select-xamarin-sdk-v2 (#3290)

* select-xamarin-sdk-v2

* Update select-xamarin-sdk-v2.sh

* change warning message

* check existed framework version

* check framework version review points

images/macos/provision/assets/select-xamarin-sdk-v2.sh

@@ -0,0 +1,46 @@
+#!/bin/bash -e -o pipefail
+get_framework_path() {
+  case $1 in
+  --mono) echo '/Library/Frameworks/Mono.framework/Versions' ;;
+  --ios) echo '/Library/Frameworks/Xamarin.iOS.framework/Versions' ;;
+  --android) echo '/Library/Frameworks/Xamarin.Android.framework/Versions' ;;
+  --mac) echo '/Library/Frameworks/Xamarin.Mac.framework/Versions' ;;
+  *) ;;
+  esac
+}
+
+change_framework_version() {
+  local framework=$1
+  local version=$2
+
+  echo "Select $framework $version"
+
+  local countDigit=$(echo "${version}" | grep -o "\." | grep -c "\.")
+
+  if [[ countDigit -gt 1 ]]; then
+    echo "[WARNING] It is not recommended to specify the exact framework version because your build can be broken with the next patch update. Consider using "major.minor" only format."
+  fi
+
+  local framework_path=$(get_framework_path "$framework")
+
+  if [ -d "${framework_path}/${version}" ]; then
+    sudo rm -f "${framework_path}/Current"
+    sudo ln -s "${framework_path}/${version}" "${framework_path}/Current"
+  else
+    echo "Invalid framework version ${framework_path}/${version}"
+    exit 1
+  fi
+}
+
+for arg in "$@"; do
+  key=$(echo $arg | cut -f1 -d=)
+  value=$(echo $arg | cut -f2 -d=)
+
+  case $key in
+  --mono | --ios | --android | --mac) change_framework_version $key $value ;;
+  *)
+  echo "Invalid parameter <${key}>"   
+  exit 1
+  ;;
+  esac
+done