import { getUrlType } from './meta';

// 加载第三方库
export const loadLib = (() => {
  const cache: Record<string, Promise<void>> = {};

  const load = (
    lib: string,
    success: () => void,
    err: () => void,
    maxReq = 0
  ) => {
    const el = document.createElement("script");
    el.src = lib;
    document.body.appendChild(el);
    el.onload = success;
    el.onerror = () => {
      if (maxReq > 0) {
        load(lib, success, err, --maxReq);
      } else {
        err();
      }
    };
  };

  return (lib: string) => {
    if (!cache[lib]) {
      cache[lib] = new Promise((resolve, reject) => {
        load(lib, resolve, reject, 3);
      });
    }
    return cache[lib];
  };
})();


export const getSizeStr = (size: number) => {
  let mb = size;
  if (mb < 1024) {
    return `${mb.toFixed(2)}BYTE`;
  }
  mb /= 1024;
  if (mb < 1024) {
    return `${mb.toFixed(2)}KB`;
  }
  mb /= 1024;
  if (mb < 1024) {
    return `${mb.toFixed(2)}MB`;
  }
  mb /= 1024;
  if (mb < 1024) {
    return `${mb.toFixed(2)}GB`;
  }
  mb /= 1024;
  return `${mb.toFixed(2)}TB`;
};

export const togetherCallback = (cbs: (() => void)[]) => () => together(cbs)

export const together = (cbs: (() => void)[]) => {
  cbs.forEach(cb => cb())
}

export const getFileUrl = (file: LocalFile | string) => 
  typeof file === 'string'
    ? file
    : file.url
export const getFileName = (file: any): string => {

  return typeof file === 'string'
    ? file.substring(file.indexOf('/') + 1)
    : file.blob instanceof File ? file.blob.name : getUrlType(file.url)
}

export const asyncTimeout = (mis: number = 0) => new Promise(resolve => setTimeout(resolve, mis))


export const jsonToForm = (data: { [key in string]: any }) => {
  const formData = new FormData()
  for (const [key, val] of Object.entries(data)) {
    if (Array.isArray(val)) {
      for (let i = 0; i < val.length; i++) {
        formData.append(`${key}`, val[i])  
      }
    } else {
      formData.append(key, val)
    }
  }
  return formData
}


// 防抖
export const debounce = <T extends (...args: any) => any>(
	fn: T,
	delay: number = 160
) => {
	let timeout: any;
	return function (...args: Parameters<T>) {
		clearTimeout(timeout);
		timeout = setTimeout(() => {
			fn.apply(null, args);
		}, delay);
	};
};

// 防抖
export const debounceStack = <T extends (...args: any) => any>(
	fn: T,
  success: (data: ReturnType<T> extends Promise<infer P> ? P : ReturnType<T>) => void,
	delay: number = 160
) => {
  let dsToken = 0
  return debounce(async (...args: Parameters<T>) => {
    ++dsToken
    const currentToken = dsToken
    const result = await fn.apply(null, args);
    if (currentToken === dsToken) {    
      success(result)
    }
  }, delay)
};


// 四舍五入保留指定位数
export const round = (num: number, index: number = 2) => {
  const s = Math.pow(10, index)
  return Math.round(num * s) / s
}

export * from './store-help'
export * from "./stack";
export * from "./loading";
export * from "./route";
export * from "./asyncBus";
export * from './mount'
export * from './watch'
export * from './diff'
export * from './params'
export * from './file-serve'
export * from './video-cover'
export * from './meta'