# dsh-line-select · Line-Range Selection Plugin

A DeepSeek Harness Web GUI plugin: browse workspace files, preview code with line numbers, **visually select a line range**, and write a `@path:start-end` reference into the composer — when the message is sent, the agent automatically receives the exact selected lines and can modify precisely that range (e.g. lines 10–50).

## Features

- **File-tree browser**: a 「⛶ 行选区」 button above the composer opens a panel that browses the workspace directory (dot-files skipped, directories first)
- **Numbered preview**: click a file to open a read-only view with line numbers (auto light/dark theme)
- **Line-range selection**: click a line number to set the start, click again to set the end (either order; range only expands), the selection is highlighted
- **Write to composer**: one click appends `@src/app.ts:10-50 ` to the current draft; the Host expands that reference into an injected `<workspace-selection>` at `agent/pre-step`, so the agent sees the source lines without reading the file itself
- **Select file (whole-file reference)**: the 「选中文件」 button writes `@src/app.ts ` into the draft, letting the agent read the whole file with its `read` tool (without stuffing large contents into context)
- **Hand-written references work too**: type `@src/app.ts:10-50`, `@src/app.ts:10` (single line), or `@src/app.ts` (whole file) directly — spaces in file names are supported (e.g. `@新建 文本文档.md:3-8`)

## Install

```sh
dsh plugin --profile web add <this directory or tarball path>
```

Restart `dsh web` after installation.

Uninstall:

```sh
dsh plugin --profile web remove dsh-line-select
```

## How it works

| Layer | Description |
|---|---|
| Host (`lib/index.js`) | `lineSelect` Typert Remote service (strict manifest): `list` lists a directory, `read` reads a file with line numbers; `agent/pre-step` scans `@path:start-end` tokens in user messages, reads the range, and injects `<workspace-selection path="…" start-line="…" end-line="…"><line n="…">…</line></workspace-selection>` |
| Client (`lib/client.js`) | `conversation.input.dock` entry: panel UI + selection interaction; writes the draft through the official `inputActions.setDraft` seam |

## Security

- Every path is confined to the session cwd (absolute paths, drive letters, and `..` traversal are rejected)
- Read-only: never writes to disk, never executes file contents
- Limits: 1 MB per file (head-only beyond that), 800 preview lines, 400 injected lines per reference
- Zero third-party runtime dependencies (only `@deepseek-ai/dsh-typert-protocol` and `@deepseek-ai/dsh-llm` peer deps, provided by the DSH profile)

## Tests

```sh
# From the DSH checkout, link its node_modules once for module resolution:
#   New-Item -ItemType Junction -Path node_modules -Target <dsh checkout>/node_modules
node test/smoke.mjs
```

## License

MIT