param(
    [string]$OutputPath = "$(Join-Path $PSScriptRoot 'applicationhost.config')",
    [string]$BaseConfigPath = "$env:ProgramFiles\IIS Express\AppServer\applicationhost.config",
    [string]$SiteName = "AspClassicPublicSite",
    [string]$PhysicalPath = "H:\AI - ASP - Classic\Public",
    [string]$BindingInformation = "*:8080:localhost"
)

if (-not (Test-Path -LiteralPath $BaseConfigPath)) {
    $BaseConfigPath = "$env:ProgramFiles(x86)\IIS Express\AppServer\applicationhost.config"
}

if (-not (Test-Path -LiteralPath $BaseConfigPath)) {
    Write-Error "IIS Express base applicationhost.config not found."
    exit 1
}

[xml]$xml = Get-Content -LiteralPath $BaseConfigPath

$sitesNode = $xml.configuration.'system.applicationHost'.sites
if (-not $sitesNode) {
    Write-Error "Base config does not contain system.applicationHost/sites."
    exit 1
}

$existingSite = $sitesNode.site | Where-Object { $_.name -eq $SiteName }
if ($existingSite) {
    [void]$sitesNode.RemoveChild($existingSite)
}

$siteIds = @($sitesNode.site | ForEach-Object { [int]$_.id })
$nextId = if ($siteIds.Count -gt 0) { ($siteIds | Measure-Object -Maximum).Maximum + 1 } else { 1 }

$site = $xml.CreateElement('site')
$site.SetAttribute('name', $SiteName)
$site.SetAttribute('id', [string]$nextId)
$site.SetAttribute('serverAutoStart', 'true')

$application = $xml.CreateElement('application')
$application.SetAttribute('path', '/')
$application.SetAttribute('applicationPool', 'Clr4IntegratedAppPool')

$virtualDirectory = $xml.CreateElement('virtualDirectory')
$virtualDirectory.SetAttribute('path', '/')
$virtualDirectory.SetAttribute('physicalPath', $PhysicalPath)
[void]$application.AppendChild($virtualDirectory)

$bindings = $xml.CreateElement('bindings')
$binding = $xml.CreateElement('binding')
$binding.SetAttribute('protocol', 'http')
$binding.SetAttribute('bindingInformation', $BindingInformation)
[void]$bindings.AppendChild($binding)

[void]$site.AppendChild($application)
[void]$site.AppendChild($bindings)
[void]$sitesNode.AppendChild($site)

$oldLocation = @($xml.configuration.location | Where-Object { $_.path -eq $SiteName })
foreach ($node in $oldLocation) {
    [void]$xml.configuration.RemoveChild($node)
}

$location = $xml.CreateElement('location')
$location.SetAttribute('path', $SiteName)

$systemWebServer = $xml.CreateElement('system.webServer')

$directoryBrowse = $xml.CreateElement('directoryBrowse')
$directoryBrowse.SetAttribute('enabled', 'false')

$asp = $xml.CreateElement('asp')
$asp.SetAttribute('scriptErrorSentToBrowser', 'true')
$asp.SetAttribute('enableParentPaths', 'true')
$limits = $xml.CreateElement('limits')
$limits.SetAttribute('scriptTimeout', '00:10:00')
[void]$asp.AppendChild($limits)

[void]$systemWebServer.AppendChild($directoryBrowse)
[void]$systemWebServer.AppendChild($asp)
[void]$location.AppendChild($systemWebServer)
[void]$xml.configuration.AppendChild($location)

$xml.Save($OutputPath)
Write-Host "Generated IIS Express config at $OutputPath"