#!/usr/bin/env python3
"""Identify the 7 differing 64KB pages and dump per-page summaries."""
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()

PG = 65536
PC_LO, PC_HI = 0x82000000, 0x82A00000
V80 = 0x80000000

print("=== differing 64KB pages ===\n")
for i in range(0, len(canary), PG):
    if not any(canary[i:i+PG]) and not any(ours[i:i+PG]):
        continue
    if canary[i:i+PG] == ours[i:i+PG]:
        continue
    page_addr = V80 + i
    # count differing dwords
    diffs = 0
    pc_diffs_canary = 0
    pc_diffs_ours = 0
    for j in range(0, PG, 4):
        cdw = struct.unpack_from(">I", canary, i+j)[0]
        odw = struct.unpack_from(">I", ours, i+j)[0]
        if cdw != odw:
            diffs += 1
            if PC_LO <= cdw < PC_HI:
                pc_diffs_canary += 1
            if PC_LO <= odw < PC_HI:
                pc_diffs_ours += 1
    cnz = sum(1 for b in canary[i:i+PG] if b != 0)
    onz = sum(1 for b in ours[i:i+PG] if b != 0)
    print(f"page {page_addr:#010x}: {diffs} diff dwords, canary_nz={cnz}, ours_nz={onz}, "
          f"PCs_in_diffs(canary={pc_diffs_canary}, ours={pc_diffs_ours})")

print("\n=== detailed dump: first 64 differing dwords per page ===")
for i in range(0, len(canary), PG):
    if canary[i:i+PG] == ours[i:i+PG]:
        continue
    if not any(canary[i:i+PG]) and not any(ours[i:i+PG]):
        continue
    page_addr = V80 + i
    print(f"\n--- page {page_addr:#010x} ---")
    shown = 0
    for j in range(0, PG, 4):
        cdw = struct.unpack_from(">I", canary, i+j)[0]
        odw = struct.unpack_from(">I", ours, i+j)[0]
        if cdw != odw:
            addr = V80 + i + j
            shown += 1
            print(f"  +{j:#06x}={addr:#010x}: canary={cdw:#010x}  ours={odw:#010x}")
            if shown >= 64:
                # report total remaining
                remaining = sum(1 for k in range(j+4, PG, 4)
                                if struct.unpack_from(">I", canary, i+k)[0] !=
                                   struct.unpack_from(">I", ours, i+k)[0])
                print(f"  ... and {remaining} more on this page")
                break