    {-# LANGUAGE CPP, RecordWildCards, DeriveDataTypeable #-}
    {-|

    Options common to most hledger reports.

    -}

    module Hledger.Reports.ReportOptions (
      ReportOpts(..),
      BalanceType(..),
      AccountListMode(..),
      FormatStr,
      defreportopts,
      rawOptsToReportOpts,
      checkReportOpts,
      flat_,
      tree_,
      whichDateFromOpts,
      journalSelectingAmountFromOpts,
      queryFromOpts,
      queryFromOptsOnly,
      queryOptsFromOpts,
      transactionDateFn,
      postingDateFn,
      reportStartDate,
      reportEndDate,
      reportStartEndDates,

      tests_Hledger_Reports_ReportOptions
    )
    where

    import Data.Data (Data)
    #if !MIN_VERSION_base(4,8,0)
    import Data.Functor.Compat ((<$>))
    #endif
    import Data.Maybe
    import qualified Data.Text as T
    import Data.Typeable (Typeable)
    import Data.Time.Calendar
    import Data.Default
    import Safe
    import Test.HUnit
    import Text.Megaparsec.Error

    import Hledger.Data
    import Hledger.Query
    import Hledger.Utils

    type FormatStr = String

    -- | Which "balance" is being shown in a balance report.
    data BalanceType = PeriodChange      -- ^ The change of balance in each period.
                     | CumulativeChange  -- ^ The accumulated change across multiple periods.
                     | HistoricalBalance -- ^ The historical ending balance, including the effect of
                                         --   all postings before the report period. Unless altered by,
                                         --   a query, this is what you would see on a bank statement.
      deriving (Eq,Show,Data,Typeable)

    instance Default BalanceType where def = PeriodChange

    -- | Should accounts be displayed: in the command's default style, hierarchically, or as a flat list ?
    data AccountListMode = ALDefault | ALTree | ALFlat deriving (Eq, Show, Data, Typeable)

    instance Default AccountListMode where def = ALDefault

    -- | Standard options for customising report filtering and output,
    -- corresponding to hledger's command-line options and query language
    -- arguments. Used in hledger-lib and above.
    data ReportOpts = ReportOpts {
         period_         :: Period
        ,interval_       :: Interval
        ,clearedstatus_  :: Maybe ClearedStatus
        ,cost_           :: Bool
        ,depth_          :: Maybe Int
        ,display_        :: Maybe DisplayExp
        ,date2_          :: Bool
        ,empty_          :: Bool
        ,no_elide_       :: Bool
        ,real_           :: Bool
        ,format_         :: Maybe FormatStr
        ,query_          :: String -- all arguments, as a string
        -- register only
        ,average_        :: Bool
        ,related_        :: Bool
        -- balance only
        ,balancetype_    :: BalanceType
        ,accountlistmode_ :: AccountListMode
        ,drop_           :: Int
        ,row_total_      :: Bool
        ,no_total_       :: Bool
        ,value_          :: Bool
        ,pretty_tables_  :: Bool
     } deriving (Show, Data, Typeable)

    instance Default ReportOpts where def = defreportopts
    instance Default Bool where def = False

    defreportopts :: ReportOpts
    defreportopts = ReportOpts
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def
        def

    rawOptsToReportOpts :: RawOpts -> IO ReportOpts
    rawOptsToReportOpts rawopts = checkReportOpts <$> do
      d <- getCurrentDay
      let rawopts' = checkRawOpts rawopts
      return defreportopts{
         period_      = periodFromRawOpts d rawopts'
        ,interval_    = intervalFromRawOpts rawopts'
        ,clearedstatus_ = clearedStatusFromRawOpts rawopts'
        ,cost_        = boolopt "cost" rawopts'
        ,depth_       = maybeintopt "depth" rawopts'
        ,display_     = maybedisplayopt d rawopts'
        ,date2_       = boolopt "date2" rawopts'
        ,empty_       = boolopt "empty" rawopts'
        ,no_elide_    = boolopt "no-elide" rawopts'
        ,real_        = boolopt "real" rawopts'
        ,format_      = maybestringopt "format" rawopts' -- XXX move to CliOpts or move validation from Cli.CliOptions to here
        ,query_       = unwords $ listofstringopt "args" rawopts' -- doesn't handle an arg like "" right
        ,average_     = boolopt "average" rawopts'
        ,related_     = boolopt "related" rawopts'
        ,balancetype_ = balancetypeopt rawopts'
        ,accountlistmode_ = accountlistmodeopt rawopts'
        ,drop_        = intopt "drop" rawopts'
        ,row_total_   = boolopt "row-total" rawopts'
        ,no_total_    = boolopt "no-total" rawopts'
        ,value_       = boolopt "value" rawopts'
        ,pretty_tables_ = boolopt "pretty-tables" rawopts'
        }

