-- Direct messages table
CREATE TABLE public.direct_messages (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  sender_id UUID NOT NULL,
  recipient_id UUID NOT NULL,
  message TEXT NOT NULL,
  read_at TIMESTAMPTZ,
  created_at TIMESTAMPTZ NOT NULL DEFAULT now()
);

-- Index for conversation lookups
CREATE INDEX idx_dm_sender ON public.direct_messages(sender_id, created_at DESC);
CREATE INDEX idx_dm_recipient ON public.direct_messages(recipient_id, created_at DESC);
CREATE INDEX idx_dm_conversation ON public.direct_messages(
  LEAST(sender_id, recipient_id),
  GREATEST(sender_id, recipient_id),
  created_at DESC
);

-- Enable RLS
ALTER TABLE public.direct_messages ENABLE ROW LEVEL SECURITY;

-- Users can read messages they sent or received
CREATE POLICY "Users can read own messages"
  ON public.direct_messages FOR SELECT
  TO authenticated
  USING (auth.uid() = sender_id OR auth.uid() = recipient_id);

-- Users can insert messages where they are the sender
CREATE POLICY "Users can send messages"
  ON public.direct_messages FOR INSERT
  TO authenticated
  WITH CHECK (auth.uid() = sender_id);

-- Users can update messages they received (for marking read)
CREATE POLICY "Recipients can mark messages read"
  ON public.direct_messages FOR UPDATE
  TO authenticated
  USING (auth.uid() = recipient_id)
  WITH CHECK (auth.uid() = recipient_id);

-- Enable realtime
ALTER PUBLICATION supabase_realtime ADD TABLE public.direct_messages;