<template>
  <div class="component-upload-image">
    <el-row>
      <draggable
          v-if="fileList.length > 1"
          v-model="fileList"
          item-key="index"
          @end="draggableEnd"
      >
        <template #item="{ element }">
          <div class="fileItem el-upload-list__item is-success animated">
            <img
                :src="element.url"
                alt=""
                class="el-upload-list__item-thumbnail"
            >
            <div class="hover-actions">
              <span @click="handlePictureCardPreview(element)">
                <el-icon><ZoomIn/></el-icon>
              </span>
              <span v-if="!disabled" @click="handleDelete(element)">
                <el-icon><Delete/></el-icon>
              </span>
            </div>
          </div>
        </template>
      </draggable>
      <el-upload
          ref="imageUpload"
          :multiple="limit > 1"
          :action="actionUrl || uploadImgUrl"
          :list-type="listType"
          :on-success="handleUploadSuccess"
          :before-upload="handleBeforeUpload"
          :limit="limit"
          :on-error="handleUploadError"
          :on-exceed="handleExceed"
          :before-remove="handleDelete"
          :show-file-list="showFileList"
          :headers="headers"
          :on-preview="handlePictureCardPreview"
          :file-list="fileListInUpload"
          :class="{ hide: fileList.length >= limit }"
          :name="paramName"
          :disabled="disabled"
          :accept="accept"
      >
        <el-icon v-if="listType=='picture-card'" class="avatar-uploader-icon">
          <plus/>
        </el-icon>
        <el-link v-else class="mr10" type="primary">
          <el-icon>
            <Upload/>
          </el-icon>
          {{ buttonText }}
        </el-link>
      </el-upload>
    </el-row>

    <!-- 上传提示 -->
    <div v-if="showTip && fileList.length < limit" class="el-upload__tip">
      请上传
      <template v-if="fileSize">
        大小不超过
        <b style="color: #f56c6c">{{ fileSize }}MB</b>
      </template>
      <template v-if="fileType">
        格式为
        <b style="color: #f56c6c">{{ fileType.join("/") }}</b>
      </template>
      的文件
    </div>

    <el-dialog
        v-model="dialogVisible"
        title="预览"
        width="800px"
        append-to-body
    >
      <img
          :src="dialogImageUrl"
          style="display: block; max-width: 100%; margin: 0 auto"
      >
    </el-dialog>
  </div>
</template>

<script setup>
import {getToken} from '@/utils/auth'
import {computed, getCurrentInstance, ref, watch} from 'vue'
import _ from 'lodash'
import {useStorage} from "@vueuse/core";

const props = defineProps({
  modelValue: [String, Object, Array],
  // 图片数量限制
  limit: {
    type: Number,
    default: 5
  },
  // 大小限制(MB)
  fileSize: {
    type: Number,
    default: 5
  },
  paramName: {
    type: String,
    default: 'image'
  },
  listType: {
    type: String,
    default: 'picture-card'
  },
  // 文件类型, 例如['png', 'jpg', 'jpeg']
  fileType: {
    type: Array,
    default: () => ['png', 'jpg', 'jpeg']
  },
  // 是否显示提示
  isShowTip: {
    type: Boolean,
    default: true
  },
  disabled: {
    type: Boolean,
    default: false
  },
  showFileList: {
    type: Boolean,
    default: true
  },
  action: {
    type: String,
    default: ''
  },
  buttonText: {
    type: String,
    default: '上传文件'
  }
})
const actionUrl = computed(() => {
  return props.action ? baseUrl + props.action : ''
})
const accept = computed(() => {
  return _.map(props.fileType, (t) => {
    if (t.indexOf('.') === 0) {
      return t
    } else {
      return '.' + t
    }
  }).join(',')
})

const {proxy} = getCurrentInstance()
const emit = defineEmits(['update:modelValue', 'response'])
const number = ref(0)
const uploadList = ref([])
const dialogImageUrl = ref('')
const dialogVisible = ref(false)
const baseUrl = import.meta.env.VITE_APP_BASE_API
const uploadImgUrl = ref(
    baseUrl + '/upload/uploadImgToLocalServer'
) // 上传的图片服务器地址
const headers = ref({Authorization: 'Bearer ' + getToken()})
const fileList = ref([])
const fileListInUpload = ref([])
const showTip = computed(
    () => props.isShowTip && (props.fileType || props.fileSize)
)
const language = useStorage('language', 0)


watch(
    () => props.modelValue,
    (val) => {
      if (val) {
        // 首先将值转为数组
        const list = Array.isArray(val) ? val : props.modelValue.split(',')
        // 然后将数组转为对象数组
        fileList.value = list.map((item) => {
          if (typeof item === 'string') {
            if (item.indexOf('http') === -1) {
              item = {name: item, url: baseUrl + item}
            } else {
              item = {name: item, url: item}
            }
          }
          return item
        })
        if (fileList.value.length == 1) {
          fileListInUpload.value = fileList.value
        }
      } else {
        fileList.value = []
        return []
      }
    },
    {deep: true, immediate: true}
)

