[Init] Initial commit - NetMesh terminal manager

domain/serialBackspace.ts

@@ -0,0 +1,38 @@
+import type { GroupConfig, Host, SerialConfig } from "./models";
+
+export type SerialBackspaceBehavior = NonNullable<SerialConfig["backspaceBehavior"]>;
+
+export const prepareSerialConfigForSavedHost = (
+  config: SerialConfig,
+): SerialConfig => {
+  const { backspaceBehavior, ...rest } = config;
+  return backspaceBehavior === "ctrl-h"
+    ? { ...rest, backspaceBehavior }
+    : rest;
+};
+
+export const resolveSerialBackspaceFormValue = (
+  host: Pick<Host, "serialConfig" | "backspaceBehavior">,
+  groupDefaults?: Pick<GroupConfig, "backspaceBehavior">,
+): SerialBackspaceBehavior => (
+  host.serialConfig?.backspaceBehavior
+  ?? (host.backspaceBehavior === "ctrl-h" ? "ctrl-h" : undefined)
+  ?? (groupDefaults?.backspaceBehavior === "ctrl-h" ? "ctrl-h" : "default")
+);
+
+export const resolveSerialBackspaceOverrideOnSave = ({
+  initialHost,
+  selectedBehavior,
+  behaviorChanged,
+}: {
+  initialHost: Pick<Host, "serialConfig" | "backspaceBehavior">;
+  selectedBehavior: SerialBackspaceBehavior;
+  behaviorChanged: boolean;
+}): SerialConfig["backspaceBehavior"] => {
+  const hasExplicitBehavior = initialHost.serialConfig?.backspaceBehavior !== undefined
+    || initialHost.backspaceBehavior === "ctrl-h";
+
+  return hasExplicitBehavior || behaviorChanged
+    ? selectedBehavior
+    : undefined;
+};