    -- | Do extra validation of raw option values, raising an error if there's a problem.
    checkRawOpts :: RawOpts -> RawOpts
    checkRawOpts rawopts
    -- our standard behaviour is to accept conflicting options actually,
    -- using the last one - more forgiving for overriding command-line aliases
    --   | countopts ["change","cumulative","historical"] > 1
    --     = usageError "please specify at most one of --change, --cumulative, --historical"
    --   | countopts ["flat","tree"] > 1
    --     = usageError "please specify at most one of --flat, --tree"
    --   | countopts ["daily","weekly","monthly","quarterly","yearly"] > 1
    --     = usageError "please specify at most one of --daily, "
      | otherwise = rawopts
    --   where
    --     countopts = length . filter (`boolopt` rawopts)

    -- | Do extra validation of report options, raising an error if there's a problem.
    checkReportOpts :: ReportOpts -> ReportOpts
    checkReportOpts ropts@ReportOpts{..} =
      either usageError (const ropts) $ do
        case depth_ of
          Just d | d < 0 -> Left "--depth should have a positive number"
          _              -> Right ()

    accountlistmodeopt :: RawOpts -> AccountListMode
    accountlistmodeopt rawopts =
      case reverse $ filter (`elem` ["tree","flat"]) $ map fst rawopts of
        ("tree":_) -> ALTree
        ("flat":_) -> ALFlat
        _          -> ALDefault

    balancetypeopt :: RawOpts -> BalanceType
    balancetypeopt rawopts =
      case reverse $ filter (`elem` ["change","cumulative","historical"]) $ map fst rawopts of
        ("historical":_) -> HistoricalBalance
        ("cumulative":_) -> CumulativeChange
        _                -> PeriodChange

    -- Get the period specified by the intersection of -b/--begin, -e/--end and/or
    -- -p/--period options, using the given date to interpret relative date expressions.
    periodFromRawOpts :: Day -> RawOpts -> Period
    periodFromRawOpts d rawopts =
      case (mearliestb, mlateste) of
        (Nothing, Nothing) -> PeriodAll
        (Just b, Nothing)  -> PeriodFrom b
        (Nothing, Just e)  -> PeriodTo e
        (Just b, Just e)   -> simplifyPeriod $
                              PeriodBetween b e
      where
        mearliestb = case beginDatesFromRawOpts d rawopts of
                       [] -> Nothing
                       bs -> Just $ minimum bs
        mlateste   = case endDatesFromRawOpts d rawopts of
                       [] -> Nothing
                       es -> Just $ maximum es

    -- Get all begin dates specified by -b/--begin or -p/--period options, in order,
    -- using the given date to interpret relative date expressions.
    beginDatesFromRawOpts :: Day -> RawOpts -> [Day]
    beginDatesFromRawOpts d = catMaybes . map (begindatefromrawopt d)
      where
        begindatefromrawopt d (n,v)
          | n == "begin" =
              either (\e -> usageError $ "could not parse "++n++" date: "++parseErrorPretty e) Just $
              fixSmartDateStrEither' d (T.pack v)
          | n == "period" =
            case
              either (\e -> usageError $ "could not parse period option: "++parseErrorPretty e) id $
              parsePeriodExpr d (stripquotes $ T.pack v)
            of
              (_, DateSpan (Just b) _) -> Just b
              _                        -> Nothing
          | otherwise = Nothing

