#Requires -Version 5.0
# Offline regression tests. BITS and URL resolution are mocked.
$ErrorActionPreference = 'Stop'
$DownloadToolsPath = Join-Path (Split-Path $PSScriptRoot -Parent) 'Tools.ps1'
$DownloadTokens = $null
$DownloadParseErrors = $null
$DownloadAst = [Management.Automation.Language.Parser]::ParseFile($DownloadToolsPath, [ref]$DownloadTokens, [ref]$DownloadParseErrors)
If ($DownloadParseErrors.Count) { Throw ($DownloadParseErrors | Out-String) }
$DownloadDefinition = $DownloadAst.Find({
    param($Node)
    $Node -is [Management.Automation.Language.FunctionDefinitionAst] -and $Node.Name -eq 'Download-File'
}, $true)
. ([scriptblock]::Create($DownloadDefinition.Extent.Text))

Function Get-AbsoluteURI { param($URL) Return $URL }
Function Start-BitsTransfer {
    [CmdletBinding()]
    param($Source, $Destination)
    If ($script:DownloadTestMode -eq 'success') {
        [IO.File]::WriteAllText($Destination, 'Synthetic download.')
        Return
    }
    [IO.File]::WriteAllBytes($Destination, [byte[]]@())
    If ($script:DownloadTestMode -eq 'terminating-error') { Throw 'Synthetic BITS connection failure.' }
    Microsoft.PowerShell.Utility\Write-Error 'Synthetic BITS TLS failure.'
}

$DownloadTestRoot = Join-Path ([IO.Path]::GetTempPath()) ('download-file-tests-' + [guid]::NewGuid().ToString('N'))
$null = New-Item -Path $DownloadTestRoot -ItemType Directory
Try {
    $DownloadTestFile = Join-Path $DownloadTestRoot 'collector $test.exe'
    $script:DownloadTestMode = 'success'
    $DownloadResult = Download-File -URL 'https://example.invalid/collector.exe' -File $DownloadTestFile
    If ($DownloadResult -cne $DownloadTestFile -or [IO.File]::ReadAllText($DownloadResult) -cne 'Synthetic download.') {
        Throw 'Successful download did not return the completed file.'
    }
    Write-Host 'PASS: successful download returns its destination.'

    Foreach ($script:DownloadTestMode in @('nonterminating-error','terminating-error')) {
        # Match an RMM that uses the normal Continue preference and does not pass -ErrorAction.
        $ErrorActionPreference = 'Continue'
        $DownloadCaught = $null
        $DownloadReturnedPaths = @()
        Try {
            Download-File -URL 'https://example.invalid/collector.exe' -File $DownloadTestFile |
                ForEach-Object { $DownloadReturnedPaths += $_ }
        }
        Catch { $DownloadCaught = $_ }
        Finally { $ErrorActionPreference = 'Stop' }
        If ($null -eq $DownloadCaught -or $DownloadCaught.Exception.Message -notlike '*Synthetic BITS*failure*') {
            Throw 'Failed transfer must throw and preserve the BITS error.'
        }
        If ($DownloadReturnedPaths.Count -ne 0) { Throw 'Failed transfer returned a success path.' }
        Write-Host "PASS: $script:DownloadTestMode stops the caller and preserves the transfer error."
    }
    Write-Host "All Download-File tests passed on PowerShell $($PSVersionTable.PSVersion), $([IntPtr]::Size * 8)-bit."
}
Finally {
    $DownloadResolvedRoot = (Resolve-Path -LiteralPath $DownloadTestRoot).Path
    $DownloadTempRoot = [IO.Path]::GetFullPath([IO.Path]::GetTempPath()).TrimEnd('\') + '\'
    If (!$DownloadResolvedRoot.StartsWith($DownloadTempRoot, [StringComparison]::OrdinalIgnoreCase) -or
        (Split-Path $DownloadResolvedRoot -Leaf) -notlike 'download-file-tests-*') { Throw 'Unexpected cleanup directory.' }
    Remove-Item -LiteralPath $DownloadResolvedRoot -Recurse -Force
}