#!/usr/bin/env python3
"""Pin the world-unit / displayed-speed ratio at the one unambiguous point.

At neutral throttle the HUD reads exactly `CruisingVelocity` (350 for the player),
so no digit-reading is needed to know the game's own number — only a clean
measurement of how far the craft actually travels in world units.

Cleanliness matters more than length here: earlier ratios (1.19–1.29) were sampled
in a firefight where the craft is shoved around, and with a stick input the path is
longer than the displacement. So this flies straight, holds neutral throttle, and
takes ONE long displacement over a 20 s window, plus screenshots at both ends to
confirm the HUD never moved off 350.

Usage: cruise_ratio.py [window_s]
"""
import math, os, subprocess, sys, time
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
import speed_law

CRUISE = 350.0          # UN_f001_TCAF_DeltaSaber_T_Player CruisingVelocity

def pad(*a):
    subprocess.run(["vgamepad", *a], capture_output=True)

def shot(name):
    subprocess.run(["screenshot", f"/sylph-home/re/shots/{name}.png"], capture_output=True)

def main():
    win = float(sys.argv[1]) if len(sys.argv) > 1 else 20.0
    w, off, nm = speed_law.find_player()
    if not w:
        sys.exit("player entity not found after retries")
    print(f"# locked on {nm}")
    pad("reset")
    pad("trig", "RT", "0.0"); pad("trig", "LT", "0.0")
    time.sleep(6.0)                     # settle at cruise, sticks centred
    shot("cruise_start")
    p0, t0 = speed_law.pos_at(w.fd, off), time.time()
    samples = [(0.0, *p0)]
    while time.time() - t0 < win:
        time.sleep(0.25)
        samples.append((round(time.time() - t0, 3), *speed_law.pos_at(w.fd, off)))
    shot("cruise_end")
    p1, t1 = samples[-1][1:], samples[-1][0]
    disp = math.dist(p0, p1)
    path = sum(math.dist(samples[i][1:], samples[i + 1][1:]) for i in range(len(samples) - 1))
    print(f"# window {t1:.1f}s   displacement {disp:8.0f}   path {path:8.0f}   "
          f"straightness {disp / path:.3f}")
    print(f"# speed by displacement {disp / t1:7.1f}/s   by path {path / t1:7.1f}/s")
    print(f"# ratio vs HUD {CRUISE:.0f}:  displacement {disp / t1 / CRUISE:.3f}   path {path / t1 / CRUISE:.3f}")

if __name__ == "__main__":
    main()