module LoxTypes where

import Prelude hiding (False, True)

data CharToken
  = LeftParen
  | RightParen
  | LeftBrace
  | RightBrace
  | Comma
  | Dot
  | Minus
  | Plus
  | Semicolon
  | Slash
  | Star
  deriving (Eq)

instance Show CharToken where
  show LeftParen = "("
  show RightParen = ")"
  show LeftBrace = "{"
  show RightBrace = "}"
  show Comma = ","
  show Dot = "."
  show Minus = "-"
  show Plus = "+"
  show Semicolon = ";"
  show Slash = "/"
  show Star = "*"

data MultiCharToken
  = Bang
  | BangEqual
  | Equal
  | EqualEqual
  | Greater
  | GreaterEqual
  | Less
  | LessEqual
  deriving (Eq)

instance Show MultiCharToken where
  show Bang = "!"
  show BangEqual = "!="
  show Equal = "="
  show EqualEqual = "=="
  show Greater = ">"
  show GreaterEqual = ">="
  show Less = "<"
  show LessEqual = "<="

data Keywords
  = And
  | Class
  | Else
  | False
  | Func
  | For
  | If
  | Nil
  | Or
  | Print
  | Return
  | Super
  | This
  | True
  | Var
  | While
  deriving (Eq)

instance Show Keywords where
  show And = "and"
  show Class = "class"
  show Else = "else"
  show False = "false"
  show Func = "fun"
  show For = "for"
  show If = "if"
  show Nil = "nil"
  show Or = "or"
  show Print = "print"
  show Return = "return"
  show Super = "super"
  show This = "this"
  show True = "true"
  show Var = "var"
  show While = "while"

data Literal
  = Identifier Keywords
  | Str String
  | Number Double
  deriving (Eq, Show)

data LoxToken
  = Char CharToken
  | Op MultiCharToken
  | Lit Literal
  | Eof
  deriving (Eq, Show)

-- This is how Class Token is defined in Crafting Interpreters but we will
-- make use of the State in Megaparsec to report errors.
-- data LoxToken = Token
--   { tokenType :: TokenType,
--     lexeme :: Text,
--     literal :: Literal,
--     line :: Int
--   }
--   deriving (Eq)
--
-- instance Show LoxToken where
--   show (Token tokenType lexeme literal _) = show tokenType ++ " " ++ show lexeme ++ " " ++ show literal