[Console]::OutputEncoding = [Text.Encoding]::UTF8
$cap = "$env:TEMP\opencode\sym_startup.pcap"
$ts = "C:\Program Files\Wireshark\tshark.exe"
$tpl = (Get-Content "C:\Users\tonycao\work\light\enet-validator\samples\announce_686.hex" -Raw).Trim() -replace '\s',''
# 取两帧 live announce (不同时刻)
$anns = @(& $ts -r $cap -Y "udp.length==652" -T fields -e frame.time_relative -e udp.payload 2>$null | Select-Object -First 2)
$h0 = ($anns[0] -split "`t")[1]; $t0 = ($anns[0] -split "`t")[0]
$h1 = ($anns[1] -split "`t")[1]; $t1 = ($anns[1] -split "`t")[0]
Write-Host ("template len=" + $tpl.Length/2 + "  live len=" + $h0.Length/2)
Write-Host ""
Write-Host "=== template vs liveA(t=$t0) 差异区域 ==="
$n = [Math]::Min($tpl.Length, $h0.Length)
$regions = @()
for ($i = 0; $i -lt $n; $i += 2) {
    if ($tpl.Substring($i,2) -ne $h0.Substring($i,2)) {
        $off = $i/2
        if ($regions.Count -eq 0 -or ($off - $regions[$regions.Count-1][1]) -gt 4) {
            [void]$regions.Add(@($off, $off))
        } else { $regions[$regions.Count-1][1] = $off }
    }
}
foreach ($r in $regions) {
    $s = [Math]::Max(0, $r[0]-3); $e = [Math]::Min($tpl.Length/2-1, $r[1]+3)
    $st=''; $sl=''; $sr=''
    for ($i=$s; $i -le $e; $i++) {
        $st += $tpl.Substring(2*$i,2)
        $sl += $h0.Substring(2*$i,2)
        if ($i -le $h1.Length/2-1) { $sr += $h1.Substring(2*$i,2) } else { $sr += '??' }
    }
    Write-Host ("0x{0:x4}-0x{1:x4}: tpl={2}  liveA={3}  liveB={4}" -f $s, $e, $st, $sl, $sr)
}
# liveA vs liveB (两帧实时宣告间的差异 = 每次宣告都变的字段)
Write-Host ""
Write-Host "=== liveA(t=$t0) vs liveB(t=$t1) 差异 (每次宣告变化的字段) ==="
$d2 = @()
for ($i = 0; $i -lt $n; $i += 2) {
    if ($h0.Substring($i,2) -ne $h1.Substring($i,2)) {
        $off = $i/2
        if ($d2.Count -eq 0 -or ($off - $d2[$d2.Count-1][1]) -gt 4) { [void]$d2.Add(@($off,$off)) } else { $d2[$d2.Count-1][1] = $off }
    }
}
foreach ($r in $d2) {
    $s = [Math]::Max(0, $r[0]-3); $e = [Math]::Min($h0.Length/2-1, $r[1]+3)
    $sl=''; $sr=''
    for ($i=$s; $i -le $e; $i++) { $sl += $h0.Substring(2*$i,2); $sr += $h1.Substring(2*$i,2) }
    Write-Host ("0x{0:x4}-0x{1:x4}: A={2}  B={3}" -f $s, $e, $sl, $sr)
}
Set-Content -Encoding ascii "$env:TEMP\opencode\announce_live.hex" $h0
Write-Host "saved: announce_live.hex"