{-# LANGUAGE NamedFieldPuns    #-}
{-# LANGUAGE OverloadedStrings #-}

-- | Contains checks for custom properties of the map json
module Properties (checkProperty) where


import           Control.Monad (unless)
import           Data.Text     (Text)
import           Tiled2        (Layer (layerProperties), Property, propertyName,
                                propertyValue)
import           Util          (prettyprint)

import           LintWriter    (LintWriter, complain, forbid, info, require,
                                suggest, warn)

-- | the point of this module
--
-- given a property, check if it is valid. It gets a reference
-- to its own layer since sometimes the presense of one property
-- implies the presence or absense of another.
--
-- The tests in here are meant to comply with the informal spec
-- at https://workadventu.re/map-building
--
-- I've attempted to build the LintWriter monad in a way
-- that should make this readable even to non-Haskellers
-- TODO: also pass the value of this property directly
checkProperty :: Layer -> Property -> LintWriter ()
checkProperty layer prop = case propName of
    "jitsiRoom" -> do
      info $ "found jitsi room: " <> prettyprint (propertyValue prop)
      suggestPropertyValue "jitsiTrigger" "onaction"
    "jitsiTrigger" ->
      requireProperty "jitsiRoom"
    "jitsiUrl" -> isForbidden
    "jitsiConfig" -> isForbidden
    "jitsiClientConfig" -> isForbidden
    "jitsiRoomAdminTag" -> isForbidden
    "playAudio" -> do
      -- TODO: check for url validity?
      pure ()
    "audioLoop" ->
      requireProperty "playAudio"
    "audioVolume" ->
      requireProperty "playAudio"
    "openWebsite" -> do
      suggestPropertyValue "openWebsiteTrigger" "onaction"
      require $ propertyValue prop
    "openWebsiteTrigger" ->
      requireProperty "openWebsite"
    "openWebsitePolicy" ->
      requireProperty "openWebsite"
    "exitUrl" -> pure ()
    "startLayer" -> pure ()
      -- could also make this a "hard error" (i.e. Left), but then it
      -- stops checking other properties as checkLayer short-circuits.
    _ -> warn $ "unknown property type " <> prettyprint propName
    where
      propName = propertyName prop
      -- | require some property in this layer
      requireProperty name = unless (hasProperty name layer)
        $ complain $ "property "<>prettyprint name<>" requires property "<>prettyprint propName
      -- | This property is forbidden and should not be used
      isForbidden = forbid $ "property " <> prettyprint propName <> " should not be used"
      -- TODO: check if the property has the correct value
      suggestPropertyValue :: Text -> Text -> LintWriter ()
      suggestPropertyValue name value = unless (hasProperty name layer)
        $ suggest $ "set property " <> prettyprint name <> " to " <> prettyprint value




-- | does this layer have the given property?
hasProperty :: Text -> Layer -> Bool
hasProperty name = any
  (\prop -> propertyName prop == name)
  . layerProperties