#############################################################################################
# This script downloads, if necessary, Promtail and its WinSW (Windows Service wrapper), 
# creates default configuration and creates Windows service.
# It's a decision based script.
# 
# ↓ ↓ ↓ ↓       HELPER FUNCTIONS    ↓ ↓ ↓ ↓
# ↓↓↓↓↓↓↓       PROCESSING CODE     ↓↓↓↓↓↓↓
#############################################################################################

param(
  ## https://devblogs.microsoft.com/powershell/v2-custom-enums/ better, but limited to alphanumeric, so *DHCP would not work
  [Parameter(Mandatory=$true, HelpMessage="Hotel site e.g. gb-bw-peartree-manchester, bikes, gb-ihg-holidayinn-birmingham")][String]$HotelGroup,
  [Parameter(Mandatory=$true, HelpMessage="Hotel site e.g. operaapp, checkin, ")][ValidateSet('operaapp','checkin','hopapp')][String]$apptype,
  [Parameter(Mandatory=$true, HelpMessage="Kiosk Number e.g. 1, 2, 3, 4 (use the numeric) ")][String]$kiosknumber,
  [Parameter(Mandatory=$true, HelpMessage="Have you updated the following Group Policy? Computerconfig > windows settings > security settings > advanced audit policy config > object access > double click audit removable storage.(yes/no)")][ValidateSet('yes')][String]$gpochange
  )

function Prompt-User {
    param(
        [string]$Prompt,
        [object]$Default
    )

    if (-not [string]::IsNullOrEmpty($Default)) {
        if ($Default -is [bool]) {
            $Prompt += " [$(if ($Default) {'True'} else {'False'})]"
        }
        else {
            $Prompt += " [$Default]"
        }
    }

    $input = Read-Host -Prompt $Prompt

    if ([string]::IsNullOrEmpty($input)) {
        $input = $Default
    }
    else {
        if ($Default -is [bool]) {
            $input = [bool]::Parse($input)
        }
        elseif ($Default -is [int]) {
            $input = [int]::Parse($input)
        }
        elseif ($Default -is [string]) {
            # No conversion needed for string
        }
        else {
            throw "Unsupported default value type: $($Default.GetType().FullName)"
        }

        if ($input.GetType() -ne $Default.GetType()) {
            throw "Entered value type doesn't match default value type"
        }
    }

    return $input
}

function Ensure-Directory {
    param(
        [string]$Path
    )

    if (-not [System.IO.Directory]::Exists($Path)) {
        [System.IO.Directory]::CreateDirectory($Path) | Out-Null
    }
}

function Download-File {
    param (
        # Url of file to download
        [Parameter(Mandatory)]
        [string]$URL,
  
        # Parameter help description
        [Parameter(Mandatory)]
        [string]$File 
    )
    Begin {
        function Show-Progress {
            param (
                # Enter total value
                [Parameter(Mandatory)]
                [Single]$TotalValue,
        
                # Enter current value
                [Parameter(Mandatory)]
                [Single]$CurrentValue,
        
                # Enter custom progresstext
                [Parameter(Mandatory)]
                [string]$ProgressText,
        
                # Enter value suffix
                [Parameter()]
                [string]$ValueSuffix,
        
                # Enter bar lengh suffix
                [Parameter()]
                [int]$BarSize = 40,

                # show complete bar
                [Parameter()]
                [switch]$Complete
            )
            
            # calc %
            $percent = $CurrentValue / $TotalValue
            $percentComplete = $percent * 100
            if ($ValueSuffix) {
                $ValueSuffix = " $ValueSuffix" # add space in front
            }
            if ($psISE) {
                Write-Progress "$ProgressText $CurrentValue$ValueSuffix of $TotalValue$ValueSuffix" -id 0 -percentComplete $percentComplete            
            }
            else {
                # build progressbar with string function
                $curBarSize = $BarSize * $percent
                $progbar = ""
                $progbar = $progbar.PadRight($curBarSize, [char]9608)
                $progbar = $progbar.PadRight($BarSize, [char]9617)
        
