text: /* *
   * (c) 2016 Highsoft AS
   * Authors: Lars A. V. Cabrera
   *
   * License: www.highcharts.com/license
   */
  
  'use strict';
  
  import H from '../parts/Globals.js';
  
  var addEvent = H.addEvent,
      argsToArray = function (args) {
          return Array.prototype.slice.call(args, 1);
      },
      dateFormat = H.dateFormat,
      defined = H.defined,
      isArray = H.isArray,
      isNumber = H.isNumber,
      isObject = function (x) {
          // Always use strict mode
          return H.isObject(x, true);
      },
      merge = H.merge,
      pick = H.pick,
      wrap = H.wrap,
      Axis = H.Axis,
      Tick = H.Tick;
  
  /**
   * Set grid options for the axis labels. Requires Highcharts Gantt.
   *
   * @since     6.2.0
   * @product   gantt
   * @apioption xAxis.grid
   */
  
  /**
   * Enable grid on the axis labels. Defaults to true for Gantt charts.
   *
   * @type      {boolean}
   * @default   true
   * @since     6.2.0
   * @product   gantt
   * @apioption xAxis.grid.enabled
   */
  
  /**
   * Set specific options for each column (or row for horizontal axes) in the
   * grid. Each extra column/row is its own axis, and the axis options can be set
   * here.
   *
   * @sample gantt/demo/left-axis-table
   *         Left axis as a table
   *
   * @type      {Array<Highcharts.XAxisOptions>}
   * @apioption xAxis.grid.columns
   */
  
  /**
   * Set border color for the label grid lines.
   *
   * @type      {Highcharts.ColorString}
   * @apioption xAxis.grid.borderColor
   */
  
  /**
   * Set border width of the label grid lines.
   *
   * @type      {number}
   * @default   1
   * @apioption xAxis.grid.borderWidth
   */
  
  /**
   * Set cell height for grid axis labels. By default this is calculated from font
   * size.
   *
   * @type      {number}
   * @apioption xAxis.grid.cellHeight
   */
  
  
  // Enum for which side the axis is on.
  // Maps to axis.side
  var axisSide = {
      top: 0,
      right: 1,
      bottom: 2,
      left: 3,
      0: 'top',
      1: 'right',
      2: 'bottom',
      3: 'left'
  };
  
  /**
   * Checks if an axis is a navigator axis.
   *
   * @private
   * @function Highcharts.Axis#isNavigatorAxis
   *
   * @return {boolean}
   *         true if axis is found in axis.chart.navigator
   */
  Axis.prototype.isNavigatorAxis = function () {
      return /highcharts-navigator-[xy]axis/.test(this.options.className);
  };
  
  /**
   * Checks if an axis is the outer axis in its dimension. Since
   * axes are placed outwards in order, the axis with the highest
   * index is the outermost axis.
   *
   * Example: If there are multiple x-axes at the top of the chart,
   * this function returns true if the axis supplied is the last
   * of the x-axes.
   *
   * @private
   * @function Highcharts.Axis#isOuterAxis
   *
   * @return {boolean}
   *         true if the axis is the outermost axis in its dimension; false if not
   */
  Axis.prototype.isOuterAxis = function () {
      var axis = this,
          chart = axis.chart,
          thisIndex = -1,
          isOuter = true;
  
      chart.axes.forEach(function (otherAxis, index) {
          if (otherAxis.side === axis.side && !otherAxis.isNavigatorAxis()) {
              if (otherAxis === axis) {
                  // Get the index of the axis in question
                  thisIndex = index;
  
                  // Check thisIndex >= 0 in case thisIndex has
                  // not been found yet
              } else if (thisIndex >= 0 && index > thisIndex) {
                  // There was an axis on the same side with a
                  // higher index.
                  isOuter = false;
              }
          }
      });
      // There were either no other axes on the same side,
      // or the other axes were not farther from the chart
      return isOuter;
  };
  
