import { useState, useCallback, useEffect } from 'react'
import type { Task, CreateTaskRequest, ApiError } from '~/types/task'
import { TaskStatus } from '~/types/task'
import { apiClient } from '~/services/api'

interface UseTasksState {
  tasks: Task[]
  loading: boolean
  error: string | null
  lastFetch: Date | null
}

interface UseTasksActions {
  fetchTasks: () => Promise<void>
  createTask: (data: CreateTaskRequest) => Promise<Task | null>
  refreshTasks: () => Promise<void>
  clearError: () => void
  getTaskById: (id: string) => Task | undefined
  filterTasksByStatus: (status: TaskStatus) => Task[]
}

interface UseTasksOptions {
  autoFetch?: boolean
  refreshInterval?: number
}

export function useTasks(
  options: UseTasksOptions = {}
): UseTasksState & UseTasksActions {
  const { autoFetch = true, refreshInterval } = options

  const [state, setState] = useState<UseTasksState>({
    tasks: [],
    loading: false,
    error: null,
    lastFetch: null,
  })

  const clearError = useCallback(() => {
    setState(prev => ({ ...prev, error: null }))
  }, [])

  const fetchTasks = useCallback(async () => {
    setState(prev => ({ ...prev, loading: true, error: null }))

    try {
      const tasks = await apiClient.listTasks()
      setState(prev => ({
        ...prev,
        tasks,
        loading: false,
        lastFetch: new Date(),
      }))
    } catch (error) {
      const apiError = error as ApiError
      setState(prev => ({
        ...prev,
        loading: false,
        error: apiError.message,
      }))
    }
  }, [])

  const createTask = useCallback(
    async (data: CreateTaskRequest): Promise<Task | null> => {
      setState(prev => ({ ...prev, loading: true, error: null }))

      try {
        const newTask = await apiClient.createTask(data)

        // Add the new task to the beginning of the list (most recent first)
        setState(prev => ({
          ...prev,
          tasks: [newTask, ...prev.tasks],
          loading: false,
        }))

        return newTask
      } catch (error) {
        const apiError = error as ApiError
        setState(prev => ({
          ...prev,
          loading: false,
          error: apiError.message,
        }))
        return null
      }
    },
    []
  )

  const refreshTasks = useCallback(async () => {
    // Force refresh without showing loading state if tasks already exist
    const showLoading = state.tasks.length === 0

    if (showLoading) {
      setState(prev => ({ ...prev, loading: true, error: null }))
    } else {
      setState(prev => ({ ...prev, error: null }))
    }

    try {
      const tasks = await apiClient.listTasks()
      setState(prev => ({
        ...prev,
        tasks,
        loading: false,
        lastFetch: new Date(),
      }))
    } catch (error) {
      const apiError = error as ApiError
      setState(prev => ({
        ...prev,
        loading: false,
        error: apiError.message,
      }))
    }
  }, [state.tasks])

  const getTaskById = useCallback(
    (id: string): Task | undefined => {
      return state.tasks.find(task => task.id === id)
    },
    [state.tasks]
  )

  const filterTasksByStatus = useCallback(
    (status: TaskStatus): Task[] => {
      return state.tasks.filter(task => task.status === status)
    },
    [state.tasks]
  )

  // Auto-fetch tasks on mount
  useEffect(() => {
    if (autoFetch) {
      fetchTasks()
    }
  }, [autoFetch, fetchTasks])

  // Set up refresh interval if specified
  useEffect(() => {
    if (!refreshInterval) return

    const interval = setInterval(() => {
      refreshTasks()
    }, refreshInterval)

    return () => clearInterval(interval)
  }, [refreshInterval, refreshTasks])

  return {
    ...state,
    fetchTasks,
    createTask,
    refreshTasks,
    clearError,
    getTaskById,
    filterTasksByStatus,
  }
}