                if (!$Complete.IsPresent) {
                    Write-Host -NoNewLine "`r$ProgressText $progbar [ $($CurrentValue.ToString("#.###").PadLeft($TotalValue.ToString("#.###").Length))$ValueSuffix / $($TotalValue.ToString("#.###"))$ValueSuffix ] $($percentComplete.ToString("##0.00").PadLeft(6)) % complete"
                }
                else {
                    Write-Host -NoNewLine "`r$ProgressText $progbar [ $($TotalValue.ToString("#.###").PadLeft($TotalValue.ToString("#.###").Length))$ValueSuffix / $($TotalValue.ToString("#.###"))$ValueSuffix ] $($percentComplete.ToString("##0.00").PadLeft(6)) % complete"                    
                }                
            }   
        }
    }
    Process {
        try {
            $storeEAP = $ErrorActionPreference
            $ErrorActionPreference = 'Stop'
        
            # invoke request
            $request = [System.Net.HttpWebRequest]::Create($URL)
            $response = $request.GetResponse()
  
            if ($response.StatusCode -eq 401 -or $response.StatusCode -eq 403 -or $response.StatusCode -eq 404) {
                throw "Remote file either doesn't exist, is unauthorized, or is forbidden for '$URL'."
            }
  
            if ($File -match '^\.\\') {
                $File = Join-Path (Get-Location -PSProvider "FileSystem") ($File -Split '^\.')[1]
            }
            
            if ($File -and !(Split-Path $File)) {
                $File = Join-Path (Get-Location -PSProvider "FileSystem") $File
            }

            if ($File) {
                $fileDirectory = $([System.IO.Path]::GetDirectoryName($File))
                if (!(Test-Path($fileDirectory))) {
                    [System.IO.Directory]::CreateDirectory($fileDirectory) | Out-Null
                }
            }

            [long]$fullSize = $response.ContentLength
            $fullSizeMB = $fullSize / 1024 / 1024
  
            # define buffer
            [byte[]]$buffer = new-object byte[] 1048576
            [long]$total = [long]$count = 0
  
            # create reader / writer
            $reader = $response.GetResponseStream()
            $writer = new-object System.IO.FileStream $File, "Create"
  
            # start download
            $finalBarCount = 0 #show final bar only one time
            do {
          
                $count = $reader.Read($buffer, 0, $buffer.Length)
          
                $writer.Write($buffer, 0, $count)
              
                $total += $count
                $totalMB = $total / 1024 / 1024
          
                if ($fullSize -gt 0) {
                    Show-Progress -TotalValue $fullSizeMB -CurrentValue $totalMB -ProgressText "Downloading $($File.Name)" -ValueSuffix "MB"
                }

                if ($total -eq $fullSize -and $count -eq 0 -and $finalBarCount -eq 0) {
                    Show-Progress -TotalValue $fullSizeMB -CurrentValue $totalMB -ProgressText "Downloading $($File.Name)" -ValueSuffix "MB" -Complete
                    $finalBarCount++
                    #Write-Host "$finalBarCount"
                }

            } while ($count -gt 0)
        }
  
        catch {
        
            $ExeptionMsg = $_.Exception.Message
            Write-Host "Download breaks with error : $ExeptionMsg"
        }
  
        finally {
            # cleanup
            if ($reader) { $reader.Close() }
            if ($writer) { $writer.Flush(); $writer.Close() }
        
            $ErrorActionPreference = $storeEAP
            [GC]::Collect()

            Write-Host 
        }    
    }
}

function New-DefaultConfig {
    param (
        # Parameter help description
        [Parameter(Mandatory)]
        [string]$fullConfigPath,
        [Parameter(Mandatory)]
        [string]$runPath
    )

    Write-Output "Writing default config to $fullConfigPath"

    $positionsFullpath = $runPath + "\positions.yaml"

    $content = "
# 1. Update positions.yaml path
# 2. Update client's url - this is the url of Loki service - update or remove basic_auth
# 3. Update what logs should be scraped


server:
  http_listen_port: 9081
  grpc_listen_port: 0

positions:
  filename: 'C:\ProgramData\Promtail\positions.txt'

clients:
  - url: 'https://loki.futuresens.co.uk/loki/api/v1/push'

