# bim-acad — AutoCAD driver for bim-cli

bim-acad drives the headless AutoCAD Core Console (accoreconsole.exe) that ships
with every AutoCAD 2025/2026 install. No GUI, no add-in DLL. Invoke as
`bim acad <verb> <file> [flags]`. Output is JSON on stdout; NDJSON for streaming
verbs. Discover the full schema with `bim describe --json`.

## Requirements

- A local AutoCAD 2025 or 2026 install. `accoreconsole.exe` is auto-discovered
  (highest year first); override with `--console <path>` or `$BIM_ACAD_CONSOLE`.
- Run `bim acad doctor` first to confirm the Core Console is found.

## Constraints (read before scripting exec)

- The Core Console is CORE-ONLY: AutoLISP and .NET (NETLOAD) work, but COM /
  ActiveX `vla-*` functions do NOT ("no function definition").
- In a `.scr`, a SPACE is an ENTER. Multi-word command answers split across
  prompts — pass wildcard patterns or accept defaults with a blank line.
- Use forward slashes in AutoLISP path literals (backslash is an escape char).

## Reading verbs (read-only; safe to batch)

- `bim acad info <file>` — layers, layouts, blocks, model-space entity counts by
  type, and drawing extents. JSON.
- `bim acad extract <file> [--layer L] [--types LINE,CIRCLE] [--limit N]` —
  model-space entities as NDJSON: `{type, layer, handle, point, radius, text,
  name}`. `name` is the block name for INSERTs — group by it to count blocks.
- `bim acad blocks <file>` — block-definition inventory as NDJSON: `{name,
  instances, has_attributes, anonymous, xref, xref_path}`.
- `bim acad attributes <file> [--block PATTERN] [--layout SPACE] [--limit N]` —
  block-reference attributes as NDJSON: `{name, handle, space, insert,
  attributes:{TAG:VALUE}}`. Each `.attributes` map is a field payload for
  `bim pdf form.fill`.
- `bim acad xref list <file>` — external references: `{name, path, type, status}`.

## Output verbs

- `bim acad convert <file> --to dxf|dwg|pdf [--out P] [--version 2000..2018]
  [--layout L] [--paper "ISO A3 (420.00 x 297.00 MM)"] [--orientation
  Landscape|Portrait] [--dry-run] [--yes]` — DWG<->DXF (version-targeted) or print
  to PDF via the built-in `DWG To PDF.pc3` plotter (Extents/Fit; blank paper =
  device default, so any drawing prints). Destructive → supports `--dry-run`/`--yes`.
- `bim acad elements <file>` — emit a PDF·BIM package-v1 `elements.json`
  (`schemaVersion`, `generator`, `source`, `units`, `sheets`, `elements`) built
  from the drawing's blocks + attributes + layouts. This is the metadata for
  `bim pdf package`.

## Maintenance verbs (mutate the drawing; open read-write, save in place or --out)

- `bim acad purge <file> [--out P] [--yes] [--dry-run]` — `-PURGE All` + save;
  reports `bytes_before`/`bytes_after`.
- `bim acad audit <file> [--out P] [--yes] [--dry-run]` — `AUDIT` fix + save;
  reports `errors_found`/`errors_fixed`.
- `bim acad xref detach <file> --name PATTERN | --all [--out P] [--yes]` — detach
  external references. `--name` is a WILDCARD pattern (xref names with spaces
  split), `--all` uses `*`.
- `bim acad xref bind <file> --name PATTERN | --all [--out P] [--yes]` — bind
  references into the drawing. Requires the referenced files to be resolvable
  (alongside the drawing); errors clearly if they are unresolved.

## Escape hatch

- `bim acad exec <file> [--scr FILE] [--lisp FILE] | -` — run an arbitrary
  `.scr`/AutoLISP script against the drawing (script may be piped on stdin).
  Core-only: no COM/`vla-*`.

## DWG → PDF·BIM pipeline

```
bim acad convert  sheet.dwg --to pdf --out sheet.pdf
bim acad elements sheet.dwg > elements.json
bim pdf  package  --file sheet.pdf --metadata elements.json --out sheet.pkg.pdf
bim pdf  bim.validate --file sheet.pkg.pdf
```

The block instances become elements (handle = `id`, block name = `category`,
attributes = `parameters`), layouts become sheets, and INSUNITS becomes units.