From 18ef4472cd67087d1e707c0c68eef6bee2a50390 Mon Sep 17 00:00:00 2001
From: Ian Storm Taylor <ian@ianstormtaylor.com>
Date: Sat, 3 Dec 2016 23:49:50 -0800
Subject: [PATCH] refactor environment detection, remove unused deps

---
 package.json                 |  4 +-
 src/constants/environment.js | 92 ++++++++++++++++++++++++++----------
 2 files changed, 69 insertions(+), 27 deletions(-)

diff --git a/package.json b/package.json
index bb8fa21ac..8cb709d1d 100644
--- a/package.json
+++ b/package.json
@@ -8,7 +8,6 @@
   "dependencies": {
     "cheerio": "^0.22.0",
     "debug": "^2.3.2",
-    "detect-browser": "^1.3.3",
     "direction": "^0.1.5",
     "es6-map": "^0.1.4",
     "esrever": "^0.2.0",
@@ -16,8 +15,7 @@
     "immutable": "^3.8.1",
     "is-empty": "^1.0.0",
     "keycode": "^2.1.2",
-    "type-of": "^2.0.1",
-    "ua-parser-js": "^0.7.10"
+    "type-of": "^2.0.1"
   },
   "peerDependencies": {
     "react": "^0.14.0 || ^15.0.0",
diff --git a/src/constants/environment.js b/src/constants/environment.js
index d0d7551f1..86d88f28f 100644
--- a/src/constants/environment.js
+++ b/src/constants/environment.js
@@ -1,6 +1,67 @@
 
-import Parser from 'ua-parser-js'
-import browser from 'detect-browser'
+/**
+ * Browser matching rules.
+ *
+ * @type {Array}
+ */
+
+const BROWSER_RULES = [
+  ['edge', /Edge\/([0-9\._]+)/],
+  ['chrome', /(?!Chrom.*OPR)Chrom(?:e|ium)\/([0-9\.]+)(:?\s|$)/],
+  ['firefox', /Firefox\/([0-9\.]+)(?:\s|$)/],
+  ['opera', /Opera\/([0-9\.]+)(?:\s|$)/],
+  ['opera', /OPR\/([0-9\.]+)(:?\s|$)$/],
+  ['ie', /Trident\/7\.0.*rv\:([0-9\.]+)\).*Gecko$/],
+  ['ie', /MSIE\s([0-9\.]+);.*Trident\/[4-7].0/],
+  ['ie', /MSIE\s(7\.0)/],
+  ['android', /Android\s([0-9\.]+)/],
+  ['safari', /Version\/([0-9\._]+).*Safari/],
+]
+
+/**
+ * Operating system matching rules.
+ *
+ * @type {Array}
+ */
+
+const OS_RULES = [
+  ['macos', /mac os x/i],
+  ['ios', /os ([\.\_\d]+) like mac os/i],
+  ['android', /android/i],
+  ['firefoxos', /mozilla\/[a-z\.\_\d]+ \((?:mobile)|(?:tablet)/i],
+  ['windows', /windows\s*(?:nt)?\s*([\.\_\d]+)/i],
+]
+
+/**
+ * Define variables to store the result.
+ */
+
+let BROWSER
+let OS
+
+/**
+ * Run the matchers when in browser.
+ */
+
+if (process.browser) {
+  const { userAgent } = window.navigator
+
+  for (const rule of BROWSER_RULES) {
+    const [ name, regexp ] = rule
+    if (regexp.test(userAgent)) {
+      BROWSER = name
+      break
+    }
+  }
+
+  for (const rule of OS_RULES) {
+    const [ name, regexp ] = rule
+    if (regexp.test(userAgent)) {
+      OS = name
+      break
+    }
+  }
+}
 
 /**
  * Export.
@@ -8,26 +69,9 @@ import browser from 'detect-browser'
  * @type {Object}
  */
 
-export const IS_ANDROID = process.browser && browser.name == 'android'
-export const IS_CHROME = process.browser && browser.name == 'chrome'
-export const IS_EDGE = process.browser && browser.name == 'edge'
-export const IS_FIREFOX = process.browser && browser.name == 'firefox'
-export const IS_IE = process.browser && browser.name == 'ie'
-export const IS_IOS = process.browser && browser.name == 'ios'
-export const IS_MAC = process.browser && new Parser().getOS().name == 'Mac OS'
-export const IS_SAFARI = process.browser && browser.name == 'safari'
-export const IS_UBUNTU = process.browser && new Parser().getOS().name == 'Ubuntu'
-export const IS_WINDOWS = process.browser && /Windows/.test(new Parser().getOS().name)
+export const IS_CHROME = BROWSER === 'chrome'
+export const IS_FIREFOX = BROWSER === 'firefox'
+export const IS_SAFARI = BROWSER === 'safari'
 
-export default {
-  IS_ANDROID,
-  IS_CHROME,
-  IS_EDGE,
-  IS_FIREFOX,
-  IS_IE,
-  IS_IOS,
-  IS_MAC,
-  IS_SAFARI,
-  IS_UBUNTU,
-  IS_WINDOWS
-}
+export const IS_MAC = OS === 'macos'
+export const IS_WINDOWS = OS === 'windows'