Classification.hs

{- |
Module      : ExchangeAlgebra.Accounting.Account.Classification
Description : Account metadata types shared by Base and the account registry.
-}
module ExchangeAlgebra.Accounting.Account.Classification
    ( AccountDivision(..)
    , Side(..)
    , ClosingRule(..)
    , FixedCurrent(..)
    , AccountRole(..)
    , PostingCapability(..)
    , DivisionSemantics(..)
    , HomeSideSemantics(..)
    , ReportingEligibility(..)
    ) where

import Control.DeepSeq (NFData(..))

-- | Account division (financial-statement classification). The
-- 'ExchangeAlgebra.Accounting.Exchange.AccountBase' correspondence instance
-- lives in "ExchangeAlgebra.Accounting.Exchange" (the class's home module).
data AccountDivision = Assets       -- ^ Assets
                     | Equity       -- ^ Equity
                     | Liability    -- ^ Liability
                     | Cost         -- ^ Cost
                     | Revenue      -- ^ Revenue
                     deriving (Ord, Show, Eq)

instance NFData AccountDivision where
    rnf value = value `seq` ()

-- | Credit/debit distinction. v'Side' is the wildcard used by legacy APIs.
data Side = Credit -- ^ Credit side.
          | Debit  -- ^ Debit side.
          | Side   -- ^ Wildcard.
          deriving (Ord, Show, Eq)

instance NFData Side where
    rnf value = value `seq` ()

-- | Registry-level policy for automatic closing entries.
--
-- 'CloseByDivision' derives the transfer side from 'AccountDivision'.
-- 'NoClose' is an explicit override. Future policies may add explicit
-- keep/flip constructors without returning to an account-title case split.
data ClosingRule = CloseByDivision -- ^ Close Cost/Revenue accounts according to their division.
                 | NoClose         -- ^ Do not generate an automatic closing entry.
                 deriving (Show, Eq)

instance NFData ClosingRule where
    rnf value = value `seq` ()

-- | Fixed/Current distinction. Used for classifying account titles as fixed or current.
data FixedCurrent = Fixed   -- ^ Fixed
                  | Current -- ^ Current
                  | Other   -- ^ Other (expenses, revenues, etc.)
                  deriving (Show, Eq)

instance NFData FixedCurrent where
    rnf value = value `seq` ()

-- | Accounting role of an account-basis coordinate. Roles are not assumed to
-- be mutually exclusive; see
-- 'ExchangeAlgebra.Accounting.Account.Registry.AccountSemantics' in the
-- account registry.
data AccountRole
    = OrdinaryAccount
    | ContraAccount
    | ReciprocalAccount
    | SuspenseOrClearingAccount
    | ClosingDevice
    | AttributionAccount
    | PeriodResult
    | ReportingSubtotal
    deriving (Show, Eq)

instance NFData AccountRole where
    rnf value = value `seq` ()

-- | Context in which an account title may be used as a posting coordinate.
-- Enforcement is introduced by the checked-conversion API in a later land;
-- this type is the canonical metadata used by that gate.
data PostingCapability
    = OrdinaryPosting
    | ClosingOnly
    | ConsolidationOnly
    | EngineGeneratedOnly
    | NotPostable
    deriving (Show, Eq)

instance NFData PostingCapability where
    rnf value = value `seq` ()

-- | Meaning of the legacy five-way 'AccountDivision' value.
--
-- This separates a genuine statement classification from a bookkeeping
-- control class or an internal direction encoding. The wrapped legacy value
-- remains available for 0.4.x-compatible algebraic behavior.
data DivisionSemantics
    = StatementDivision AccountDivision
    | BookkeepingControlClass AccountDivision
    | DirectionEncoding AccountDivision
    | NoStatementDivision
    deriving (Show, Eq)

instance NFData DivisionSemantics where
    rnf value = case value of
        StatementDivision division        -> rnf division
        BookkeepingControlClass division  -> rnf division
        DirectionEncoding division        -> rnf division
        NoStatementDivision               -> ()

-- | Semantic status of an account's normal posting side.
data HomeSideSemantics
    = FixedHomeSide Side
    | ContextDependentHomeSide
    | NoFixedHomeSide
    | NoPostingSide
    deriving (Show, Eq)

instance NFData HomeSideSemantics where
    rnf value = case value of
        FixedHomeSide side       -> rnf side
        ContextDependentHomeSide -> ()
        NoFixedHomeSide          -> ()
        NoPostingSide            -> ()

-- | Coarse reporting eligibility. Actual presentation remains a function of
-- reporting context and policy and is implemented in a later land.
data ReportingEligibility
    = StatementEligible
    | ContextualPresentation
    | DerivedPresentation
    | NotPresented
    deriving (Show, Eq)

instance NFData ReportingEligibility where
    rnf value = value `seq` ()