# `Raxol.Terminal.InlineDriver.CursorReport`
[🔗](https://github.com/DROOdotFOO/raxol/blob/v2.7.0/lib/raxol/terminal/inline_driver/cursor_report.ex#L1)

Pure scanner for a DSR-6 cursor position report (CPR — `CSI Pr ; Pc R`,
the reply a terminal sends to `CSI 6n`) inside a raw tty input stream.

Extracted from `Raxol.Terminal.InlineDriver.probe_cursor/2`'s receive
loop so the byte-boundary contract is unit-testable with zero
process/device setup:

  * **The CPR itself is consumed** — split out of the stream so it can
    never reach `Raxol.Terminal.ANSI.InputParser` (which would decode
    a row-1 reply, `\e[1;<n>R`, as a modified **F3 keypress** — the
    classic DSR/F3 wire collision — and deliver a phantom key event to
    the app).
  * **Every other byte is preserved in arrival order** — real
    keystrokes interleaved with (or split around) the reply are handed
    back for normal dispatch, never dropped (the same leak-free rule
    the T1 capability probe's `{:leak_free, _}` action enforces).
  * **The held-back tail is bounded** — at most 12 bytes (the
    longest possible CPR is `\e[9999;9999R`, 12 bytes) are ever kept
    waiting for a continuation chunk, so a flooding device cannot grow
    the probe buffer: everything already scanned past is flushed
    forward immediately.

The scan is byte-oriented (no `/u` regex, no `String` walking): raw tty
input is untrusted binary and may contain invalid UTF-8, 8-bit C1
controls, or anything else — none of which may crash the scanner.

# `position`

```elixir
@type position() :: {pos_integer(), pos_integer()}
```

1-based `{row, col}` as reported by the terminal.

# `scan`

```elixir
@spec scan(binary()) ::
  {:reply, position(), binary(), binary()} | {:pending, binary(), binary()}
```

Scans `buffer` for a complete CPR.

  * `{:reply, {row, col}, leading, trailing}` — a CPR was found.
    `leading`/`trailing` are the non-CPR bytes before/after it, in
    arrival order, for normal input dispatch. The CPR bytes themselves
    appear in neither.
  * `{:pending, forward, keep}` — no complete CPR yet. `forward` is
    safe to dispatch as ordinary input NOW; `keep` (at most
    12 bytes, possibly empty) is the tail that could still
    be the start of a CPR split across chunks — prepend it to the next
    chunk and scan again (or dispatch it as ordinary input once the
    probe deadline lapses).

A `0` row or column (`\e[0;0R` — not a screen position any 1-based
terminal can report) is rejected as a reply and forwarded as ordinary
input; scanning continues past it.

---

*Consult [api-reference.md](api-reference.md) for complete listing*