{-# LANGUAGE ScopedTypeVariables       #-}
{-# LANGUAGE OverloadedStrings         #-}
{-# LANGUAGE ForeignFunctionInterface  #-}
{-# LANGUAGE LambdaCase                #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  Miso.Effect.Storage
-- Copyright   :  (C) 2016-2018 David M. Johnson
-- License     :  BSD3-style (see the file LICENSE)
-- Maintainer  :  David M. Johnson <djohnson.m@gmail.com>
-- Stability   :  experimental
-- Portability :  non-portable
--
-- This module provides an interface to the
-- [Web Storage API](https://developer.mozilla.org/en-US/docs/Web/API/Web_Storage_API).
----------------------------------------------------------------------------
module Miso.Effect.Storage
  ( -- * Retrieve storage
    getLocalStorage
  , getSessionStorage
    -- * Set items in storage
  , setLocalStorage
  , setSessionStorage
    -- * Remove items from storage
  , removeLocalStorage
  , removeSessionStorage
    -- * Clear storage
  , clearLocalStorage
  , clearSessionStorage
    -- * Get number of items in storage
  , localStorageLength
  , sessionStorageLength
  ) where

import           Data.Aeson hiding (Object, String)
import           GHCJS.Marshal
import           GHCJS.Types

import           Miso.FFI
import qualified Miso.FFI.Storage as Storage
import           Miso.String

-- | Helper for retrieving either local or session storage
getStorageCommon
  :: FromJSON b => (t -> JSM (Maybe JSVal)) -> t -> JSM (Either String b)
getStorageCommon :: (t -> JSM (Maybe JSVal)) -> t -> JSM (Either String b)
getStorageCommon t -> JSM (Maybe JSVal)
f t
key = do
  Maybe JSVal
result :: Maybe JSVal <- t -> JSM (Maybe JSVal)
f t
key
  case Maybe JSVal
result of
    Maybe JSVal
Nothing -> Either String b -> JSM (Either String b)
forall (f :: * -> *) a. Applicative f => a -> f a
pure (Either String b -> JSM (Either String b))
-> Either String b -> JSM (Either String b)
forall a b. (a -> b) -> a -> b
$ String -> Either String b
forall a b. a -> Either a b
Left String
"Not Found"
    Just JSVal
v -> do
      Value
r <- JSVal -> JSM Value
forall json. FromJSON json => JSVal -> JSM json
parse JSVal
v
      Either String b -> JSM (Either String b)
forall (f :: * -> *) a. Applicative f => a -> f a
pure (Either String b -> JSM (Either String b))
-> Either String b -> JSM (Either String b)
forall a b. (a -> b) -> a -> b
$ case Value -> Result b
forall a. FromJSON a => Value -> Result a
fromJSON Value
r of
        Success b
x -> b -> Either String b
forall a b. b -> Either a b
Right b
x
        Error String
y -> String -> Either String b
forall a b. a -> Either a b
Left String
y

-- | Retrieve a value stored under given key in session storage
getSessionStorage :: FromJSON model => MisoString -> JSM (Either String model)
getSessionStorage :: MisoString -> JSM (Either String model)
getSessionStorage =
  (MisoString -> JSM (Maybe JSVal))
-> MisoString -> JSM (Either String model)
forall b t.
FromJSON b =>
(t -> JSM (Maybe JSVal)) -> t -> JSM (Either String b)
getStorageCommon ((MisoString -> JSM (Maybe JSVal))
 -> MisoString -> JSM (Either String model))
-> (MisoString -> JSM (Maybe JSVal))
-> MisoString
-> JSM (Either String model)
forall a b. (a -> b) -> a -> b
$ \MisoString
t -> do
    Storage
s <- JSM Storage
Storage.sessionStorage
    JSVal
r <- Storage -> MisoString -> JSM JSVal
Storage.getItem Storage
s MisoString
t
    JSVal -> JSM (Maybe JSVal)
forall a. FromJSVal a => JSVal -> JSM (Maybe a)
fromJSVal JSVal
r

