import { ref, watchEffect, computed, watch } from 'vue';
import { Message } from 'element-ui';
import { getFileType } from '@/utils/filter';
import { fileUploadAbort } from '@/api/app';

export const pictureFormat = ['webp', 'jpg', 'jpeg', 'gif', 'png', 'tif'];
export const audioFormat = ['mp3', 'wma'];
export const videoFormat = ['mp4', 'flv', 'webm', 'mpeg', 'mpg'];
export const documentFormat = ['txt', 'doc', 'docx', 'pdf', 'ppt', 'pptx', 'xls', 'xlsx'];
export const compressFormat = ['zip', 'rar', '7z'];
export const allowFormat = pictureFormat.concat(audioFormat, videoFormat, documentFormat, compressFormat); // 所有允许的文件格式

export let accept = `.${allowFormat.join(',.')}`;

// 文件状态列表
export const fileStatusList = [
  {
    name: '文件格式有误',
    type: 'error',
    icon: 'error-circle-filled'
  },
  {
    name: '待上传',
    type: 'wait',
    icon: 'time-filled'
  },
  {
    name: '上传中',
    type: 'uploading',
    icon: 'loading-blue'
  },
  {
    name: '上传成功',
    type: 'success',
    icon: 'check-circle-filled',
    id: ''
  }
];

// 是否为允许的文件格式
export function allowFileFormat(suffix) {
  return allowFormat.includes(suffix);
}

/**
 * 上传文件
 * @param {ref} file <input type="file" /> 的 refs
 * @param {Object} curTemplateData 当前模板数据
 */
export function useUploadFile(file, curTemplateData) {
  let files = ref(curTemplateData['_files']);

  let file_id_list = computed(() => {
    return files.value
      .filter(({ status: { type } }) => type === fileStatusList[3].type)
      .map(({ status: { id } }) => id);
  });

  watch(
    () => file_id_list.value,
    () => {
      curTemplateData.file_id_list = file_id_list.value;
    },
    { immediate: true }
  );

  // 打开选择文件
  function uploadFile() {
    file.value.value = null;
    file.value.click();
  }

  // 添加到文件列表
  function pushFiles(fileList) {
    for (const el of fileList) {
      files.value.push({
        file: el,
        status: allowFileFormat(getFileType(el.name)) ? fileStatusList[1] : fileStatusList[0]
      });
    }
  }

  function dropFiles(data) {
    pushFiles(data.files);
  }

  function handleFiles({ target }) {
    pushFiles(target.files);
  }

  // 删除文件
  function deleteFile(i) {
    files.value.splice(i, 1);
  }

  // 上传文件和中断处理
  let controllerFn = ref(null); // 中断上传函数
  let isBreak = ref(false); // 是否中断
  let fileNum = 0; // 当前上传的文件索引
  let uploading = ref(false); // 是否上传中
  async function* handleUpload() {
    for (fileNum; fileNum < files.value.length; fileNum++) {
      if (isBreak.value) return;
      let { status, file } = files.value[fileNum];
      if (status.type !== fileStatusList[1].type) continue;
      let formData = new FormData();
      formData.append(file.name, file, file.name);
      const { request, progress, controller } = fileUploadAbort('Mid', formData);
      const stop = watchEffect(() => {
        files.value[fileNum].status = Object.assign({}, fileStatusList[2], { name: `上传${progress.value}%...` });
      });
      controllerFn.value = controller;
      yield request;
      stop();
    }
  }

  async function upload() {
    if (uploading.value) {
      return Message.warning('上传文件中');
    }
    if (files.value.length <= 0) {
      return Message.warning('请先选择文件');
    }
    if (!files.value.some(({ status: { type } }) => type === fileStatusList[1].type)) {
      return Message.warning('没有需要上传的文件');
    }
    fileNum = 0;
    isBreak.value = false;
    uploading.value = true;
    for await (let data of handleUpload()) {
      if ('file_info_list' in data) {
        files.value[fileNum].status = { ...fileStatusList[3], id: data.file_info_list?.[0].file_id };
      }
    }
    fileNum = 0;
    controllerFn.value = null;
    uploading.value = false;
  }

  // 中断上传
  function breakUpload() {
    if (!controllerFn.value) {
      return Message.warning('没有上传中的文件');
    }
    isBreak.value = true;
    controllerFn.value.abort();
    uploading.value = false;
    files.value[fileNum].status = fileStatusList[1];
  }

  return {
    files,
    uploadFile,
    handleFiles,
    dropFiles,
    deleteFile,
    upload,
    breakUpload
  };
}

/**
 * 获取文件图标
 * @param {string} type 文件类型
 */
export function getFileImage(type) {
  if (type === 'txt') {
    return require('@/assets/file/txt-bc.png');
  }
  if (type === 'pdf') {
    return require('@/assets/file/pdf-bc.png');
  }
  if (/^xlsx?$/.test(type)) {
    return require('@/assets/file/execl-bc.png');
  }
  if (/^pptx?$/.test(type)) {
    return require('@/assets/file/ppt-bc.png');
  }
  if (/^docx?$/.test(type)) {
    return require('@/assets/file/word-bc.png');
  }
}