#Requires -Version 2.0

## Set the name of this module
$ModuleName = "PSModule"

## Define base URL for updating modules and resources
$BaseURL = "https://dev.emberkom.com/emberkom/management-scripts/raw/branch/master/${ModuleName}"

## Set the path to this module
$ModulePath = "${Env:MSPDir}\Scripts\${ModuleName}"

## Define the paths for where we'll place stuff on the endpoint
$MSPRoot = $Env:MSPDir
$MSPScripts = "${MSPRoot}\Scripts"
$MSPTools = "${MSPRoot}\Tools"
$MSPLogs = "${MSPRoot}\Logs"

## Function to simply import a module and return an error message if it fails
Function Load-Module
{
    param([string]$modulename)

    ## Get a new copy of the module
    Get-Module $modulename

    ## Form the local file path to the specified module
    $FilePath = "${ModulePath}\${modulename}.psm1"

    ## Import the module
    If ( Test-Path $FilePath )
    {
        Try { Import-Module -Name $FilePath }
        Catch { Write-Output $_.Exception.Message }
    } Else { Write-Output "Module does not exist: ${FilePath}" }
}

## Function to update or install a module
Function Get-Module
{
    param([string]$modulename)

    ## Form the URL to the specified module
    $ModuleURL = "${BaseURL}/${modulename}.psm1"

    ## Form the local file path to the specified module
    $FilePath = "${ModulePath}\${modulename}.psm1"

    ## Download the new file, overwriting the local copy
    If ( IsDownloadable $ModuleURL )
    {
        Try { (New-Object Net.WebClient).DownloadFile($ModuleURL, $FilePath) }
        Catch { Write-Output $_.Exception.Message }
    } Else { Write-Output "Could not download ${ModuleURL}" }
}

## Determines whether a file can be downloaded or not
Function IsDownloadable
{
    param([string]$url)

    ## Create a web request
    $HTTPRequest = [System.Net.WebRequest]::Create($url)

    Try
    {
        ## Get the response
        $HTTPResponse = $HTTPRequest.GetResponse()

        ## Save the status code
        $HTTPStatus = [int]$HTTPResponse.StatusCode
    }
    Catch [System.Net.WebException] { $HTTPResponse = $_.Exception.Response }

    ## Close the connection, because we're done with it
    Finally { $HTTPResponse.Close() }

    ## Test to make sure we received a status of 200 "OK" from the resource
    If ($HTTPStatus -eq 200) { Return $true }

    ## If the status code is anything other than 200, return $false
    Else { Return $false }
}

## EXPORT FUNCTION
## Function to log activity to the configured log directory
Function global:Log
{
    Begin {}
    Process {}
    End {}
}

## EXPORT FUNCTION
## Function to determine if the current user context is an Administrator
Function global:IsAdmin
{
    Begin {}
    Process
    {
        If ( ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator) )
        { Return $true } Else { Return $false }
    }
    End {}
}

## EXPORT FUNCTION
## Function to retrieve and run a powershell script
Function Run-PSScript
{
    param(
        [string]$Type='management-scripts',
        [string]$Name,
        [string]$Arguments
    )

    ## Form the URL to the specified script
    $URL = "https://dev.emberkom.com/emberkom/${Type}/raw/branch/master/${Name}.ps1"

    If ( IsDownloadable $URL )
    {
        $Script = (New-Object Net.WebClient).DownloadString($URL)
        $ScriptBlock = [Scriptblock]::Create($Script)
        Try { Invoke-Command -ScriptBlock $ScriptBlock -ArgumentList $Arguments }
        Catch { Write-Output $_.Exception.Message }
    } Else { Write-Output "Could not retrieve ${URL}" }
}

## Make sure all the management directories exist
If ( !(Test-Path $MSPRoot) )
{
    Try { New-Item -Path $MSPRoot -ItemType Directory -Force | Out-Null }
    Catch { Write-Output $_.Exception.Message }
}
If ( !(Test-Path $MSPScripts) )
{
    Try { New-Item -Path $MSPScripts -ItemType Directory -Force | Out-Null }
    Catch { Write-Output $_.Exception.Message }
}
If ( !(Test-Path $MSPTools) )
{
    Try { New-Item -Path $MSPTools -ItemType Directory -Force | Out-Null }
    Catch { Write-Output $_.Exception.Message }
}
If ( !(Test-Path $MSPLogs) )
{
    Try { New-Item -Path $MSPLogs -ItemType Directory -Force | Out-Null }
    Catch { Write-Output $_.Exception.Message }
}

## Import all modules
$ListOfModules = @(
    "PSModule",
    "PSModule-SetWinEvtLog"
)
ForEach ($module in $ListOfModules) { Load-Module $module }

## Make sure this module exports only the functions that should be exported
Export-ModuleMember -Function Log,IsAdmin,Run-PSScript