"""Show what the pad is doing, with no dataflow and nothing attached to it.

`dora-joy-probe` opens the gamepad and prints, live: every axis SDL reports and
every button it sees pressed, by index.

It exists because a consumer's axis and button indices are almost always SDL's
documented layout rather than an observed one, and a pad that numbers its
controls differently is otherwise discovered by watching a real machine move the
wrong way. Push one control at a time and read off the index it moves.

This shows the reading and nothing else — it has no idea what any index is *for*,
which is the same thing that makes this node reusable.

Nothing here can move anything. There is no dora node and no connection to
anything; this only reads.
"""

import argparse
import time

from dora_joy.config import Config
from dora_joy.gamepad import Gamepad

CLEAR = "\033[H\033[J"


def bar(value: float, width: int = 21) -> str:
    """Draw a centred bar for a value between -1 and 1.

    Seeing the bar sit off-centre with the stick released is how a worn pad
    announces itself, which is most of the point of looking at raw numbers.
    """
    middle = width // 2
    position = middle + round(max(-1.0, min(1.0, value)) * middle)
    cells = ["-"] * width
    cells[middle] = "|"
    cells[position] = "#"
    return "".join(cells)


def render(sample, config: Config) -> str:
    """Build the whole display for one reading."""
    lines = ["dora-joy probe — Ctrl-C to stop", ""]

    if not sample.present:
        lines += [
            "  no gamepad found.",
            "",
            f"  looking for joystick index {config.joystick_index};",
            "  plug one in and this will pick it up.",
        ]
        return "\n".join(lines)

    lines.append(f"  axes ({len(sample.axes)} reported)")
    for index, value in enumerate(sample.axes):
        lines.append(f"    {index}  {value:+.3f}  {bar(value)}")

    held = [str(index) for index, down in enumerate(sample.buttons) if down]
    lines += ["", f"  buttons ({len(sample.buttons)} reported)", f"    {', '.join(held) or 'none pressed'}"]
    lines += ["", "  push one control at a time and note the index it moves."]
    return "\n".join(lines)


def main() -> None:
    """Open the pad and print what it is doing until interrupted."""
    parser = argparse.ArgumentParser(description="Show what the gamepad is doing. Moves nothing.")
    parser.add_argument("--hz", type=float, default=10.0, help="Redraw rate. Defaults to 10.")
    args = parser.parse_args()

    config = Config.from_env()
    gamepad = Gamepad(config.joystick_index)
    gamepad.start()

    try:
        while True:
            print(CLEAR + render(gamepad.read(), config), flush=True)
            time.sleep(1.0 / args.hz)
    except KeyboardInterrupt:
        print()
    finally:
        gamepad.shutdown()


if __name__ == "__main__":
    main()