Convert natural language commands into executable PowerShell using OpenAI

Invoke-OpenAI

<#
    Aims to grow the understanding of using OpenAI in PoweShell by providing an example of an implementation and references
#>

function Invoke-OpenAI {
    <#
        .SYNOPSIS
        Convert natural language commands into commands in PowerShell

        .EXAMPLE
        Invoke-OpenAI "# What's my IP?" 

        .EXAMPLE
        Invoke-OpenAI "# how many processes are running with more than 700 handles?""

        .LINK
    #>
    param(
        [Parameter(Mandatory)]
        $userQuery,
        $maxTokens = 100
    )

    if(!$env:OpenAIKey) {
        $msg = '$env:OpenAIKey is not set'
        $msg += 'You need to get one here: https://beta.openai.com/account/api-keys'
        
        throw ($msg -join "`r`n")
    }

    $url = 'https://api.openai.com/v1/engines/davinci/completions'
    
    $prefix = "<# powershell #>"
    $codex_query = '{0} {1}' -f $prefix, $userQuery

    $payload = @{
        prompt      = $codex_query
        temperature = 0
        max_tokens  = $maxTokens
        stop        = "#" 
    }

    $irmParams = @{
        Uri         = $url 
        Method      = 'Post' 
        ContentType = 'application/json'
        Headers     = @{Authorization = "Bearer $($env:OpenAIKey)" } 
        Body        = $payload | ConvertTo-Json
    }

    $r = Invoke-RestMethod @irmParams
    $r.choices[0].Text.Trim()
}

Set-PSReadLineKeyHandler -Key Ctrl+g `
                         -BriefDescription NLCLI `
                         -LongDescription "Calls Codex CLI tool on the current buffer" `
                         -ScriptBlock {
    param($key, $arg)
    
    $line = $null
    $cursor = $null

    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$line, [ref]$cursor)

    # get response from create_completion function
    $output = Invoke-OpenAI $line
    
    # check if output is not null
    if ($output -ne $null) {
        foreach ($str in $output) {
            if ($str -ne $null -and $str -ne "") {
                [Microsoft.PowerShell.PSConsoleReadLine]::AddLine()
                [Microsoft.PowerShell.PSConsoleReadLine]::Insert($str)
            }
        }
    }
}