  /**
   * Get the largest label width and height.
   *
   * @private
   * @function Highcharts.Axis#getMaxLabelDimensions
   *
   * @param {Highcharts.Dictionary<Highcharts.Tick>} ticks
   *        All the ticks on one axis.
   *
   * @param {Array<number|string>} tickPositions
   *        All the tick positions on one axis.
   *
   * @return {object}
   *         object containing the properties height and width.
   */
  Axis.prototype.getMaxLabelDimensions = function (ticks, tickPositions) {
      var dimensions = {
          width: 0,
          height: 0
      };
  
      tickPositions.forEach(function (pos) {
          var tick = ticks[pos],
              tickHeight = 0,
              tickWidth = 0,
              label;
  
          if (isObject(tick)) {
              label = isObject(tick.label) ? tick.label : {};
  
              // Find width and height of tick
              tickHeight = label.getBBox ? label.getBBox().height : 0;
              tickWidth = isNumber(label.textPxLength) ? label.textPxLength : 0;
  
              // Update the result if width and/or height are larger
              dimensions.height = Math.max(tickHeight, dimensions.height);
              dimensions.width = Math.max(tickWidth, dimensions.width);
          }
      });
  
      return dimensions;
  };
  
  // Add custom date formats
  H.dateFormats = {
      // Week number
      W: function (timestamp) {
          var d = new Date(timestamp),
              yearStart,
              weekNo;
  
          d.setHours(0, 0, 0, 0);
          d.setDate(d.getDate() - (d.getDay() || 7));
          yearStart = new Date(d.getFullYear(), 0, 1);
          weekNo = Math.ceil((((d - yearStart) / 86400000) + 1) / 7);
          return weekNo;
      },
      // First letter of the day of the week, e.g. 'M' for 'Monday'.
      E: function (timestamp) {
          return dateFormat('%a', timestamp, true).charAt(0);
      }
  };
  
  addEvent(
      Tick,
      'afterGetLabelPosition',
      /**
       * Center tick labels in cells.
       *
       * @private
       */
      function (e) {
          var tick = this,
              label = tick.label,
              axis = tick.axis,
              reversed = axis.reversed,
              chart = axis.chart,
              options = axis.options,
              gridOptions = (
                  (options && isObject(options.grid)) ? options.grid : {}
              ),
              labelOpts = axis.options.labels,
              align = labelOpts.align,
              // verticalAlign is currently not supported for axis.labels.
              verticalAlign = 'middle', // labelOpts.verticalAlign,
              side = axisSide[axis.side],
              tickmarkOffset = e.tickmarkOffset,
              tickPositions = axis.tickPositions,
              tickPos = tick.pos - tickmarkOffset,
              nextTickPos = (
                  isNumber(tickPositions[e.index + 1]) ?
                      tickPositions[e.index + 1] - tickmarkOffset :
                      axis.max + tickmarkOffset
              ),
              tickSize = axis.tickSize('tick', true),
              tickWidth = isArray(tickSize) ? tickSize[0] : 0,
              crispCorr = tickSize && tickSize[1] / 2,
              labelHeight,
              lblMetrics,
              lines,
              bottom,
              top,
              left,
              right;
  
          // Only center tick labels in grid axes
          if (gridOptions.enabled === true) {
  
              // Calculate top and bottom positions of the cell.
              if (side === 'top') {
                  bottom = axis.top + axis.offset;
                  top = bottom - tickWidth;
              } else if (side === 'bottom') {
                  top = chart.chartHeight - axis.bottom + axis.offset;
                  bottom = top + tickWidth;
              } else {
                  bottom = axis.top + axis.len - axis.translate(
                      reversed ? nextTickPos : tickPos
                  );
                  top = axis.top + axis.len - axis.translate(
                      reversed ? tickPos : nextTickPos
                  );
              }
  
