Install-PowerShellGet.ps1

#Requires -PSEdition Desktop

[CmdletBinding()]
param (
    [ValidateSet('AllUsers', 'CurrentUser')]
    [string]
    $Scope = 'CurrentUser'
)

$ErrorActionPreference = 'Stop'

[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 'Tls12'

if ($Scope -eq 'AllUsers') {
    $basePath = $env:ProgramFiles
} else {
    $basePath = [Environment]::GetFolderPath('MyDocuments')
}
$modulePath = Join-Path -Path $basePath -ChildPath 'WindowsPowerShell\Modules'

$packages = @(
    @{ Name = 'PackageManagement'; Version = '1.4.8.1' }
    @{ Name = 'PowerShellGet';     Version = '2.2.5' }
)
foreach ($package in $packages) {
    try {
        $params = @{
            Uri     = 'https://psg-prod-eastus.azureedge.net/packages/{0}.{1}.nupkg' -f @(
                $package['Name'].ToLower()
                $package['Version']
            )
            OutFile = Join-Path -Path $env:TEMP -ChildPath ('{0}.zip' -f $package['Name'])
        }
        Write-Verbose ('Downloading {0} from {1}' -f $package['Name'], $params['Uri'])
        Invoke-WebRequest @params

        $params = @{
            Path            = $params['OutFile']
            DestinationPath = Join-Path -Path $modulePath -ChildPath $package['Name'] |
                Join-Path -ChildPath $package['Version']
            Force           = $true
        }
        if (-not (Test-Path -LiteralPath $params['DestinationPath'])) {
            New-Item -Path $params['DestinationPath'] -ItemType Directory
        }
        Write-Verbose ('Extracting {0} to {1}' -f $package['Name'], $params['DestinationPath'])
        Expand-Archive @params
        Remove-Item -LiteralPath $params['Path']

        Write-Verbose ('Cleaning package {0}' -f $package['Name'])
        $params = @{
            Path    = $params['DestinationPath']
            Depth   = 0
            Include = @(
                '_rels'
                '*Content_Types*'
                'package'
                '*.nuspec'
            )
        }
        Get-ChildItem @params | Remove-Item -Recurse
    } catch {
        Write-Error -ErrorRecord $_
    }
}