-- | Retrieve a value stored under given key in local storage
getLocalStorage :: FromJSON model => MisoString -> JSM (Either String model)
getLocalStorage :: MisoString -> JSM (Either String model)
getLocalStorage = (MisoString -> JSM (Maybe JSVal))
-> MisoString -> JSM (Either String model)
forall b t.
FromJSON b =>
(t -> JSM (Maybe JSVal)) -> t -> JSM (Either String b)
getStorageCommon ((MisoString -> JSM (Maybe JSVal))
 -> MisoString -> JSM (Either String model))
-> (MisoString -> JSM (Maybe JSVal))
-> MisoString
-> JSM (Either String model)
forall a b. (a -> b) -> a -> b
$ \MisoString
t -> do
    Storage
s <- JSM Storage
Storage.localStorage
    JSVal
r <- Storage -> MisoString -> JSM JSVal
Storage.getItem Storage
s MisoString
t
    JSVal -> JSM (Maybe JSVal)
forall a. FromJSVal a => JSVal -> JSM (Maybe a)
fromJSVal JSVal
r

-- | Set the value of a key in local storage.
--
-- @setLocalStorage key value@ sets the value of @key@ to @value@.
setLocalStorage :: ToJSON model => MisoString -> model -> JSM ()
setLocalStorage :: MisoString -> model -> JSM ()
setLocalStorage MisoString
key model
model = do
  Storage
s <- JSM Storage
Storage.localStorage
  Storage -> MisoString -> MisoString -> JSM ()
Storage.setItem Storage
s MisoString
key (MisoString -> JSM ()) -> JSM MisoString -> JSM ()
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< model -> JSM MisoString
forall json. ToJSON json => json -> JSM MisoString
stringify model
model

-- | Set the value of a key in session storage.
--
-- @setSessionStorage key value@ sets the value of @key@ to @value@.
setSessionStorage :: ToJSON model => MisoString -> model -> JSM ()
setSessionStorage :: MisoString -> model -> JSM ()
setSessionStorage MisoString
key model
model = do
  Storage
s <- JSM Storage
Storage.sessionStorage
  Storage -> MisoString -> MisoString -> JSM ()
Storage.setItem Storage
s MisoString
key (MisoString -> JSM ()) -> JSM MisoString -> JSM ()
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< model -> JSM MisoString
forall json. ToJSON json => json -> JSM MisoString
stringify model
model

-- | Removes an item from local storage
--
-- @removeLocalStorage key@ removes the value of @key@.
removeLocalStorage :: MisoString -> JSM ()
removeLocalStorage :: MisoString -> JSM ()
removeLocalStorage MisoString
key = do
  Storage
s <- JSM Storage
Storage.localStorage
  Storage -> MisoString -> JSM ()
Storage.removeItem Storage
s MisoString
key

-- | Removes an item from session storage.
--
-- @removeSessionStorage key@ removes the value of @key@.
removeSessionStorage :: MisoString -> JSM ()
removeSessionStorage :: MisoString -> JSM ()
removeSessionStorage MisoString
key = do
  Storage
s <- JSM Storage
Storage.sessionStorage
  Storage -> MisoString -> JSM ()
Storage.removeItem Storage
s MisoString
key

-- | Clear local storage
--
-- @clearLocalStorage@ removes all values from local storage.
clearLocalStorage :: JSM ()
clearLocalStorage :: JSM ()
clearLocalStorage = Storage -> JSM ()
Storage.clear (Storage -> JSM ()) -> JSM Storage -> JSM ()
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< JSM Storage
Storage.localStorage

-- | Clear session storage
--
-- @clearSessionStorage@ removes all values from session storage.
clearSessionStorage :: JSM ()
clearSessionStorage :: JSM ()
clearSessionStorage = Storage -> JSM ()
Storage.clear (Storage -> JSM ()) -> JSM Storage -> JSM ()
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< JSM Storage
Storage.sessionStorage

-- | Local storage length
--
-- @localStorageLength@ returns the count of items in local storage
localStorageLength :: JSM Int
localStorageLength :: JSM Int
localStorageLength = Storage -> JSM Int
Storage.length (Storage -> JSM Int) -> JSM Storage -> JSM Int
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< JSM Storage
Storage.localStorage

-- | Session storage length
--
-- @sessionStorageLength@ returns the count of items in session storage
sessionStorageLength :: JSM Int
sessionStorageLength :: JSM Int
sessionStorageLength = Storage -> JSM Int
Storage.length (Storage -> JSM Int) -> JSM Storage -> JSM Int
forall (m :: * -> *) a b. Monad m => (a -> m b) -> m a -> m b
=<< JSM Storage
Storage.sessionStorage