              // Calculate left and right positions of the cell.
              if (side === 'right') {
                  left = chart.chartWidth - axis.right + axis.offset;
                  right = left + tickWidth;
              } else if (side === 'left') {
                  right = axis.left + axis.offset;
                  left = right - tickWidth;
              } else {
                  left = Math.round(axis.left + axis.translate(
                      reversed ? nextTickPos : tickPos
                  )) - crispCorr;
                  right = Math.round(axis.left + axis.translate(
                      reversed ? tickPos : nextTickPos
                  )) - crispCorr;
              }
  
              tick.slotWidth = right - left;
  
              // Calculate the positioning of the label based on alignment.
              e.pos.x = (
                  align === 'left' ?
                      left :
                      align === 'right' ?
                          right :
                          left + ((right - left) / 2) // default to center
              );
              e.pos.y = (
                  verticalAlign === 'top' ?
                      top :
                      verticalAlign === 'bottom' ?
                          bottom :
                          top + ((bottom - top) / 2) // default to middle
              );
  
              lblMetrics = chart.renderer.fontMetrics(
                  labelOpts.style.fontSize,
                  label.element
              );
              labelHeight = label.getBBox().height;
  
              // Adjustment to y position to align the label correctly.
              // Would be better to have a setter or similar for this.
              if (!labelOpts.useHTML) {
                  lines = Math.round(labelHeight / lblMetrics.h);
                  e.pos.y += (
                      // Center the label
                      // TODO: why does this actually center the label?
                      ((lblMetrics.b - (lblMetrics.h - lblMetrics.f)) / 2) +
                      // Adjust for height of additional lines.
                      -(((lines - 1) * lblMetrics.h) / 2)
                  );
              } else {
                  e.pos.y += (
                      // Readjust yCorr in htmlUpdateTransform
                      lblMetrics.b +
                      // Adjust for height of html label
                      -(labelHeight / 2)
                  );
              }
  
              e.pos.x += (axis.horiz && labelOpts.x || 0);
          }
      }
  );
  
  // Draw vertical axis ticks extra long to create cell floors and roofs.
  // Overrides the tickLength for vertical axes.
  addEvent(Axis, 'afterTickSize', function (e) {
      var axis = this,
          dimensions = axis.maxLabelDimensions,
          options = axis.options,
          gridOptions = (options && isObject(options.grid)) ? options.grid : {},
          labelPadding,
          distance;
  
      if (gridOptions.enabled === true) {
          labelPadding = (Math.abs(axis.defaultLeftAxisOptions.labels.x) * 2);
          distance = labelPadding +
              (axis.horiz ? dimensions.height : dimensions.width);
  
          if (isArray(e.tickSize)) {
              e.tickSize[0] = distance;
          } else {
              e.tickSize = [distance];
          }
      }
  });
  
  addEvent(Axis, 'afterGetTitlePosition', function (e) {
      var axis = this,
          options = axis.options,
          gridOptions = (options && isObject(options.grid)) ? options.grid : {};
  
      if (gridOptions.enabled === true) {
          // compute anchor points for each of the title align options
          var title = axis.axisTitle,
              titleWidth = title && title.getBBox().width,
              horiz = axis.horiz,
              axisLeft = axis.left,
              axisTop = axis.top,
              axisWidth = axis.width,
              axisHeight = axis.height,
              axisTitleOptions = options.title,
              opposite = axis.opposite,
              offset = axis.offset,
              tickSize = axis.tickSize() || [0],
              xOption = axisTitleOptions.x || 0,
              yOption = axisTitleOptions.y || 0,
              titleMargin = pick(axisTitleOptions.margin, horiz ? 5 : 10),
              titleFontSize = axis.chart.renderer.fontMetrics(
                  axisTitleOptions.style && axisTitleOptions.style.fontSize,
                  title
              ).f,
              // TODO account for alignment
              // the position in the perpendicular direction of the axis
              offAxis = (horiz ? axisTop + axisHeight : axisLeft) +
                  (horiz ? 1 : -1) * // horizontal axis reverses the margin
                  (opposite ? -1 : 1) * // so does opposite axes
                  (tickSize[0] / 2) +
                  (axis.side === axisSide.bottom ? titleFontSize : 0);
  
          e.titlePosition.x = horiz ?
              axisLeft - titleWidth / 2 - titleMargin + xOption :
              offAxis + (opposite ? axisWidth : 0) + offset + xOption;
          e.titlePosition.y = horiz ?
              (
                  offAxis -
                  (opposite ? axisHeight : 0) +
                  (opposite ? titleFontSize : -titleFontSize) / 2 +
                  offset +
                  yOption
              ) :
              axisTop - titleMargin + yOption;
      }
  });
  
