smart-table-keyboard/lib/keygrid.js

provide keyboard navigation to widget implementing the grid pattern

import {createCell} from './cell';
import {createRow} from './row';
import {findContainer} from './util';

export function keyGrid (grid, options) {
  const {rowSelector, cellSelector} = options;
  return {
    moveRight(target){
      const cell = createCell(target, options);
      let newCell = createCell(cell.next(), options);
      while (newCell !== null && newCell.selectFromBefore === void 0) {
        newCell = createCell(newCell.next(), options);
      }
      return newCell !== null ? newCell.selectFromBefore() : target;
    },
    moveLeft(target){
      const cell = createCell(target, options);
      let newCell = createCell(cell.previous(), options);
      while (newCell !== null && newCell.selectFromAfter === void 0) {
        newCell = createCell(newCell.previous(), options);
      }
      return newCell !== null ? newCell.selectFromAfter() : target;
    },
    moveUp(target){
      const rowElement = findContainer(target, rowSelector);
      const cells = [...rowElement.querySelectorAll(cellSelector)];
      const row = createRow(rowElement, grid, options);
      let newRow = createRow(row.previous(), grid, options);
      while (newRow !== null && newRow.item === void 0) {
        newRow = createRow(newRow.previous(), grid, options);
      }

      if (newRow === null) {
        return target;
      }

      let askedIndex = cells.indexOf(findContainer(target, cellSelector));
      let newCell = createCell(newRow.item(askedIndex), options);
      while (newCell === null || newCell.selectFromBefore === void 0 && askedIndex > 0) {
        askedIndex--;
        newCell = createCell(newRow.item(askedIndex), options);
      }
      return newCell.selectFromBefore();
    },
    moveDown(target){
      const rowElement = findContainer(target, rowSelector);
      const cells = [...rowElement.querySelectorAll(cellSelector)];
      const row = createRow(rowElement, grid, options);
      let newRow = createRow(row.next(), grid, options);
      while (newRow !== null && newRow.item === void 0) {
        newRow = createRow(newRow.next(), grid, options);
      }

      if (newRow === null) {
        return target;
      }

      let askedIndex = cells.indexOf(findContainer(target, cellSelector));
      let newCell = createCell(newRow.item(askedIndex), options);
      while (newCell === null || newCell.selectFromBefore === void 0 && askedIndex > 0) {
        askedIndex--;
        newCell = createCell(newRow.item(askedIndex), options);
      }
      return newCell.selectFromBefore();
    }
  }
}