From 539ece97f493872ad1564f54cb743d17fcf79edf Mon Sep 17 00:00:00 2001
From: Claude Brisson <claude@renegat.net>
Date: Thu, 9 May 2024 06:53:38 +0200
Subject: [PATCH] Protection against non-parsable Accept-Language header

---
 .../kotlin/org/jeudego/pairgoth/view/CountriesTool.kt     | 4 ++++
 view-webapp/src/main/webapp/tour-information.inc.html     | 8 +++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/view-webapp/src/main/kotlin/org/jeudego/pairgoth/view/CountriesTool.kt b/view-webapp/src/main/kotlin/org/jeudego/pairgoth/view/CountriesTool.kt
index 17e5095..9f47f36 100644
--- a/view-webapp/src/main/kotlin/org/jeudego/pairgoth/view/CountriesTool.kt
+++ b/view-webapp/src/main/kotlin/org/jeudego/pairgoth/view/CountriesTool.kt
@@ -2,6 +2,7 @@ package org.jeudego.pairgoth.view
 
 import org.apache.velocity.tools.config.ValidScope
 import org.jeudego.pairgoth.web.WebappManager
+import org.slf4j.LoggerFactory
 import javax.servlet.http.HttpServletRequest
 
 @ValidScope("request")
@@ -19,12 +20,15 @@ class CountriesTool {
             countries[iso]?.let { name ->
                 Pair(iso, name)
             }
+        } ?: null.also {
+            logger.warn("could not get country from Accept-Language header: ${request.getHeader("Accept-Language")}")
         }
     }
 
     public fun getCountries() = countries.entries.sortedBy { it.value }
 
     companion object {
+        val logger = LoggerFactory.getLogger("view")
         private val langHeaderParser = Regex("(?:\\b(\\*|[a-z]{2})(?:(?:_|-)([a-z]{2}))?)(?:;q=([0-9.]+))?", RegexOption.IGNORE_CASE)
         public val countries = mapOf(
             "ad" to "Andorra",
diff --git a/view-webapp/src/main/webapp/tour-information.inc.html b/view-webapp/src/main/webapp/tour-information.inc.html
index 2aa07df..158e6fb 100644
--- a/view-webapp/src/main/webapp/tour-information.inc.html
+++ b/view-webapp/src/main/webapp/tour-information.inc.html
@@ -25,7 +25,13 @@
           <span class="info"></span>
           <select name="country" placeholder="country">
             <option></option>
-#set($defaultCountry = $countries.country.first)
+#set($countryFromPreferredLanguage = $countries.country)
+#if($countryFromPreferredLanguage)
+  #set($defaultCountry = $countryFromPreferredLanguage.first)
+#else
+  ## Accept-Language could not be parsed
+  #set($defaultCountry = 'en')
+#end
 #foreach($country in $countries.countries)
             <option value="$country.key" #if($tour && $country.key.toLowerCase() == $tour.country.toLowerCase() || !$tour && $country.key.toLowerCase() == $defaultCountry.toLowerCase()) selected #end>$country.value</option>
 #end