  // Avoid altering tickInterval when reserving space.
  wrap(Axis.prototype, 'unsquish', function (proceed) {
      var axis = this,
          options = axis.options,
          gridOptions = (options && isObject(options.grid)) ? options.grid : {};
  
      if (gridOptions.enabled === true && this.categories) {
          return this.tickInterval;
      }
  
      return proceed.apply(this, argsToArray(arguments));
  });
  
  addEvent(
      Axis,
      'afterSetOptions',
      /**
       * Creates a left and right wall on horizontal axes:
       *
       * - Places leftmost tick at the start of the axis, to create a left wall
       *
       * - Ensures that the rightmost tick is at the end of the axis, to create a
       *   right wall.
       *
       * @private
       * @function
       */
      function (e) {
          var options = this.options,
              userOptions = e.userOptions,
              gridAxisOptions,
              gridOptions = (
                  (options && isObject(options.grid)) ? options.grid : {}
              );
  
          if (gridOptions.enabled === true) {
  
              // Merge the user options into default grid axis options so that
              // when a user option is set, it takes presedence.
              gridAxisOptions = merge(true, {
  
                  className: (
                      'highcharts-grid-axis ' + (userOptions.className || '')
                  ),
  
                  dateTimeLabelFormats: {
                      hour: {
                          list: ['%H:%M', '%H']
                      },
                      day: {
                          list: ['%A, %e. %B', '%a, %e. %b', '%E']
                      },
                      week: {
                          list: ['Week %W', 'W%W']
                      },
                      month: {
                          list: ['%B', '%b', '%o']
                      }
                  },
  
                  grid: {
                      borderWidth: 1
                  },
  
                  labels: {
                      padding: 2,
                      style: {
                          fontSize: '13px'
                      }
                  },
  
                  margin: 0,
  
                  title: {
                      text: null,
                      reserveSpace: false,
                      rotation: 0
                  },
  
                  // In a grid axis, only allow one unit of certain types, for
                  // example we shouln't have one grid cell spanning two days.
                  units: [[
                      'millisecond', // unit name
                      [1, 10, 100]
                  ], [
                      'second',
                      [1, 10]
                  ], [
                      'minute',
                      [1, 5, 15]
                  ], [
                      'hour',
                      [1, 6]
                  ], [
                      'day',
                      [1]
                  ], [
                      'week',
                      [1]
                  ], [
                      'month',
                      [1]
                  ], [
                      'year',
                      null
                  ]]
              }, userOptions);
  
              // X-axis specific options
              if (this.coll === 'xAxis') {
  
                  // For linked axes, tickPixelInterval is used only if the
                  // tickPositioner below doesn't run or returns undefined (like
                  // multiple years)
                  if (
                      defined(userOptions.linkedTo) &&
                      !defined(userOptions.tickPixelInterval)
                  ) {
                      gridAxisOptions.tickPixelInterval = 350;
                  }
  
                  // For the secondary grid axis, use the primary axis' tick
                  // intervals and return ticks one level higher.
                  if (
                      // Check for tick pixel interval in options
                      !defined(userOptions.tickPixelInterval) &&
  
                      // Only for linked axes
                      defined(userOptions.linkedTo) &&
  
                      !defined(userOptions.tickPositioner) &&
                      !defined(userOptions.tickInterval)
                  ) {
                      gridAxisOptions.tickPositioner = function (min, max) {
  
                          var parentInfo = (
                              this.linkedParent &&
                              this.linkedParent.tickPositions &&
                              this.linkedParent.tickPositions.info
                          );
  
