Fixes the distance issue between the legend and the horizontal bar ch…

…art (Fixes ChartsOrg#2138) (ChartsOrg#2214)

* Fixes the distance issue between the legend and the horizontal bar chart (Fixes ChartsOrg#2138)

Override the function calculateLegendOffsets in HorizontalBarChartView
in order to select the correct axis for distance calculation. In case
of horizontal chart the x-axis is described the the rightAxis (bottom)
or the leftAxis(top).

* Added guard for _legend status

Source/Charts/Charts/HorizontalBarChartView.swift

@@ -34,6 +34,67 @@ open class HorizontalBarChartView: BarChartView
         self.highlighter = HorizontalBarHighlighter(chart: self)
     }
 
+    internal override func calculateLegendOffsets(offsetLeft: inout CGFloat, offsetTop: inout CGFloat, offsetRight: inout CGFloat, offsetBottom: inout CGFloat)
+    {
+        guard
+            let legend = _legend,
+            legend.isEnabled,
+            legend.drawInside
+        else { return }
+
+        // setup offsets for legend
+        switch legend.orientation
+        {
+        case .vertical:
+            switch legend.horizontalAlignment
+            {
+            case .left:
+                offsetLeft += min(legend.neededWidth, _viewPortHandler.chartWidth * legend.maxSizePercent) + legend.xOffset
+
+            case .right:
+                offsetRight += min(legend.neededWidth, _viewPortHandler.chartWidth * legend.maxSizePercent) + legend.xOffset
+
+            case .center:
+
+                switch legend.verticalAlignment
+                {
+                case .top:
+                    offsetTop += min(legend.neededHeight, _viewPortHandler.chartHeight * legend.maxSizePercent) + legend.yOffset
+
+                case .bottom:
+                    offsetBottom += min(legend.neededHeight, _viewPortHandler.chartHeight * legend.maxSizePercent) + legend.yOffset
+
+                default:
+                    break
+                }
+            }
+
+        case .horizontal:
+            switch legend.verticalAlignment
+            {
+            case .top:
+                offsetTop += min(legend.neededHeight, _viewPortHandler.chartHeight * legend.maxSizePercent) + legend.yOffset
+
+                // left axis equals the top x-axis in a horizontal chart
+                if leftAxis.isEnabled && leftAxis.isDrawLabelsEnabled
+                {
+                    offsetTop += leftAxis.getRequiredHeightSpace()
+                }
+
+            case .bottom:
+                offsetBottom += min(legend.neededHeight, _viewPortHandler.chartHeight * legend.maxSizePercent) + legend.yOffset
+
+                // right axis equals the bottom x-axis in a horizontal chart
+                if rightAxis.isEnabled && rightAxis.isDrawLabelsEnabled
+                {
+                    offsetBottom += rightAxis.getRequiredHeightSpace()
+                }
+            default:
+                break
+            }
+        }
+    }
+
     internal override func calculateOffsets()
     {
         var offsetLeft: CGFloat = 0.0,