From 91f47a4e20d8178dac7b2af9ab240c5424dc5731 Mon Sep 17 00:00:00 2001
From: Matt Pass <matt@mattpass.com>
Date: Wed, 29 Oct 2014 12:43:03 +0000
Subject: [PATCH] Inner line diff highlighting on replaced lines

Loops through all changed lines and marks 3 ranges for pre, on and post
change on those lines
Applies to both main and diff panes
---
 lib/ice-coder.js | 47 +++++++++++++++++++++++++++++++++++++----------
 1 file changed, 37 insertions(+), 10 deletions(-)

diff --git a/lib/ice-coder.js b/lib/ice-coder.js
index dedc3dd..c324deb 100644
--- a/lib/ice-coder.js
+++ b/lib/ice-coder.js
@@ -359,7 +359,7 @@ var ICEcoder = {
 
 	// Update diffs shown to the user in each pane
 	updateDiffs: function() {
-		var cM, cMdiff, mainText, diffText, sm, opcodes, cMmarks, cMdiffMarks, amt, markColor;
+		var cM, cMdiff, mainText, diffText, sm, opcodes, cMmarks, cMdiffMarks, amt, sDiffs;
 
 		// Reset the style array container and main vs diff pane shift difference
 		top.ICEcoder.renderLineStyle = [];
@@ -407,11 +407,17 @@ var ICEcoder = {
 					if (amt > cM.defaultTextHeight()) {
 						top.ICEcoder.renderLineStyle.push(["main", opcodes[i][2], "height", amt + "px"]);
 					}
+					// Mark text in 2 colours, for each line
+					for (var j=0; j<(opcodes[i][2]) - (opcodes[i][1]); j++)  {
+						sDiffs = (top.ICEcoder.findStringDiffs(cM.getLine(opcodes[i][1]+j),cMdiff.getLine(opcodes[i][3]+j)));
+						cM.markText({line: opcodes[i][1]+j, ch: 0}, {line: opcodes[i][3]+j + top.ICEcoder.renderPaneShiftAmount, ch: sDiffs[0]}, {className: "diffGreyLighter"});
+						cM.markText({line: opcodes[i][1]+j, ch: sDiffs[0]}, {line: opcodes[i][3]+j + top.ICEcoder.renderPaneShiftAmount, ch: sDiffs[0]+sDiffs[1]}, {className: "diffGrey"});
+						cM.markText({line: opcodes[i][1]+j, ch: sDiffs[0]+sDiffs[1]}, {line: opcodes[i][3]+j + top.ICEcoder.renderPaneShiftAmount, ch: 1000000}, {className: "diffGreyLighter"});
+					}	
+				// Inserting
+				} else {
+					cM.markText({line: opcodes[i][1], ch: 0}, {line: opcodes[i][2]-1, ch: 1000000}, {className: "diffGreen"});
 				}
-				// Replacing is grey, green in this pane if inserting
-				markColor = opcodes[i][0] == "replace" ? "diffGrey" : "diffGreen";
-				// Mark the range with that class
-				cM.markText({line: opcodes[i][1], ch: 0}, {line: opcodes[i][2]-1, ch: 1000000}, {className: markColor});
 
 				// If inserting or deleting and the main pane hasn't changed, we need to pad out the line in that pane
 				if (opcodes[i][0] != "replace" && opcodes[i][1] == opcodes[i][2]) {
@@ -432,13 +438,18 @@ var ICEcoder = {
 					if (amt > cM.defaultTextHeight()) {
 						top.ICEcoder.renderLineStyle.push(["diff", opcodes[i][4], "height", amt + "px"]);
 					}
+					// Mark text in 2 colours, for each line
+					for (var j=0; j<(opcodes[i][4]) - (opcodes[i][3]); j++)  {
+						sDiffs = (top.ICEcoder.findStringDiffs(cM.getLine(opcodes[i][1]+j),cMdiff.getLine(opcodes[i][3]+j)));
+						cMdiff.markText({line: opcodes[i][1]+j - top.ICEcoder.renderPaneShiftAmount, ch: 0}, {line: opcodes[i][3]+j, ch: sDiffs[0]}, {className: "diffGreyLighter"});
+						cMdiff.markText({line: opcodes[i][1]+j - top.ICEcoder.renderPaneShiftAmount, ch: sDiffs[0]}, {line: opcodes[i][3]+j, ch: sDiffs[0]+sDiffs[2]}, {className: "diffGrey"});
+						cMdiff.markText({line: opcodes[i][1]+j - top.ICEcoder.renderPaneShiftAmount, ch: sDiffs[0]+sDiffs[2]}, {line: opcodes[i][3]+j, ch: 1000000}, {className: "diffGreyLighter"});
+					}
+				// Deleting
+				} else {
+					cMdiff.markText({line: opcodes[i][3], ch: 0}, {line: opcodes[i][4]-1, ch: 1000000}, {className: "diffRed"});
 				}
 
-				// Replacing is grey, red in this pane if deleting
-				markColor = opcodes[i][0] == "replace" ? "diffGrey" : "diffRed";
-				// Mark the range with that class
-				cMdiff.markText({line: opcodes[i][3], ch: 0}, {line: opcodes[i][4]-1, ch: 1000000}, {className: markColor});
-
 				// If inserting or deleting and the diff pane hasn't changed, we need to pad out the line in that pane
 				if (opcodes[i][0] != "replace" && opcodes[i][3] == opcodes[i][4]) {
 					top.ICEcoder.renderLineStyle.push(["diff", opcodes[i][4], "height", ((opcodes[i][2] - opcodes[i][1] + 1) * cM.defaultTextHeight()) + "px"]);
@@ -452,6 +463,22 @@ var ICEcoder = {
 		}	
 	},
 
+	// Find diffs between 2 strings
+	findStringDiffs: function(a, b) {
+		if ("undefined" == typeof a) {a = ""};
+		if ("undefined" == typeof b) {b = ""};
+		for (var c = 0,				// start from the first character
+			d = a.length, e = b.length;	// and from the last characters of both strings
+			a[c] &&				// if not at the end of the string and
+			a[c] == b[c];			// if both strings are equal at this position
+			c++);				// go forward
+		for (; d > c & e > c &			// stop at the position found by the first loop
+			a[d - 1] == b[e - 1];		// if both strings are equal at this position
+			d--) e--;			// go backward
+		return[c, d - c, e - c]			// return position and lengths of the two substrings found
+	},
+
+
 	// Update preview window content
 	updatePreviewWindow: function(thisCM,filepath,filename,fileExt) {
 		if (top.ICEcoder.previewWindow.location.pathname==filepath) {