From dcf33df1a60d615e6c896e2952a49c6cf1c25a4f Mon Sep 17 00:00:00 2001
From: Richie Bendall <richiebendall@gmail.com>
Date: Sat, 21 Nov 2020 04:44:47 +1300
Subject: [PATCH] Add browser support (#36)

Co-authored-by: Sindre Sorhus <sindresorhus@gmail.com>
---
 browser.js   | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 package.json | 14 ++++++++---
 readme.md    |  2 +-
 3 files changed, 80 insertions(+), 4 deletions(-)
 create mode 100644 browser.js

diff --git a/browser.js b/browser.js
new file mode 100644
index 0000000..0befb48
--- /dev/null
+++ b/browser.js
@@ -0,0 +1,68 @@
+/* eslint-env browser */
+'use strict';
+import pEvent from 'p-event';
+import isIp from 'is-ip';
+
+const getIp = async ({isSecondTry = false} = {}) => {
+	try {
+		const peerConnection = new RTCPeerConnection({iceServers: []});
+
+		peerConnection.createDataChannel('');
+		peerConnection.createOffer(peerConnection.setLocalDescription.bind(peerConnection), () => {});
+
+		const {candidate} = await pEvent(peerConnection, 'icecandidate', {
+			timeout: 10000
+		});
+
+		peerConnection.close();
+
+		if (candidate && candidate.candidate) {
+			const result = candidate.candidate.split(' ')[4];
+			if (result.endsWith('.local')) {
+				if (isSecondTry) {
+					return;
+				}
+
+				const inputDevices = await navigator.mediaDevices.enumerateDevices();
+				const inputDeviceTypes = new Set(inputDevices.map(({kind}) => kind));
+
+				const constraints = {};
+
+				if (inputDeviceTypes.has('audioinput')) {
+					constraints.audio = true;
+				} else if (inputDeviceTypes.has('videoinput')) {
+					constraints.video = true;
+				} else {
+					return;
+				}
+
+				const mediaStream = await navigator.mediaDevices.getUserMedia(constraints);
+				for (const track of mediaStream.getTracks()) {
+					track.stop();
+				}
+
+				return await getIp({isSecondTry: true});
+			}
+
+			return result;
+		}
+	} catch {}
+};
+
+export const v4 = async () => {
+	const result = await getIp();
+	if (isIp.v4(result)) {
+		return result;
+	}
+};
+
+v4.sync = () => undefined;
+
+export const v6 = async () => {
+	const result = await getIp();
+	if (isIp.v6(result)) {
+		return result;
+	}
+};
+
+v6.sync = () => undefined;
diff --git a/package.json b/package.json
index bff021a..0c1aadb 100644
--- a/package.json
+++ b/package.json
@@ -18,8 +18,13 @@
 	},
 	"files": [
 		"index.js",
-		"index.d.ts"
+		"index.d.ts",
+		"browser.js"
 	],
+	"exports": {
+		"browser": "./browser.js",
+		"default": "./index.js"
+	},
 	"keywords": [
 		"ip",
 		"ipv6",
@@ -34,11 +39,14 @@
 	],
 	"dependencies": {
 		"default-gateway": "^6.0.0",
-		"ipaddr.js": "^1.9.1"
+		"ipaddr.js": "^1.9.1",
+		"is-ip": "^3.1.0",
+		"p-event": "^4.2.0"
 	},
 	"devDependencies": {
 		"ava": "^2.4.0",
 		"tsd": "^0.13.1",
 		"xo": "^0.32.1"
-	}
+	},
+	"browser": "browser.js"
 }
diff --git a/readme.md b/readme.md
index 6214456..930fe32 100644
--- a/readme.md
+++ b/readme.md
@@ -30,7 +30,7 @@ console.log(internalIp.v4.sync())
 
 The module returns the address of the internet-facing interface, as determined from the default gateway. When the address cannot be determined for any reason, `undefined` will be returned.
 
-The module relies on operating systems tools. On Linux and Android, the `ip` command must be available, which depending on distribution might not be installed by default. It is usually provided by the `iproute2` package.
+The module relies on operating systems tools. On Linux and Android, the `ip` command must be available, which depending on distribution might not be installed by default. It is usually provided by the `iproute2` package. `.v4.sync()` and `.v6.sync()` are not supported in browsers and just return `undefined`.
 
 ## Related