MAME installation updater

update-mame.ps1

if (-not (Get-Command -Name '7z.exe' -CommandType Application)) {
    Write-Warning '7z.exe not found'
    return
}

$output = ./mame.exe -version
# e.g. 0.275 (mame0275)
if ($output -notmatch '(?<friendly>\d+\.\d+) \((?<version>.+)\)') {
    Write-Warning 'Unable to determine local MAME version. Expecting MAME.exe in current folder.'
    return
}

$localMameFriendlyVer = $matches['friendly'] # e.g. '0.276'
$localMameVer = $matches['version'] # e.g. 'mame0276'

'Checking for update ...'
$response = (Invoke-WebRequest -Uri 'https://www.mamedev.org/release.php').Content
if ($response -notmatch '<a href="(?<url>https://github.com/mamedev/mame/releases/download)/(?<version>mame\d+)/(?<binary>mame\d+b_64bit.exe)">mame\d+b_64bit\.exe</a>') {
    Write-Warning 'Unable to determine remote MAME version'
    return
}

$url = $matches['url']
$remoteMameVer = $matches['version']
$binary = $matches['binary']

if ($localMameVer -eq $remoteMameVer) {
    "Local MAME ($localMameFriendlyVer) is up to date."
    return
}

$tempFile = New-TemporaryFile
"Downloading $remoteMameVer to $tempFile ..."
Invoke-WebRequest -Uri "$url/$remoteMameVer/$binary" -OutFile $tempFile

$mamePath = (Get-Location).Path
"Extracting file to $mamePath ..."
Start-Process -Wait -NoNewWindow -FilePath '7z.exe' -ArgumentList 'x', '-bso0', '-y', "-o$mamePath", $tempFile

'Removing temporary file ...'
Remove-Item -LiteralPath $tempFile