// 上传前loading加载
function handleBeforeUpload(file) {
  let isImg = false
  if (props.fileType.length) {
    let fileExtension = ''
    if (file.name.lastIndexOf('.') > -1) {
      fileExtension = file.name.slice(file.name.lastIndexOf('.') + 1)
    }
    isImg = props.fileType.some((type) => {
      if (file.type.indexOf(type) > -1) return true
      if (fileExtension && fileExtension.indexOf(type) > -1) return true
      return false
    })
  } else {
    isImg = file.type.indexOf('image') > -1
  }
  if (!isImg) {
    proxy.$modal.msgError(
        language.value == 0 ?
            `文件格式不正确, 请上传${props.fileType.join('/')}图片格式文件!` :
            `The file format is incorrect, please upload ${props.fileType.join('/')} image format file!`
    )
    return false
  }
  if (props.fileSize) {
    const isLt = file.size / 1024 / 1024 < props.fileSize
    if (!isLt) {
      proxy.$modal.msgError(
          language.value == 0 ?
              `上传图片大小不能超过 ${props.fileSize} MB!` :
              `Upload image size cannot exceed ${props.fileSize} MB!`
      )
      return false
    }
  }
  proxy.$modal.loading(language.value == 0 ? '正在上传图片，请稍候...' : 'Uploading images, please wait...')
  number.value++
}

// 文件个数超出
function handleExceed() {
  proxy.$modal.msgError(language.value == 0 ? `上传文件数量不能超过 ${props.limit} 个!` : `Maximum file count: ${props.limit}`)
}

// 上传成功回调
function handleUploadSuccess(res, file) {
  if (!actionUrl.value) {
    if (res.code === 200) {
      uploadList.value.push({name: file.name, url: res.data || res.msg})
      uploadedSuccessfully()
    } else {
      number.value--
      proxy.$modal.closeLoading()
      proxy.$modal.msgError(res.msg)
      proxy.$refs.imageUpload.handleRemove(file)
      uploadedSuccessfully()
    }
  } else {
    proxy.$modal.closeLoading()
    emit('response', res)
  }
}

// 删除图片
function handleDelete(file) {
  const findex = fileList.value.map((f) => f.name).indexOf(file.name)
  if (findex > -1 && uploadList.value.length === number.value) {
    fileList.value.splice(findex, 1)
    emit('update:modelValue', listToString(fileList.value))
    return false
  }
}

// 上传结束处理
function uploadedSuccessfully() {
  if (number.value > 0 && uploadList.value.length === number.value) {
    fileList.value = fileList.value
        .filter((f) => f.url !== undefined)
        .concat(uploadList.value)
    uploadList.value = []
    number.value = 0
    emit('update:modelValue', listToString(fileList.value))
    proxy.$modal.closeLoading()

    if (fileList.value.length > 1) {
      fileListInUpload.value = []
    }
  }
}

// 上传失败
function handleUploadError() {
  proxy.$modal.msgError(language.value == 0 ? '上传图片失败' : 'Upload failed')
  proxy.$modal.closeLoading()
}

// 预览
function handlePictureCardPreview(file) {
  dialogImageUrl.value = file.url
  dialogVisible.value = true
}

// 对象转成指定字符串分隔
function listToString(list, separator) {
  let strs = ''
  separator = separator || ','
  for (const i in list) {
    if (undefined !== list[i].url && list[i].url.indexOf('blob:') !== 0) {
      strs += list[i].url.replace(baseUrl, '') + separator
    }
  }
  return strs != '' ? strs.substr(0, strs.length - 1) : ''
}

function draggableEnd() {
  emit('update:modelValue', listToString(fileList.value))
}
</script>

<style scoped lang="scss">
// .el-upload--picture-card 控制加号部分
:deep(.hide .el-upload--picture-card) {
  display: none;
}

.fileItem {
  position: relative;
  width: 160px;
  height: 160px;
  overflow: hidden;
  margin: 0 20px 20px 0;
  float: left;
}

.fileItem img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.fileItem .hover-actions {
  background: rgba(0, 0, 0, 0.4);
  width: 100%;
  height: 100%;
  position: absolute;
  top: 100%;
  left: 0;
  color: #fff;
  transition: top 0.2s;
  text-align: center;

  span {
    cursor: pointer;
    font-size: 26px;
    padding: 10px;
    margin: 50px 5px;
    display: inline-block;
  }

  span:hover {
    background: rgba(255, 255, 255, 0.4);
  }
}

.fileItem:hover .hover-actions {
  top: 0;
}
</style>