From 560ec06eeb6f7e771679dbdf7907cad0869fa9ce Mon Sep 17 00:00:00 2001
From: Denis Demchenko <lancedikson@gmail.com>
Date: Mon, 2 Jul 2018 16:51:40 +0300
Subject: [PATCH] Add Parser.check and related things

---
 package-lock.json |  3 +--
 package.json      |  5 ++++-
 src/parser.js     | 42 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index b9f77fa..0d14541 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -15666,8 +15666,7 @@
     "semver": {
       "version": "5.5.0",
       "resolved": "https://registry.npmjs.org/semver/-/semver-5.5.0.tgz",
-      "integrity": "sha512-4SJ3dm0WAwWy/NVeioZh5AntkdJoWKxHxcmyP622fOkgHa4z3R0TdBJICINyaSDE6uNwVc8gZr+ZinwZAH4xIA==",
-      "dev": true
+      "integrity": "sha512-4SJ3dm0WAwWy/NVeioZh5AntkdJoWKxHxcmyP622fOkgHa4z3R0TdBJICINyaSDE6uNwVc8gZr+ZinwZAH4xIA=="
     },
     "semver-diff": {
       "version": "2.1.0",
diff --git a/package.json b/package.json
index 40897d1..b31f5af 100644
--- a/package.json
+++ b/package.json
@@ -60,5 +60,8 @@
     "test": "eslint ./src & nyc --reporter=html --reporter=text ava",
     "coverage": "nyc report --reporter=text-lcov | coveralls"
   },
-  "license": "MIT"
+  "license": "MIT",
+  "dependencies": {
+    "semver": "^5.5.0"
+  }
 }
diff --git a/src/parser.js b/src/parser.js
index 3fc8a44..a489fe8 100644
--- a/src/parser.js
+++ b/src/parser.js
@@ -1,3 +1,4 @@
+import semver from 'semver';
 import browserParsersList from './parser-browsers';
 import osParsersList from './parser-os';
 import platformParsersList from './parser-platforms';
@@ -271,6 +272,47 @@ class Parser {
   getResult() {
     return this.parsedResult;
   }
+
+  /**
+   * Check if parsed browser matches certain conditions
+   *
+   * @param {Object} checkTree — It's one or two layered object,
+   * which can include a platform or an OS on the first layer
+   * and should have browsers specs on the bottom-laying layer
+   *
+   * @example
+   * const browser = new Bowser(UA);
+   * if (browser.check({chrome: '>118.01.1322' }))
+   * // or with os
+   * if (browser.check({windows: { chrome: '>118.01.1322' } }))
+   * // or with platforms
+   * if (browser.check({desktop: { chrome: '>118.01.1322' } }))
+   */
+  check(checkTree) {
+    const thisVersion = this.getBrowser().version;
+    if (!semver.valid(semver.coerce(thisVersion))) {
+      throw new Error(`Version of current browser doesn't seem applicable: ${thisVersion}`);
+    }
+    const keysToProcess = Object.keys(checkTree);
+    keysToProcess.some((browserAttribute) => {
+      const objectOrVersion = checkTree[browserAttribute];
+
+      if (typeof objectOrVersion === 'object') {
+        return (this.isOs(browserAttribute) || this.isPlatform(browserAttribute))
+          && this.check(objectOrVersion);
+      }
+
+      return this.isBrowser(browserAttribute) && this.matches(objectOrVersion);
+    });
+  }
+
+  isBrowser(browserName) {
+    return this.getBrowser().name === browserName;
+  }
+
+  satisfies(version) {
+    return semver.satisfies(this.getBrowser().version, version);
+  }
 }
 
 export default Parser;