From 1318e8703259a6ed32f13be003db4124e61429ef Mon Sep 17 00:00:00 2001
From: friebetill <friebetill@gmail.com>
Date: Sat, 28 Jan 2023 18:20:40 +0800
Subject: [PATCH] Get difference between the two files

---
 package.json |  8 +++++++-
 src/main.ts  | 24 +++++++++++++++++++++---
 yarn.lock    | 10 ++++++++++
 3 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/package.json b/package.json
index be2112a..f6076e1 100644
--- a/package.json
+++ b/package.json
@@ -10,11 +10,17 @@
 		"coverage": "vitest run --coverage",
 		"release": "./scripts/release.sh"
 	},
-	"keywords": ["obsidian"],
+	"keywords": [
+		"obsidian"
+	],
 	"author": "Till Friebe",
 	"authorUrl": "https://friebetill.github.io/",
 	"license": "MIT",
+	"dependencies": {
+		"diff": "^5.1.0"
+	},
 	"devDependencies": {
+		"@types/diff": "^5.0.2",
 		"@types/node": "^16.11.6",
 		"@typescript-eslint/eslint-plugin": "5.29.0",
 		"@typescript-eslint/parser": "5.29.0",
diff --git a/src/main.ts b/src/main.ts
index cf2608c..bee302e 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -1,4 +1,6 @@
 import { Editor, Plugin, TFile } from "obsidian";
+
+import { createTwoFilesPatch } from "diff";
 import { SelectFileModal } from "./select_file_modal";
 
 export default class FileDiffPlugin extends Plugin {
@@ -15,12 +17,28 @@ export default class FileDiffPlugin extends Plugin {
 				const selectableFiles = this.app.vault.getFiles();
 				selectableFiles.remove(activeFile);
 
-				await this.showSelectOtherFileModal({
+				const fileToCompare = await this.showSelectOtherFileModal({
 					selectableFiles: selectableFiles,
 				});
+				if (fileToCompare == null) {
+					return;
+				}
 
-				// Install library to calculate the difference between two files
-				// Open new file where the differences are shown
+				const activeFileContent = await this.app.vault.read(activeFile);
+				const fileToCompareContent = await this.app.vault.read(
+					fileToCompare
+				);
+
+				const patch = createTwoFilesPatch(
+					activeFile.path,
+					fileToCompare.path,
+					activeFileContent,
+					fileToCompareContent
+				);
+
+				console.log(patch);
+
+				// Open viewer to show patch
 			},
 		});
 	}
diff --git a/yarn.lock b/yarn.lock
index 23cd943..4117edc 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -140,6 +140,11 @@
   dependencies:
     "@types/tern" "*"
 
+"@types/diff@^5.0.2":
+  version "5.0.2"
+  resolved "https://registry.yarnpkg.com/@types/diff/-/diff-5.0.2.tgz#dd565e0086ccf8bc6522c6ebafd8a3125c91c12b"
+  integrity sha512-uw8eYMIReOwstQ0QKF0sICefSy8cNO/v7gOTiIy9SbwuHyEecJUm7qlgueOO5S1udZ5I/irVydHVwMchgzbKTg==
+
 "@types/estree@*":
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/@types/estree/-/estree-1.0.0.tgz#5fb2e536c1ae9bf35366eed879e827fa59ca41c2"
@@ -266,6 +271,11 @@ debug@^4.3.4:
   dependencies:
     ms "2.1.2"
 
+diff@^5.1.0:
+  version "5.1.0"
+  resolved "https://registry.yarnpkg.com/diff/-/diff-5.1.0.tgz#bc52d298c5ea8df9194800224445ed43ffc87e40"
+  integrity sha512-D+mk+qE8VC/PAUrlAU34N+VfXev0ghe5ywmpqrawphmVZc1bEfn56uo9qpyGp1p4xpzOHkSW4ztBd6L7Xx4ACw==
+
 dir-glob@^3.0.1:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/dir-glob/-/dir-glob-3.0.1.tgz#56dbf73d992a4a93ba1584f4534063fd2e41717f"