PrismCompositionModel

@zephytiju/prism-composition-model is the runtime-neutral source of truth for Prism Operating System and UI-page documents. It publishes pure TypeScript types, deterministic canonical JSON and SHA-256 digests, validators, layout-variant materialization, versioned migrations, and conformance fixtures.

The package contains no transport, persistence, foundation client, UI state, service wire model, or runtime variant resolver.

Contract

• Operating Systems pin ordered immutable UI-page revisions.
• UI-page revisions pin exact layout-template releases and exact Blueprint component versions.
• layoutConfig is the runtime authority for an instance.
• appliedLayoutVariant is optional authoring provenance and is retained only while its exact component release, binding fingerprint, key, and digest match the materialized layout.
• Manual edits and component-version changes clear preset provenance and therefore represent Custom without changing component configuration, bindings, placement, peers, or the page template.

import { applyLayoutVariant, canonicalDigest } from "@zephytiju/prism-composition-model";

const layoutConfigDigest = await canonicalDigest(layoutConfig);
const updated = await applyLayoutVariant(instance, {
  componentRelease: instance.componentRelease,
  bindingFingerprint: instance.bindingFingerprint,
  key: "dense",
  layoutConfig,
  layoutConfigDigest,
});

Run npm run verify to build, execute conformance vectors, and verify the publishable package contents.

Selected split allocation (1.1)

LayoutNode.splitAllocation is optional page state for an exact template-declared resizable split: { version: 1, shares: [{ childId, units }] }. Every immediate child occurs once, in child order, with positive integer units totaling 1,000,000. Omission preserves legacy documents, template releases and canonical digests.

canonicalSplitAllocation validates unknown JSON; splitAllocationFromWeights uses largest remainder with child-order ties and rejects zero-unit results. canonicalizeSplitAllocations and validateUIPageRevision(page, templateDefinition) require the exact template policy for any explicit allocation. The model does not resolve or publish templates. Services remain responsible for exact-reference, whole-page, authorization and concurrency checks.

editSplitLayout(tree, splitId, templateDefinition, edit, innerExtentPx) performs atomic resize, keyboard resize, add, empty-child removal and reorder operations. The available extent excludes external panels, gaps and dividers. Keep the old tree for undo; persist only the resulting canonical page tree. resolveSplitPixels applies the template axis and size bounds without changing saved shares and returns fallback when the viewport cannot fit them. Tabs, collapse and responsive adapters retain the saved allocation and resolve it again on restoration.

The ./fixtures subpath includes splitAllocationVectors for service and Build conformance. New writes require compatible Composition, SDK, Build Service and Builder readers; old strict readers must reject unsupported fields without stripping them.