# Installs the opposable command line tool from getopposable.com on Windows.
#
#   irm https://getopposable.com/install.ps1 | iex
#
# It downloads the Windows build, checks it against the published SHA-256 sums, puts opposable.exe in
# %LOCALAPPDATA%\Opposable\bin and adds that folder to your user PATH. No administrator rights needed.
# Settings: $env:OPPOSABLE_INSTALL_DIR to choose the folder, $env:OPPOSABLE_VERSION to pick another version.

function Install-Opposable {
  $ErrorActionPreference = 'Stop'
  $ProgressPreference = 'SilentlyContinue'
  [Net.ServicePointManager]::SecurityProtocol = [Net.ServicePointManager]::SecurityProtocol -bor [Net.SecurityProtocolType]::Tls12

  $version = if ($env:OPPOSABLE_VERSION) { $env:OPPOSABLE_VERSION } else { '0.3.0-preview.1' }
  $base = if ($env:OPPOSABLE_BASE_URL) { $env:OPPOSABLE_BASE_URL } else { 'https://getopposable.com' }
  $dir = if ($env:OPPOSABLE_INSTALL_DIR) { $env:OPPOSABLE_INSTALL_DIR } else { Join-Path $env:LOCALAPPDATA 'Opposable\bin' }

  $arch = $env:PROCESSOR_ARCHITECTURE
  if ($env:PROCESSOR_ARCHITEW6432) { $arch = $env:PROCESSOR_ARCHITEW6432 }
  if ($arch -ne 'AMD64' -and $arch -ne 'ARM64') { throw "opposable install: no Windows build for $arch yet" }
  # Windows on ARM runs the x64 build under emulation.

  $name = "opposable-$version-windows-x64.zip"
  $url = if ($env:OPPOSABLE_VERSION) { "$base/download/cli/$name" } else { "$base/get/cli-windows-x64?src=install-ps1" }
  $tmp = Join-Path ([IO.Path]::GetTempPath()) ("opposable-" + [Guid]::NewGuid().ToString('N'))
  New-Item -ItemType Directory -Path $tmp | Out-Null
  try {
    Write-Host "Downloading opposable $version for Windows..."
    $sums = (Invoke-WebRequest -UseBasicParsing -Uri "$base/download/cli/SHA256SUMS").Content
    if ($sums -is [byte[]]) { $sums = [Text.Encoding]::UTF8.GetString($sums) }
    $zip = Join-Path $tmp $name
    Invoke-WebRequest -UseBasicParsing -Uri $url -OutFile $zip

    $line = ($sums -split "`n") | Where-Object { $_.Trim().EndsWith(" $name") } | Select-Object -First 1
    if (-not $line) { throw "opposable install: $name isn't listed in SHA256SUMS" }
    $want = ($line.Trim() -split '\s+')[0].ToLower()
    $got = (Get-FileHash -Algorithm SHA256 -Path $zip).Hash.ToLower()
    if ($want -ne $got) { throw "opposable install: checksum mismatch for $name (expected $want, got $got). Nothing was installed." }

    Expand-Archive -Path $zip -DestinationPath (Join-Path $tmp 'x') -Force
    New-Item -ItemType Directory -Path $dir -Force | Out-Null
    Copy-Item -Path (Join-Path $tmp 'x\opposable.exe') -Destination (Join-Path $dir 'opposable.exe') -Force
    Copy-Item -Path (Join-Path $tmp 'x\NOTICES.txt') -Destination (Join-Path $dir 'NOTICES.txt') -Force
  } finally {
    Remove-Item -Recurse -Force $tmp -ErrorAction SilentlyContinue
  }

  $userPath = [Environment]::GetEnvironmentVariable('Path', 'User')
  $parts = @()
  if ($userPath) { $parts = $userPath -split ';' | Where-Object { $_ } }
  if ($parts -notcontains $dir) {
    [Environment]::SetEnvironmentVariable('Path', (($parts + $dir) -join ';'), 'User')
    Write-Host "Added $dir to your user PATH. Open a new terminal window to use it."
  }
  if (($env:Path -split ';') -notcontains $dir) { $env:Path = "$env:Path;$dir" }

  $v = & (Join-Path $dir 'opposable.exe') --version
  Write-Host "Installed $v to $dir\opposable.exe"
  Write-Host ""
  Write-Host "Next: in the Opposable app on your phone, tap Pair with computer, then run"
  Write-Host "  opposable connect CODE"
}

Install-Opposable