DscResource.Common.psm1

$script:modulesFolderPath = Split-Path -Path $PSScriptRoot -Parent

<#
    .SYNOPSIS
        This method is used to compare current and desired values for any DSC resource.

    .PARAMETER CurrentValues
        This is hash table of the current values that are applied to the resource.

    .PARAMETER DesiredValues
        This is a PSBoundParametersDictionary of the desired values for the resource.

    .PARAMETER ValuesToCheck
        This is a list of which properties in the desired values list should be checked.
        If this is empty then all values in DesiredValues are checked.
#>
function Test-DscParameterState
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [System.Collections.Hashtable]
        $CurrentValues,

        [Parameter(Mandatory = $true)]
        [System.Object]
        $DesiredValues,

        [Parameter()]
        [System.Array]
        $ValuesToCheck
    )

    $returnValue = $true

    if (($DesiredValues.GetType().Name -ne 'HashTable') `
        -and ($DesiredValues.GetType().Name -ne 'CimInstance') `
        -and ($DesiredValues.GetType().Name -ne 'PSBoundParametersDictionary'))
    {
        $errorMessage = $script:localizedData.PropertyTypeInvalidForDesiredValues -f $($DesiredValues.GetType().Name)
        New-InvalidArgumentException -ArgumentName 'DesiredValues' -Message $errorMessage
    }

    if (($DesiredValues.GetType().Name -eq 'CimInstance') -and ($null -eq $ValuesToCheck))
    {
        $errorMessage = $script:localizedData.PropertyTypeInvalidForValuesToCheck
        New-InvalidArgumentException -ArgumentName 'ValuesToCheck' -Message $errorMessage
    }

    if (($null -eq $ValuesToCheck) -or ($ValuesToCheck.Count -lt 1))
    {
        $keyList = $DesiredValues.Keys
    }
    else
    {
        $keyList = $ValuesToCheck
    }

    $keyList | ForEach-Object -Process {
        if (($_ -ne 'Verbose'))
        {
            if (($CurrentValues.ContainsKey($_) -eq $false) `
            -or ($CurrentValues.$_ -ne $DesiredValues.$_) `
            -or (($DesiredValues.GetType().Name -ne 'CimInstance' -and $DesiredValues.ContainsKey($_) -eq $true) -and ($null -ne $DesiredValues.$_ -and $DesiredValues.$_.GetType().IsArray)))
            {
                if ($DesiredValues.GetType().Name -eq 'HashTable' -or `
                    $DesiredValues.GetType().Name -eq 'PSBoundParametersDictionary')
                {
                    $checkDesiredValue = $DesiredValues.ContainsKey($_)
                }
                else
                {
                    # If DesiredValue is a CimInstance.
                    $checkDesiredValue = $false
                    if (([System.Boolean]($DesiredValues.PSObject.Properties.Name -contains $_)) -eq $true)
                    {
                        if ($null -ne $DesiredValues.$_)
                        {
                            $checkDesiredValue = $true
                        }
                    }
                }

                if ($checkDesiredValue)
                {
                    $desiredType = $DesiredValues.$_.GetType()
                    $fieldName = $_
                    if ($desiredType.IsArray -eq $true)
                    {
                        if (($CurrentValues.ContainsKey($fieldName) -eq $false) `
                        -or ($null -eq $CurrentValues.$fieldName))
                        {
                            Write-Verbose -Message ($script:localizedData.PropertyValidationError -f $fieldName) -Verbose

                            $returnValue = $false
                        }
                        else
                        {
                            $arrayCompare = Compare-Object -ReferenceObject $CurrentValues.$fieldName `
                                                           -DifferenceObject $DesiredValues.$fieldName
                            if ($null -ne $arrayCompare)
                            {
                                Write-Verbose -Message ($script:localizedData.PropertiesDoesNotMatch -f $fieldName) -Verbose

                                $arrayCompare | ForEach-Object -Process {
                                    Write-Verbose -Message ($script:localizedData.PropertyThatDoesNotMatch -f $_.InputObject, $_.SideIndicator) -Verbose
                                }

                                $returnValue = $false
                            }
                        }
                    }
                    else
                    {
                        switch ($desiredType.Name)
                        {
                            'String'
                            {
                                if (-not [System.String]::IsNullOrEmpty($CurrentValues.$fieldName) -or `
                                    -not [System.String]::IsNullOrEmpty($DesiredValues.$fieldName))
                                {
                                    Write-Verbose -Message ($script:localizedData.ValueOfTypeDoesNotMatch `
                                        -f $desiredType.Name, $fieldName, $($CurrentValues.$fieldName), $($DesiredValues.$fieldName)) -Verbose

