# the maximum time until restart
[int32] $MAXMINUTES = 30;
# used for displaying the timer label
[string] $LABEL_FMT = "Minuten bis zum Neustart (Fenster schließt in {0} Sekunden)";
# used for displaying time until reboot on the button
[string] $BUTTON_FMT = "Neustart in {0} Minute(n)";
# XAML that defines the WPF GUI
[xml] $XAML = @"
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Neustart dringend erforderlich" Height="200" Width="400" ResizeMode="NoResize"
        Topmost="True" WindowStartupLocation="CenterScreen" WindowStyle="None" ShowInTaskbar="False">
    <Grid>
        <Button Name="button" Content="Neustart in 30 Minuten" HorizontalAlignment="Center"
            VerticalAlignment="Bottom" Margin="30" Width="170" Height="25"/>
        <Slider Name="slider" HorizontalAlignment="Center" VerticalAlignment="Center"
            Margin="0,0,0,50" Width="300" Height="30" TickPlacement="BottomRight" Minimum="0"
            Maximum="30" Value="30"/>
        <Label Name="lbl1" Content="0" HorizontalAlignment="Center" VerticalAlignment="Center"
            Margin="0,40,290,50"/>
        <Label Name="lbl2" Content="30" HorizontalAlignment="Center" VerticalAlignment="Center"
            Margin="290,40,0,50"/>
        <Label Name="label" Content="Minuten bis zum Neustart (Fenster schließt in 60 Sekunden)"
            HorizontalAlignment="Center" VerticalAlignment="Center" Margin="10,0,0,110"/>
    </Grid>
</Window>
"@

[int32] $minutesUntilRestart = $MAXMINUTES;
[int32] $secondCount = 60;

# Initialization
try {
    Add-Type -AssemblyName PresentationFramework -ErrorAction Stop;
    Add-Type -AssemblyName PresentationCore -ErrorAction Stop;
    Add-Type -AssemblyName WindowsBase -ErrorAction Stop;
    Add-Type -AssemblyName System.Windows.Forms -ErrorAction Stop;
} catch {
    Log-Error
}

$window = [Windows.Markup.XamlReader]::Load(( New-Object System.Xml.XmlNodeReader( $XAML ) ));

$XAML.SelectNodes( "//*[@Name]" ) | ForEach-Object {
    Set-Variable -Name( $_.Name ) -Value $window.FindName( $_.Name ) -Scope Script;
};

# WPF Controls

# Timer that counts down from 1 minute
$timer = New-Object System.Windows.Forms.Timer;
$timer.Interval = 1000;

# the slider that can be used to change the desired reboot time
$slider.Add_ValueChanged({
    $value = [int] $slider.Value;
    if ( $value -eq 0 ) {
        $button.Content = "Jetzt Neustarten";
    } else {
        $button.Content = $BUTTON_FMT -f $value;
    }
    $script:minutesUntilRestart = $value;
})

# the 'accept' button
$button.Add_Click({
    $script:window.Close();
})

# WPF window functionality
$window.Add_Closed({
    $script:timer.Stop();
    $script:timer.Dispose();
    if ( $script:minutesUntilRestart -eq 0 ) {
        Restart-Computer -Force;
    } else {
        Schedule-PSTask $REBOOT_TASK $REBOOT_CMD $script:minutesUntilRestart;
    }
})

$window.Add_Loaded({
    $script:timer.Add_Tick({
        $newcount = $script:secondCount - 1;
        $label.Content = $LABEL_FMT -f $newcount;
        $script:secondCount = $newcount;
        if ( $newcount -le 0 ){
            $script:window.Close();
        }
    })
    $script:timer.Start();
})

# source Log-Error and Schedule-PSTask
. "$PSScriptRoot\Functions.ps1"

# this schedules a reboot with the Task Scheduler
Schedule-PSTask $REBOOT_TASK $REBOOT_CMD $MAXMINUTES;
$window.ShowDialog() | Out-Null;