#!powershell

# Copyright: 2019, rnsc(@rnsc) <github@rnsc.be>
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt

#AnsibleRequires -CSharpUtil Ansible.Basic
#AnsibleRequires -OSVersion 6.3

$spec = @{
    options = @{
        drive_letter = @{ type = "str"; required = $true }
        state = @{ type = "str"; choices = "absent", "present"; default = "present"; }
        settings = @{
            type = "dict"
            required = $false
            options = @{
                minimum_file_size = @{ type = "int"; default = 32768 }
                minimum_file_age_days = @{ type = "int"; default = 2 }
                no_compress = @{ type = "bool"; required = $false; default = $false }
                optimize_in_use_files = @{ type = "bool"; required = $false; default = $false }
                verify = @{ type = "bool"; required = $false; default = $false }
            }
        }
    }
    supports_check_mode = $true
}

$module = [Ansible.Basic.AnsibleModule]::Create($args, $spec)

$drive_letter = $module.Params.drive_letter
$state = $module.Params.state
$settings = $module.Params.settings

$module.Result.changed = $false
$module.Result.reboot_required = $false
$module.Result.msg = ""

function Set-DataDeduplication($volume, $state, $settings, $dedup_job) {

    $current_state = 'absent'

    try {
        $dedup_info = Get-DedupVolume -Volume "$($volume.DriveLetter):"
    }
    catch {
        $dedup_info = $null
    }

    if ($dedup_info.Enabled) {
        $current_state = 'present'
    }

    if ( $state -ne $current_state ) {
        if ( -not $module.CheckMode) {
            if ($state -eq 'present') {
                # Enable-DedupVolume -Volume <String>
                Enable-DedupVolume -Volume "$($volume.DriveLetter):"
            }
            elseif ($state -eq 'absent') {
                Disable-DedupVolume -Volume "$($volume.DriveLetter):"
            }
        }
        $module.Result.changed = $true
    }

    if ($state -eq 'present') {
        if ($null -ne $settings) {
            Set-DataDedupJobSetting -volume $volume -settings $settings
        }
    }
}

function Set-DataDedupJobSetting ($volume, $settings) {

    try {
        $dedup_info = Get-DedupVolume -Volume "$($volume.DriveLetter):"
    }
    catch {
        $dedup_info = $null
    }

    ForEach ($key in $settings.keys) {

        # See Microsoft documentation:
        # https://docs.microsoft.com/en-us/powershell/module/deduplication/set-dedupvolume?view=win10-ps

        $update_key = $key
        $update_value = $settings.$($key)
        # Transform Ansible style options to Powershell params
        $update_key = $update_key -replace ('_', '')

        if ($update_key -eq "MinimumFileSize" -and $update_value -lt 32768) {
            $update_value = 32768
        }

        $current_value = ($dedup_info | Select-Object -ExpandProperty $update_key)

        if ($update_value -ne $current_value) {
            $command_param = @{
                $($update_key) = $update_value
            }

            # Set-DedupVolume -Volume <String>`
            #                 -NoCompress <bool> `
            #                 -MinimumFileAgeDays <UInt32> `
            #                 -MinimumFileSize <UInt32> (minimum 32768)
            if ( -not $module.CheckMode ) {
                Set-DedupVolume -Volume "$($volume.DriveLetter):" @command_param
            }

            $module.Result.changed = $true
        }
    }

}

# Install required feature
$feature_name = "FS-Data-Deduplication"
if ( -not $module.CheckMode) {
    $feature = Install-WindowsFeature -Name $feature_name

    if ($feature.RestartNeeded -eq 'Yes') {
        $module.Result.reboot_required = $true
        $module.FailJson("$feature_name was installed but requires Windows to be rebooted to work.")
    }
}

$volume = Get-Volume -DriveLetter $drive_letter

Set-DataDeduplication -volume $volume -state $state -settings $settings -dedup_job $dedup_job

$module.ExitJson()