support merging [WIP]

4 files changed, 68 insertions, 25 deletions

diff --git a/.gitmodules b/.gitmodules
index 417778f..510117d 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -4,3 +4,6 @@
 [submodule "vkBeautify"]
 	path = vkBeautify
 	url = https://github.com/vkiryukhin/vkBeautify
+[submodule "diff-merge"]
+	path = diff-merge
+	url = https://github.com/nighca/diff-merge
diff --git a/github.js b/github.js
index c261cbb..f231e6d 100644
--- a/github.js
+++ b/github.js
@@ -57,7 +57,8 @@ GitHubBackend.prototype.getProject = function (
     userName,
     projectName,
     callBack,
-    errorCall
+    errorCall,
+    commitSha
 ) {
     var myself = this;
 
@@ -67,12 +68,19 @@ GitHubBackend.prototype.getProject = function (
 
     var repo = myself.gh.getRepo(userName, projectName);
     var branch = repo.getBranch(); // master (default)
-
-    branch.read('snap.xml', false).then(
-        function (sourceContent) {
-            callBack.call(
-                null,
-                sourceContent.content
+    branch.getCommits({}).then(
+        function (commits) {
+            branch.read('snap.xml', false).then(
+                function (sourceContent) {
+                    callBack.call(
+                        null,
+                        sourceContent.content,
+                        commits[0].sha
+                    );
+                },
+                function (error) {
+                    errorCall.call(this, error, 'GitHub');
+                }
             );
         },
         function (error) {
@@ -100,7 +108,7 @@ GitHubBackend.prototype.login = function (
         me = myself.gh.getUser();
         if (me !== null) {
             me.getInfo().then(
-                function(info) {
+                function() {
                     myself.username = username;
                     myself.password = password;
 
@@ -121,7 +129,7 @@ GitHubBackend.prototype.login = function (
     }
 };
 
-GitHubBackend.prototype.saveProject = function (commitMessage, ide, callBack, errorCall) {
+GitHubBackend.prototype.saveProject = function (commitMessage, parentCommitSha, lastCommit, ide, callBack, errorCall) {
     var myself = this,
         data;
     var pdata, media;
@@ -162,27 +170,46 @@ GitHubBackend.prototype.saveProject = function (commitMessage, ide, callBack, er
                     }
                 });
 
-                function pushChanges () {
+                pushChanges = function () {
                     if (myself.gh !== null) {
                         var repo = myself.gh.getRepo(myself.username, ide.projectName);
                         var branch = repo.getBranch(); // master (default)
                         var message = commitMessage;
 
-                        var contents = {
-                            'snap.xml': data,
-                            'README.md': ide.projectNotes
+                        writeChanges = function (code, pcSha) {
+                            if (pcSha !== parentCommitSha && data !== code) {
+                                var compareResult = window.diff.compare(lastCommit, data, '\n'); // get diff from last push
+                                data = window.diff.merge(code, compareResult); // apply it to the latest code
+                                console.log(data);
+                            }
+
+                            var contents = {
+                                'snap.xml': data,
+                                'README.md': ide.projectNotes
+                            };
+
+                            branch.writeMany(contents, message, pcSha).then(
+                                function () {
+                                    callBack.call();
+                                },
+                                function (error) {
+                                    errorCall.call(this, error, 'GitHub');
+                                }
+                            );
                         };
 
-                        branch.writeMany(contents, message).then(
-                            function () {
-                                callBack.call();
-                            },
-                            function (error) {
-                                errorCall.call(this, error, 'GitHub');
-                            }
-                        );
+                        if (parentCommitSha !== null) { // repo was just created
+                            myself.getProject(myself.username, ide.projectName,
+                                writeChanges,
+                                function (error) {
+                                    errorCall.call(this, error, 'GitHub');
+                                }
+                            );
+                        } else {
+                            writeChanges(data, parentCommitSha);
+                        }
                     }
-                }
+                };
 
                 if (exists === false){
                     myself.gh.getUser().createRepo(repoName, { // these should be discussed
diff --git a/gui.js b/gui.js
index 6ae7222..1cc8468 100644
--- a/gui.js
+++ b/gui.js
@@ -221,6 +221,8 @@ IDE_Morph.prototype.init = function (isAutoFill) {
     this.stageRatio = 1; // for IDE animations, e.g. when zooming
 
     this.loadNewProject = false; // flag when starting up translated
+    this.parentCommitSha = null; // for GitHub
+    this.lastCommit = null; // for GitHub
     this.shield = null;
 
     // initialize inherited properties:
@@ -401,13 +403,15 @@ IDE_Morph.prototype.openIn = function (world) {
             GitHub.getProject(
                 dict.Username,
                 dict.projectName,
-                function (code) {
+                function (code, pcSha) {
                     var msg;
                     myself.nextSteps([
                         function () {
                             msg = myself.showMessage('Opening GitHub project...');
                         },
                         function () {
+                            myself.parentCommitSha = pcSha;
+                            myself.lastCommit = code;
                             myself.rawOpenCloudDataString(code);
                             myself.hasChangedMedia = true;
                         },
@@ -3935,13 +3939,17 @@ IDE_Morph.prototype.saveProjectToGitHub = function (name, commitMessage) {
         this.setProjectName(name);
         GitHub.saveProject(
             commitMessage,
+            this.parentCommitSha,
+            this.lastCommit,
             this,
             function () {
                 GitHub.getProject(
                     GitHub.username,
                     name, 
-                    function (code) {
+                    function (code, pcSha) {
                         myself.source = 'github';
+                        myself.parentCommitSha = pcSha;
+                        myself.lastCommit = code;
                         myself.droppedText(code);
                     },
                     myself.githubError()
@@ -5072,8 +5080,10 @@ ProjectDialogMorph.prototype.rawOpenGitHubProject = function (proj, user) {
     GitHub.getProject(
         user,
         proj.ProjectName, 
-        function (code) {
+        function (code, pcSha) {
             myself.ide.source = 'github';
+            myself.ide.parentCommitSha = pcSha;
+            myself.ide.lastCommit = code;
             myself.ide.droppedText(code);
         },
         myself.ide.githubError()
@@ -5171,6 +5181,8 @@ ProjectDialogMorph.prototype.saveGitHubProject = function () {
     this.ide.showMessage('Committing project\nto GitHub...');
     GitHub.saveProject(
         null,
+        this.ide.parentCommitSha,
+        this.ide.lastCommit,
         this.ide,
         function () {
             myself.ide.source = 'github';
diff --git a/snap.html b/snap.html
index 733b571..63bdebd 100755
--- a/snap.html
+++ b/snap.html
@@ -22,6 +22,7 @@
                 <script type="text/javascript" src="github.js"></script>
 		<script type="text/javascript" src="sha512.js"></script>
                 <script type="text/javascript" src="vkBeautify/vkbeautify.js"></script>
+                <script type="text/javascript" src="diff-merge/dist/diff.js"></script>
 		<script type="text/javascript">
 			var world;
 			window.onload = function () {