[1/2] Add support for multiple accounts in config | Fix labbots#98

Add four new flags

* -a | --account - Use a different account than default

* -la | --list accounts - List all the accounts configured with CLIENT_ID, CLIENT_SECRET and REFRESH_TOKEN

* -ca | --create-account - Create a new account

* -da | --delete-account - Delete an existing account

The config format is changed, ACCOUNT_${account}_ prefix is added to every config var, where ${account} si the account name

The old configs will be automatically migrated with account name default( if default taken then a number suffix will be added like default1, default2, etc )

move authentication/config related functions to auth-utils.[bash|sh]

bash/common-utils.bash

@@ -272,6 +272,23 @@ _print_center() {
     return 0
 }
 
+###################################################
+# Evaluates value1=value2
+# Globals: None
+# Arguments: 3
+#   ${1} = direct ( d ) or indirect ( i ) - ( evaluation mode )
+#   ${2} = var name
+#   ${3} = var value
+# Result: export value1=value2
+###################################################
+_set_value() {
+    mode="${1:?}" var="${2:?}" value="${3:?}"
+    case "${mode}" in
+        d | direct) export "${var}=${value}" ;;
+        i | indirect) export "${var}=${!value}" ;;
+    esac
+}
+
 ###################################################
 # Check if script terminal supports ansi escapes
 # Globals: 1 variable

bash/drive-utils.bash

@@ -177,28 +177,6 @@ _extract_id() {
     printf "%b" "${ID:+${ID}\n}"
 }
 
-###################################################
-# Method to regenerate access_token ( also updates in config ).
-# Make a request on https://www.googleapis.com/oauth2/""${API_VERSION}""/tokeninfo?access_token=${ACCESS_TOKEN} url and check if the given token is valid, if not generate one.
-# Globals: 9 variables, 2 functions
-#   Variables - CLIENT_ID, CLIENT_SECRET, REFRESH_TOKEN, TOKEN_URL, CONFIG, API_URL, API_VERSION, QUIET, NO_UPDATE_TOKEN
-#   Functions - _update_config and _print_center
-# Result: Update access_token and expiry else print error
-###################################################
-_get_access_token_and_update() {
-    RESPONSE="${1:-$(curl --compressed -s -X POST --data "client_id=${CLIENT_ID}&client_secret=${CLIENT_SECRET}&refresh_token=${REFRESH_TOKEN}&grant_type=refresh_token" "${TOKEN_URL}")}" || :
-    if ACCESS_TOKEN="$(_json_value access_token 1 1 <<< "${RESPONSE}")"; then
-        ACCESS_TOKEN_EXPIRY="$(($(printf "%(%s)T\\n" "-1") + $(_json_value expires_in 1 1 <<< "${RESPONSE}") - 1))"
-        _update_config ACCESS_TOKEN "${ACCESS_TOKEN}" "${CONFIG}"
-        _update_config ACCESS_TOKEN_EXPIRY "${ACCESS_TOKEN_EXPIRY}" "${CONFIG}"
-    else
-        "${QUIET:-_print_center}" "justify" "Error: Something went wrong" ", printing error." "=" 1>&2
-        printf "%s\n" "${RESPONSE}" 1>&2
-        return 1
-    fi
-    return 0
-}
-
 ###################################################
 # Upload ( Create/Update ) files on gdrive.
 # Interrupted uploads can be resumed.

bash/release/gsync

@@ -273,6 +273,23 @@ _print_center() {
     return 0
 }
 
+###################################################
+# Evaluates value1=value2
+# Globals: None
+# Arguments: 3
+#   ${1} = direct ( d ) or indirect ( i ) - ( evaluation mode )
+#   ${2} = var name
+#   ${3} = var value
+# Result: export value1=value2
+###################################################
+_set_value() {
+    mode="${1:?}" var="${2:?}" value="${3:?}"
+    case "${mode}" in
+        d | direct) export "${var}=${value}" ;;
+        i | indirect) export "${var}=${!value}" ;;
+    esac
+}
+
 ###################################################
 # Check if script terminal supports ansi escapes
 # Globals: 1 variable