{-# Language UndecidableInstances #-}
{-# Language AllowAmbiguousTypes #-}
module HBS2.Peer.Proto.Mailbox
  ( module HBS2.Peer.Proto.Mailbox
  , module HBS2.Peer.Proto.Mailbox.Message
  ) where

import HBS2.Prelude.Plated

import HBS2.Data.Types.SignedBox

import HBS2.Peer.Proto.Mailbox.Types
import HBS2.Peer.Proto.Mailbox.Message

import Codec.Serialise

data MailBoxStatusPayload s =
  MailBoxStatusPayload
  { mbsMailboxKey   :: MailboxKey s
  , mbsMailboxHash  :: HashRef
  }
  deriving stock (Generic)

data SetPolicyPayload s =
  SetPolicyPayload
  { sppMailboxKey    :: MailboxKey s
  , sppPolicyVersion :: PolicyVersion
  , sppPolicyRef     :: HashRef
  }
  deriving stock (Generic)

data GetPolicyPayload s =
  GetPolicyPayload
  { gppMailboxKey    :: MailboxKey s
  , gppPolicyVersion :: PolicyVersion
  , gppPolicyRef     :: HashRef
  }
  deriving stock (Generic)

data DeleteMessagesPayload s =
  DeleteMessagesPayload
  { dmpMailboxKey    :: MailboxKey s
  , dmpPredicate     :: MailboxMessagePredicate
  }
  deriving stock (Generic)

data MailBoxProtoMessage s e =
    SendMessage     (Message s) -- already has signed box
  | CheckMailbox    (SignedBox (MailboxKey s) s)
  | MailboxStatus   (SignedBox (MailBoxStatusPayload s) s)
  | SetPolicy       (SignedBox (SetPolicyPayload s) s)
  | GetPolicy       (SignedBox (GetPolicyPayload s) s)
  | CurrentPolicy   (GetPolicyPayload s)
  | DeleteMessages  (SignedBox (DeleteMessagesPayload s) s)
  deriving stock (Generic)

data MailBoxProto s e =
  MailBoxProtoV1 { mailBoxProtoPayload :: MailBoxProtoMessage s e }
  deriving stock (Generic)

instance ForMailbox s => Serialise (MailBoxStatusPayload s)
instance ForMailbox s => Serialise (SetPolicyPayload s)
instance ForMailbox s => Serialise (GetPolicyPayload s)
instance ForMailbox s => Serialise (DeleteMessagesPayload s)
instance ForMailbox s => Serialise (MailBoxProtoMessage s e)
instance ForMailbox s => Serialise (MailBoxProto s e)

class IsMailboxProtoAdapter e a where

mailboxProto :: forall e m p a . ( MonadIO m
                                 , Response e p m
                                 , HasDeferred p e m
                                 , IsMailboxProtoAdapter e a
                                 , p ~ MailBoxProto (Encryption e) e
                                 )
             => a
             -> MailBoxProto (Encryption e) e
             ->  m ()

mailboxProto adapter mess = do
  -- common stuff

  case mailBoxProtoPayload mess of
    SendMessage{} -> do
      -- TODO: implement-SendMessage
      --   [ ] check-if-mailbox-exists
      --   [ ] check-message-signature
      --   [ ] if-already-processed-then-skip
      --   [ ] store-message-hash-block-with-ttl
      --   [ ] if-message-to-this-mailbox-then store-message
      --   [ ] gossip-message
      none

    CheckMailbox{} -> do
      -- TODO: implement-CheckMailbox
      --  [ ]  check-signed-box-or-drop
      --  [ ]  if-client-has-mailbox-then
      --  [ ]     get-mailbox-status
      --  [ ]     answer-MailboxStatus
      --  [ ]  gossip-message?
      none

    MailboxStatus{} -> do
      -- TODO: implement-MailboxStatus
      --
      --  [ ]  if-do-gossip-setting-then
      --  [ ]     gossip-MailboxStatus
      --
      --  [ ]  check-signed-box-or-drop
      --  [ ]  if-client-has-mailbox-then
      --  [ ]     get-mailbox-status
      --  [ ]     answer-MailboxStatus
      --
      none

    SetPolicy{} -> do
      none

    GetPolicy{} -> do
      none

    CurrentPolicy{} -> do
      none

    DeleteMessages{} -> do
      none