# This script configures IIS application pool and app.
# example usage:
# PS> init-server.ps1 -AppName MyApp -TargetComputers machine1,machine2 -PSSessionUser $(PSSessionUser) -PSSessionPassword $(PSSessionPassword) -AppPoolUser $(AppPoolUser) -AppPoolPassword $(AppPoolPassword)

param(
	[Parameter(Mandatory=$true)][string]$AppName,
	[string]$TargetComputers,
	[string]$Username,
	[string]$PSSessionUser,
	[string]$PSSessionPassword,
	[string]$AppPoolUser,
	[string]$AppPoolPassword,
	[switch]$Cleanup,
	[switch]$Show)

$script = {
	param(
		$AppName,
		$AppPoolUser,
		$AppPoolPassword,
		$Cleanup,
		$Show
	)

	$apppool = $AppName
	$site = 'Default Web Site'
	$path = "/Apps/$AppName"
	$app = "$site$path"
	$physicalPath = "C:\Applications\Apps\$AppName"

	$appcmd = [System.Environment]::ExpandEnvironmentVariables("%systemroot%\system32\inetsrv\AppCmd.exe")

	$appPoolExists = (&$appcmd list apppool /name:$apppool) -ne $null
	if ($appPoolExists -eq $false)
	{
		&$appcmd add apppool /name:$apppool `
			/startMode:AlwaysRunning `
			/autoStart:true `
			/managedRuntimeVersion:'v4.0' `
			/processModel.identityType:SpecificUser `
			/processModel.userName:$AppPoolUser `
			/processModel.password:$AppPoolPassword
	}
	else
	{
		&$appcmd set apppool $apppool `
			/startMode:AlwaysRunning `
			/autoStart:true `
			/managedRuntimeVersion:'v4.0' `
			/processModel.identityType:SpecificUser `
			/processModel.userName:$AppPoolUser `
			/processModel.password:$AppPoolPassword
	}

	$appExists = (&$appcmd list app /path:$path /site.name:$site) -ne $null
	if ($appExists -eq $false)
	{
		&$appcmd add app `
			/site.name:$site `
			/path:$path `
			/physicalPath:$physicalPath `
			/applicationPool:$apppool
	}
	else
	{
		&$appcmd set app $app `
			/site.name:$site `
			/path:$path `
			/applicationPool:$apppool
	}

	if ($Cleanup -eq $true)
	{
		&$appcmd delete apppool $apppool
		&$appcmd delete app $app
	}

	if ($Show -eq $true) {
		&$appcmd list apppool $apppool /config
		&$appcmd list app $app /config
	}
}

$pw = ConvertTo-SecureString $PSSessionPassword -AsPlainText -Force
$credential = new-object -typename System.Management.Automation.PSCredential -argumentlist $PSSessionUser, $pw

foreach ($computer in $TargetComputers.Split(@(','), [System.StringSplitOptions]::RemoveEmptyEntries))
{
	Write-Host "Configuring $AppName on $($computer.Trim())" -BackgroundColor Black -ForegroundColor Green

	$session = New-PSSession -ComputerName $computer -Credential $credential

	Invoke-Command -Session $session `
		-ArgumentList ($AppName, $AppPoolUser, $AppPoolPassword, $Cleanup, $Show) `
		-ScriptBlock $script

	Remove-PSSession $session
}