                                    $returnValue = $false
                                }
                            }

                            'Int32'
                            {
                                if (-not ($DesiredValues.$fieldName -eq 0) -or `
                                    -not ($null -eq $CurrentValues.$fieldName))
                                {
                                    Write-Verbose -Message ($script:localizedData.ValueOfTypeDoesNotMatch `
                                        -f $desiredType.Name, $fieldName, $($CurrentValues.$fieldName), $($DesiredValues.$fieldName)) -Verbose

                                    $returnValue = $false
                                }
                            }

                            { $_ -eq 'Int16' -or $_ -eq 'UInt16' -or $_ -eq 'Single' }
                            {
                                if (-not ($DesiredValues.$fieldName -eq 0) -or `
                                    -not ($null -eq $CurrentValues.$fieldName))
                                {
                                    Write-Verbose -Message ($script:localizedData.ValueOfTypeDoesNotMatch `
                                        -f $desiredType.Name, $fieldName, $($CurrentValues.$fieldName), $($DesiredValues.$fieldName)) -Verbose

                                    $returnValue = $false
                                }
                            }

                            'Boolean'
                            {
                                if ($CurrentValues.$fieldName -ne $DesiredValues.$fieldName)
                                {
                                    Write-Verbose -Message ($script:localizedData.ValueOfTypeDoesNotMatch `
                                        -f $desiredType.Name, $fieldName, $($CurrentValues.$fieldName), $($DesiredValues.$fieldName)) -Verbose

                                    $returnValue = $false
                                }
                            }

                            default
                            {
                                Write-Warning -Message ($script:localizedData.UnableToCompareProperty `
                                    -f $fieldName, $desiredType.Name)

                                $returnValue = $false
                            }
                        }
                    }
                }
            }
        }
    }

    return $returnValue
}

<#
    .SYNOPSIS
        Retrieves the localized string data based on the machine's culture.
        Falls back to en-US strings if the machine's culture is not supported.

    .PARAMETER ResourceName
        The name of the resource as it appears before '.strings.psd1' of the localized string file.
        For example:
            For WindowsOptionalFeature: MSFT_WindowsOptionalFeature
            For Service: MSFT_ServiceResource
            For Registry: MSFT_RegistryResource
            For Helper: SqlServerDscHelper

    .PARAMETER ScriptRoot
        Optional. The root path where to expect to find the culture folder. This is only needed
        for localization in helper modules. This should not normally be used for resources.

    .NOTES
        To be able to use localization in the helper function, this function must
        be first in the file, before Get-LocalizedData is used by itself to load
        localized data for this helper module (see directly after this function).
#>
function Get-LocalizedData
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $ResourceName,

        [Parameter()]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $ScriptRoot
    )

    if (-not $ScriptRoot)
    {
        $dscResourcesFolder = Join-Path -Path (Split-Path -Path (Split-Path -Path $PSScriptRoot -Parent) -Parent) -ChildPath 'DSCResources'
        $resourceDirectory = Join-Path -Path $dscResourcesFolder -ChildPath $ResourceName
    }
    else
    {
        $resourceDirectory = $ScriptRoot
    }

    $localizedStringFileLocation = Join-Path -Path $resourceDirectory -ChildPath $PSUICulture

    if (-not (Test-Path -Path $localizedStringFileLocation))
    {
        # Fallback to en-US
        $localizedStringFileLocation = Join-Path -Path $resourceDirectory -ChildPath 'en-US'
    }

    Import-LocalizedData `
        -BindingVariable 'localizedData' `
        -FileName "$ResourceName.strings.psd1" `
        -BaseDirectory $localizedStringFileLocation

    return $localizedData
}

<#
    .SYNOPSIS
        Creates and throws an invalid argument exception.

    .PARAMETER Message
        The message explaining why this error is being thrown.

    .PARAMETER ArgumentName
        The name of the invalid argument that is causing this error to be thrown.
#>
function New-InvalidArgumentException
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $Message,

        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $ArgumentName
    )

    $argumentException = New-Object -TypeName 'ArgumentException' `
        -ArgumentList @($Message, $ArgumentName)

    $newObjectParameters = @{
        TypeName     = 'System.Management.Automation.ErrorRecord'
        ArgumentList = @($argumentException, $ArgumentName, 'InvalidArgument', $null)
    }

    $errorRecord = New-Object @newObjectParameters

    throw $errorRecord
}

<#
    .SYNOPSIS
        Creates and throws an invalid operation exception.

