog tl = 
    RawLedger [] [] (entriesFromTimeLogEntries $ timelog_entries tl) ""

-- | Convert time log entries to ledger entries.
entriesFromTimeLogEntries :: [TimeLogEntry] -> [Entry]

-- | When there is a trailing clockin entry, provide the missing clockout.
-- "Now" would be ideal but requires IO, for now we make it the same as
-- clockin time.
entriesFromTimeLogEntries [clockin@(TimeLogEntry _ t _)] = 
    entriesFromTimeLogEntries [clockin, (TimeLogEntry 'o' t "")]

entriesFromTimeLogEntries [clockin,clockout] =
    [
     Entry {
       edate         = indate,
       estatus       = True,
       ecode         = "",
       edescription  = accountname,
       ecomment      = "",
       etransactions = [
        RawTransaction accountname amount "",
        RawTransaction "assets:TIME" (-amount) ""
       ],
       epreceding_comment_lines=""}
    ]
    where
      accountname = tlcomment clockin
      indate      = showDateFrom intime
      intime      = parsedatetime $ tldatetime clockin
      outtime     = parsedatetime $ tldatetime clockout
      hours       = fromRational (toRational (diffUTCTime outtime intime) / 3600) -- whatever
      amount      = Amount (getcurrency "h") hours 1

entriesFromTimeLogEntries many =
    (entriesFromTimeLogEntries $ take 2 many) ++
    (entriesFromTimeLogEntries $ drop 2 many)

showDateFrom :: UTCTime -> String
showDateFrom = formatTime defaultTimeLocale "%Y/%m/%d"