Add support for brackets in parser

+ identifies facebook app user agent

ua.go

@@ -56,6 +56,8 @@ const (
 	FacebookExternalHit = "facebookexternalhit"
 	Applebot            = "Applebot"
 	Bingbot             = "Bingbot"
+
+	FacebookApp = "Facebook App"
 )
 
 // Parse user agent string returning UserAgent struct
@@ -246,6 +248,9 @@ func Parse(userAgent string) UserAgent {
 			ua.Mobile = true
 		}
 
+	case tokens.exists("FBAN"):
+		ua.Name = FacebookApp
+
 	case tokens.get("HuaweiBrowser") != "":
 		ua.Name = "Huawei Browser"
 		ua.Version = tokens.get("HuaweiBrowser")
@@ -349,6 +354,7 @@ func parse(userAgent string) properties {
 	}
 
 	parOpen := false
+	braOpen := false
 
 	bua := []byte(userAgent)
 	for i, c := range bua {
@@ -359,13 +365,20 @@ func parse(userAgent string) properties {
 			addToken()
 			parOpen = false
 
-		case parOpen && c == 59: // ;
+		case (parOpen || braOpen) && c == 59: // ;
 			addToken()
 
 		case c == 40: // (
 			addToken()
 			parOpen = true
 
+		case c == 91: // [
+			addToken()
+			braOpen = true
+		case c == 93: // ]
+			addToken()
+			braOpen = false
+
 		case slash && c == 32:
 			addToken()
 

ua_test.go

@@ -91,6 +91,9 @@ var testTable = [][]string{
 	// HeadlessChrome
 	{"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/98.0.4758.0 Safari/537.36", ua.HeadlessChrome, "98.0.4758.0", "desktop", ua.Linux},
 
+	//FB App
+	{"Mozilla/5.0 (iPhone; CPU iPhone OS 15_4_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Mobile/19E258 [FBAN/FBIOS;FBDV/iPhone8,2;FBMD/iPhone;FBSN/iOS;FBSV/15.4.1;FBSS/3;FBID/phone;FBLC/fr_FR;FBOP/5]", ua.FacebookApp, "FBIOS", "mobile", ua.IOS},
+
 	// other
 	{"Mozilla/5.0 (X11; CrOS x86_64 14150.74.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.114 Safari/537.36", ua.Chrome, "94.0.4606.114", "desktop", ua.ChromeOS},
 	{"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36 Google (+https://developers.google.com/+/web/snippet/)", ua.Chrome, "56.0.2924.87", "bot", ua.Linux}, // Google+ fetch
@@ -108,6 +111,7 @@ var testTable = [][]string{
 	//GooglePlus   "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36 Google (+https://developers.google.com/+/web/snippet/)"
 	//Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/600.2.5 (KHTML, like Gecko) Version/8.0.2 Safari/600.2.5 (Applebot/0.1; +http://www.apple.com/go/applebot)
 	//Mozilla/5.0 (Macintosh; Intel Mac OS Xt 10_11_4) AppleWebKit/537.36 (KHTML, like Gecko) QtWebEngine/5.6.0 Chrome/45.0.2454.101 Safari/537.36
+
 }
 
 func TestParse(t *testing.T) {