Mini-u.ps1

function Draw-Menu {
    [CmdletBinding()]
    param (
        [Parameter()]
        [String[]]
        $menuItems,
        [Parameter()]
        [int32]
        $menuPosition,
        [Parameter()]
        [String]
        $menuTitle,
        [Parameter()]
        [System.Object]
        $object,
        [Parameter()]
        [String]
        $navigation,
        [Parameter()]
        [String[]]
        $selections,
        [Parameter()]
        [String]
        $secondaryKey = 'Description',
        [Parameter()]
        [String]
        $tertiaryKey = 'Navigation'
    )

    $menuLength = $menuItems.length
    $consoleWidth = $host.ui.RawUI.WindowSize.Width
    $foregroundColor = $host.UI.RawUI.ForegroundColor
    $backgroundColor = $host.UI.RawUI.BackgroundColor
    $leftTitlePadding = ($consoleWidth - $menuTitle.Length) / 2
    $titlePaddingString = ' ' * ([Math]::Max(0, $leftTitlePadding))
    $leftDescriptionPadding = ($consoleWidth - $secondaryKey.Length) / 2
    $descriptionPaddingString = ' ' * ([Math]::Max(0, $leftDescriptionPadding))
    $leftTertiaryKeyPadding = ($consoleWidth - $tertiaryKey.Length) / 2
    $tertiaryKeyPaddingString = ' ' * ([Math]::Max(0, $leftTertiaryKeyPadding))
    $leftNavigationPadding = ($consoleWidth - $navigation.Length) / 2
    $navigationPaddingString = ' ' * ([Math]::Max(0, $leftNavigationPadding))

    Clear-Host
    Write-Host $('-' * $consoleWidth -join '')
    Write-Host ($titlePaddingString)($menuTitle)
    Write-Host $('-' * $consoleWidth -join '')

    $currentDescription = ""

    for ($i = 0; $i -lt $menuLength; $i++) {
        Write-Host "`t" -NoNewLine
        if ($i -eq $menuPosition) {
            if ($menuItems[$i] -in $selections) {
                Write-Host "+ $($menuItems[$i])" -ForegroundColor $backgroundColor -BackgroundColor $foregroundColor
            } else {
                Write-Host "$($menuItems[$i])" -ForegroundColor $backgroundColor -BackgroundColor $foregroundColor
            }
            $currentItem = $menuItems[$i]
            $currentDescription = ($object | Where-Object { $_.Name -eq $currentItem }).Value.Description
        } else {
            if ($menuItems[$i] -in $selections) {
                Write-Host "+ $($menuItems[$i])" -ForegroundColor $foregroundColor -BackgroundColor $backgroundColor
            } else {
                Write-Host "$($menuItems[$i])" -ForegroundColor $foregroundColor -BackgroundColor $backgroundColor
            }
        }
    }

    Write-Host $('-' * $consoleWidth -join '')
    Write-Host ($descriptionPaddingString)($secondaryKey)
    Write-Host $('-' * $consoleWidth -join '')
    # Display the description after the menu is rendered.
    Write-Host "`t$currentDescription"

    Write-Host `n
    Write-Host `n
    Write-Host $('-' * $consoleWidth -join '')
    Write-Host ($navigationPaddingString)($navigation)
}

function Navigate-Menu {
    [CmdletBinding()]
    param (
        [Parameter()]
        [String[]]
        $menuItems,
        [Parameter()]
        [String]
        $menuTitle = "Menu",
        [Parameter()]
        [System.Object]
        $object,
        [Parameter()]
        [String]
        $navigation,
        [Parameter()]
        [String[]]
        $selections
    )
    $keycode = 0
    $pos = 0
    
    while ($keycode -ne 13 -and $keycode -ne 81 -and $keycode -ne 8) {
        Draw-Menu $menuItems $pos $menuTitle $object $navigation $selections
        $press = $host.ui.rawui.readkey("NoEcho,IncludeKeyDown")
        $keycode = $press.virtualkeycode
        if ($keycode -eq 8) {
            $global:back = $true
            break
        }
        if ($keycode -eq 81) {
            $global:quit = $true
            break
        }
        if ($keycode -eq 69) {
            $global:execute = $true
            break
        }
        if ($keycode -eq 38) {
            $pos--
        }
        if ($keycode -eq 40) {
            $pos++
        }
        if ($pos -lt 0) {
            $pos = ($menuItems.length - 1)
        }
        if ($pos -ge $menuItems.length) {
            $pos = 0
        }
    }