scrape_configs:
  - job_name: testapptype
    static_configs:
    - targets:
      - localhost
      labels:
        hotel: testhotel
        job: testapptype
        kiosk: testkiosknumber
        __path__: 'C:\Program Files\Self-Service Technology\Logs\testhotel.log'
  - job_name: sst
    static_configs:
    - targets:
      - localhost
      labels:
        hotel: testhotel
        job: sst
        kiosk: testkiosknumber
        __path__: 'C:\Program Files\Self-Service Technology\Logs\SST.Browser.log'
  - job_name: windows-system
    windows_events: 
      eventlog_name: 'Microsoft-Windows-DriverFrameworks-UserMode/Operational'
      labels:
        logsource: windows-eventlog
        hotel: gb-i-peartree-salisbury
        job: winlogs
        kiosk: testkiosknumber
      use_incoming_timestamp: true
      bookmark_path: 'C:\ProgramData\Promtail\bookmark-system.xml'
      exclude_event_data: true
      exclude_user_data: true
      locale: 1033
"
  $content = $content.Replace('testhotel',"$HotelGroup")
  $content = $content.Replace('testapptype',"$apptype")
  $content = $content.Replace('testkiosknumber',"$kiosknumber")

    Set-Content -Path $fullConfigPath -Value $content
}

function New-DefaultWinSWConfig {
    param (
        # Parameter help description
        [Parameter(Mandatory)]
        [string]$fullConfigPath,
        [Parameter(Mandatory)]
        [string]$fullPromtailBinPath,
        [Parameter(Mandatory)]
        [string]$fullPromtailConfigPath,
        [Parameter(Mandatory)]
        [string]$serviceName,
        [Parameter(Mandatory)]
        [string]$serviceDisplayName
    )

    Write-Output "Writing default WinSW config to $fullConfigPath"

    $content = "
    <!--
    You can find more information about the configuration options here: https://github.com/kohsuke/winsw/blob/master/doc/xmlConfigFile.md
    Full example: https://github.com/kohsuke/winsw/blob/master/examples/sample-allOptions.xml
   -->
   <service>
     
     <!-- ID of the service. It should be unique across the Windows system-->
     <id>$serviceName</id>
     <!-- Display name of the service -->
     <name>$serviceDisplayName</name>
     <!-- Service description -->
     <description>Starts a local Promtail service and scrapes logs according to configuration file: $fullPromtailConfigPath</description>
     
     <!-- Path to the executable, which should be started -->
     <executable>""$fullPromtailBinPath""</executable>
   
     <arguments>--config.file=""$fullPromtailConfigPath""</arguments>
   
   </service>
"

    Set-Content -Path $fullConfigPath -Value $content
}


#############################################
# ↑ ↑ ↑ ↑   HELPER FUNCTIONS          ↑ ↑ ↑ ↑   
# 
#
# ↓ ↓ ↓ ↓   PROCESSING CODE           ↓ ↓ ↓ ↓
#############################################


Write-Warning -Message "This script creates a Window Service for Promtail log scraper. It is necessary to run it with Admin priviledges.

It can download necessary files from the Internet, but you can also put already downloaded files directly to proper directories."

## Below will enable event logs to allow the USB decetion logs.

$logDetails = Get-LogProperties 'Microsoft-Windows-DriverFrameworks-UserMode/Operational'
$logDetails.Enabled = $True
Set-LogProperties -LogDetails $logDetails
Get-LogProperties 'Microsoft-Windows-DriverFrameworks-UserMode/Operational'

## The below line will update the group Policy to enable the removeable storage audit, if GP edit exists

if (Test-Path 'C:\Windows\System32\gpedit.msc') {
    Write-Host 'Enabling Group Policy - Audit removeable storage.'
    auditpol /set /subcategory:"Removable Storage" /success:enable /failure:enable    
}
else{
    Write-Host 'c:\Windows\System32\gpedit.msc does NOT exist, Exiting on safety grounds'
    exit
}

$downloadUrl = "https://github.com/grafana/loki/releases/download/v2.9.5/promtail-windows-amd64.exe.zip"
$downloadWinSWUrl = "https://github.com/winsw/winsw/releases/download/v2.12.0/WinSW-x64.exe"
$winSWFilename = "WinSW-x64.exe"
$binFilename = "promtail-windows-amd64.exe"
$configFilename = "promtail.yml"
$winSWConfigFilename = "WinSW-x64.xml"

