Add data migration logic

entrypoint.sh

@@ -9,8 +9,29 @@ echo "everything from scratch. For more information about the new version, check
 echo "https://github.com/shenxn/protonmail-bridge-docker"
 echo
 
+if [ -d /root/.config/protonmail ]; then
+    echo "Volume mount at `/root` for old version found. Please change your mount path to `/protonmail/data`."
+    echo "See https://github.com/shenxn/protonmail-bridge-docker for detailed migration guide."
+    echo "Exit in 30 seconds..."
+    sleep 30
+    exit 1
+fi
+
 groupadd -g ${PROTON_GID:-1001} proton
 useradd -g proton -u ${PROTON_UID:-1001} -m proton
-chown proton:proton -R /protonmail/data
+chown proton:proton /protonmail/data
+
+# Migrate old version data
+if [ -d /protonmail/data/.config/protonmail ]; then
+    echo "Migrating legacy data. Note that this operation is irreversible so it is impossible"
+    echo "to go back to the old version without clearing the volume."
+    echo
+
+    mv /protonmail/data/.config/protonmail /protonmail/data/config
+    rm -rf /protonmail/data/.config
+    mv /protonmail/data/.cache/protonmail /protonmail/data/cache
+    rm -rf /protonmail/data/.cache
+    chown proton:proton -R /protonmail/data
+fi
 
 exec gosu proton:proton run_protonmail_bridge.sh "$@"