Powershell script to reduce typing SSH command

sss.ps1

#member -in $args
[CmdletBinding(PositionalBinding=$false)]
param(
    [Parameter(Position=0)]
    [string]$Name,
    [switch]$Add,
    [switch]$List,
    [switch]$Help,
    [Parameter(
        ValueFromRemainingArguments = $true
    )]
    [Object[]]$Remain
)

function Add-Host {
    param(
        [string]$Name,
        [string]$Hostname,
        [string]$Username,
        [string]$AuthType,
        [string]$Password,
        [string]$KeyPath
    )
    $sshHosts.add($Name, [PSCustomObject]@{
        Name = $Name;
        Host = $Hostname;
        Username = $Username;
        AuthType = $AuthType;
        Password = $Password;
        KeyPath = $KeyPath;
    })
    Save-Config
}

function Save-Config {
    ConvertTo-Json $sshHosts | Out-File $fullPath
}

function Connect-Name {
    param([string]$Name)
    if ($sshHosts.ContainsKey($Name)) {
        $hostname = $sshHosts[$Name].host
        $username = $sshHosts[$Name].username
        $password = $sshHosts[$Name].password
        $cmd = "ssh $username@$hostname"
        if ($sshHosts[$Name].authtype -eq 'key'){
            $keypath = $sshHosts[$Name].keypath
            $cmd += " -i ""$keypath"""
        }
        Invoke-Expression $cmd
        exit
    }else{
        echo "Unknown name $Name"
        echo "Use 'sss -add $Name' to configurate this host"
        exit
    }
}

Add-Type -AssemblyName System.Windows.Forms
function Open-FileDialog {
    $fd = New-Object System.Windows.Forms.OpenFileDialog
    $fd.ShowDialog() | out-null
    return $fd.FileName
}

$configFile = 'sss.json'

$fullPath = [System.IO.Path]::Combine($env:USERPROFILE, $configFile)

$sshHosts = @{}

if ([System.IO.File]::Exists($fullPath)){
    (Get-Content $fullPath | ConvertFrom-Json).psobject.properties | Foreach { $sshHosts[$_.Name] = $_.Value }
}

if ($Help) {
    echo "Save your time typing SSH hostname and private key path"
    echo "Usage:`n`tsss [name]`tConnect to host"
    echo "Parameters:"
    echo "`t-add [name]`tAdd a SSH host"
    echo "`t-list`t`tList added hosts"
    echo "`t-help`t`tShow this message"
    exit
}

if ($add) {
    if (-not $Name) {$Name = Read-Host "Friendly name"}
    if ($sshHosts.ContainsKey($Name)) {echo "This name have been added."; exit}
    $hostname = Read-Host "IP address or hostname"
    $username = Read-Host "Login name"
    $authtype = Read-Host "Auth type (pw or key)"
    $password = ''
    $keypath = ''
    if ($authtype -eq 'key'){
        $keypath = Open-FileDialog
    }
    Add-Host $Name $hostname $username $authtype $password $keypath
    echo "`nHost added"
    exit
}

if ($sshHosts.Count -eq 0){
    echo "You haven't add any host. Use 'sss -add' to add a host"
    exit
}

if ($List) {
    $sshHosts.Values | select name | ft
    exit
}

if ($Name) {
    Connect-Name $Name
}

$sshHosts.Values | select name | ft
$Name = Read-Host "Enter name"
if (-not $Name) {exit}
Connect-Name $Name