From ec959ebbed53df2e4aaf3d971ee33b1c5e1b943c Mon Sep 17 00:00:00 2001
From: Vishesh Handa <me@vhanda.in>
Date: Mon, 27 Jan 2020 23:28:13 +0100
Subject: [PATCH] Add a helper file to resolve merge conflicts

I'm not sure how to integrate this into our merging code.
---
 lib/utils/merge_conflict_resolver.dart | 36 ++++++++++++++++++++++++++
 test/merge_conflcts_resolver_test.dart | 35 +++++++++++++++++++++++++
 2 files changed, 71 insertions(+)
 create mode 100644 lib/utils/merge_conflict_resolver.dart
 create mode 100644 test/merge_conflcts_resolver_test.dart

diff --git a/lib/utils/merge_conflict_resolver.dart b/lib/utils/merge_conflict_resolver.dart
new file mode 100644
index 00000000..6976b269
--- /dev/null
+++ b/lib/utils/merge_conflict_resolver.dart
@@ -0,0 +1,36 @@
+import 'dart:convert';
+
+String resolveMergeConflict(String fileContents) {
+  var lines = const LineSplitter().convert(fileContents);
+  var newLines = <String>[];
+
+  var inMergeConflict = false;
+  var seenStartMarker = false;
+  var seenMiddleMarker = false;
+
+  lines.forEach((line) {
+    if (line.startsWith("<<<<<<<") && !inMergeConflict) {
+      inMergeConflict = true;
+      seenStartMarker = true;
+      return;
+    }
+    if (line == "=======" && inMergeConflict && seenStartMarker) {
+      seenMiddleMarker = true;
+      return;
+    }
+    if (line.startsWith(">>>>>>>") && inMergeConflict && seenMiddleMarker) {
+      inMergeConflict = false;
+      seenStartMarker = false;
+      seenMiddleMarker = false;
+      return;
+    }
+
+    if (inMergeConflict && seenMiddleMarker) {
+      return;
+    }
+
+    newLines.add(line);
+  });
+
+  return newLines.join('\n');
+}
diff --git a/test/merge_conflcts_resolver_test.dart b/test/merge_conflcts_resolver_test.dart
new file mode 100644
index 00000000..5fae17ef
--- /dev/null
+++ b/test/merge_conflcts_resolver_test.dart
@@ -0,0 +1,35 @@
+import 'package:test/test.dart';
+import 'package:gitjournal/utils/merge_conflict_resolver.dart';
+
+void main() {
+  test("Body only conflict", () {
+    String input = '''---
+title: Foo
+---
+
+<<<<<<< HEAD
+This is the body in GitJournal
+=======
+This is the body from the remote/origin
+>>>>>>> remote/origin
+
+Some more text.''';
+
+    String expectedOutput = '''---
+title: Foo
+---
+
+This is the body in GitJournal
+
+Some more text.''';
+
+    expect(resolveMergeConflict(input), equals(expectedOutput));
+  });
+
+  /*
+  test("YAML Conflict", () {});
+  test("YAML Conflict from 1st line", () {});
+  test("YAML Conflict different modified", () {});
+  test("YAML and body conflict", () {});
+  */
+}