feat(prettier): add PowerShell installer

prettier/install.ps1

@@ -0,0 +1,59 @@
+#!/usr/bin/env pwsh
+
+####################
+# Install prettier #
+####################
+
+function command-v-silent($cmdname) {
+    $my_cmd = Get-Command $command -ErrorAction SilentlyContinue
+    # $my_path = $my_cmd | Select-Object -ExpandProperty Definition
+
+    if ($my_cmd) {
+        return True
+    }
+    return False
+}
+
+function mktemp-d-t() {
+    # create random suffix for dirname
+    $my_bytes = New-Object byte[] 4
+    $my_rng = [Security.Cryptography.RNGCryptoServiceProvider]::Create()
+    $my_rng.GetBytes($bytes)
+    $my_hex_delimited = [BitConverter]::ToString($bytes)
+    $my_hex = $my_hex_delimited -replace "-", ""
+
+    # create random directory
+    $my_systmpdir = [System.IO.Path]::GetTempPath()
+    $my_tmpdir =  Join-Path "$my_systmpdir" "$my_hex"
+    New-Item -ItemType Directory -Path "$my_tmpdir"
+
+    return "$my_tmpdir"
+}
+
+function npm-install-global($pkgname) {
+    # Fetch npm package manager
+    Write-Output "Checking for npm..."
+    if (-Not (command-v-silent("npm"))) {
+        & "$Env:USERPROFILE\.local\bin\webi-pwsh.ps1" node
+    }
+
+    if (command-v-silent($pkgname)) {
+        $my_cmd = Get-Command $pkgname
+        $my_cmd Select-Object -ExpandProperty Definition
+        Write-Host "Found '$my_cmd'"
+        return
+    }
+
+    $my_tmpdir = mktemp-d-t()
+
+    # npm install works best from a directory with no package.json
+    Push-Location "$my_tmpdir"
+    if (command-v-silent("npm")) {
+        & npm --location-golbal prettier
+    } else {
+        & "$Env:USERPROFILE\.local\opt\node\npm" --location-golbal "$pkgname"
+    }
+    Pop-Location
+}
+
+npm-install-global prettier