multilanguage switcher (NB: add / to the end of 'url' menu entry param)

layouts/partials/footer.html

@@ -1,2 +1,29 @@
+<p>
+    {{ $siteLanguages := .Site.Languages }}
+    {{ $pageLang := .Page.Lang }}
+    
+    {{ $currentPage := . }}
+    {{ $pageName := "" }}
+    {{ range .Site.Menus.main }}
+      {{ if eq ($currentPage.URL | absLangURL) (.URL | absLangURL) }}
+        {{ $pageName = .Name }}
+      {{ end }}
+    {{ end }}
+    
+    {{ range .Page.AllTranslations }}
+      {{ $translation := .}}
+      {{ range $siteLanguages }}
+          {{ if eq $translation.Lang .Lang }}
+            {{ $selected := false }}
+            {{ if eq $pageLang .Lang }}
+                <br/><span class="active">$ echo $LANG<br/><b>{{ .LanguageName }}</b></span><br/>
+            {{ else }}
+                <br/><a href="{{ $translation.URL }}">export LANG={{ .LanguageName }}; ./{{ $pageName }}</a><br/>
+            {{ end }}
+          {{ end }}
+      {{ end }}
+    {{ end }}
+</p>
+<br/><br/>
 <p class="copyright">{{ .Site.Copyright }}</p>
 <p class="advertisement">Powered by <a href="https://gohugo.io/">hugo</a> and <a href="https://github.com/joeroe/risotto">risotto</a>.</p>