import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import { useNavigate } from "@tanstack/react-router";

import { agentsApi } from "./api";
import { addPendingPrompt } from "./pendingPrompts";

export const agentThreadKeys = {
  all: ["agent-threads"] as const,
  detail: (threadId: string) => ["agent-threads", threadId] as const,
};

export function useAgentThreads() {
  return useQuery({
    queryKey: agentThreadKeys.all,
    queryFn: () => agentsApi.listThreads(),
  });
}

export function useAgentThread(threadId: string) {
  return useQuery({
    queryKey: agentThreadKeys.detail(threadId),
    queryFn: () => agentsApi.getThread(threadId),
    refetchInterval: (query) => {
      const status = query.state.data?.status;
      return status === "running" ? 2000 : false;
    },
  });
}

export function useCreateAgentThread() {
  const queryClient = useQueryClient();
  const navigate = useNavigate();

  return useMutation({
    mutationFn: agentsApi.createThread,
    onSuccess: (thread, variables) => {
      addPendingPrompt(thread.id, variables.prompt, thread.messages.length);
      queryClient.setQueryData(agentThreadKeys.detail(thread.id), {
        ...thread,
        status: thread.status === "idle" ? "running" : thread.status,
      });
      queryClient.invalidateQueries({ queryKey: agentThreadKeys.all });
      navigate({ to: "/agents/$threadId", params: { threadId: thread.id } });
    },
  });
}

export interface SendAgentMessageVariables {
  content: string;
  model_id?: string | null;
  effort?: string | null;
}

export function useSendAgentMessage(threadId: string) {
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: (vars: SendAgentMessageVariables) =>
      agentsApi.sendMessage(threadId, {
        content: vars.content,
        model_id: vars.model_id,
        effort: vars.effort,
      }),
    onMutate: (vars) => {
      const cached = queryClient.getQueryData<{ messages?: unknown[] }>(
        agentThreadKeys.detail(threadId),
      );
      const insertAt = Array.isArray(cached?.messages) ? cached.messages.length : 0;
      addPendingPrompt(threadId, vars.content, insertAt);
    },
    onSuccess: (thread) => {
      queryClient.setQueryData(agentThreadKeys.detail(threadId), (prev: typeof thread | undefined) => {
        if (!prev) return thread;
        return {
          ...thread,
          messages: thread.messages.length > 0 ? thread.messages : prev.messages,
        };
      });
      queryClient.invalidateQueries({ queryKey: agentThreadKeys.all });
    },
  });
}

export function useCancelAgentThread(threadId: string) {
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: () => agentsApi.cancelThread(threadId),
    onSuccess: (thread) => {
      queryClient.setQueryData(agentThreadKeys.detail(threadId), thread);
      queryClient.invalidateQueries({ queryKey: agentThreadKeys.all });
    },
  });
}

export function useDeleteAgentThread() {
  const queryClient = useQueryClient();
  const navigate = useNavigate();

  return useMutation({
    mutationFn: (threadId: string) => agentsApi.deleteThread(threadId),
    onSuccess: (_, threadId) => {
      queryClient.removeQueries({ queryKey: agentThreadKeys.detail(threadId) });
      queryClient.invalidateQueries({ queryKey: agentThreadKeys.all });
      const path = window.location.pathname;
      if (path.includes(`/agents/${threadId}`)) {
        navigate({ to: "/agents" });
      }
    },
  });
}