Tile windowing system

app/components/windows/treeUtils.ts

@@ -0,0 +1,75 @@
+import { TileNode, LeafNode, ContainerNode, PanelId } from "./types";
+
+let _id = 0;
+export function gid(): string {
+	return `wn-${Date.now()}-${++_id}`;
+}
+
+// ── Leaf operations ───────────────────────────────────────────────────────────
+
+function mapLeaf(tree: TileNode, leafId: string, fn: (leaf: LeafNode) => TileNode): TileNode {
+	if (tree.type === "leaf") return tree.id === leafId ? fn(tree) : tree;
+	return { ...tree, children: tree.children.map((c) => mapLeaf(c, leafId, fn)) };
+}
+
+export function splitLeaf(
+	tree: TileNode,
+	leafId: string,
+	dir: "h" | "v",
+	newFirst: boolean,
+	newPanelId: PanelId,
+): TileNode {
+	const newLeaf: LeafNode = { type: "leaf", id: gid(), panelId: newPanelId };
+	return mapLeaf(tree, leafId, (leaf) => ({
+		type: "container",
+		id: gid(),
+		dir,
+		children: newFirst ? [newLeaf, leaf] : [leaf, newLeaf],
+		sizes: [1, 1],
+	}));
+}
+
+export function closeLeaf(tree: TileNode, leafId: string): TileNode | null {
+	if (tree.type === "leaf") return tree.id === leafId ? null : tree;
+	const children: TileNode[] = [];
+	const sizes: number[] = [];
+	tree.children.forEach((c, i) => {
+		const r = closeLeaf(c, leafId);
+		if (r !== null) { children.push(r); sizes.push(tree.sizes[i]); }
+	});
+	if (children.length === 0) return null;
+	if (children.length === 1) return children[0]; // collapse single-child container
+	return { ...tree, children, sizes };
+}
+
+export function updatePanelId(tree: TileNode, leafId: string, panelId: PanelId): TileNode {
+	if (tree.type === "leaf") return tree.id === leafId ? { ...tree, panelId } : tree;
+	return { ...tree, children: tree.children.map((c) => updatePanelId(c, leafId, panelId)) };
+}
+
+export function patchSizes(tree: TileNode, containerId: string, sizes: number[]): TileNode {
+	if (tree.type === "leaf") return tree;
+	if (tree.id === containerId) return { ...tree, sizes };
+	return { ...tree, children: tree.children.map((c) => patchSizes(c, containerId, sizes)) };
+}
+
+// ── Query helpers ─────────────────────────────────────────────────────────────
+
+export function getFirstLeafId(tree: TileNode): string {
+	if (tree.type === "leaf") return tree.id;
+	return getFirstLeafId(tree.children[0]);
+}
+
+export function countLeaves(tree: TileNode): number {
+	if (tree.type === "leaf") return 1;
+	return tree.children.reduce((s, c) => s + countLeaves(c), 0);
+}
+
+export function getLeafPanel(tree: TileNode, leafId: string): PanelId | null {
+	if (tree.type === "leaf") return tree.id === leafId ? tree.panelId : null;
+	for (const c of tree.children) {
+		const p = getLeafPanel(c, leafId);
+		if (p) return p;
+	}
+	return null;
+}