"""Reverse-thrust verification: hold W to build throttle, then hold LALT and
confirm the mapper flips to reverse (speedDemand goes negative).

Injects keys with keybd_event into a btl4 launched with BT_KEY_NOFOCUS=1, so it
does not need window focus.  Kills ONLY the PID it spawned.
"""
import ctypes
import os
import re
import subprocess
import sys
import time

VK_W = 0x57
VK_LMENU = 0xA4          # left Alt
KEYEVENTF_KEYUP = 0x0002

user32 = ctypes.windll.user32

def hold(vk, seconds):
    user32.keybd_event(vk, 0, 0, 0)
    time.sleep(seconds)

def release(vk):
    user32.keybd_event(vk, 0, KEYEVENTF_KEYUP, 0)

CONTENT = r"C:\git\bt411\content"
EXE = r"C:\git\bt411\build\Release\btl4.exe"
LOG = r"C:\git\bt411\scratchpad_rev.log"

if os.path.exists(LOG):
    os.remove(LOG)

env = dict(os.environ)
env.update({
    "BT_START_INSIDE": "1",
    "BT_KEY_NOFOCUS": "1",
    "BT_MPPR_TRACE": "1",       # [mppr-c] thr= rev= -> dmd=
    "BT_PAD_LOG": "1",          # [padwrite] reverse button
    "BT_LOG": LOG,
})
proc = subprocess.Popen([EXE, "-egg", "LAST.EGG"], cwd=CONTENT, env=env)
print("spawned pid", proc.pid)

try:
    # wait for the mission to be running (the trace only prints in-mission)
    deadline = time.time() + 180
    while time.time() < deadline:
        if os.path.exists(LOG):
            txt = open(LOG, errors="replace").read()
            if "[mppr-c]" in txt:
                break
        time.sleep(2)
    else:
        print("FAIL: never reached the mapper trace")
        sys.exit(1)

    # 1) throttle up with W for 3s, no Alt -> expect rev=0, dmd > 0
    hold(VK_W, 6.0)
    release(VK_W)
    time.sleep(1.5)
    mark = len(open(LOG, errors="replace").read())

    # 2) now hold LALT for 4s -> expect rev=1 and dmd < 0
    hold(VK_LMENU, 5.0)
    release(VK_LMENU)
    time.sleep(1.5)

    txt = open(LOG, errors="replace").read()
    before = txt[:mark]
    during = txt[mark:]

    def rows(chunk):
        return re.findall(r"\[mppr-c\] thr=([-\d.]+) rev=(\d+).*?dmd=([-\d.]+)", chunk)

    b = rows(before)
    d = rows(during)
    print("\n--- forward phase (last 3 samples):", b[-3:])
    print("--- alt-held phase (samples):      ", d[:6])
    print("--- [padwrite] lines:", re.findall(r"\[padwrite\] reverse button.*", txt)[:4])

    fwd_ok = any(int(r[1]) == 0 and float(r[2]) > 0.5 for r in b)
    rev_ok = any(int(r[1]) == 1 and float(r[2]) < -0.5 for r in d)
    print("\nforward (rev=0, dmd>0): %s" % ("PASS" if fwd_ok else "FAIL"))
    print("reverse (rev=1, dmd<0): %s" % ("PASS" if rev_ok else "FAIL"))
finally:
    proc.terminate()
    print("killed", proc.pid)