                          if (parentInfo) {
  
                              var unitIdx,
                                  count,
                                  unitName,
                                  i,
                                  units = gridAxisOptions.units,
                                  unitRange;
  
                              for (i = 0; i < units.length; i++) {
                                  if (units[i][0] === parentInfo.unitName) {
                                      unitIdx = i;
                                      break;
                                  }
                              }
  
                              // Spanning multiple years, go default
                              if (!units[unitIdx][1]) {
                                  return;
                              }
  
                              // Get the first allowed count on the next unit.
                              if (units[unitIdx + 1]) {
                                  unitName = units[unitIdx + 1][0];
                                  count = (units[unitIdx + 1][1] || [1])[0];
                              }
  
                              unitRange = H.timeUnits[unitName];
                              this.tickInterval = unitRange * count;
                              return this.getTimeTicks(
                                  {
                                      unitRange: unitRange,
                                      count: count,
                                      unitName: unitName
                                  },
                                  min,
                                  max,
                                  this.options.startOfWeek
                              );
                          }
                      };
                  }
  
              }
  
              // Now merge the combined options into the axis options
              merge(true, this.options, gridAxisOptions);
  
              if (this.horiz) {
                  /*               _________________________
                     Make this:    ___|_____|_____|_____|__|
                                   ^                     ^
                                   _________________________
                     Into this:    |_____|_____|_____|_____|
                                      ^                 ^    */
                  options.minPadding = pick(userOptions.minPadding, 0);
                  options.maxPadding = pick(userOptions.maxPadding, 0);
              }
  
              // If borderWidth is set, then use its value for tick and line
              // width.
              if (isNumber(options.grid.borderWidth)) {
                  options.tickWidth = options.lineWidth = gridOptions.borderWidth;
              }
  
          }
      }
  );
  
  addEvent(
      Axis,
      'afterSetAxisTranslation',
      function () {
          var axis = this,
              options = axis.options,
              gridOptions = (
                  (options && isObject(options.grid)) ? options.grid : {}
              ),
              tickInfo = this.tickPositions && this.tickPositions.info,
              userLabels = this.userOptions.labels || {};
  
          if (this.horiz) {
              if (gridOptions.enabled === true) {
                  axis.series.forEach(function (series) {
                      series.options.pointRange = 0;
                  });
              }
  
              // Lower level time ticks, like hours or minutes, represent points
              // in time and not ranges. These should be aligned left in the grid
              // cell by default. The same applies to years of higher order.
              if (
                  tickInfo &&
                  (
                      options.dateTimeLabelFormats[tickInfo.unitName]
                          .range === false ||
                      tickInfo.count > 1 // years
                  ) &&
                  !defined(userLabels.align)
              ) {
                  options.labels.align = 'left';
  
                  if (!defined(userLabels.x)) {
                      options.labels.x = 3;
                  }
              }
          }
      }
  );
  
  // @todo Does this function do what the drawing says? Seems to affect ticks and
  //       not the labels directly?
  addEvent(
      Axis,
      'trimTicks',
      /**
       * Makes tick labels which are usually ignored in a linked axis displayed if
       * they are within range of linkedParent.min.
       * ```
       *                        _____________________________
       *                        |   |       |       |       |
       * Make this:             |   |   2   |   3   |   4   |
       *                        |___|_______|_______|_______|
       *                          ^
       *                        _____________________________
       *                        |   |       |       |       |
       * Into this:             | 1 |   2   |   3   |   4   |
       *                        |___|_______|_______|_______|
       *                          ^
       * ```
       *
       * @private
       */
      function () {
          var axis = this,
              options = axis.options,
              gridOptions = (
                  (options && isObject(options.grid)) ? options.grid : {}
              ),
              categoryAxis = axis.categories,
              tickPositions = axis.tickPositions,
              firstPos = tickPositions[0],
              lastPos = tickPositions[tickPositions.length - 1],
              linkedMin = axis.linkedParent && axis.linkedParent.min,
              linkedMax = axis.linkedParent && axis.linkedParent.max,
              min = linkedMin || axis.min,
              max = linkedMax || axis.max,
              tickInterval = axis.tickInterval,
              moreThanMin = firstPos > min,
              lessThanMax = lastPos < max,
              endMoreThanMin = firstPos < min && firstPos + tickInterval > min,
              startLessThanMax = lastPos > max && lastPos - tickInterval < max;
  
