#-----------------------------------------------------------------------------
#
#  Copyright (c) 2021, Thierry Lelegard
#  BSD-2-Clause license, see LICENSE.txt file or https://tsduck.io/license
#
#-----------------------------------------------------------------------------

<#
 .SYNOPSIS

  Download and install TSDuck for Windows.

  This is a sample script which can be used by other projects which need TSDuck.

 .PARAMETER All

  Install all options. By default, only the tools, plugins and documentation
  are installed. In case of upgrade over an existing installation, the default
  is to upgrade the same options as in the previous installation.

 .PARAMETER Destination

  Specify a local directory where the package will be downloaded.
  By default, use the downloads folder for the current user.

 .PARAMETER ForceDownload

  Force a download even if the package is already downloaded.

 .PARAMETER GitHubActions

  When used in a GitHub Action workflow, make sure that the required
  environment variables are propagated to subsequent jobs.

 .PARAMETER NoInstall

  Do not install the package. By default, the package is installed.

 .PARAMETER NoPause

  Do not wait for the user to press <enter> at end of execution. By default,
  execute a "pause" instruction at the end of execution, which is useful
  when the script was run from Windows Explorer.
#>
[CmdletBinding(SupportsShouldProcess=$true)]
param(
    [switch]$All = $false,
    [string]$Destination = "",
    [switch]$ForceDownload = $false,
    [switch]$GitHubActions = $false,
    [switch]$NoInstall = $false,
    [switch]$NoPause = $false
)

Write-Output "==== TSDuck download and installation procedure"

# Web page for the latest releases.
$ReleasePage = "https://github.com/tsduck/tsduck/releases/latest"

# A function to exit this script.
function Exit-Script([string]$Message = "")
{
    $Code = 0
    if ($Message -ne "") {
        Write-Output "ERROR: $Message"
        $Code = 1
    }
    if (-not $NoPause) {
        pause
    }
    exit $Code
}

# Without this, Invoke-WebRequest is awfully slow.
$ProgressPreference = 'SilentlyContinue'

# Get the HTML page for latest package release.
$status = 0
$message = ""
$Ref = $null
try {
    $response = Invoke-WebRequest -UseBasicParsing -UserAgent Download -Uri $ReleasePage
    $status = [int] [Math]::Floor($response.StatusCode / 100)
}
catch {
    $message = $_.Exception.Message
}

if ($status -ne 1 -and $status -ne 2) {
    # Error fetching download page.
    if ($message -eq "" -and (Test-Path variable:response)) {
        Write-Output "Status code $($response.StatusCode), $($response.StatusDescription)"
    }
    else {
        Write-Output "#### Error accessing ${ReleasePage}: $message"
    }
}
else {
    # Parse HTML page to locate the latest installer.
    $Ref = $response.Links.href | Where-Object { $_ -like "*/TSDuck-Win64-*.exe" } | Select-Object -First 1
}

if (-not $Ref) {
    # Could not find a reference to installer.
    Exit-Script "Could not find a reference to installer in ${ReleasePage}"
}
else {
    # Build the absolute URL's from base URL (the download page) and href links.
    $Url = New-Object -TypeName 'System.Uri' -ArgumentList ([System.Uri]$ReleasePage, $Ref)
}

# Create the directory for external products or use default.
if (-not $Destination) {
    $Destination = (New-Object -ComObject Shell.Application).NameSpace('shell:Downloads').Self.Path
}
else {
    [void](New-Item -Path $Destination -ItemType Directory -Force)
}

# Local installer file.
$InstallerName = (Split-Path -Leaf $Url.LocalPath)
$InstallerPath = "$Destination\$InstallerName"

# Download installer.
if (-not $ForceDownload -and (Test-Path $InstallerPath)) {
    Write-Output "$InstallerName already downloaded, use -ForceDownload to download again"
}
else {
    Write-Output "Downloading $Url ..."
    Invoke-WebRequest -UseBasicParsing -UserAgent Download -Uri $Url -OutFile $InstallerPath
    if (-not (Test-Path $InstallerPath)) {
        Exit-Script "$Url download failed"
    }
}

# Install package.
if (-not $NoInstall) {
    Write-Output "Installing $InstallerName"
    $ArgList = @("/S")
    if ($All) {
        $ArgList += "/all=true"
    }
    Start-Process -FilePath $InstallerPath -ArgumentList $ArgList -Wait
}

# Propagate Path in next jobs for GitHub Actions.
if ($GitHubActions) {
    $tsduck     = [System.Environment]::GetEnvironmentVariable("TSDUCK",     [System.EnvironmentVariableTarget]::Machine)
    $path       = [System.Environment]::GetEnvironmentVariable("Path",       [System.EnvironmentVariableTarget]::Machine)
    $pythonpath = [System.Environment]::GetEnvironmentVariable("PYTHONPATH", [System.EnvironmentVariableTarget]::Machine)
    $classpath  = [System.Environment]::GetEnvironmentVariable("CLASSPATH",  [System.EnvironmentVariableTarget]::Machine)
    Write-Output "TSDUCK=$tsduck"         | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
    Write-Output "Path=$path"             | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
    Write-Output "PYTHONPATH=$pythonpath" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
    Write-Output "CLASSPATH=$classpath"   | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
}

Exit-Script
