/* eslint-disable @typescript-eslint/ban-ts-comment */
import { ref, Ref, watch, WatchSource, onUnmounted, computed } from 'vue';

export interface UseRequestReturn<T> {
  /** 纯净的数据，不包含后端外层壳 */
  data: Ref<T | undefined>;
  /** 加载状态 */
  loading: Ref<boolean>;
  /** 错误对象 */
  error: Ref<Error | null>;
  /** 手动触发请求 */
  run: (...args: any[]) => Promise<T | undefined>;
  /** 取消请求 */
  cancel: () => void;
  /** 重置数据 */
  reset: () => void;
}

export function useRequest<T>(
  fetcher: (...args: any[]) => Promise<any>,
  options: {
    /** 是否手动触发，默认 false (即自动触发) */
    manual?: boolean;
    /** 初始数据 */
    initialData?: T;
    /** 依赖数组，变化时重新请求 */
    refreshDeps?: WatchSource[];
    /**
     * 数据格式化函数
     * 默认逻辑：如果返回是对象且有 data 属性，则返回 res.data，否则返回原数据
     */
    formatResult?: (res: any) => T;
    /** 是否准备好可以发起请求，默认 true */
    ready?: Ref<boolean>;
  } = {},
): UseRequestReturn<T> & {
  /** 获取当前 AbortController 的 signal，可传递给 fetcher */
  getSignal: () => AbortSignal | undefined;
} {
  const {
    manual = false,
    initialData,
    refreshDeps,
    formatResult = (res) => (res && typeof res === 'object' && 'data' in res ? res.data : res),
    ready = ref(true),
  } = options;

  const data = ref<T | undefined>(initialData);
  const loading = ref(false);
  const error = ref<Error | null>(null);

  let abortController: AbortController | null = null;
  let isUnmounted = false;

  onUnmounted(() => {
    isUnmounted = true;
    if (abortController) {
      abortController.abort();
    }
  });

  const run = async (...args: any[]): Promise<T | undefined> => {
    if (isUnmounted) return undefined;

    // 取消之前的请求
    if (abortController) {
      abortController.abort();
    }

    // 创建新的 AbortController
    abortController = new AbortController();
    const currentSignal = abortController.signal;

    loading.value = true;
    error.value = null;

    try {
      // 将 signal 作为最后一个参数传递给 fetcher
      // 调用方可以通过最后一个参数获取 signal: async (...args, { signal }) => {...}
      const res = await fetcher(...args, { signal: currentSignal });

      if (currentSignal.aborted || isUnmounted) {
        return undefined;
      }

      const formattedData = formatResult(res);

      if (!isUnmounted) {
        data.value = formattedData;
      }

      return formattedData;
    } catch (e: any) {
      if (e.name === 'AbortError' || e.message?.includes('aborted')) {
        return undefined;
      }
      if (!isUnmounted) {
        error.value = e;
      }
      return undefined;
    } finally {
      // 只有当前请求未被取消时才重置 loading
      if (!currentSignal.aborted && !isUnmounted) {
        loading.value = false;
      }
      // 如果这是当前活动的 controller，清理引用
      if (abortController?.signal === currentSignal) {
        abortController = null;
      }
    }
  };

  const cancel = () => {
    if (abortController) {
      abortController.abort();
      loading.value = false;
      abortController = null;
    }
  };

  const reset = () => {
    cancel();
    data.value = initialData;
    error.value = null;
  };

  // 使用 shouldAutoRun 统一管理自动请求，避免 refreshDeps 和 immediate watch 重复触发 run
  const shouldAutoRun = computed(() => !manual && ready.value);
  let hasAutoRun = false; // 标记是否已自动执行过，防止重复触发

  watch(
    shouldAutoRun,
    (val) => {
      if (val && !hasAutoRun) {
        hasAutoRun = true;
        run();
      } else if (!val) {
        // 当条件不满足时重置 hasAutoRun，使下次满足条件时能再次自动执行
        hasAutoRun = false;
      }
    },
    { immediate: true },
  );

  // refreshDeps 变化时重新请求（初始化时不再重复触发）
  if (refreshDeps && refreshDeps.length > 0) {
    watch(
      refreshDeps,
      () => {
        if (shouldAutoRun.value) {
          run();
        }
      },
      { deep: true },
    );
  }

  const getSignal = () => abortController?.signal;

  return {
    // @ts-ignore
    data,
    loading,
    error,
    run,
    cancel,
    reset,
    getSignal,
  };
}