@horu2day/pure-cad-cli

Headless pure-cad CLI. AutoCAD accoremgd.dll analog — drives the full CAD engine in a QuickJS-WASM sandbox, without exposing source code or a GUI.

Pipes natural-language → script → DXF/DWG for AI agents (Claude Code, Antigravity, GPT, ...).

Install

Public npm package. No token or .npmrc needed — Node.js 20+ only.

# Permanent install
npm i -g @horu2day/pure-cad-cli

# One-shot
npx @horu2day/pure-cad-cli new --output empty.dxf

CLI

pure-cad run    --script s.js [--input base.dwg] --output out.dwg
pure-cad query  --input drawing.dwg
pure-cad export --input file.dwg --output file.dxf
pure-cad new    --output empty.dwg

All commands print one JSON line to stdout. Errors → stderr with { ok:false, error, code }.

Exit 0 = success, 1 = failure.

Script API (inside --script files)

cad.cmd(NAME, ...args) feeds the arguments to the command's prompts in order. A command that still wants input after the last argument draws nothing, so the argument count matters — see Warnings.

// Drawing
cad.cmd('LINE', '0,0', '100,100'); cad.confirm();     // points…, then confirm
cad.cmd('CIRCLE', '50,50', '25');                     // center, radius
cad.cmd('ARC',    '0,0', '50,50', '100,0');           // start, mid, end
cad.cmd('RECT',   '0,0', '100,50');                   // 2 diagonal corners
cad.cmd('PLINE',  '0,0', '100,0', '100,100', 'C');    // points…, 'C' closes
cad.cmd('POLYGON', '6', '50,50', 'I', '30');          // sides, center, I/C, radius
cad.cmd('ELLIPSE', '50,50', '100,50', '0.5');         // center, major-end, ratio ≤ 1
cad.cmd('TEXT',   '10,10', '5', '0', 'Hello');        // pt, height, ROTATION, string
cad.cmd('MTEXT',  '10,10', '90,60', 'Multi-line');    // 2 corners, string

// Modify — these select first. Pick with 'L' (last) or 'ALL', close the
// selection with cad.confirm(), then answer the rest with cad.input().
cad.cmd('MOVE',   'L'); cad.confirm(); cad.input('0,0'); cad.input('50,50');
cad.cmd('COPY',   'L'); cad.confirm(); cad.input('0,0'); cad.input('100,0'); cad.confirm();
cad.cmd('ROTATE', 'L'); cad.confirm(); cad.input('0,0'); cad.input('45');
cad.cmd('SCALE',  'L'); cad.confirm(); cad.input('0,0'); cad.input('2');
cad.cmd('MIRROR', 'L'); cad.confirm(); cad.input('0,0'); cad.input('0,100'); cad.input('N');
cad.cmd('ERASE',  'L'); cad.confirm();
cad.cmd('OFFSET', 'L'); cad.confirm(); cad.input('5');        // or a point on the side
cad.cmd('HATCH',  'L'); cad.confirm(); cad.input('ANSI31');   // boundary must be closed

// Dimensions
cad.cmd('DIMLINEAR', '0,0', '100,0', '50,-15');
cad.dim.radius('50,50', 30, '85,80');
cad.dim.angular('0,0', '100,0', '0,100', '40,40');

// History
cad.history.beginGroup(); /* ... */ cad.history.endGroup();
cad.history.undo();

// Inspect
cad.doc.entities();
cad.doc.summary();

Warnings

run returns a warnings array (also printed to stderr as [warn] …) naming every command that ended without drawing:

{"ok":true,"output":"out/plan.dxf","entityCount":3,
 "warnings":["TEXT: cancelled by the next command while still waiting for input after 3 argument(s) — nothing was drawn. Check the argument list for this command."]}

An agent should treat a non-empty warnings as a failed script and fix the argument list — ok:true only means the file was written.

Full reference: see docs/ai/SYSTEM_PROMPT.md in the parent repo.

Architecture

┌─ Host (Node.js)
│  bin/pure-cad.js → src/index.js → src/commands/{run,query,export,new}.js
│    └─ fs.readFileSync / fs.writeFileSync (file I/O)
│    └─ src/wasm-parse.js → io/pkg-node WASM  ← DWG parsing (host-side, Rust)
│       ↓  DWG: parseResult JSON injected   ·   DXF: base64 bytes
└─ Guest VM (QuickJS-WASM, sandboxed)
   └─ dist/core.bundle.js
      ├─ CadDocument, HistoryManager, CommandBridge
      ├─ commands/* (LINE, CIRCLE, MOVE, DIM*, ...)
      └─ io/DxfReader, DxfWriter, DwgWriter (pure JS) — no JS DWG reader

No source code escape: Core JS lives inside the WASM-backed VM. CLI binary contains only the bundle and a thin host shim.

Source protection (W-5)

The DWG reverse-engineering algorithm (multi-version read: 2004+ LZ77, 2007+ Reed–Solomon, bitstream decode, handle resolution) is not shipped as plaintext. DWG files are parsed host-side by the compiled Rust WASM parser (io/pkg-node), and only the resulting parseResult (JSON) is injected into the VM. The Core bundle keeps the JS DXF reader (a public, documented format) and the DWG/DXF writers, but carries no JS DWG reader.

Two build-time gates enforce this (npm run build):

• build/build-core.mjs — an esbuild guard that fails the build if any DWG-reader module (DwgReader, io/internal/{entities,tables,structure,compression,header}, ObjectMap/HandleResolver, BitReader, LcgXorMask/ReedSolomon) is re-imported into the bundle. Writer shared primitives (BitWriter, Crc, EntityCommon) stay allowed.
• build/guard-bundle.mjs — greps the built bundle for reader symbols and fails if any leak.

Scope (honest boundary): this seals the reader algorithm. R2000 write knowledge remains reconstructible from the bundled DwgWriter until that writer is ported to Rust (roadmap item T-1). Loud-fail: a DWG the Rust parser cannot read surfaces WASM_PARSE_FAILED — there is no silent JS fallback.

Requires the local Rust build io/pkg-node (npm run io:build:node at the repo root) present alongside the package during DWG operations.

License

UNLICENSED — internal use only.