From 4a3a9f1a214d2729f9ff409c68ace6224281ed73 Mon Sep 17 00:00:00 2001
From: Evert Timberg <evert.timberg@gmail.com>
Date: Sat, 6 Jun 2015 09:27:03 -0400
Subject: [PATCH] Change the scale fitting code from 2 pass fit to a 2.5 pass
 fit. The fit function is now passed a margin object that contains the margins
 on the left, top, right, and bottom of the scale. This is useful to know if
 you can draw outside of the width. This is used by the dataset scale so that
 extra padding is only added for long labels if absolutely required. If there
 is unused space underneath the vertical axes, that space is used first.

---
 src/Chart.Scale.js | 89 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 74 insertions(+), 15 deletions(-)

diff --git a/src/Chart.Scale.js b/src/Chart.Scale.js
index 9a99e9127..d42fe9c69 100644
--- a/src/Chart.Scale.js
+++ b/src/Chart.Scale.js
@@ -176,30 +176,81 @@
                         return wrapper.scale === scaleInstance;
                     });
 
+                    var scaleMargin = {
+                        left: totalLeftWidth,
+                        right: totalRightWidth,
+                        top: 0,
+                        bottom: 0,
+                    };
+
                     if (wrapper) {
-                        scaleInstance.fit(maxChartWidth, wrapper.minSize.width);
+                        scaleInstance.fit(maxChartWidth, wrapper.minSize.height, scaleMargin);
                     }
                 };
 
+                var totalLeftWidth = xPadding;
+                var totalRightWidth = xPadding;
+                var totalTopHeight = yPadding;
+                var totalBottomHeight = yPadding;
+
                 helpers.each(leftScales, verticalScaleFitFunction);
                 helpers.each(rightScales, verticalScaleFitFunction);
-                helpers.each(topScales, horizontalScaleFitFunction);
-                helpers.each(bottomScales, horizontalScaleFitFunction);
 
-                // Step 7 
-                var totalLeftWidth = xPadding;
-                var totalTopHeight = yPadding;
-
-                // Calculate total width of all left axes
+                // Figure out how much margin is on the left and right of the horizontal axes
                 helpers.each(leftScales, function(scaleInstance) {
                     totalLeftWidth += scaleInstance.width;
                 });
 
-                // Calculate total height of all top axes
+                helpers.each(rightScales, function(scaleInstance) {
+                    totalRightWidth += scaleInstance.width;
+                });
+
+                helpers.each(topScales, horizontalScaleFitFunction);
+                helpers.each(bottomScales, horizontalScaleFitFunction);
+
                 helpers.each(topScales, function(scaleInstance) {
                     totalTopHeight += scaleInstance.height;
                 });
+                helpers.each(bottomScales, function(scaleInstance) {
+                    totalBottomHeight += scaleInstance.height;
+                });
 
+                // Let the left scale know the final margin
+                helpers.each(leftScales, function(scaleInstance) {
+                    var wrapper = helpers.findNextWhere(minimumScaleSizes, function(wrapper) {
+                        return wrapper.scale === scaleInstance;
+                    });
+
+                    var scaleMargin = {
+                        left: 0,
+                        right: 0,
+                        top: totalTopHeight,
+                        bottom: totalBottomHeight
+                    };
+
+                    if (wrapper) {
+                        scaleInstance.fit(wrapper.minSize.width, maxChartHeight, scaleMargin);
+                    }
+                });
+
+                helpers.each(rightScales, function(scaleInstance) {
+                    var wrapper = helpers.findNextWhere(minimumScaleSizes, function(wrapper) {
+                        return wrapper.scale === scaleInstance;
+                    });
+
+                    var scaleMargin = {
+                        left: 0,
+                        right: 0,
+                        top: totalTopHeight,
+                        bottom: totalBottomHeight
+                    };
+
+                    if (wrapper) {
+                        scaleInstance.fit(wrapper.minSize.width, maxChartHeight, scaleMargin);
+                    }
+                });
+
+                // Step 7 
                 // Position the scales
                 var left = xPadding;
                 var top = yPadding;
@@ -592,7 +643,7 @@
                         } else {
                             // right side
                             labelStartX = this.left + 5;
-                            this.ctx.textAlign = "left"
+                            this.ctx.textAlign = "left";
                         }
 
                         this.ctx.textBaseline = "middle";
@@ -633,7 +684,7 @@
                 return this.top + (index * (this.height / this.max));
             }
         },
-        calculateLabelRotation: function(maxHeight) {
+        calculateLabelRotation: function(maxHeight, margins) {
             //Get the width of each grid by calculating the difference
             //between x offsets between 0 and 1.
             var labelFont = helpers.fontString(this.options.labels.fontSize, this.options.labels.fontStyle, this.options.labels.fontFamily);
@@ -688,8 +739,16 @@
                 }
             } else {
                 this.labelWidth = 0;
-                this.paddingRight = this.padding;
-                this.paddingLeft = this.padding;
+                this.paddingRight = 0;
+                this.paddingLeft = 0;
+            }
+
+            if (margins) {
+                this.paddingLeft -= margins.left;
+                this.paddingRight -= margins.right;
+
+                this.paddingLeft = Math.max(this.paddingLeft, 0);
+                this.paddingRight = Math.max(this.paddingRight, 0);
             }
 
         },
@@ -697,9 +756,9 @@
         // @param {number} maxWidth : the max width the axis can be
         // @param {number} maxHeight: the max height the axis can be
         // @return {object} minSize : the minimum size needed to draw the axis
-        fit: function(maxWidth, maxHeight) {
+        fit: function(maxWidth, maxHeight, margins) {
             this.calculateRange();
-            this.calculateLabelRotation();
+            this.calculateLabelRotation(maxHeight, margins);
 
             var minSize = {
                 width: 0,