function Get-MailboxInboxRules {
    [cmdletbinding()]
    param (
        [string[]]$UserPrincipalName,
        [switch]$StayConnected
    )
    begin {
        #Begining tests if the module is installed, loaded, and connected. Correcting each one at each level. 

        #Installs required modules
        Write-Verbose "Installing required modules"
        if (!(Get-InstallEdModule ExchangeOnlineManagement)) { 
            try {
                Install-Module ExchangeOnlineManagement
            }catch {
                Write-Error $_
                exit
            } 
        }
 
        Write-Verbose "Checking and importing required modules"
        # Starts importanting required modules
        if (!(Get-Command Connect-ExchangeOnline)) { 
            try {
                Import-Module ExchangeOnlineManagement
            } catch {
                Write-Error $_
                exit
            }
        }

        #Tests if Exchange Online is connected, If not, we trigger a connection
        if (!(Get-PSSession | Where-Object { $_.Name -match 'ExchangeOnline' -and $_.Availability -eq 'Available' })) { 
            try {
                Connect-ExchangeOnline}
            catch {
                Write-Error $_
                exit
            } 
        }
        if (!(Get-PSSession | Where-Object { $_.Name -match 'ExchangeOnline' -and $_.Availability -eq 'Available' })) {
            Write-Error "Connection failed"
            exit
        }
    }
    Process {
        $mailboxes = @()
        if (!($PSBoundParameters.ContainsKey("UserPrincipalName"))) {
            $Mailboxes = Get-mailbox
        }
        else {
            foreach ($Username in $UserPrincipalName) {
                try {
                    $Mailboxes += get-mailbox $username -ErrorAction SilentlyContinue
                }
                catch {
                    Write-Warning "$username has no mailbox"
                }
            }
        }

        #It has been proven to speed up the script if we drop the output into a return value
        $RulesReturn = Foreach ($Mail in $Mailboxes) {
            
            Write-Verbose "Scanning: $($Mail.UserPrincipalName)"
            #We are now trying to catch the rule in question. 
            #if the mailbox has no rules, which will be presented as an error, then we null out the rules. 
            try {
                $Rules = Get-InboxRule -Mailbox $Mail.Userprincipalname
            }
            catch {
                $Rules = $null  
            }

            #Now that the rules either have value or null, we can test. 
            if ($null -ne $Rules) {
                #Write-Host "$($mail.userprincipalname)"

                #Now we know we have rules, it's time to start working with those rules
                foreach ($Rule in $Rules) {

                    #From my testing I discover that some rules will be null but the rule itself isn't null. 
                    #Thus we need to test if this is the case. 
                    if ($null -ne $rule) {

                        #Now we have confirmed the rule is not empty, we need to test the form
                        #This is because some rules are based on subjects and such and not from people. 
                        if ($null -ne $rule.from) {
                            
                            #since form is not empty we split the string and we get the from information. 
                            $froms = $Rule.from.split('[')[0]
                        }
                        else {

                            #if it is, we just blank string the value. 
                            $froms = ""
                        }

                        #Next we want the description to be on a single line. this way we can export to a csv. 
                        if ($null -ne $rule.description) {

                            #This is programmed for the standard 5.1 powershell. Join-String was introduced in 6.2
                            #to combat this, we create a null return
                            #Then we  split the description rule. 
                            #Then we for each that list and push it back into the return.
                            
                            $dereturn = $Null
                            $rule.description.split("`n") | foreach-object { $dereturn = "$dereturn $($_.trim())" }
                            $description = $dereturn.trim()
                        }
                        else {
                            $description = ""
                        }
                        #Next we create our ps object with items we need for basic level audits. 
                        [pscustomobject]@{
                            Username    = $Mail.Userprincipalname
                            Identity    = $Rule.Identity
                            Enabled     = $Rule.Enabled
                            Name        = $Rule.Name
                            from        = $froms
                            Description = $description
                        } 
                    }
                }
            }
        }
    }
    end {

        #At the end we return
        $RulesReturn

        #Then we disconnect if the user didn't say stay connected. 
        if (!($StayConnected)) { Disconnect-ExchangeOnline -Confirm:$false }
    }
}

param (
        [string[]]$UserPrincipalName,
        [switch]$StayConnected
)

Write-Verbose "Installing required modules"
if (!(Get-InstallEdModule ExchangeOnlineManagement)) { 
        try {
            Install-Module ExchangeOnlineManagement
        }catch {
            Write-Error $_
            exit
        } 
}

Write-Verbose "Checking and importing required modules"
# Starts importanting required modules
if (!(Get-Command Connect-ExchangeOnline)) { 
    try {
        Import-Module ExchangeOnlineManagement
    } catch {
        Write-Error $_
        exit
    }
}

#Tests if Exchange Online is connected, If not, we trigger a connection
        if (!(Get-PSSession | Where-Object { $_.Name -match 'ExchangeOnline' -and $_.Availability -eq 'Available' })) { 
            try {
                Connect-ExchangeOnline}
            catch {
                Write-Error $_
                exit
            } 
        }
        if (!(Get-PSSession | Where-Object { $_.Name -match 'ExchangeOnline' -and $_.Availability -eq 'Available' })) {
            Write-Error "Connection failed"
            exit
        }

$mailboxes = @()

$mailboxes = @()
        if (!($PSBoundParameters.ContainsKey("UserPrincipalName"))) {
            $Mailboxes = Get-mailbox
        }
        else {
            foreach ($Username in $UserPrincipalName) {
                try {
                    $Mailboxes += get-mailbox $username -ErrorAction SilentlyContinue
                }
                catch {
                    Write-Warning "$username has no mailbox"
                }
            }
        }

$RulesReturn = Foreach ($Mail in $Mailboxes) {}

try {
    $Rules = Get-InboxRule -Mailbox $Mail.Userprincipalname
} catch {
    $Rules = $null  
}

if ($null -ne $Rules) {
    Write-Verbose "$($mail.userprincipalname)"
    foreach ($Rule in $Rules) {
        if ($null -ne $rule) {}
    }
}

if ($null -ne $rule.from) {
    $froms = $Rule.from.split('[')[0]
} else {
    $froms = ""
}

if ($null -ne $rule.description) {
    $dereturn = $Null
    $rule.description.split("`n") | foreach-object { $dereturn = "$dereturn $($_.trim())" }
    $description = $dereturn.trim()
} else {
    $description = ""
}

[pscustomobject]@{
    Username    = $Mail.Userprincipalname
    Identity    = $Rule.Identity
    Enabled     = $Rule.Enabled
    Name        = $Rule.Name
    from        = $froms
    Description = $description
} 

$RulesReturn
if (!($StayConnected)) { Disconnect-ExchangeOnline -Confirm:$false }