    -- Get all end dates specified by -e/--end or -p/--period options, in order,
    -- using the given date to interpret relative date expressions.
    endDatesFromRawOpts :: Day -> RawOpts -> [Day]
    endDatesFromRawOpts d = catMaybes . map (enddatefromrawopt d)
      where
        enddatefromrawopt d (n,v)
          | n == "end" =
              either (\e -> usageError $ "could not parse "++n++" date: "++parseErrorPretty e) Just $
              fixSmartDateStrEither' d (T.pack v)
          | n == "period" =
            case
              either (\e -> usageError $ "could not parse period option: "++parseErrorPretty e) id $
              parsePeriodExpr d (stripquotes $ T.pack v)
            of
              (_, DateSpan _ (Just e)) -> Just e
              _                        -> Nothing
          | otherwise = Nothing

    -- | Get the report interval, if any, specified by the last of -p/--period,
    -- -D/--daily, -W/--weekly, -M/--monthly etc. options.
    intervalFromRawOpts :: RawOpts -> Interval
    intervalFromRawOpts = lastDef NoInterval . catMaybes . map intervalfromrawopt
      where
        intervalfromrawopt (n,v)
          | n == "period" =
              either (\e -> usageError $ "could not parse period option: "++parseErrorPretty e) (Just . fst) $
              parsePeriodExpr nulldate (stripquotes $ T.pack v) -- reference date does not affect the interval
          | n == "daily"     = Just $ Days 1
          | n == "weekly"    = Just $ Weeks 1
          | n == "monthly"   = Just $ Months 1
          | n == "quarterly" = Just $ Quarters 1
          | n == "yearly"    = Just $ Years 1
          | otherwise = Nothing

    -- | Get the cleared status, if any, specified by the last of -C/--cleared,
    -- --pending, -U/--uncleared options.
    clearedStatusFromRawOpts :: RawOpts -> Maybe ClearedStatus
    clearedStatusFromRawOpts = lastMay . catMaybes . map clearedstatusfromrawopt
      where
        clearedstatusfromrawopt (n,_)
          | n == "cleared"   = Just Cleared
          | n == "pending"   = Just Pending
          | n == "uncleared" = Just Uncleared
          | otherwise        = Nothing

    type DisplayExp = String

    maybedisplayopt :: Day -> RawOpts -> Maybe DisplayExp
    maybedisplayopt d rawopts =
        maybe Nothing (Just . regexReplaceBy "\\[.+?\\]" fixbracketeddatestr) $ maybestringopt "display" rawopts
        where
          fixbracketeddatestr "" = ""
          fixbracketeddatestr s = "[" ++ fixSmartDateStr d (T.pack $ init $ tail s) ++ "]"

    -- | Select the Transaction date accessor based on --date2.
    transactionDateFn :: ReportOpts -> (Transaction -> Day)
    transactionDateFn ReportOpts{..} = if date2_ then transactionDate2 else tdate

    -- | Select the Posting date accessor based on --date2.
    postingDateFn :: ReportOpts -> (Posting -> Day)
    postingDateFn ReportOpts{..} = if date2_ then postingDate2 else postingDate

    -- | Report which date we will report on based on --date2.
    whichDateFromOpts :: ReportOpts -> WhichDate
    whichDateFromOpts ReportOpts{..} = if date2_ then SecondaryDate else PrimaryDate

    -- | Legacy-compatible convenience aliases for accountlistmode_.
    tree_ :: ReportOpts -> Bool
    tree_ = (==ALTree) . accountlistmode_

    flat_ :: ReportOpts -> Bool
    flat_ = (==ALFlat) . accountlistmode_

    -- depthFromOpts :: ReportOpts -> Int
    -- depthFromOpts opts = min (fromMaybe 99999 $ depth_ opts) (queryDepth $ queryFromOpts nulldate opts)

    -- | Convert this journal's postings' amounts to the cost basis amounts if
    -- specified by options.
    journalSelectingAmountFromOpts :: ReportOpts -> Journal -> Journal
    journalSelectingAmountFromOpts opts
        | cost_ opts = journalConvertAmountsToCost
        | otherwise = id

    -- | Convert report options and arguments to a query.
    queryFromOpts :: Day -> ReportOpts -> Query
    queryFromOpts d ReportOpts{..} = simplifyQuery $ And $ [flagsq, argsq]
      where
        flagsq = And $
                  [(if date2_ then Date2 else Date) $ periodAsDateSpan period_]
                  ++ (if real_ then [Real True] else [])
                  ++ (if empty_ then [Empty True] else []) -- ?
                  ++ (maybe [] ((:[]) . Status) clearedstatus_)
                  ++ (maybe [] ((:[]) . Depth) depth_)
        argsq = fst $ parseQuery d (T.pack query_)

