##########################################################################################
#
# Site.js 20220914151124 (17.8.0/5cba1ee) Installer for Windows 10 (PowerShell)
#
# To use:
#
# iex(iwr -UseBasicParsing https://sitejs.org/windows).Content
#
# Copyright (c) 2019-2020 Aral Balkan.
# Released under the AGPL version 3.0 or later license.
# Made with <3 by Small Technology Foundation (https://small-tech.org)
# Like this? Fund us! (https://small-tech.org/fund-us)
#
##########################################################################################

# This is where the binary will be installed to.
$installationDirectory =  'C:\Program Files\site.js'

# The address to download the installation script from.
$installationScriptUrl = 'https://sitejs.org/install.txt'

# Installation script local file name.
$installationScriptFileName = 'install-site.js.ps1'

# The address to download the tar-gzipped archive of the Site.js binary from.
$archiveUrl = 'https://sitejs.org/binaries/release/windows/20220914151124.tar.gz'

# Emoji encodings (because Powershell is from the Stone Age and cannot handle
# emoji literals in strings)

$satelliteBytes = 240, 159, 147, 161
$packageBytes = 240, 159, 147, 166
$tadaBytes = 240, 159, 142, 137
$satelliteEmoji = [System.Text.Encoding]::UTF8.GetString($satelliteBytes)
$packageEmoji = [System.Text.Encoding]::UTF8.GetString($packageBytes)
$tadaEmoji = [System.Text.Encoding]::UTF8.GetString($tadaBytes)
$ellipsis = [char]0x2026

# Adds to the specified environment path without creating duplicates.
# Courtesy of https://gist.github.com/mkropat/c1226e0cc2ca941b23a9
# Via https://stackoverflow.com/questions/714877/setting-windows-powershell-environment-variables
function Add-EnvPath {
  param(
    [Parameter(Mandatory=$true)]
    [string] $Path,

    [ValidateSet('Machine', 'User', 'Session')]
    [string] $Container = 'Session'
  )

  if ($Container -ne 'Session') {
    $containerMapping = @{
      Machine = [EnvironmentVariableTarget]::Machine
      User = [EnvironmentVariableTarget]::User
    }
    $containerType = $containerMapping[$Container]

    $persistedPaths = [Environment]::GetEnvironmentVariable('Path', $containerType) -split ';'
    if ($persistedPaths -notcontains $Path) {
      $persistedPaths = $persistedPaths + $Path | Where-Object { $_ }
      [Environment]::SetEnvironmentVariable('Path', $persistedPaths -join ';', $containerType)
    }
  }

  $envPaths = $env:Path -split ';'
  if ($envPaths -notcontains $Path) {
    $envPaths = $envPaths + $Path | Where-Object { $_ }
    $env:Path = $envPaths -join ';'
  }
}

# Switch to the temp folder. This is where we will always be working from
# so as not to pollute any persistent directories.
Push-Location "~\AppData\Local\Temp\"

# Check if we're running with elevated privileges, if not, start a new
# PowerShell windows with elevated privileges and continue there.
if (!([Security.Principal.WindowsPrincipal] `
  [Security.Principal.WindowsIdentity]::GetCurrent() `
).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
  #
  # Installer is running with regular privileges.
  #

  #
  # Installer is running with regular privileges. Start a new PowerShell session with elevated privileges.
  #
  Write-Output ''
  Write-Output " $satelliteEmoji Downloading Site.js 20220914151124 (17.8.0/5cba1ee)$ellipsis"

  # We need to start a new PowerShell session with elevated privileges but if we're running in memory
  # only after being downloaded by the installation command, we don't have a copy of ourselves to run.
  # So download the latest version of this script and save it there so that we can run it with elevated privileges.
  Invoke-WebRequest $installationScriptUrl -OutFile $installationScriptFileName

  # Run the downloaded version of ourself with elevated privileges.
  $currentPath = (Get-Item -Path ".\").FullName
  Start-Process -Verb RunAs powershell.exe -Wait -ArgumentList "$currentPath/$installationScriptFileName"

  # We're back from the privileged window. Update this window's path immediately so that
  # the person can use the site command right away from the current session.
  $env:Path += ";$installationDirectory"

  # Recreate the output from the other window for consistency with other platforms.
  Write-Output " $packageEmoji Installing$ellipsis"
  Write-Output " $tadaEmoji Done! "
  Write-Output ''
} else {
  #
  # Installer is running with elevated privileges.
  #
  Write-Output "`n`n`n`n`n`n"
  Write-Output ' Installing Site.js using administrator privileges...'
  Write-Output ''
  Write-Output ' * Downloading Site.js 20220914151124 (17.8.0/5cba1ee)...'

  # Download the latest Site.js archive.
  Invoke-WebRequest -Uri $archiveUrl -OutFile '20220914151124.tar.gz'

  Write-Output ''
  Write-Output ' * Extracting binary...'

  # Gunzip and untar the binary.
  tar -xf 20220914151124.tar.gz

  Write-Output ''
  Write-Output ' * Installing binary...'

  # Ensure that the folder we want to copy the binary to exists.
  New-Item -Force -ItemType directory -Path $installationDirectory | Out-Null
  Copy-Item -Force -Path ./site.exe -Destination $installationDirectory | Out-Null

  Write-Output ''
  Write-Output ' * Adding to system path...'

  # Persist the installation directory to the system path
  # (if it doesn't already exist).
  Add-EnvPath -Container Machine -Path $installationDirectory

  Write-Output ''
  Write-Output ' * Done!'
  Write-Output ''

  # Give people a chance to read the output.
  Start-Sleep -Seconds 1
}

# Revert to whatever directory the person was in originally.
Pop-Location