# Funktion zum Konvertieren des LastLogonTimestamp in Datum
function Convert-LastLogonTimestamp {
    param (
        [Parameter(Mandatory = $true)]
        [long]$Timestamp
    )

    $DateTime = [DateTime]::FromFileTime($Timestamp)
    return $DateTime
}

# Funktion zum Abrufen der lokalen IP-Adresse
function Get-LocalIPAddress {
    $ipAddress = [System.Net.Dns]::GetHostAddresses([System.Net.Dns]::GetHostName()) |
        Where-Object { $_.AddressFamily -eq 'InterNetwork' } |
        Select-Object -First 1
    return $ipAddress.IPAddressToString
}

# Gruppe "Users" abrufen
$groupName = "Reporting"
$group = Get-ADGroup -Filter { Name -eq $groupName }

if ($group -eq $null) {
    Write-Error "Gruppe '$groupName' wurde nicht gefunden."
    exit
}

# Mitglieder der Gruppe abrufen
$groupMembers = Get-ADGroupMember -Identity $group -Recursive | Where-Object { $_.objectClass -eq 'user' }

# Abrufen der lokalen IP-Adresse
$localIPAddress = Get-LocalIPAddress

# Erstellen einer Hash-Tabelle zum Speichern der letzten Anmeldeinformationen für jeden Benutzer
$userLogins = @{}

# Umwandeln der Benutzerinformationen und Ausgabe zur Konsole
foreach ($member in $groupMembers) {
    $user = Get-ADUser -Identity $member.SamAccountName -Properties LastLogonTimestamp,createTimeStamp
    $lastLogonDateTime = if ($user.LastLogonTimestamp) { (Convert-LastLogonTimestamp -Timestamp $user.LastLogonTimestamp).ToString("yyyy-MM-dd HH:mm:ss") } else { ($user.createTimeStamp).ToString("yyyy-MM-dd HH:mm:ss") }

    $convertedUser = [PSCustomObject]@{
        username        = $user.SamAccountName
        lastaccess      = $lastLogonDateTime
        ipaddress       = $localIPAddress
    }

    # Ausgabe des konvertierten Benutzers zur Konsole
    Write-Output $convertedUser

    # Rückgabe des konvertierten Benutzers für JSON-Umwandlung
    $userLogins[$user.SamAccountName] = $convertedUser
}

# Define the JSON file path with current date and hour
$dateString = (Get-Date).ToString("yyyyMMdd_HH-mm")
$jsonPath = "C:\Scripte\LastLogins_$dateString.json"

# Output the last login event for each user to the JSON file
$userLoginsArray = $userLogins.GetEnumerator() | ForEach-Object {
    $_.Value
}

$userLoginsArray | ConvertTo-Json | Set-Content -Path $jsonPath -Encoding UTF8

Write-Output "JSON file created at $jsonPath"

# API endpoint URL
$apiUrl = "http://api.stines.de:8001/report"

# Your API key
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("Content-Type", "application/json")
$headers.Add("access_token", "^YWUbG7yX*V!tV^KBSd*2c&vdN3wV9a2i7f3hfGFMBYFxi6#mMiJGiaA5KEHE%B*miK%qb7rQ67gmcYP@gqmux8")

# Loop through the collected user logins and send each as a JSON payload to the API
foreach ($userLogin in $userLoginsArray) {
    $userLoginObject = $userLogin | Select-Object username, lastaccess, ipaddress

    # Convert the user login object to JSON
    $jsonPayload = $userLoginObject | ConvertTo-Json -Depth 3

    # Encode JSON payload in UTF-8
    $utf8JsonPayload = [System.Text.Encoding]::UTF8.GetBytes($jsonPayload)

    # Send the JSON payload to the API
    try {
        $response = Invoke-RestMethod -Uri $apiUrl -Method Post -Body $utf8JsonPayload -ContentType 'application/json' -Headers $headers
        Write-Output "Sent login data for user $($userLoginObject.username) to the API. Response: $response"
    } catch {
        Write-Error "Failed to send login data for user $($userLoginObject.username). Error: $_"
    }
}

Write-Output "Finished sending login data to the API"