1 files changed, 179 insertions, 0 deletions
diff --git a/src/domains/ax-tree.ts b/src/domains/ax-tree.ts
new file mode 100644
index 0000000..1329063
--- /dev/null
+++ b/src/domains/ax-tree.ts
@@ -0,0 +1,179 @@
+import type { AxNodeResult } from "../cdp/commands";
+import type { BrowserClient } from "../client";
+import type { Box } from "./box";
+import { cdpCall } from "./cdp-call";
+
+export type RawAxNode = AxNodeResult;
+type AxValue = NonNullable<RawAxNode["role"]>;
+
+export type SlimNode = {
+  role: string;
+  name?: string;
+  value?: string;
+  description?: string;
+  state?: string;
+  children: SlimNode[];
+  _backendId?: number;
+  ref?: string;
+  box?: Box;
+};
+
+export const INTERACTIVE_ROLES = new Set([
+  "button",
+  "link",
+  "textbox",
+  "checkbox",
+  "radio",
+  "combobox",
+  "menuitem",
+  "tab",
+  "switch",
+  "slider",
+  "searchbox",
+  "spinbutton",
+]);
+
+// The AX `value` is stale for freshly-typed or controlled inputs, so for these roles the live DOM property is read instead.
+export const VALUE_ROLES = new Set([
+  "textbox",
+  "searchbox",
+  "spinbutton",
+  "combobox",
+  "checkbox",
+  "radio",
+  "switch",
+  "slider",
+]);
+
+const stringOf = (v: AxValue | undefined): string | undefined => {
+  const x = v?.value;
+  if (typeof x === "string" && x !== "") return x;
+  if (typeof x === "number") return String(x);
+  return undefined;
+};
+
+const collectState = (props: RawAxNode["properties"]): string | undefined => {
+  if (!props || props.length === 0) return undefined;
+  const flags: string[] = [];
+  for (const p of props) {
+    const name = p.name;
+    if (!name) continue;
+    const raw = p.value?.value;
+    if (raw === true && (name === "focused" || name === "required" || name === "disabled" || name === "checked" || name === "expanded" || name === "selected" || name === "pressed" || name === "modal")) {
+      flags.push(name);
+    }
+    if (typeof raw === "number" && name === "level") flags.push(`level ${raw}`);
+  }
+  return flags.length > 0 ? flags.join(", ") : undefined;
+};
+
+export const buildTree = (
+  rawNodes: ReadonlyArray<RawAxNode>,
+  opts: { interestingOnly: boolean; maxNodes: number },
+): SlimNode[] => {
+  const byId = new Map<string, RawAxNode>();
+  for (const n of rawNodes) byId.set(n.nodeId, n);
+
+  const rootIds: string[] = [];
+  for (const n of rawNodes) {
+    if (!n.parentId || !byId.has(n.parentId)) rootIds.push(n.nodeId);
+  }
+
+  let budget = opts.maxNodes;
+
+  const slim = (node: RawAxNode): SlimNode | undefined => {
+    if (budget <= 0) return undefined;
+    if (opts.interestingOnly && node.ignored) {
+      // Chrome often ignores wrapper divs while their descendants remain meaningful, so recurse through an ignored node's children.
+      const out: SlimNode[] = [];
+      for (const cid of node.childIds ?? []) {
+        const child = byId.get(cid);
+        if (!child) continue;
+        const slimChild = slim(child);
+        if (slimChild) out.push(slimChild);
+      }
+      return out.length > 0 ? { role: "_hoist", children: out } : undefined;
+    }
+    budget--;
+    const role = stringOf(node.role) ?? "unknown";
+    const name = stringOf(node.name);
+    const value = stringOf(node.value);
+    const description = stringOf(node.description);
+    const state = collectState(node.properties);
+    const children: SlimNode[] = [];
+    for (const cid of node.childIds ?? []) {
+      const child = byId.get(cid);
+      if (!child) continue;
+      const slimChild = slim(child);
+      if (!slimChild) continue;
+      if (slimChild.role === "_hoist") children.push(...slimChild.children);
+      else children.push(slimChild);
+    }
+    const out: SlimNode = { role, children };
+    if (name !== undefined) out.name = name;
+    if (value !== undefined) out.value = value;
+    if (description !== undefined) out.description = description;
+    if (state !== undefined) out.state = state;
+    if (node.backendDOMNodeId !== undefined) out._backendId = node.backendDOMNodeId;
+    return out;
+  };
+
+  const result: SlimNode[] = [];
+  for (const rid of rootIds) {
+    const root = byId.get(rid);
+    if (!root) continue;
+    const s = slim(root);
+    if (!s) continue;
+    if (s.role === "_hoist") result.push(...s.children);
+    else result.push(s);
+  }
+  return result;
+};
+
+export const countNodes = (nodes: ReadonlyArray<SlimNode>): number => {
+  let n = 0;
+  for (const node of nodes) n += 1 + countNodes(node.children);
+  return n;
+};
+
+export const stripInternals = (nodes: ReadonlyArray<SlimNode>): SlimNode[] =>
+  nodes.map((n) => {
+    const { _backendId: _bid, ...rest } = n;
+    return { ...rest, children: stripInternals(n.children) };
+  });
+
+export const collectInteractiveTargets = (
+  nodes: ReadonlyArray<SlimNode>,
+): Array<{ node: SlimNode; backendId: number }> => {
+  const out: Array<{ node: SlimNode; backendId: number }> = [];
+  const walk = (ns: ReadonlyArray<SlimNode>): void => {
+    for (const n of ns) {
+      if (n._backendId !== undefined && INTERACTIVE_ROLES.has(n.role)) {
+        out.push({ node: n, backendId: n._backendId });
+      }
+      walk(n.children);
+    }
+  };
+  walk(nodes);
+  return out;
+};
+
+export const liveValue = async (client: BrowserClient, backendId: number): Promise<string | undefined> => {
+  const resolved = await cdpCall(client, "DOM.resolveNode", { backendNodeId: backendId });
+  if (!resolved.success) return undefined;
+  const objectId = resolved.data.object.objectId;
+  if (!objectId) return undefined;
+  const fn = `function () {
+    if (this.type === "checkbox" || this.type === "radio") return this.checked ? "checked" : "unchecked";
+    if (typeof this.value === "string") return this.value;
+    return null;
+  }`;
+  const r = await cdpCall(client, "Runtime.callFunctionOn", {
+    objectId,
+    functionDeclaration: fn,
+    returnByValue: true,
+  });
+  if (!r.success) return undefined;
+  const value = r.data.result.value;
+  return typeof value === "string" ? value : undefined;
+};