    .PARAMETER Message
        The message explaining why this error is being thrown.

    .PARAMETER ErrorRecord
        The error record containing the exception that is causing this terminating error.
#>
function New-InvalidOperationException
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $Message,

        [Parameter()]
        [ValidateNotNull()]
        [System.Management.Automation.ErrorRecord]
        $ErrorRecord
    )

    if ($null -eq $ErrorRecord)
    {
        $invalidOperationException = New-Object -TypeName 'InvalidOperationException' `
            -ArgumentList @($Message)
    }
    else
    {
        $invalidOperationException = New-Object -TypeName 'InvalidOperationException' `
            -ArgumentList @($Message, $ErrorRecord.Exception)
    }

    $newObjectParameters = @{
        TypeName     = 'System.Management.Automation.ErrorRecord'
        ArgumentList = @(
            $invalidOperationException.ToString(),
            'MachineStateIncorrect',
            'InvalidOperation',
            $null
        )
    }

    $errorRecordToThrow = New-Object @newObjectParameters

    throw $errorRecordToThrow
}

<#
    .SYNOPSIS
        Creates and throws an object not found exception.

    .PARAMETER Message
        The message explaining why this error is being thrown.

    .PARAMETER ErrorRecord
        The error record containing the exception that is causing this terminating error.
#>
function New-ObjectNotFoundException
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $Message,

        [Parameter()]
        [ValidateNotNull()]
        [System.Management.Automation.ErrorRecord]
        $ErrorRecord
    )

    if ($null -eq $ErrorRecord)
    {
        $exception = New-Object -TypeName 'System.Exception' `
            -ArgumentList @($Message)
    }
    else
    {
        $exception = New-Object -TypeName 'System.Exception' `
            -ArgumentList @($Message, $ErrorRecord.Exception)
    }

    $newObjectParameters = @{
        TypeName     = 'System.Management.Automation.ErrorRecord'
        ArgumentList = @(
            $exception.ToString(),
            'MachineStateIncorrect',
            'ObjectNotFound',
            $null
        )
    }

    $errorRecordToThrow = New-Object @newObjectParameters

    throw $errorRecordToThrow
}

<#
    .SYNOPSIS
        Creates and throws an invalid result exception.

    .PARAMETER Message
        The message explaining why this error is being thrown.

    .PARAMETER ErrorRecord
        The error record containing the exception that is causing this terminating error.
#>
function New-InvalidResultException
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $Message,

        [Parameter()]
        [ValidateNotNull()]
        [System.Management.Automation.ErrorRecord]
        $ErrorRecord
    )

    if ($null -eq $ErrorRecord)
    {
        $exception = New-Object -TypeName 'System.Exception' `
            -ArgumentList @($Message)
    }
    else
    {
        $exception = New-Object -TypeName 'System.Exception' `
            -ArgumentList @($Message, $ErrorRecord.Exception)
    }

    $newObjectParameters = @{
        TypeName     = 'System.Management.Automation.ErrorRecord'
        ArgumentList = @(
            $exception.ToString(),
            'MachineStateIncorrect',
            'InvalidResult',
            $null
        )
    }

    $errorRecordToThrow = New-Object @newObjectParameters

    throw $errorRecordToThrow
}

function New-NotImplementedException
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.String]
        $Message,

        [Parameter()]
        [ValidateNotNull()]
        [System.Management.Automation.ErrorRecord]
        $ErrorRecord
    )

    if ($null -eq $ErrorRecord)
    {
        $invalidOperationException = New-Object -TypeName 'NotImplementedException' `
            -ArgumentList @($Message)
    }
    else
    {
        $invalidOperationException = New-Object -TypeName 'NotImplementedException' `
            -ArgumentList @($Message, $ErrorRecord.Exception)
    }

    $newObjectParameters = @{
        TypeName     = 'System.Management.Automation.ErrorRecord'
        ArgumentList = @(
            $invalidOperationException.ToString(),
            'MachineStateIncorrect',
            'NotImplemented',
            $null
        )
    }

    $errorRecordToThrow = New-Object @newObjectParameters

    throw $errorRecordToThrow
}

$script:localizedData = Get-LocalizedData -ResourceName 'DscResource.Common' -ScriptRoot $PSScriptRoot

Export-ModuleMember -Function @(
    'Test-DscParameterState',
    'New-InvalidArgumentException',
    'New-InvalidOperationException',
    'New-ObjectNotFoundException',
    'New-InvalidResultException',
    'New-NotImplementedException'
    'Get-LocalizedData'
)