# E01-S04: build and verify display/clock behavior in both x128 modes.
[CmdletBinding()]
param(
    [int]$RemotePort = 6510,
    [int]$LimitCycles = 30000000
)

$ErrorActionPreference = "Stop"
$project = Split-Path $PSScriptRoot -Parent
$build = Join-Path $project "build"
$program = Join-Path $build "display-clock.prg"
$traceCommands = Join-Path $project "monitor\display-clock-trace.txt"
$x128 = "C:\Program Files\GTK3VICE-3.10-win64\bin\x128.exe"

& (Join-Path $PSScriptRoot "build-display-clock.ps1")
if ($LASTEXITCODE -ne 0) { throw "display/clock build failed" }
if (-not (Test-Path -LiteralPath $x128)) { throw "x128.exe not found at $x128" }

function Quote-Arg([string]$value) {
    if ($value -ne "" -and $value -notmatch '[\s"]') { return $value }
    $escaped = $value -replace '(\\*)"', '$1$1\"'
    $escaped = $escaped -replace '(\\+)$', '$1$1'
    return '"' + $escaped + '"'
}

function Start-X128([string[]]$arguments) {
    $psi = [Diagnostics.ProcessStartInfo]::new()
    $psi.FileName = $x128
    $psi.Arguments = ($arguments | ForEach-Object { Quote-Arg $_ }) -join ' '
    $psi.UseShellExecute = $true
    $psi.WindowStyle = [Diagnostics.ProcessWindowStyle]::Hidden
    return [Diagnostics.Process]::Start($psi)
}

function Invoke-Screenshot([string]$mode) {
    $screenshot = Join-Path $build ("display-clock-{0}.png" -f $mode)
    if (Test-Path -LiteralPath $screenshot) {
        Remove-Item -LiteralPath $screenshot -Force
    }

    $captureOption = if ($mode -eq '40') { '-exitscreenshotvicii' } else { '-exitscreenshot' }
    $process = Start-X128 @(
        ("-{0}col" -f $mode),
        '-autostart', $program,
        '-autostart-warp', '-warp',
        '-sounddev', 'dummy',
        '-limitcycles', "$LimitCycles",
        $captureOption, $screenshot
    )
    $process.WaitForExit()

    if (-not (Test-Path -LiteralPath $screenshot)) {
        throw "x128 did not create $screenshot"
    }
    if ((Get-Item -LiteralPath $screenshot).Length -lt 1000) {
        throw "$screenshot is unexpectedly small"
    }
    Write-Host ("{0}-column screenshot: {1}" -f $mode, $screenshot)
}

function Invoke-MonitorVerification(
    [string]$mode,
    [byte]$expectedResult,
    [byte]$expectedMode,
    [byte]$expectedFast
) {
    $transcript = Join-Path $build ("display-clock-{0}-remote.txt" -f $mode)
    foreach ($path in @($transcript)) {
        if (Test-Path -LiteralPath $path) { Remove-Item -LiteralPath $path -Force }
    }

    $process = Start-X128 @(
        ("-{0}col" -f $mode),
        '-autostart', $program,
        '-autostart-warp', '-warp',
        '-sounddev', 'dummy',
        '-moncommands', $traceCommands,
        '-remotemonitor',
        '-remotemonitoraddress', ("ip4://127.0.0.1:{0}" -f $RemotePort)
    )

    $client = $null
    try {
        $deadline = [DateTime]::UtcNow.AddSeconds(10)
        while ([DateTime]::UtcNow -lt $deadline) {
            if ($process.HasExited) { throw "x128 exited before $mode-column verification" }
            try {
                $client = [Net.Sockets.TcpClient]::new()
                $client.Connect('127.0.0.1', $RemotePort)
                break
            } catch {
                if ($client) { $client.Dispose(); $client = $null }
                Start-Sleep -Milliseconds 200
            }
        }
        if (-not $client -or -not $client.Connected) {
            throw "could not connect to the VICE remote monitor"
        }

        Start-Sleep -Seconds 3
        $stream = $client.GetStream()
        $stream.ReadTimeout = 2000
        $writer = [IO.StreamWriter]::new($stream, [Text.Encoding]::ASCII, 1024, $true)
        $writer.NewLine = "`n"
        $writer.AutoFlush = $true
        $writer.WriteLine('m $1d0f $1d14')
        Start-Sleep -Milliseconds 300
        $writer.WriteLine('m $d030 $d030')
        Start-Sleep -Milliseconds 700

        $buffer = New-Object byte[] 8192
        $response = ""
        while ($stream.DataAvailable) {
            $count = $stream.Read($buffer, 0, $buffer.Length)
            if ($count -le 0) { break }
            $response += [Text.Encoding]::ASCII.GetString($buffer, 0, $count)
            Start-Sleep -Milliseconds 50
        }
        [IO.File]::WriteAllText($transcript, $response, [Text.Encoding]::ASCII)

        $expectedBytes = '{0:x2}\s+{1:x2}\s+{2:x2}\s+00\s+5a\s+c3' -f
            $expectedResult, $expectedMode, $expectedFast
        if ($response -notmatch ("(?i)C:1d0f\s+" + $expectedBytes)) {
            throw "$mode-column result block mismatch; response: $response"
        }
        $clockMatch = [regex]::Match($response, '(?i)C:d030\s+([0-9a-f]{2})\b')
        if (-not $clockMatch.Success) {
            throw "$mode-column response did not include `$D030"
        }
        $clockValue = [Convert]::ToByte($clockMatch.Groups[1].Value, 16)
        if (($clockValue -band 0x01) -ne 0) {
            throw "$mode-column fallback left `$D030 speed bit set"
        }

        $writer.WriteLine('q')
        $writer.Dispose()
        $client.Dispose()
        $client = $null
        if (-not $process.WaitForExit(5000)) {
            throw "x128 did not exit after remote-monitor quit"
        }

        # With a remote monitor connected, non-stopping trace messages are
        # delivered in the remote transcript.
        $trace = $response
        if ($trace -notmatch '(?i)1c8c') {
            throw "$mode-column trace did not reach fallback_done"
        }
        if ($mode -eq '40') {
            if ($trace -notmatch '(?i)1c2e') { throw '40-column trace missed its path' }
            if ($trace -match '(?i)1c49') { throw '40-column path entered fast checkpoint' }
        } else {
            if ($trace -notmatch '(?i)1c3d') { throw '80-column trace missed its path' }
            if ($trace -notmatch '(?i)1c49') { throw '80-column trace missed fast checkpoint' }
        }

        Write-Host ("verified {0}-column result `${1:X2}, mode `${2:X2}, fast `${3:X2}, final clock `$00" -f
            $mode, $expectedResult, $expectedMode, $expectedFast)
    } finally {
        if ($client) { $client.Dispose() }
        if ($process -and -not $process.HasExited) {
            $process.Kill()
            $process.WaitForExit()
        }
    }
}

Invoke-Screenshot '40'
Invoke-Screenshot '80'
Invoke-MonitorVerification '40' 0x44 0x00 0x00
Invoke-MonitorVerification '80' 0x85 0x80 0x01

Write-Host 'display/clock probe passed in 40- and 80-column modes'