param(
    [string]$ServerUrl = "http://localhost:8080"
)

$ComputerName = $env:COMPUTERNAME
$User = [System.Security.Principal.WindowsIdentity]::GetCurrent().Name
$IPAddress = (Get-NetIPAddress -AddressFamily IPv4 -InterfaceAlias "Ethernet*", "Wi-Fi*" | Select-Object -First 1).IPAddress
$MacAddress = (Get-NetAdapter | Where-Object { $_.Status -eq 'Up' } | Select-Object -First 1).MacAddress
$LastSeen = Get-Date -Format "yyyy-MM-dd HH:mm:ss"

# Get installed software from registry (32 and 64 bit)
$SoftwareList = New-Object System.Collections.Generic.List[PSCustomObject]
$RegistryPaths = @(
    "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*",
    "HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\*",
    "HKCU:\Software\Microsoft\Windows\CurrentVersion\Uninstall\*"
)

foreach ($Path in $RegistryPaths) {
    Get-ItemProperty $Path -ErrorAction SilentlyContinue | Where-Object { $_.DisplayName -ne $null } | ForEach-Object {
        $SoftwareList.Add([PSCustomObject]@{
            Name    = [string]$_.DisplayName
            Version = [string]$_.DisplayVersion
        })
    }
}

# Unique list and sort (Now works correctly with PSCustomObject)
$Software = $SoftwareList | Sort-Object Name -Unique

$Inventory = @{
    ComputerName = $ComputerName
    User         = $User
    IPAddress    = $IPAddress
    MacAddress   = $MacAddress
    LastSeen     = $LastSeen
    Software     = $Software
}

# Convert to JSON
$Json = $Inventory | ConvertTo-Json -Depth 10

# FIX FOR POWERSHELL 5.1: Ensure Software is always an array
# If Software has only 1 item, ConvertTo-Json creates an object {} instead of an array [{}]
if ($Software.Count -eq 1) {
    # Find the Software block and wrap it in brackets if it's not already an array
    # This regex is more robust: it looks for the Software key followed by an object start {
    $Json = $Json -replace '("Software":\s*)\{', '$1[{'
    # And then closes the bracket after that object
    $Json = $Json -replace '(\s+)(\d+|".*?"|null|true|false)\s+\},(\s+"[A-Z])', '$1$2$1}],$3'
    # If Software was the last element in the JSON
    $Json = $Json -replace '(\s+)(\d+|".*?"|null|true|false)\s+\}\s+\}', '$1$2$1}] }'
}

try {
    $Response = Invoke-RestMethod -Uri "$ServerUrl/inventory" -Method Post -Body $Json -ContentType "application/json"
    Write-Host "Inventory sent successfully to $ServerUrl"
} catch {
    Write-Error "Failed to send inventory: $_"
    if ($_.Exception.Response) {
        $Reader = New-Object System.IO.StreamReader($_.Exception.Response.GetResponseStream())
        $ErrorBody = $Reader.ReadToEnd()
        Write-Host "Error Body: $ErrorBody" -ForegroundColor Red
    }
}