import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import { tasksApi } from '@/lib/api/pm';
import type { Task, CreateTaskDto, UpdateTaskDto, WorkItemStatus } from '@/types/project';
import { toast } from 'sonner';
import { logger } from '@/lib/utils/logger';

// ==================== Query Hooks ====================
export function useTasks(storyId?: string) {
  return useQuery<Task[]>({
    queryKey: ['tasks', storyId],
    queryFn: async () => {
      logger.debug('[useTasks] Fetching tasks...', { storyId });
      try {
        const result = await tasksApi.list(storyId);
        logger.debug('[useTasks] Fetch successful:', result);
        return result;
      } catch (error) {
        logger.error('[useTasks] Fetch failed:', error);
        throw error;
      }
    },
    staleTime: 5 * 60 * 1000, // 5 minutes
    retry: 1,
  });
}

export function useTask(id: string) {
  return useQuery<Task>({
    queryKey: ['tasks', id],
    queryFn: () => tasksApi.get(id),
    enabled: !!id,
  });
}

// ==================== Mutation Hooks ====================
export function useCreateTask() {
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: (data: CreateTaskDto) => tasksApi.create(data),
    onSuccess: (newTask) => {
      // Invalidate all task queries
      queryClient.invalidateQueries({ queryKey: ['tasks'] });

      // Also invalidate story details
      queryClient.invalidateQueries({ queryKey: ['stories', newTask.storyId] });

      toast.success('Task created successfully!');
    },
    onError: (error: any) => {
      logger.error('[useCreateTask] Error:', error);
      toast.error(error.response?.data?.detail || 'Failed to create task');
    },
  });
}

export function useUpdateTask() {
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: ({ id, data }: { id: string; data: UpdateTaskDto }) =>
      tasksApi.update(id, data),
    onMutate: async ({ id, data }) => {
      await queryClient.cancelQueries({ queryKey: ['tasks', id] });

      const previousTask = queryClient.getQueryData<Task>(['tasks', id]);

      queryClient.setQueryData<Task>(['tasks', id], (old) => ({
        ...old!,
        ...data,
      }));

      return { previousTask };
    },
    onError: (error: any, variables, context) => {
      logger.error('[useUpdateTask] Error:', error);

      if (context?.previousTask) {
        queryClient.setQueryData(['tasks', variables.id], context.previousTask);
      }

      toast.error(error.response?.data?.detail || 'Failed to update task');
    },
    onSuccess: () => {
      toast.success('Task updated successfully!');
    },
    onSettled: (_, __, variables) => {
      queryClient.invalidateQueries({ queryKey: ['tasks', variables.id] });
      queryClient.invalidateQueries({ queryKey: ['tasks'] });
    },
  });
}

export function useDeleteTask() {
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: (id: string) => tasksApi.delete(id),
    onSuccess: (_, id) => {
      queryClient.invalidateQueries({ queryKey: ['tasks'] });
      queryClient.removeQueries({ queryKey: ['tasks', id] });
      toast.success('Task deleted successfully!');
    },
    onError: (error: any) => {
      logger.error('[useDeleteTask] Error:', error);
      toast.error(error.response?.data?.detail || 'Failed to delete task');
    },
  });
}

export function useChangeTaskStatus() {
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: ({ id, status }: { id: string; status: WorkItemStatus }) =>
      tasksApi.changeStatus(id, status),
    onMutate: async ({ id, status }) => {
      await queryClient.cancelQueries({ queryKey: ['tasks', id] });

      const previousTask = queryClient.getQueryData<Task>(['tasks', id]);

      queryClient.setQueryData<Task>(['tasks', id], (old) => ({
        ...old!,
        status,
      }));

      return { previousTask };
    },
    onError: (error: any, variables, context) => {
      logger.error('[useChangeTaskStatus] Error:', error);

      if (context?.previousTask) {
        queryClient.setQueryData(['tasks', variables.id], context.previousTask);
      }

      toast.error(error.response?.data?.detail || 'Failed to change task status');
    },
    onSuccess: () => {
      toast.success('Task status changed successfully!');
    },
    onSettled: (_, __, variables) => {
      queryClient.invalidateQueries({ queryKey: ['tasks', variables.id] });
      queryClient.invalidateQueries({ queryKey: ['tasks'] });
    },
  });
}

export function useAssignTask() {
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: ({ id, assigneeId }: { id: string; assigneeId: string }) =>
      tasksApi.assign(id, assigneeId),
    onSuccess: (_, variables) => {
      queryClient.invalidateQueries({ queryKey: ['tasks', variables.id] });
      queryClient.invalidateQueries({ queryKey: ['tasks'] });
      toast.success('Task assigned successfully!');
    },
    onError: (error: any) => {
      logger.error('[useAssignTask] Error:', error);
      toast.error(error.response?.data?.detail || 'Failed to assign task');
    },
  });
}