import React, { useCallback, useMemo, useRef } from 'react';
import { Image } from 'antd';

import type { UploadData } from '../../index';
import type { PicConfig } from '../index';

export interface PicListProps extends PicConfig {
  value?: UploadData[];
}

const defaultSrc =
  'data:image/png;base64,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';

export function List(props: PicListProps) {
  const objUrlMap = useRef<Map<File, string>>(new Map());
  const getObjUrl = useCallback((file: File) => {
    let objUrl = objUrlMap.current.get(file);
    if (!objUrl) {
      objUrl = URL.createObjectURL(file);
      objUrlMap.current.set(file, objUrl);
    }
    return objUrl;
  }, []);

  // 是否有自定义空值
  const hasEmpty = useMemo(
    () => props.empty !== null && props.empty !== undefined,
    [props.empty]
  );

  // 默认图片地址url（加载出错或者空值）
  const fallback = useMemo(
    () => props.fallback || defaultSrc,
    [props.fallback]
  );

  // 图片配置
  const imgConfig = useMemo(() => {
    const data = { ...props };
    Reflect.deleteProperty(data, 'empty');
    Reflect.deleteProperty(data, 'value');
    Reflect.deleteProperty(data, 'fallback');
    return data;
  }, [props]);

  const value = useMemo(() => {
    const data = props.value || [];
    const result: string[] = [];
    data.forEach((item) => {
      if (!hasEmpty || Boolean(item)) {
        let url = '';
        if (typeof item === 'string') url = item;
        else if (item.originFileObj) url = getObjUrl(item.originFileObj);
        result.push(url);
      }
    });

    if (hasEmpty) return result;
    if (!result.length) result.push('');
    return result;
  }, [props.value, hasEmpty, getObjUrl]);

  return (
    <Image.PreviewGroup>
      {value.length > 0
        ? value.map((item, index) => (
            <Image
              key={item || index}
              {...imgConfig}
              rootClassName={'ft-pic-item ' + (imgConfig.rootClassName || '')}
              src={item}
              fallback={fallback}
            />
          ))
        : props.empty}
    </Image.PreviewGroup>
  );
}