audit-large-files

name	audit-large-files
description	Audit for oversized components, hooks, and modules that need decomposition
user-invocable	true

Audit: Large Files & Decomposition

Identify oversized files that hurt maintainability and suggest decomposition. This is a research-only audit — do not modify any code.

What to Search For

File Size Inventory

1. Find all .tsx, .ts, and .rs files. Count lines for each using wc -l via Bash.

2. Flag files over these thresholds:

   • .tsx components: 400 lines — but the decisive metric is the LARGEST single component/function in the file, not the file total. A file may be long because it holds N small co-located components (flag for one-component-per-file, §"Component-count split") or because one function is enormous (flag for in-function decomposition).
   • .ts hooks/stores: 500 lines
   • .rs modules: 1,000 lines

   Record BOTH numbers per flagged file: total_lines and largest_unit_lines. Sort findings by largest_unit_lines — a 2,832-line file whose biggest function is 1,430 lines is a worse offender than a 2,279-line file that is one cohesive parser.

For Each Flagged File, Assess

• Responsibility count: How many distinct concerns does it handle? List them.
• Nested sub-components: Are there components defined inside other component files that should be separate files? Note their line counts.
• Code duplication: Is the same pattern repeated (e.g., similar form fields, similar API call setups)?
• Decomposition plan: What would you extract, and what would remain?

Specific Patterns

• Components with 10+ hooks: A component calling 10+ custom hooks is likely an orchestrator that could delegate to sub-components.
• Hooks mixing concerns: A hook that handles both UI state and backend communication should be split.
• Rust modules with shared code: Two modules implementing the same protocol (e.g., JSON-RPC) should share a common module.
• Settings panels with nested dialogs: Dialog components defined inline in a settings file should be separate files.
• N components in one file (one-component-per-file violation): Count top-level component declarations per .tsx file (function PascalCase, const PascalCase = ( returning JSX). A file holding ≥3 independently- renderable components is a split candidate REGARDLESS of total line count — each component subscribes to different stores and is independently testable, so co-location defeats isolated re-render reasoning and unit testing. Report each sub-component with its start line and estimated size. The target shape is a layout shell that composes one-file-each children (e.g. an 1,148-line StatusBar.tsx packing 11 components, or a command-bar file holding 9).
• Module-scope mutable state in a hook file: Grep flagged hook modules for top-level let bindings and module-scope mutators/getters (e.g. exported free functions that read/write those lets). State that a React hook mutates but stores at MODULE scope is a hidden global — it works only because the app mounts the hook exactly once, and it breaks under StrictMode double-invoke and any future multi-window. Flag it as a boundary leak: the state belongs in the store that owns the corresponding UI (per the Zustand store inventory in architecture.md), not in a hook module. Recommend moving it into that store and reducing the hook to a thin orchestrator (e.g. a lifecycle hook holding let _homeDir / eager-session promises / timer ids that belong in a status store).
• A core contract surface buried under a converter/helper bank: When a module mixes a documented, contract-bearing API (e.g. the markdown↔ProseMirror round-trip in src/lib/markdown.ts) with a large bank of same-shaped helper functions (15× convert*ToHtml), the helpers should move to a sibling module with a re-export for compatibility, leaving the contract surface readable in isolation. Detection heuristic: ≥8 functions sharing a naming prefix (convertXToY, parseX, handleX) inside a file that ALSO exports a small set of architecturally-load-bearing functions.
• Rust command module mixing #[tauri::command] handlers with lifecycle/ catalog/transport logic: A commands/*.rs file that holds both the IPC command surface AND substantial non-command machinery (process lifecycle, embedded catalogs, FIM/transport plumbing) is a split candidate. Separate the thin command layer from the implementation module it delegates to (e.g. an acp.rs mixing commands with session-lifecycle, or a local_inference.rs mixing lifecycle + catalog + FIM).

