# Installs the newest Termilly for you, on 64-bit Windows 10 or 11:
#
#   irm https://termilly.com/install.ps1 | iex
#
# It reads https://termilly.com/downloads/latest.json, downloads the online installer named there, checks its
# SHA-256 against that file and runs it with --quiet. The installer fetches .NET and WebView2 from Microsoft when
# they're missing. It's short on purpose, so you can read it before you run it. $env:TERMILLY_SITE points it at
# another server, for testing.

# One script block: "irm | iex" runs nothing until the whole script is here, and a failure ends the block, not
# your PowerShell window (exit would close it).
$code = & {
    $ErrorActionPreference = 'Stop'
    $ProgressPreference = 'SilentlyContinue' # Windows PowerShell's progress bar makes downloads many times slower
    [Net.ServicePointManager]::SecurityProtocol = [Net.ServicePointManager]::SecurityProtocol -bor [Net.SecurityProtocolType]::Tls12
    $site = if ($env:TERMILLY_SITE) { $env:TERMILLY_SITE } else { 'https://termilly.com' }
    $dir = Join-Path ([IO.Path]::GetTempPath()) ('termilly-install-' + [Guid]::NewGuid().ToString('N'))
    try {
        if (-not [Environment]::Is64BitOperatingSystem) { throw 'Termilly needs 64-bit Windows 10 or 11.' }
        try {
            $manifest = Invoke-RestMethod -UseBasicParsing "$site/downloads/latest.json"
        } catch {
            throw "Couldn't read $site/downloads/latest.json: $($_.Exception.Message)"
        }
        $version = $manifest.version
        $url = $manifest.windows.online
        $sum = $manifest.windows.sha256
        if (-not $version -or -not $url -or -not $sum) { throw "$site/downloads/latest.json doesn't name a Windows installer." }
        if (-not $env:TERMILLY_SITE -and -not $url.StartsWith('https://')) { throw "The installer's address isn't HTTPS: $url" }

        New-Item -ItemType Directory $dir | Out-Null
        $exe = Join-Path $dir 'TermillySetup-online.exe'
        Write-Host "Downloading Termilly $version"
        try {
            Invoke-WebRequest -UseBasicParsing $url -OutFile $exe
        } catch {
            throw "Couldn't download ${url}: $($_.Exception.Message)"
        }
        if ((Get-FileHash -Algorithm SHA256 $exe).Hash -ne $sum) {
            throw "The download doesn't match the SHA-256 in latest.json, so it wasn't installed. Try again later."
        }

        Write-Host 'Installing it'
        $setup = [Diagnostics.Process]::Start($exe, '--quiet')
        $setup.WaitForExit()
        switch ($setup.ExitCode) {
            0 { Write-Host "Termilly $version is installed. Start it from the Start menu, or type termilly in a new terminal." }
            740 { Write-Host 'termilly install: setup needs to run as administrator.' -ForegroundColor Red }
            default { Write-Host "termilly install: setup failed (exit code $_). Its log is in $env:TEMP\TermillySetup-*\setup.log" -ForegroundColor Red }
        }
        $setup.ExitCode
    } catch {
        Write-Host "termilly install: $($_.Exception.Message)" -ForegroundColor Red
        1
    } finally {
        Remove-Item -Recurse -Force -ErrorAction SilentlyContinue $dir
    }
}

# Setup's exit code, for scripts (and install.cmd) to check. No exit: under "irm | iex" it would close the caller.
$global:LASTEXITCODE = $code