flash_FP4_factory.sh: Be friendly to an user who's upgrading

set -e

set -u

CLEAN_FLASH="true" # Control data wipe behavior. Default is "true".

CLEAN_FLASH="true" # Control data wipe behavior. "true" -> Prompts user if upgrade and if he agrees to wipe

# Target device info

PRODUCT="Fairphone 4"

# Warn about data wipe, and ask for confirmation

data_wipe_check() {

  if [ "${CLEAN_FLASH}" = "true" ]

  then

    local is_upgrade

    local is_wipe

    echo ""

    echo "Q: Are you upgrading from a previous installation of /e/ OS ?"

    read -rp " Type \"Yes\" and press enter to confirm upgrading. ELSE, just press Enter: " is_upgrade

    if [ "${is_upgrade,,}" != "yes" ]

    then

       echo ""

    echo "WARNING: Flashing this image wipes all user data and settings on the phone."

    echo " Are you sure you want to wipe data and continue?"

       echo "WARNING: You did NOT type \"Yes\", assuming you are NOT upgrading from an installation of /e/ OS"

       echo "WARNING: Flashing this image requires wiping all user data and settings on the phone."

       echo "Q: Are you sure you want to wipe data and continue?"

       echo ""

       # Read user's input

    read -rp " Type \"Yes\" (case sensitive) and press enter to wipe data and continue. Else, just press enter: " a

       read -rp " Type \"Yes\" and press enter to wipe data and continue. ELSE, just press enter: " is_wipe

       echo ""

    if [ "_${a:-"No"}" != '_Yes' ]

      # NOTE: $a is being set by the read command above,

      #   so the check for a to be set is mostly redundant

       if [ "${is_wipe,,}" != 'yes' ]

       then

         echo "WARNING: You DID NOT type \"Yes\", proceeding without data wipe."

         echo "WARNING: You DID NOT type \"Yes\", cannot proceed without data wipe for a new installation"

         echo ""

         CLEAN_FLASH="false"

         exit 1

       else

         echo "WARNING: You typed \"Yes\", proceeding with data wipe."

         CLEAN_FLASH="true"

       fi

    else

       echo "WARNING: You typed \"Yes\", assuming you are upgrading from an installation of /e/ OS"

       echo "WARNING: Proceeding without data wipe!"

       CLEAN_FLASH="false"

    fi

  fi

}