#!/usr/bin/env python3
"""Sanity-check the v80 captures: byte-counts, equal-dword counts, raw PC counts."""
import struct
import os

here = os.path.dirname(os.path.abspath(__file__))
canary = open(os.path.join(here, "canary-v80.bin"), "rb").read()
ours = open(os.path.join(here, "ours-v80.bin"), "rb").read()
print(f"canary len: {len(canary)}")
print(f"ours len:   {len(ours)}")

c_nonzero = sum(1 for b in canary if b != 0)
o_nonzero = sum(1 for b in ours if b != 0)
print(f"canary non-zero bytes: {c_nonzero} ({c_nonzero/len(canary)*100:.2f}%)")
print(f"ours non-zero bytes:   {o_nonzero} ({o_nonzero/len(ours)*100:.2f}%)")

# Sliding 64KB window: byte-equal pages
PG = 65536
c_pgs = sum(1 for i in range(0, len(canary), PG) if any(canary[i:i+PG]))
o_pgs = sum(1 for i in range(0, len(ours), PG) if any(ours[i:i+PG]))
print(f"canary 64K-pages with any non-zero: {c_pgs}")
print(f"ours   64K-pages with any non-zero: {o_pgs}")

# Compare per 64K page where canary has data:
both, only_c, only_o, neither, equal = 0, 0, 0, 0, 0
for i in range(0, len(canary), PG):
    cnz = any(canary[i:i+PG])
    onz = any(ours[i:i+PG])
    if cnz and onz:
        both += 1
        if canary[i:i+PG] == ours[i:i+PG]:
            equal += 1
    elif cnz:
        only_c += 1
    elif onz:
        only_o += 1
    else:
        neither += 1
print(f"64K-page comparison: both_have_data={both}  byte_equal_among_those={equal}  canary_only={only_c}  ours_only={only_o}")

# Count PC-range dwords on each side overall
PC_LO, PC_HI = 0x82000000, 0x82A00000
c_pc = sum(1 for i in range(0, len(canary), 4) if PC_LO <= struct.unpack_from(">I", canary, i)[0] < PC_HI)
o_pc = sum(1 for i in range(0, len(ours), 4) if PC_LO <= struct.unpack_from(">I", ours, i)[0] < PC_HI)
print(f"canary dwords in PC range: {c_pc}")
print(f"ours   dwords in PC range: {o_pc}")