import type { SessionEntry, ChatMessage } from 'plugins/Chat/client';
import type { SlashCommandResult } from './useSlashCommands';
import { useAuth } from 'hooks/useAuth';
import { useClient } from 'hooks/useClient';
import { useQuery, useQueryClient } from '@tanstack/react-query';

export const useSessions = () => {
  type RawSessionEntry = Omit<SessionEntry, 'provider'>;
  const client = useClient();
  const queryClient = useQueryClient();
  const { isAuthenticated } = useAuth();

  const { data: sessions = [] } = useQuery<RawSessionEntry[], Error, SessionEntry[]>({
    queryKey: ['SESSIONS'],
    enabled: isAuthenticated,
    queryFn: () => client.get<RawSessionEntry[]>('/sessions'),
    select: (data) => data.map((s) => ({ ...s, provider: 'claude' as const })),
  });

  const getMessages = (sessionId: string) => client.get<ChatMessage[]>(`/sessions/${sessionId}/messages`);

  const saveMessages = (sessionId: string, messages: ChatMessage[]) =>
    client.put(`/sessions/${sessionId}/messages`, messages);

  const renameSession = async (sessionId: string | null, args: string): Promise<SlashCommandResult> => {
    if (!args) return { handled: true, feedback: 'Usage: /rename <new title>' };
    if (!sessionId) return { handled: true, feedback: 'No active session to rename.' };

    const title = args.slice(0, 200);
    try {
      await client.put(`/sessions/${sessionId}`, { title });
      queryClient.setQueryData<SessionEntry[]>(
        ['SESSIONS'],
        (prev) => prev?.map((s) => (s.id === sessionId ? { ...s, title } : s)) ?? [],
      );
      return { handled: true, feedback: `Session renamed to "${title}"` };
    } catch {
      return { handled: true, feedback: 'Failed to rename session.' };
    }
  };

  const archiveSession = async (sessionId: string) => {
    await client.post(`/sessions/${sessionId}/archive`);
    queryClient.setQueryData<SessionEntry[]>(['SESSIONS'], (prev) => prev?.filter((s) => s.id !== sessionId) ?? []);
  };

  const deleteSession = async (sessionId: string) => {
    await client.delete(`/sessions/${sessionId}`);
    queryClient.setQueryData<SessionEntry[]>(['SESSIONS'], (prev) => prev?.filter((s) => s.id !== sessionId) ?? []);
  };

  return { sessions, getMessages, saveMessages, renameSession, archiveSession, deleteSession };
};