param(
  [Parameter(Mandatory=$true)][string] $InputPath,       # Full path to directory where NuGet packages to be checked are stored
  [Parameter(Mandatory=$true)][string] $ExtractPath,     # Full path to directory where the packages will be extracted during validation
  [Parameter(Mandatory=$true)][string] $SymbolToolPath   # Full path to directory where dotnet symbol-tool was installed
)

Add-Type -AssemblyName System.IO.Compression.FileSystem

function FirstMatchingSymbolDescriptionOrDefault {
  param( 
    [string] $FullPath,                  # Full path to the module that has to be checked
    [string] $TargetServerParam,         # Parameter to pass to `Symbol Tool` indicating the server to lookup for symbols
    [string] $SymbolsPath
  )

  $FileName = [System.IO.Path]::GetFileName($FullPath)
  $Extension = [System.IO.Path]::GetExtension($FullPath)

  # Those below are potential symbol files that the `dotnet symbol` might
  # return. Which one will be returned depend on the type of file we are
  # checking and which type of file was uploaded.

  # The file itself is returned
  $SymbolPath = $SymbolsPath + "\" + $FileName

  # PDB file for the module
  $PdbPath = $SymbolPath.Replace($Extension, ".pdb")

  # PDB file for R2R module (created by crossgen)
  $NGenPdb = $SymbolPath.Replace($Extension, ".ni.pdb")

  # DBG file for a .so library
  $SODbg = $SymbolPath.Replace($Extension, ".so.dbg")

  # DWARF file for a .dylib
  $DylibDwarf = $SymbolPath.Replace($Extension, ".dylib.dwarf")
 
  .\dotnet-symbol.exe --symbols --modules --windows-pdbs $TargetServerParam $FullPath -o $SymbolsPath | Out-Null

  if (Test-Path $PdbPath) {
    return "PDB"
  }
  elseif (Test-Path $NGenPdb) {
    return "NGen PDB"
  }
  elseif (Test-Path $SODbg) {
    return "DBG for SO"
  }  
  elseif (Test-Path $DylibDwarf) {
    return "Dwarf for Dylib"
  }  
  elseif (Test-Path $SymbolPath) {
    return "Module"
  }
  else {
    return $null
  }
}

function CountMissingSymbols {
  param( 
    [string] $PackagePath          # Path to a NuGet package
  )

  # Ensure input file exist
  if (!(Test-Path $PackagePath)) {
    throw "Input file does not exist: $PackagePath"
  }
  
  # Extensions for which we'll look for symbols
  $RelevantExtensions = @(".dll", ".exe", ".so", ".dylib")

  # How many files are missing symbol information
  $MissingSymbols = 0

  $PackageId = [System.IO.Path]::GetFileNameWithoutExtension($PackagePath)
  $PackageGuid = New-Guid
  $ExtractPath = Join-Path -Path $ExtractPath -ChildPath $PackageGuid
  $SymbolsPath = Join-Path -Path $ExtractPath -ChildPath "Symbols"
  
  [System.IO.Compression.ZipFile]::ExtractToDirectory($PackagePath, $ExtractPath)

  # Makes easier to reference `symbol tool`
  Push-Location $SymbolToolPath

  Get-ChildItem -Recurse $ExtractPath |
    Where-Object {$RelevantExtensions -contains $_.Extension} |
    ForEach-Object {
      if ($_.FullName -Match "\\ref\\") {
        Write-Host "`t Ignoring reference assembly file" $_.FullName
        return
      }

      $SymbolsOnMSDL = FirstMatchingSymbolDescriptionOrDefault $_.FullName "--microsoft-symbol-server" $SymbolsPath
      $SymbolsOnSymWeb = FirstMatchingSymbolDescriptionOrDefault $_.FullName "--internal-server" $SymbolsPath

      Write-Host -NoNewLine "`t Checking file" $_.FullName "... "
  
      if ($SymbolsOnMSDL -ne $null -and $SymbolsOnSymWeb -ne $null) {
        Write-Host "Symbols found on MSDL (" $SymbolsOnMSDL ") and SymWeb (" $SymbolsOnSymWeb ")"
      }
      else {
        $MissingSymbols++

        if ($SymbolsOnMSDL -eq $null -and $SymbolsOnSymWeb -eq $null) {
          Write-Host "No symbols found on MSDL or SymWeb!"
        }
        else {
          if ($SymbolsOnMSDL -eq $null) {
            Write-Host "No symbols found on MSDL!"
          }
          else {
            Write-Host "No symbols found on SymWeb!"
          }
        }
      }
    }
  
  Pop-Location

  return $MissingSymbols
}

function CheckSymbolsAvailable {
  if (Test-Path $ExtractPath) {
    Remove-Item $ExtractPath -Force  -Recurse -ErrorAction SilentlyContinue
  }

  Get-ChildItem "$InputPath\*.nupkg" |
    ForEach-Object {
      $FileName = $_.Name
	  
      # These packages from Arcade-Services include some native libraries that
      # our current symbol uploader can't handle. Below is a workaround until
      # we get issue: https://github.com/dotnet/arcade/issues/2457 sorted.
      if ($FileName -Match "Microsoft\.DotNet\.Darc\.") {
        Write-Host "Ignoring Arcade-services file: $FileName"
        Write-Host
        return
      }
      elseif ($FileName -Match "Microsoft\.DotNet\.Maestro\.Tasks\.") {
        Write-Host "Ignoring Arcade-services file: $FileName"
        Write-Host
        return
      }
	  
      Write-Host "Validating $FileName "
      $Status = CountMissingSymbols "$InputPath\$FileName"
  
      if ($Status -ne 0) {
        Write-Error "Missing symbols for $Status modules in the package $FileName"
      }

      Write-Host
    }
}

CheckSymbolsAvailable