pdf-reader-web/reducers/middleware/index.ts

/* eslint-disable @typescript-eslint/camelcase */
import { Dispatch } from 'react';
import { CHANGE_SCALE, TOGGLE_DISPLAY_MODE } from '../../constants/actionTypes';

const applyMiddleware = (
  state: any, dispatch: Dispatch<any>,
) => (
  action: { type: string; payload?: any },
): void => {
  dispatch(action);
  switch (action.type) {
    case TOGGLE_DISPLAY_MODE: {
      if (action.payload === 'full') {
        const screenWidth = window.document.body.offsetWidth - 5;
        const originPdfWidth = state.viewport.width / state.scale;
        const rate = (screenWidth / originPdfWidth).toFixed(2);
        dispatch({ type: CHANGE_SCALE, payload: rate });
      } else {
        dispatch({ type: CHANGE_SCALE, payload: 1 });
      }
      break;
    }
    default:
      break;
  }
};

export default applyMiddleware;