Output Format

Report findings as a table for overview, then detailed entries for the largest files:

### Files Over Threshold

| File | Lines | Threshold | Responsibilities |
| --- | --- | --- | --- |
| `FloatingCommandBar.tsx` | 2,832 | 400 | 5+ (chat surface, prefix modes, resize, attachments, a11y) |

### HIGH: FloatingCommandBar.tsx — 2,832 lines, 5+ responsibilities, main fn ~1,430 lines

**File:** `src/components/cmd/FloatingCommandBar.tsx`

**Current responsibilities:**
1. Chat surface (the documented "chat panel")
2. Prefix-mode picker dispatch (`/`, `@`, `#`, `!`, `?`, `>`)
3. Pinned-panel resize + width/height state machine
4. Attachment chips
5. Combobox/listbox accessibility wiring

Holds 9 top-level components in one file: the main `FloatingCommandBar`,
`PinnedResizeHandle`, `ExpandedResizeHandle`, `TopResizeHandle`,
`CompactContent`, `ExpandedContent`, `PrefixModeBadge`,
`ModePickerDispatch`, `VerbDiscoveryMenu`. ~80 hook/effect call sites.

**Recommended extraction:**

| Extract to | Lines | Responsibility |
| --- | --- | --- |
| `cmd/resize/{Pinned,Expanded,Top}ResizeHandle.tsx` | ~130 each | Drag-resize handles |
| `cmd/CompactContent.tsx`, `cmd/ExpandedContent.tsx` | ~130 / ~510 | Bar body states |
| `cmd/ModePickerDispatch.tsx`, `cmd/VerbDiscoveryMenu.tsx` | ~95 / ~40 | Prefix/verb pickers |
| `useCommandBarGeometry.ts` | ~150 | `PINNED_*`/`EXPANDED_*` constants + resize state machine |
| `FloatingCommandBar.tsx` (remaining) | <500 | Thin orchestrator |

Decomposition Heuristics (rank, don't just count)

Line count is a trigger, not a verdict. Before recommending a split, score each flagged file on:

1. Largest-unit size — the single biggest function/component (see threshold note). This is the primary rank key.
2. Responsibility count — distinct concerns in the main unit. ≥3 → split.
3. Cohesion — would the extracted pieces share state/imports, or are they independent? A 2,000-line file that is ONE responsibility with high internal cohesion (a binary parser, a single-format converter) is ACCEPTABLE; record it in the acceptable list, do not recommend a split.
4. Churn — is this a high-traffic file (the chat surface, the main editor)? High churn × high size = highest priority because merge conflicts and review load concentrate there.

Worked contrast: a 2,279-line cohesive parser and a 2,168-line single-format converter are left ACCEPTABLE (one responsibility, high internal cohesion), while a 1,148-line status bar is flagged HIGH despite being smaller — because it is 11 responsibilities, not one.

End with a section listing files that are large but acceptable (specialized viewers, type definition files, declarative toolbar configs) to avoid flagging them in future audits.

Confirmed cohesive in a recent pass — do NOT re-flag for size alone:

• src/lib/pptx-parser.ts (~2,279) — single-responsibility PPTX parser
• src-tauri/src/export/markdown_to_docx.rs (~2,168) — single-format converter
• src-tauri/src/export/markdown_to_pptx.rs (~1,776) — single-format converter
• src-tauri/src/commands/copilot_lsp.rs (~1,409) — cohesive LSP orchestrator

Test files are expected to be large and are out of scope (e.g. settings-store.test.ts, useAgentTaskOperations.test.ts). Always exclude *.test.* from the size inventory ranking.

Example Finding

HIGH: ConnectionsSettings — 1,685 lines with 468-line nested component

File: src/components/settings/ConnectionsSettings.tsx

Contains ConnectAgent (468 lines) and ConnectCopilotLsp (384 lines) defined inline. Each manages a complete auth flow that could be tested independently.

Recommended extraction:

Extract to	Lines	Responsibility
ConnectAgent.tsx	468	Agent install guides + auth flow
ConnectCopilotLsp.tsx	384	Device code flow + browser integration
SetupGuideView.tsx	156	Shared setup guide UI
ConnectionsSettings.tsx (remaining)	~400	Connection list + add flow orchestration