"""The wire shapes this node publishes.

Declared, never inferred. pyarrow reads `{"value": None}` as `null` and
`{"value": 1.0}` as `double`, so an inferred `command` would change the type of
its port depending on which verb was pressed — `stop` and `freedrive` would not
agree. The same hazard that makes an unplugged gamepad retype a `joy` port.

dora 1.0 has no standard type for either of these, so these structs and the
manifest that describes them are the whole contract a consumer gets.
"""

import pyarrow as pa

# A velocity, in SI. Metres per second and radians per second, in the frame
# named by `frame` — the units a robot node should consume, and the same ones a
# UR or MoveIt would take.
TWIST = pa.struct(
    [
        ("linear", pa.list_(pa.float64())),
        ("angular", pa.list_(pa.float64())),
        ("frame", pa.string()),
    ]
)

# One discrete thing to do. `action` is a robot-agnostic verb; `value` carries
# its argument where it has one and is null otherwise.
COMMAND = pa.struct([("action", pa.string()), ("value", pa.float64())])

# `dora-ulite6`'s velocity, in mm/s and deg/s. Deprecated along with the `jog`
# port it goes out on.
JOG = pa.struct([("velocity", pa.list_(pa.float64()))])


def pack_twist(twist: dict) -> pa.Array:
    """Build one `twist` message."""
    return pa.array([twist], type=TWIST)


def pack_command(action: str, value: float | None) -> pa.Array:
    """Build one `command` message."""
    return pa.array([{"action": action, "value": value}], type=COMMAND)


def pack_jog(velocity: list[float]) -> pa.Array:
    """Build one deprecated `jog` message."""
    return pa.array([{"velocity": [float(v) for v in velocity]}], type=JOG)