class StartupParameters
{
    [System.UInt32[]]
    $TraceFlag

    static [StartupParameters] Parse([System.String] $InstanceStartupParameters)
    {
        $startupParameters = [StartupParameters]::new()

        $startupParameterValues = $InstanceStartupParameters -split ';'

        $startupParameters.TraceFlag = [System.UInt32[]] @(
            $startupParameterValues |
                Where-Object -FilterScript {
                    $_ -match '^-T\d+'
                } |
                ForEach-Object -Process {
                    [System.UInt32] $_.TrimStart('-T')
                }
        )

        return $startupParameters
    }
}

function Get-SqlDscTraceFlag
{
    [OutputType([System.UInt32[]])]
    [CmdletBinding(DefaultParameterSetName = 'ByServerName')]
    param
    (
        [Parameter(ParameterSetName = 'ByServiceObject', Mandatory = $true)]
        [Object]
        $ServiceObject
    )

    $traceFlags = [System.UInt32[]] @()

    if ($ServiceObject.StartupParameters)
    {
        $traceFlags = [StartupParameters]::Parse($ServiceObject.StartupParameters).TraceFlag
    }

    return , [System.UInt32[]] $traceFlags
}

BeforeAll {
    Import-Module -Name './SqlServerDsc.psm1' -Force
}

AfterAll {
    # Unload the module being tested so that it doesn't impact any other tests.
    Get-Module -Name 'SqlServerDsc' -All | Remove-Module -Force
}

Describe 'SqlServerDsc' {
    Context 'When one trace flag exist' {
        BeforeAll {
            $mockStartupParameters = '-T4199'

            $mockServiceObject = [PSCustomObject] @{
                StartupParameters = $mockStartupParameters
            }
        }

        Context 'When passing a service object' {
            It 'Should return the correct values' {
                $result = Get-SqlDscTraceFlag -ServiceObject $mockServiceObject

                $result | Should -HaveCount 1
                $result | Should -Contain 4199
            }
        }
    }
}

$pesterConfig = New-PesterConfiguration -Hashtable @{
    CodeCoverage = @{
        Enabled = $true
        Path = './SqlServerDsc.psm1'
        OutputPath = './Pester_coverage.xml'
        # Tests fails if this is $false
        UseBreakpoints = $false
    }
    Run = @{
        Path = '*.Tests.ps1'
    }
}

$Error.Clear()
$ErrorView = 'DetailedView'

Invoke-Pester -Configuration $pesterConfig

$Error

Pester version     : 5.4.0 C:\source\SqlServerDsc\output\RequiredModules\Pester\5.4.0\Pester.psm1                       
PowerShell version : 7.3.2
OS version         : Microsoft Windows NT 10.0.22623.0