    -- | Convert report options to a query, ignoring any non-flag command line arguments.
    queryFromOptsOnly :: Day -> ReportOpts -> Query
    queryFromOptsOnly _d ReportOpts{..} = simplifyQuery flagsq
      where
        flagsq = And $
                  [(if date2_ then Date2 else Date) $ periodAsDateSpan period_]
                  ++ (if real_ then [Real True] else [])
                  ++ (if empty_ then [Empty True] else []) -- ?
                  ++ (maybe [] ((:[]) . Status) clearedstatus_)
                  ++ (maybe [] ((:[]) . Depth) depth_)

    tests_queryFromOpts :: [Test]
    tests_queryFromOpts = [
     "queryFromOpts" ~: do
      assertEqual "" Any (queryFromOpts nulldate defreportopts)
      assertEqual "" (Acct "a") (queryFromOpts nulldate defreportopts{query_="a"})
      assertEqual "" (Desc "a a") (queryFromOpts nulldate defreportopts{query_="desc:'a a'"})
      assertEqual "" (Date $ mkdatespan "2012/01/01" "2013/01/01")
                     (queryFromOpts nulldate defreportopts{period_=PeriodFrom (parsedate "2012/01/01")
                                                          ,query_="date:'to 2013'"
                                                          })
      assertEqual "" (Date2 $ mkdatespan "2012/01/01" "2013/01/01")
                     (queryFromOpts nulldate defreportopts{query_="date2:'in 2012'"})
      assertEqual "" (Or [Acct "a a", Acct "'b"])
                     (queryFromOpts nulldate defreportopts{query_="'a a' 'b"})
     ]

    -- | Convert report options and arguments to query options.
    queryOptsFromOpts :: Day -> ReportOpts -> [QueryOpt]
    queryOptsFromOpts d ReportOpts{..} = flagsqopts ++ argsqopts
      where
        flagsqopts = []
        argsqopts = snd $ parseQuery d (T.pack query_)

    tests_queryOptsFromOpts :: [Test]
    tests_queryOptsFromOpts = [
     "queryOptsFromOpts" ~: do
      assertEqual "" [] (queryOptsFromOpts nulldate defreportopts)
      assertEqual "" [] (queryOptsFromOpts nulldate defreportopts{query_="a"})
      assertEqual "" [] (queryOptsFromOpts nulldate defreportopts{period_=PeriodFrom (parsedate "2012/01/01")
                                                                 ,query_="date:'to 2013'"
                                                                 })
     ]

    -- | The effective report start date is the one specified by options or queries,
    -- otherwise the earliest transaction or posting date in the journal,
    -- otherwise (for an empty journal) nothing.
    -- Needs IO to parse smart dates in options/queries.
    reportStartDate :: Journal -> ReportOpts -> IO (Maybe Day)
    reportStartDate j ropts = (fst <$>) <$> reportStartEndDates j ropts

    -- | The effective report end date is the one specified by options or queries,
    -- otherwise the latest transaction or posting date in the journal,
    -- otherwise (for an empty journal) nothing.
    -- Needs IO to parse smart dates in options/queries.
    reportEndDate :: Journal -> ReportOpts -> IO (Maybe Day)
    reportEndDate j ropts = (snd <$>) <$> reportStartEndDates j ropts

    reportStartEndDates :: Journal -> ReportOpts -> IO (Maybe (Day,Day))
    reportStartEndDates j ropts = do
      today <- getCurrentDay
      let
        q = queryFromOpts today ropts
        mrequestedstartdate = queryStartDate False q
        mrequestedenddate = queryEndDate False q
      return $
        case journalDateSpan False j of  -- don't bother with secondary dates
          DateSpan (Just journalstartdate) (Just journalenddate) ->
            Just (fromMaybe journalstartdate mrequestedstartdate, fromMaybe journalenddate mrequestedenddate)
          _ -> Nothing

    tests_Hledger_Reports_ReportOptions :: Test
    tests_Hledger_Reports_ReportOptions = TestList $
        tests_queryFromOpts
     ++ tests_queryOptsFromOpts