    if ($null -ne $($menuItems[$pos]) -and !$global:quit -and !$global:back -and !$global:execute) {
        return $($menuItems[$pos])
    }
}
function mini-u {
<#
.SYNOPSIS
	This function serves as an example of how I implement command line 
    interface menus in PowerShell. To use this, run 
    'Import-Module .\Mini-u.ps1' from within this project's directory.
.DESCRIPTION
    Using a JSON file, a main menu is generated which contain names to
    objects within the JSON file that serve as submenus. Each submenu 
    has addition objects that can be selected. Edit the JSON file to 
    create your desired menu layout, currently limited to a depth of
    10.
.NOTES
	Author:     Lucas McGlamery
.EXAMPLE
	PS> mini-u
#>
    [bool]$global:back = $false
    [bool]$global:quit = $false
    [bool]$global:execute = $false
    $MainMenu = (Get-Content .\menus\MainMenu.json | ConvertFrom-Json -Depth 10).PSObject.Properties
    $MenuStack = New-Object System.Collections.ArrayList
    $MultiMenuSelections = New-Object System.Collections.ArrayList
    # generate navigation help
    $Navigation = Get-Content .\menus\Navigation.json | ConvertFrom-Json
    $Navigation = $Navigation | ForEach-Object {
        "[$($_.Key)]-$($_.Function)"
    }
    $Navigation = $Navigation -join " "

    # begin main loop
    while(!$global:quit) {
        # check and reset if 'E' was pressed outside of multi-selection menu
        if ($global:execute) {
            $global:execute = $false
        }
        if ($global:back) {
            $MenuStack.Remove($MenuStack[-1])
            $MultiMenuSelections.Clear()
            $global:back = $false
        }
        if ($null -eq $MenuStack[0]) {
            $MainMenuSelection = Navigate-Menu $MainMenu.Name "Main Menu" $MainMenu $Navigation
            if ($global:quit -or $global:back) {
                continue
            }
            $MenuStack.Add(($MainMenu[$MainMenuSelection]))
        } else {
            $CurrentObject = $MenuStack[-1].Value | %{$_.PSObject.Properties}
            $SubMenu = ($CurrentObject | ?{$_.Name -notin 'Description','Menu_Type'})
            # check if current menu allows for multiple selections
            if ('Multiple_Selection' -in $CurrentObject.value) {
                while (!$global:back -and !$global:quit) {
                    if ($global:execute) {
                        Write-Host "Executing selections..."
                        $MultiMenuSelections | ForEach-Object {
                            $curObj = $_
                            Invoke-Expression (($Submenu | ?{$_.name -eq $curObj}).value).ScriptText
                        }
                        $MultiMenuSelections.Clear()
                        $global:execute = $false
                    }
                    $Selection = Navigate-Menu $SubMenu.Name "Select a submenu option" $SubMenu $Navigation $MultiMenuSelections
                    if ($Selection -in $MultiMenuSelections) {
                        $MultiMenuSelections.Remove($Selection)
                    } else {
                        $MultiMenuSelections.Add($Selection)
                    }
                }
                continue
            }
            if ('Single_Select_and_Exit' -in $CurrentObject.value) {
                $Selection = Navigate-Menu $SubMenu.Name "Select a submenu option" $SubMenu $Navigation
                if (!$global:back) {
                    $global:quit = $true
                    return ($SubMenu | ?{$_.Name -eq $Selection}).value.selection
                    continue
                } else {
                    continue
                }
            }
            $Selection = Navigate-Menu $SubMenu.Name "Select a submenu option" $SubMenu $Navigation
            if ($global:quit -or $global:back) {
                continue
            }
            if ($null -ne (($Submenu | ?{$_.name -eq $Selection}).value).ScriptText) {
                Invoke-Expression (($Submenu | ?{$_.name -eq $Selection}).value).ScriptText
            } else {
                $MenuStack.Add(($Submenu | ?{$_.name -eq $Selection}))
            }
        }
    }
    Clear-Host
}