-- Represents an item in the game.

module Internals
( Action(..)
, Object(..)
) where

----------------------------- Constants ------------------------------

data Object = 
    Item { -- All fields are required
        -- Easy way to identify items
        id          :: String,
        -- Horizontal coördinate in the level
        x           :: Int,
        -- Vertical coördinate in the level
        y           :: Int,
        name        :: String,
        -- Short description of the object
        description :: String,
        -- Counts how often the object can be used by the player. Either 
        -- infinite or a natural number
        useTimes    :: Maybe Int,
        -- List of conditional actions when the player is standing on this object
        actions     :: [Action],
        -- Interpretation depends on action with this object.
        value       :: Maybe Int
    }
    | Entity {
    -- Required fields
        -- Easy way to identify items
        id          :: String,
        -- Horizontal coördinate in the level
        x           :: Int,
        -- Vertical coördinate in the level
        y           :: Int,
        name        :: String,
        -- Short description of the object
        description :: String,
        -- List of conditional actions when the player is standing on this object
        actions     :: [Action],
    -- Optional fields
        -- The direction of the item. e.g. a door has a direction.
        direction   :: Maybe Direction,
        -- Some entities have health points.
        hp          :: Maybe Int,
        -- Interpretation depends on action with this object.
        value       :: Maybe Int
    }

data Direction = North 
               | East 
               | South 
               | West
               deriving (Show)

type Action = ([Condition], Event)

type Condition = Bool

type Event = *