content: -- Copyright (c) 2016-present, Facebook, Inc.
  -- All rights reserved.
  --
  -- This source code is licensed under the BSD-style license found in the
  -- LICENSE file in the root directory of this source tree.
  
  {-# LANGUAGE GADTs #-}
  {-# LANGUAGE LambdaCase #-}
  {-# LANGUAGE OverloadedStrings #-}
  
  module Duckling.AmountOfMoney.EN.NZ.Rules
    ( rules
    ) where
  
  import Data.HashMap.Strict (HashMap)
  import Data.String
  import Data.Text (Text)
  import Prelude
  
  import Duckling.AmountOfMoney.Helpers
  import Duckling.AmountOfMoney.Types (Currency(..))
  import Duckling.Numeral.Helpers (isPositive)
  import Duckling.Regex.Types
  import Duckling.Types
  
  import qualified Data.HashMap.Strict as HashMap
  import qualified Data.Text as Text
  import qualified Duckling.AmountOfMoney.Helpers as Helpers
  import qualified Duckling.Numeral.Types as TNumeral
  
  ruleAGrand :: Rule
  ruleAGrand = Rule
    { name = "a grand"
    , pattern =
      [ regex "a grand"
      ]
    , prod = \_ -> Just . Token AmountOfMoney . withValue 1000
                   $ currencyOnly NZD
    }
  
  ruleGrand :: Rule
  ruleGrand = Rule
    { name = "<amount> grand"
    , pattern =
      [ Predicate isPositive
      , regex "grand"
      ]
    , prod = \case
        (Token Numeral TNumeral.NumeralData{TNumeral.value = v}:_)
          -> Just . Token AmountOfMoney . withValue (1000 * v)
             $ currencyOnly NZD
        _ -> Nothing
    }
  
  ruleDollarCoin :: Rule
  ruleDollarCoin = Rule
    { name = "dollar coin"
    , pattern =
      [ regex "(nickel|dime|quarter)s?"
      ]
    , prod = \tokens -> case tokens of
        (Token RegexMatch (GroupMatch (match:_)):_) -> do
          c <- HashMap.lookup (Text.toLower match) Helpers.dollarCoins
          Just . Token AmountOfMoney . withValue c $ currencyOnly NZD
        _ -> Nothing
    }
  
  rules :: [Rule]
  rules =
    [ ruleAGrand
    , ruleGrand
    , ruleDollarCoin
    ]
  