initrd/etc/gui_functions pause_automatic_boot: show UTC timestamp + TOTP code while waiting for automatic boot when a default boot is set and hotp is valid

Signed-off-by: Thierry Laurion <insurgo@riseup.net>

Author: tlaurion

initrd/etc/gui_functions

@@ -5,10 +5,47 @@
 # Pause for the configured timeout before booting automatically.  Returns 0 to
 # continue with automatic boot, nonzero if user interrupted.
 pause_automatic_boot() {
-	if IFS= read -t "$CONFIG_AUTO_BOOT_TIMEOUT" -s -n 1 -r -p \
-		$'Automatic boot in '"$CONFIG_AUTO_BOOT_TIMEOUT"$' seconds unless interrupted by keypress...\n'; then
-		return 1 # Interrupt automatic boot
+	local remaining="$CONFIG_AUTO_BOOT_TIMEOUT"
+	
+	# Calculate boot time for initial message
+	local now_epoch boot_epoch boot_str
+	now_epoch=$(date -u +%s)
+	boot_epoch=$((now_epoch + CONFIG_AUTO_BOOT_TIMEOUT))
+	boot_str=$(date -u -d "@$boot_epoch" '+%Y-%m-%d %H:%M:%S UTC' 2>/dev/null)
+	if [ -z "$boot_str" ]; then
+		boot_str="(epoch: $boot_epoch)"
 	fi
+	echo "Automatic boot in $CONFIG_AUTO_BOOT_TIMEOUT seconds at $boot_str unless interrupted by keypress..."
+	printf "\n" # Reserve space for the updating line
+
+	while [ $remaining -gt 0 ]; do
+		local now_epoch now_str status_line
+		now_epoch=$(date -u +%s)
+		now_str=$(date -u '+%Y-%m-%d %H:%M:%S UTC')
+		status_line="$now_str | Booting in $remaining seconds..."
+
+		if [ "$CONFIG_TPM" = "y" ] && [ "$CONFIG_TOTP_SKIP_QRCODE" != "y" ]; then
+			# Get current TOTP if available and not skipped
+			local current_totp
+			if ! current_totp=$(unseal-totp 2>/dev/null); then
+				die "Failed to unseal TOTP"
+			fi
+			status_line="$status_line | TOTP: $current_totp"
+		fi
+
+		# Update the status line in place
+		printf "\r%s" "$status_line"
+
+		# Check for keypress
+		if IFS= read -t 1 -s -n 1 -r; then
+			printf "\n" # New line after interrupt
+			return 1 # Interrupt automatic boot
+		fi
+
+		remaining=$((remaining - 1))
+	done
+
+	printf "\n" # New line after countdown
 	return 0 # Continue with automatic boot
 }