Universal DetectionMethod.ps1

<#
.SYNOPSIS
    Retrieves information about installed applications based on different search modes.
.DESCRIPTION
    The Get-InstalledApps function retrieves information about installed applications based on various search modes 
    such as Registry, CmCIM, or File. It allows querying by application name, version, and search mode.
.PARAMETER Appname
    The name of the application to search for.
.PARAMETER Version
    The version of the application to search for.
.PARAMETER VersionOperator
    The version comparison operator. Valid values are "EQ" (equal) and "GE" (greater than or equal). Default is "GE".
.PARAMETER SearchMode
    The search mode to use. Valid values are "Registry", "CmCIM", "AppX" or "File".
.PARAMETER FilePath
    The file path to the application if using the "File" search mode.
.EXAMPLE
    Get-InstalledApps -Appname "FortiClient" -Version "7.2.4.09" -SearchMode CmCIM
    Retrieves information about the "FortiClient" application with version "7.2.4.09" using the CmCIM search mode.
.EXAMPLE
    Get-InstalledApps -Appname "FortiClient" -Version "7.2.4.09" -SearchMode Registry -VersionOperator GE
    Retrieves information about installed instances of the "FortiClient" application with version greater than or equal to "7.2.4.09" using the Registry search mode.
.EXAMPLE
    Get-InstalledApps -Appname "FortiClient" -Version "7.2.4.09" -SearchMode File -FilePath "C:\Program Files\Fortinet\FortiClient\FortiClient.exe" -VersionOperator EQ 
    Retrieves information about the "FortiClient" application with version "7.2.4.09" located at the specified file path using the File search mode.
#>
function Get-InstalledApps
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $false, ParameterSetName ='list')]
        [switch]$List,
    
        [Parameter(Mandatory = $false, ParameterSetName ='detect')]
        [string]$Appname,

        [Parameter(Mandatory = $false, ParameterSetName ='detect')]
        [string]$Version,

        [Parameter(Mandatory = $false, ParameterSetName ='detect')]
        [validateset("EQ","GE")]
        [string]$VersionOperator = "GE", 

        [Parameter(Mandatory = $false, ParameterSetName ='list')]
        [Parameter(Mandatory = $true, ParameterSetName ='detect')]
        [validateset("Registry","CmCIM", "File","Appx")]
        [string]$SearchMode,

        [Parameter(Mandatory = $false, ParameterSetName ='detect')]
        [string]$FilePath,

        # Exact name matching
        [Parameter(Mandatory = $false, ParameterSetName ='detect')]
        [switch]$ExactName
    )
    
    begin 
    {        
        switch ($SearchMode)
        {
            "Registry"
            {
                $AppsFound = @()
                $x86Apps = Get-ItemProperty -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\* | 
                    Select-Object Displayname, Displayversion, Publisher, installdate, UninstallString
                $x64Apps = Get-ItemProperty -Path HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\* | 
                    Select-Object Displayname, Displayversion, Publisher, installdate, UninstallString
                $AppsFound += $x86Apps
                $AppsFound += $x64Apps
            }
            "CmCIM"
            {
                $AppsFound = get-CimInstance -Namespace root/cimv2/sms -ClassName SMS_InstalledSoftware | 
                    Select-Object @{Label='Displayname'; Expression = {$_.ARPDisplayName}}, 
                                  @{Label='DisplayVersion'; Expression = {$_.ProductVersion}}, 
                                  Publisher, InstallDate, UninstallString
            }
            "File"
            {
                $AppsFound = Get-ItemProperty -Path $FilePath -ErrorAction Ignore | 
                    Select-Object @{Label='Displayname'; Expression = {$_.BaseName}}, 
                                  @{Label='DisplayVersion'; Expression = {$_.VersionInfo.FileVersion}}
            }
            "Appx"
            {
                $AppsFound = Get-AppxPackage -AllUsers | 
                    Select-Object @{Label='Displayname'; Expression = {$_.Name}}, 
                                  @{Label='DisplayVersion'; Expression = {$_.Version}}, 
                                  Publisher
            }
            Default
            {
                $AppsFound = @()
                $x86Apps = Get-ItemProperty -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\* | 
                    Select-Object Displayname, Displayversion, Publisher, installdate, UninstallString
                $x64Apps = Get-ItemProperty -Path HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\* | 
                    Select-Object Displayname, Displayversion, Publisher, installdate, UninstallString
                $AppsFound += $x86Apps
                $AppsFound += $x64Apps
            }
        }
    }
    
    process
    {
        if (-not $List)
        {
            if ($ExactName)
            {
                # Perform exact match
                $AppInfo = $AppsFound | Where-Object { $_.Displayname -eq $Appname }
            }
            else
            {
                # Perform partial match
                $AppInfo = $AppsFound | Where-Object { $_.Displayname -match [regex]::Escape($Appname) }
            }

            if ($AppInfo)
            {
                $AppVersionFound = $AppInfo.DisplayVersion -as [string]
                $AppVersionSearch = $Version -as [string]

                $IsNumericVersion = $AppVersionSearch -match "^\d+(\.\d+)*$"

                if ($IsNumericVersion)
                {
                    try
                    {
                        $AppVersionFound = [version]$AppVersionFound
                        $AppVersionSearch = [version]$AppVersionSearch

                        switch ($VersionOperator) 
                        {
                            "GE" { $Appfound = $AppVersionFound -ge $AppVersionSearch }
                            "EQ" { $Appfound = $AppVersionFound -eq $AppVersionSearch }
                        }
                    }
                    catch
                    {
                        $Appfound = $false
                    }
                }
                else
                {
                    if ($AppVersionFound -match [regex]::Escape($AppVersionSearch))
                    {
                        $Appfound = $true
                    }
                    else
                    {
                        $Appfound = $false
                    }
                }
            }
            else
            {
                $Appfound = $false
            }
        }
    }
    
    end
    {
        if ($List)
        {
            $AppToDetect = $AppsFound | Out-GridView -Title "Select the app you want to detect:" -PassThru            
            Write-Host "Get-InstalledApps -Appname `"$($AppToDetect.Displayname)`" -Version `"$($AppToDetect.Displayversion)`" -SearchMode $SearchMode"
        }
        else 
        {
            if ($Appfound -eq $true)
            {
                Write-Host "Installed"
            }
        }       
    }   
}