$runPath = Prompt-User -Prompt "Run directory" -Default "C:\Promtail"
$fullBinPath = Join-Path -Path $runPath -ChildPath $binFilename
$fullWinSWBinPath = Join-Path -Path $runPath -ChildPath $winSWFilename
$downloadWinSWPath = $runPath

$shouldDownloadPromtail = Prompt-User -Prompt "Should we download Promtail?" -Default $true

if ($shouldDownloadPromtail) {
    $downloadUrl = Prompt-User -Prompt "Download url" -Default $downloadUrl
    $downloadPath = Prompt-User -Prompt "Download directory" -Default $runPath

    Ensure-Directory -Path $downloadPath
    Ensure-Directory -Path 'c:\ProgramData\Promtail'

    ## Now create the positions files. NB Please create a Positions file for each Job.

    New-Item -Path 'c:\ProgramData\Promtail\positions.txt' -ItemType File
    New-Item -Path 'c:\ProgramData\Promtail\bookmark-system.xml' -ItemType File

    $filename = $downloadUrl.Split("/")[-1]
    $fullPath = Join-Path -Path $downloadPath -ChildPath $filename

    Write-Host "Downloading archive..."
    Download-File -URL $downloadUrl -File $fullPath

    Write-Host "Expanding archive..."
    Expand-Archive -LiteralPath $fullPath -DestinationPath $runPath -Force
} 
else {
    if (-not [System.IO.File]::Exists($fullBinPath)) {
        throw "Could not find $fullBinPath"
    }
}

$shouldCreateConfig = Prompt-User -Prompt "Create default promtail.yml config?" -Default $true
$configFullpath = Join-Path -Path $runPath -ChildPath $configFilename

if ($shouldCreateConfig) {
    New-DefaultConfig -fullConfigPath $configFullpath -runPath $runPath
}
else {
    $configFullpath = Prompt-User -Prompt "Promtail configuration file path" -Default $configFullpath

    if (-not [System.IO.File]::Exists($configFullpath)) {
        throw "Could not find $configFullpath"
    }
}

$shouldCreateService = Prompt-User -Prompt "Create Promtail Windows service?" -Default $true

if ($shouldCreateService) {

    $shouldDownloadWinSWUrl = Prompt-User -Prompt "Should we download Windows Service wrapper (WinSWUrl)?" -Default $true

    if ($shouldDownloadWinSWUrl) {
        $downloadUrl = Prompt-User -Prompt "Download url" -Default $downloadWinSWUrl
        $downloadWinSWPath = Prompt-User -Prompt "Download directory" -Default $runPath
    
        Ensure-Directory -Path $downloadPath
    
        $filename = $winSWFilename
        $fullWinSWBinPath = Join-Path -Path $downloadWinSWPath -ChildPath $filename
    
        Write-Host "Downloading WinSW exe file..."
        Download-File -URL $downloadUrl -File $fullWinSWBinPath
    } 
    else {
        if (-not [System.IO.File]::Exists($fullWinSWBinPath)) {
            throw "Could not find $fullWinSWBinPath"
        }
    }
    

    $winSWconfigFullpath = Join-Path -Path $downloadWinSWPath -ChildPath $winSWConfigFilename
    $shouldCreateWinSWConfig = Prompt-User -Prompt "Create WinSW config as $winSWconfigFullpath ?" -Default $true
    
    if ($shouldCreateWinSWConfig) {
        $serviceName = Prompt-User -Prompt "Service name" -Default "Promtail"
        $serviceDisplayName = Prompt-User -Prompt "Service name" -Default "Promtail Logs scraper"

        New-DefaultWinSWConfig -fullConfigPath $winSWconfigFullpath -fullPromtailBinPath $fullBinPath -fullPromtailConfigPath $configFullpath -serviceName $serviceName -serviceDisplayName $serviceDisplayName
    }
    else {
        if (-not [System.IO.File]::Exists($winSWconfigFullpath)) {
            throw "Could not find $winSWconfigFullpath"
        }
    }

    gpupdate /force

    Write-Host "Installing Promtail Windows Service"
    
    Start-Process -FilePath $fullWinSWBinPath -ArgumentList @("install") -NoNewWindow

    Write-Host "Starting the Service"

    start-sleep -Seconds 5

    Start-Service Promtail

    Set-ExecutionPolicy Restricted -Force

    Write-Host "Reverting execution policy"
}