          if (
              gridOptions.enabled === true &&
              !categoryAxis &&
              (axis.horiz || axis.isLinked)
          ) {
              if ((moreThanMin || endMoreThanMin) && !options.startOnTick) {
                  tickPositions[0] = min;
              }
  
              if ((lessThanMax || startLessThanMax) && !options.endOnTick) {
                  tickPositions[tickPositions.length - 1] = max;
              }
          }
      }
  );
  
  addEvent(
      Axis,
      'afterRender',
      /**
       * Draw an extra line on the far side of the outermost axis,
       * creating floor/roof/wall of a grid. And some padding.
       * ```
       * Make this:
       *             (axis.min) __________________________ (axis.max)
       *                           |    |    |    |    |
       * Into this:
       *             (axis.min) __________________________ (axis.max)
       *                        ___|____|____|____|____|__
       * ```
       *
       * @private
       * @function
       *
       * @param {Function} proceed
       *        the original function
       */
      function () {
          var axis = this,
              options = axis.options,
              gridOptions = ((
                  options && isObject(options.grid)) ? options.grid : {}
              ),
              labelPadding,
              distance,
              lineWidth,
              linePath,
              yStartIndex,
              yEndIndex,
              xStartIndex,
              xEndIndex,
              renderer = axis.chart.renderer,
              horiz = axis.horiz,
              axisGroupBox;
  
          if (gridOptions.enabled === true) {
  
              // @todo acutual label padding (top, bottom, left, right)
  
              // Label padding is needed to figure out where to draw the outer
              // line.
              labelPadding = (Math.abs(axis.defaultLeftAxisOptions.labels.x) * 2);
              axis.maxLabelDimensions = axis.getMaxLabelDimensions(
                  axis.ticks,
                  axis.tickPositions
              );
              distance = axis.maxLabelDimensions.width + labelPadding;
              lineWidth = options.lineWidth;
  
              // Remove right wall before rendering if updating
              if (axis.rightWall) {
                  axis.rightWall.destroy();
              }
  
              axisGroupBox = axis.axisGroup.getBBox();
  
              /*
                 Draw an extra axis line on outer axes
                             >
                 Make this:    |______|______|______|___
  
                             > _________________________
                 Into this:    |______|______|______|__|
                                                         */
              if (axis.isOuterAxis() && axis.axisLine) {
                  if (horiz) {
                      // -1 to avoid adding distance each time the chart updates
                      distance = axisGroupBox.height - 1;
                  }
  
                  if (lineWidth) {
                      linePath = axis.getLinePath(lineWidth);
                      xStartIndex = linePath.indexOf('M') + 1;
                      xEndIndex = linePath.indexOf('L') + 1;
                      yStartIndex = linePath.indexOf('M') + 2;
                      yEndIndex = linePath.indexOf('L') + 2;
  
                      // Negate distance if top or left axis
                      if (axis.side === axisSide.top ||
                          axis.side === axisSide.left
                      ) {
                          distance = -distance;
                      }
  
                      // If axis is horizontal, reposition line path vertically
                      if (horiz) {
                          linePath[yStartIndex] = (
                              linePath[yStartIndex] + distance
                          );
                          linePath[yEndIndex] = linePath[yEndIndex] + distance;
                      } else {
                          // If axis is vertical, reposition line path
                          // horizontally
                          linePath[xStartIndex] = (
                              linePath[xStartIndex] + distance
                          );
                          linePath[xEndIndex] = linePath[xEndIndex] + distance;
                      }
  
                      if (!axis.axisLineExtra) {
                          axis.axisLineExtra = renderer.path(linePath)
                              .attr({
                                  
