Restructure frontend TS files so managers/stores export destructors instead of returning them from their constructors

[Keavon]

No description provided.

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly refactors the frontend architecture by introducing explicit creation and destruction functions for managers and stores, enhancing modularity and HMR compatibility. It also adds a mechanism for the frontend to request a full resend of UI layouts from the backend, addressing potential state loss during HMR. Minor improvements include converting a Rust enum to a macro for better maintainability and adding a new ESLint rule for stricter TypeScript.

Highlights

• Frontend Architecture Refactor: The frontend managers and stores have been refactored to use explicit createManager/destroyManager and createStore/destroyStore functions, moving away from global currentCleanup/currentArgs variables for HMR. This improves modularity and hot-module replacement (HMR) reliability.
• Layout Resend Mechanism: A new ResendAllLayouts message and corresponding handler have been added to the Rust backend. This allows the frontend to request a full resend of all UI layouts, which is crucial for restoring UI state after an HMR re-mount.
• LayoutTarget Macro: The LayoutTarget enum in Rust has been converted into a macro, simplifying its definition and ensuring consistency.
• ESLint Rule Addition: A new ESLint rule @typescript-eslint/no-non-null-assertion has been added to the frontend configuration, enforcing stricter TypeScript practices.

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[gemini-code-assist]

Code Review

This pull request introduces significant architectural changes to the frontend, primarily focusing on improving resource management and Hot Module Replacement (HMR) compatibility. The refactoring shifts from returning manager/store instances with destroy methods to using module-scoped variables and explicit create and destroy functions. This centralizes resource cleanup in Editor.svelte's onDestroy lifecycle hook, which is a cleaner approach for managing subscriptions and event listeners during HMR re-mounts. The addition of ResendAllLayouts in the Rust backend and its invocation in the frontend ensures UI state consistency after HMR. The new define_layout_target! macro in Rust is a good improvement for enum definition maintainability. The ESLint rule addition for non-null assertions enhances type safety. Overall, these changes are well-considered and improve the robustness and maintainability of the application.

[cubic-dev-ai]

4 issues found across 21 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="frontend/src/managers/persistence.ts">

<violation number="1" location="frontend/src/managers/persistence.ts:44">
P2: Create and reuse one module-level `idb.createStore(...)` instead of recreating it in each function/handler.</violation>
</file>

<file name="frontend/src/managers/fonts.ts">

<violation number="1" location="frontend/src/managers/fonts.ts:9">
P2: The module-scoped AbortController is reused after being aborted, so fetches fail after manager teardown/recreation (including HMR).</violation>
</file>

<file name="frontend/src/stores/app-window.ts">

<violation number="1" location="frontend/src/stores/app-window.ts:32">
P2: Overwriting a single global `editorRef` makes store cleanup instance-unsafe; re-creating the store before teardown can leak old frontend message subscriptions.</violation>
</file>

<file name="frontend/src/managers/input.ts">

<violation number="1" location="frontend/src/managers/input.ts:555">
P1: Unconditional `app?.focus()` steals focus on every input event. In the original code, focus was only restored when `!canvasFocused && newInCanvasArea`. This line forces focus to the app container on every pointer move, key press, etc., breaking text inputs, menus, and all non-canvas interactions. Remove this line — the conditional `app?.focus()` inside the `if` block below handles the intended behavior.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}