#!/usr/bin/env python3
"""Locate REMAINING OB from the HUD value instead of from kill events.

The correlation route works but needs marked-fighter kills, and the pilot gets
about two per five minutes (remaining-ob-hunt.md). The HUD already shows the
number, and ob_read.py already reads it, so match the displayed value against
memory directly -- no kills required.

Each reading intersects: keep heap words equal to the value the HUD shows at
that moment. A second reading at a DIFFERENT value collapses the set hard; even
repeated readings at the same value help, since unrelated words drift.
"""
import os, sys, time, subprocess, collections
sys.path.insert(0, __file__.rsplit('/', 1)[0])
import gmem, gworld
import numpy as np
import ob_read

LO, HI = 0xBD000000, 0xBE000000
SHOT = '/tmp/ob_hud.png'

def region(fd):
    lo, hi = gmem.va_to_off(LO), gmem.va_to_off(HI)
    out, pos = bytearray(), lo
    while pos < hi:
        n = min(1 << 24, hi - pos); out += os.pread(fd, n, pos); pos += n
    return np.frombuffer(bytes(out), dtype='>u4'), lo

def hud_value():
    subprocess.run(['screenshot', SHOT], capture_output=True, timeout=60)
    try:
        txt, scores = ob_read.read(SHOT)
    except Exception as e:
        return None, str(e)
    t = (txt or '').strip()
    if not t.isdigit(): return None, 'unreadable %r' % txt
    return int(t), 'scores %s' % (scores,)   # ob_read returns tuples, not floats

def main():
    secs  = int(sys.argv[1]) if len(sys.argv) > 1 else 240
    every = int(sys.argv[2]) if len(sys.argv) > 2 else 25
    w = gworld.World(); fd = w.fd
    cand = None; base = None; seen = []
    t0 = time.time()
    while time.time() - t0 < secs:
        v, note = hud_value()
        el = round(time.time() - t0)
        if v is None:
            print('  t=%4ds  HUD unreadable (%s)' % (el, note), flush=True)
        else:
            r, base = region(fd)
            hit = set(np.nonzero(r == v)[0].tolist())
            cand = hit if cand is None else (cand & hit)
            seen.append(v)
            print('  t=%4ds  HUD=%-4d words==%d: %-8d -> candidates %d  (%s)'
                  % (el, v, v, len(hit), len(cand), note), flush=True)
            if len(cand) <= 40 and len(set(seen)) >= 2:
                break
        time.sleep(every)
    print('\nHUD values seen: %s' % sorted(set(seen)))
    if cand and base is not None:
        print('candidates: %d' % len(cand))
        for i in sorted(cand)[:20]:
            va = gmem.primary_va(base + i * 4)
            print('   va %s' % (('%#010x' % va) if va else '?'))
    else:
        print('no candidates (HUD never read, or value never matched a u32)')
    return 0

if __name__ == '__main__':
    sys.exit(main())