From ad211b4b4ec257f1e6376faa2d04209b5129e301 Mon Sep 17 00:00:00 2001
From: Laurent Cozic <laurent@cozic.net>
Date: Wed, 12 Jun 2019 09:45:31 +0100
Subject: [PATCH] Clipper: Fixes #1600: Handle SVG images and fix issue with
 invalid file extensions

---
 ReactNativeClient/lib/net-utils.js         |  7 +++++++
 ReactNativeClient/lib/path-utils.js        |  5 +++--
 ReactNativeClient/lib/services/rest/Api.js | 20 +++++++++++++++++++-
 3 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/ReactNativeClient/lib/net-utils.js b/ReactNativeClient/lib/net-utils.js
index e1f62d52b..ca14e95ca 100644
--- a/ReactNativeClient/lib/net-utils.js
+++ b/ReactNativeClient/lib/net-utils.js
@@ -30,4 +30,11 @@ netUtils.findAvailablePort = async (possiblePorts, extraRandomPortsToTry = 20) =
 	return port;
 }
 
+netUtils.mimeTypeFromHeaders = headers => {
+	if (!headers || !headers['content-type']) return null;
+
+	const splitted = headers['content-type'].split(';');
+	return splitted[0].trim().toLowerCase();
+}
+
 module.exports = { netUtils };
\ No newline at end of file
diff --git a/ReactNativeClient/lib/path-utils.js b/ReactNativeClient/lib/path-utils.js
index df2917d23..4d4a1d8f1 100644
--- a/ReactNativeClient/lib/path-utils.js
+++ b/ReactNativeClient/lib/path-utils.js
@@ -37,9 +37,10 @@ function isHidden(path) {
 	return b[0] === '.';
 }
 
-function safeFileExtension(e) {
+function safeFileExtension(e, maxLength = null) {
+	if (maxLength === null) maxLength = 8;
 	if (!e || !e.replace) return '';
-	return e.replace(/[^a-zA-Z0-9]/g, '')
+	return e.replace(/[^a-zA-Z0-9]/g, '').substr(0, maxLength);
 }
 
 function safeFilename(e, maxLength = null, allowSpaces = false) {
diff --git a/ReactNativeClient/lib/services/rest/Api.js b/ReactNativeClient/lib/services/rest/Api.js
index bd971d19c..4c0ebd6a3 100644
--- a/ReactNativeClient/lib/services/rest/Api.js
+++ b/ReactNativeClient/lib/services/rest/Api.js
@@ -12,6 +12,7 @@ const md5 = require('md5');
 const { shim } = require('lib/shim');
 const HtmlToMd = require('lib/HtmlToMd');
 const urlUtils = require('lib/urlUtils.js');
+const { netUtils } = require('lib/net-utils');
 const { fileExtension, safeFileExtension, safeFilename, filename } = require('lib/path-utils');
 const ApiResponse = require('lib/services/rest/ApiResponse');
 const SearchEngineUtils = require('lib/services/SearchEngineUtils');
@@ -459,6 +460,18 @@ class Api {
 		return await shim.attachFileToNote(note, tempFilePath);
 	}
 
+	async tryToGuessImageExtFromMimeType_(response, imagePath) {
+		const mimeType = netUtils.mimeTypeFromHeaders(response.headers);
+		if (!mimeType) return imagePath;
+
+		const newExt = mimeUtils.toFileExtension(mimeType);
+		if (!newExt) return imagePath;
+
+		const newImagePath = imagePath + '.' + newExt;
+		await shim.fsDriver().move(imagePath, newImagePath);
+		return newImagePath;
+	}
+
 	async downloadImage_(url, allowFileProtocolImages) {
 		const tempDir = Setting.value('tempDir');
 
@@ -466,6 +479,7 @@ class Api {
 
 		const name = isDataUrl ? md5(Math.random() + '_' + Date.now()) : filename(url);
 		let fileExt = isDataUrl ? mimeUtils.toFileExtension(mimeUtils.fromDataUrl(url)) : safeFileExtension(fileExtension(url).toLowerCase());
+		if (!mimeUtils.fromFileExtension(fileExt)) fileExt = ''; // If the file extension is unknown - clear it.
 		if (fileExt) fileExt = '.' + fileExt;
 		let imagePath = tempDir + '/' + safeFilename(name) + fileExt;
 		if (await shim.fsDriver().exists(imagePath)) imagePath = tempDir + '/' + safeFilename(name) + '_' + md5(Math.random() + '_' + Date.now()).substr(0,10) + fileExt;
@@ -479,7 +493,11 @@ class Api {
 				const localPath = uri2path(url);
 				await shim.fsDriver().copy(localPath, imagePath);
 			} else {
-				await shim.fetchBlob(url, { path: imagePath });
+				const response = await shim.fetchBlob(url, { path: imagePath, maxRetry: 1 });
+
+				// If we could not find the file extension from the URL, try to get it
+				// now based on the Content-Type header.
+				if (!fileExt) imagePath = this.tryToGuessImageExtFromMimeType_(response, imagePath);
 			}
 			return imagePath;
 		} catch (error) {