                                  stroke: options.lineColor,
                                  'stroke-width': lineWidth,
                                  
                                  zIndex: 7
                              })
                              .addClass('highcharts-axis-line')
                              .add(axis.axisGroup);
                      } else {
                          axis.axisLineExtra.animate({
                              d: linePath
                          });
                      }
  
                      // show or hide the line depending on options.showEmpty
                      axis.axisLine[axis.showAxis ? 'show' : 'hide'](true);
                  }
              }
  
          }
      }
  );
  
  // Wraps axis init to draw cell walls on vertical axes.
  addEvent(Axis, 'init', function (e) {
      var axis = this,
          chart = axis.chart,
          userOptions = e.userOptions,
          gridOptions = (
              (userOptions && isObject(userOptions.grid)) ?
                  userOptions.grid :
                  {}
          ),
          columnOptions,
          column,
          columnIndex,
          i;
  
      function applyGridOptions() {
          var options = axis.options,
              // TODO: Consider using cell margins defined in % of font size?
              // 25 is optimal height for default fontSize (11px)
              // 25 / 11 ≈ 2.28
              fontSizeToCellHeightRatio = 25 / 11,
              fontSize = options.labels.style.fontSize,
              fontMetrics = axis.chart.renderer.fontMetrics(fontSize);
  
          // Center-align by default
          if (!options.labels) {
              options.labels = {};
          }
          options.labels.align = pick(options.labels.align, 'center');
  
          // @todo: Check against tickLabelPlacement between/on etc
  
          /* Prevents adding the last tick label if the axis is not a category
             axis.
             Since numeric labels are normally placed at starts and ends of a
             range of value, and this module makes the label point at the value,
             an "extra" label would appear. */
          if (!axis.categories) {
              options.showLastLabel = false;
          }
  
          // Make tick marks taller, creating cell walls of a grid. Use cellHeight
          // axis option if set
          if (axis.horiz) {
              options.tickLength = gridOptions.cellHeight ||
                      fontMetrics.h * fontSizeToCellHeightRatio;
          }
  
          // Prevents rotation of labels when squished, as rotating them would not
          // help.
          axis.labelRotation = 0;
          options.labels.rotation = 0;
      }
  
      if (gridOptions.enabled) {
          if (defined(gridOptions.borderColor)) {
              userOptions.tickColor =
                  userOptions.lineColor = gridOptions.borderColor;
          }
  
          // Handle columns, each column is a grid axis
          if (isArray(gridOptions.columns)) {
              columnIndex = 0;
              i = gridOptions.columns.length;
              while (i--) {
                  columnOptions = merge(
                      userOptions,
                      gridOptions.columns[i],
                      {
                          // Force to behave like category axis
                          type: 'category'
                      }
                  );
  
                  delete columnOptions.grid.columns; // Prevent recursion
  
                  column = new Axis(axis.chart, columnOptions);
                  column.isColumn = true;
                  column.columnIndex = columnIndex;
  
                  wrap(column, 'labelFormatter', function (proceed) {
                      var axis = this.axis,
                          tickPos = axis.tickPositions,
                          value = this.value,
                          series = axis.series[0],
                          isFirst = value === tickPos[0],
                          isLast = value === tickPos[tickPos.length - 1],
                          point = H.find(series.options.data, function (p) {
                              return p[axis.isXAxis ? 'x' : 'y'] === value;
                          });
  
                      // Make additional properties available for the formatter
                      this.isFirst = isFirst;
                      this.isLast = isLast;
                      this.point = point;
  
                      // Call original labelFormatter
                      return proceed.call(this);
                  });
  
                  columnIndex++;
              }
              // This axis should not be shown, instead the column axes take over
              addEvent(this, 'afterInit', function () {
                  H.erase(chart.axes, this);
                  H.erase(chart[axis.coll], this);
              });
          } else {
              addEvent(this, 'afterInit', applyGridOptions);
          }
      }
  });
  