MainWindow.xaml

<Window x:Class="TodoExport.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Microsoft To Do Export" 
        Height="750" Width="950"
        MinHeight="650" MinWidth="800"
        Background="#F5F5F5"
        WindowStartupLocation="CenterScreen"
        Loaded="Window_Loaded">

    <Window.Resources>
        <!-- Primary Blue Button -->
        <Style x:Key="PrimaryButton" TargetType="Button">
            <Setter Property="Background" Value="#0078D4"/>
            <Setter Property="Foreground" Value="White"/>
            <Setter Property="FontSize" Value="14"/>
            <Setter Property="FontWeight" Value="SemiBold"/>
            <Setter Property="Padding" Value="24,14"/>
            <Setter Property="BorderThickness" Value="0"/>
            <Setter Property="Cursor" Value="Hand"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border x:Name="border" Background="{TemplateBinding Background}" 
                                CornerRadius="6" Padding="{TemplateBinding Padding}">
                            <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="True">
                                <Setter TargetName="border" Property="Background" Value="#106EBE"/>
                            </Trigger>
                            <Trigger Property="IsEnabled" Value="False">
                                <Setter TargetName="border" Property="Background" Value="#CCCCCC"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
        
        <!-- Secondary/Outline Button -->
        <Style x:Key="SecondaryButton" TargetType="Button">
            <Setter Property="Background" Value="Transparent"/>
            <Setter Property="Foreground" Value="#0078D4"/>
            <Setter Property="FontSize" Value="13"/>
            <Setter Property="Padding" Value="16,10"/>
            <Setter Property="BorderThickness" Value="1.5"/>
            <Setter Property="BorderBrush" Value="#0078D4"/>
            <Setter Property="Cursor" Value="Hand"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border x:Name="border" Background="{TemplateBinding Background}" 
                                BorderBrush="{TemplateBinding BorderBrush}"
                                BorderThickness="{TemplateBinding BorderThickness}"
                                CornerRadius="6" Padding="{TemplateBinding Padding}">
                            <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="True">
                                <Setter TargetName="border" Property="Background" Value="#E8F4FD"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
        
        <!-- Ghost Button -->
        <Style x:Key="GhostButton" TargetType="Button">
            <Setter Property="Background" Value="Transparent"/>
            <Setter Property="Foreground" Value="#666"/>
            <Setter Property="FontSize" Value="13"/>
            <Setter Property="Padding" Value="12,8"/>
            <Setter Property="BorderThickness" Value="0"/>
            <Setter Property="Cursor" Value="Hand"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border x:Name="border" Background="{TemplateBinding Background}" 
                                CornerRadius="4" Padding="{TemplateBinding Padding}">
                            <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="True">
                                <Setter TargetName="border" Property="Background" Value="#E8E8E8"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
        
        <!-- List Item Checkbox Style -->
        <Style x:Key="ListCheckBox" TargetType="CheckBox">
            <Setter Property="Background" Value="White"/>
            <Setter Property="Foreground" Value="#333"/>
            <Setter Property="FontSize" Value="14"/>
            <Setter Property="Padding" Value="12,14"/>
            <Setter Property="Cursor" Value="Hand"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="CheckBox">
                        <Border x:Name="border" Background="White" CornerRadius="6" 
                                Padding="{TemplateBinding Padding}" Margin="0,2">
                            <Grid>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="Auto"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                
                                <Border x:Name="checkBorder" Width="20" Height="20" 
                                        CornerRadius="4" BorderThickness="2" 
                                        BorderBrush="#CCC" Background="White"
                                        VerticalAlignment="Center">
                                    <TextBlock x:Name="checkMark" Text="✓" 
                                               FontSize="14" FontWeight="Bold"
                                               Foreground="White" 
                                               HorizontalAlignment="Center" 
                                               VerticalAlignment="Center"
                                               Visibility="Collapsed"/>
                                </Border>
                                
                                <ContentPresenter Grid.Column="1" Margin="12,0,0,0" 
                                                  VerticalAlignment="Center"/>
                            </Grid>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsChecked" Value="True">
                                <Setter TargetName="checkBorder" Property="Background" Value="#0078D4"/>
                                <Setter TargetName="checkBorder" Property="BorderBrush" Value="#0078D4"/>
                                <Setter TargetName="checkMark" Property="Visibility" Value="Visible"/>
                            </Trigger>
                            <Trigger Property="IsMouseOver" Value="True">
                                <Setter TargetName="border" Property="Background" Value="#F8F8F8"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
        
        <!-- Code Box for Device Code -->
        <Style x:Key="CodeBox" TargetType="Border">
            <Setter Property="Background" Value="#1A1A2E"/>
            <Setter Property="CornerRadius" Value="8"/>
            <Setter Property="Padding" Value="24,16"/>
        </Style>
    </Window.Resources>

    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>

        <!-- Header -->
        <Border Grid.Row="0" Background="White" Padding="28,18" BorderBrush="#E0E0E0" BorderThickness="0,0,0,1">
            <Grid>
                <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                    <TextBlock Text="✅" FontSize="28" VerticalAlignment="Center"/>
                    <StackPanel Margin="14,0,0,0">
                        <TextBlock x:Name="AppTitleText" Text="Microsoft To Do Export" FontSize="22" FontWeight="SemiBold" Foreground="#1A1A1A"/>
                        <TextBlock x:Name="AppSubtitleText" Text="Back up your tasks in various formats" FontSize="12" Foreground="#888" Margin="0,2,0,0"/>
                    </StackPanel>
                </StackPanel>
                
                <!-- Right Side: Language Switch + User Info -->
                <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" VerticalAlignment="Center">
                    <!-- Language Switch -->
                    <StackPanel Orientation="Horizontal" Margin="0,0,20,0">
                        <Button x:Name="LanguageDEButton" Content="DE" 
                                Style="{StaticResource SecondaryButton}" 
                                FontSize="12" Padding="14,8"
                                Click="LanguageDEButton_Click"/>
                        <Button x:Name="LanguageENButton" Content="EN" 
                                Style="{StaticResource PrimaryButton}" 
                                FontSize="12" Padding="14,8" Margin="8,0,0,0"
                                Click="LanguageENButton_Click"/>
                    </StackPanel>
                    
                    <!-- User Info -->
                    <StackPanel x:Name="UserPanel" Orientation="Horizontal" 
                                VerticalAlignment="Center" Visibility="Collapsed">
                        <Border Width="38" Height="38" CornerRadius="19" Background="#0078D4">
                            <TextBlock x:Name="UserInitial" Text="M" FontSize="16" FontWeight="SemiBold"
                                       Foreground="White" HorizontalAlignment="Center" VerticalAlignment="Center"/>
                        </Border>
                        <StackPanel Margin="12,0,0,0" VerticalAlignment="Center">
                            <TextBlock x:Name="UserNameText" FontSize="14" FontWeight="SemiBold" Foreground="#1A1A1A"/>
                            <TextBlock x:Name="LoggedInText" Text="Signed in" FontSize="11" Foreground="#107C10"/>
                        </StackPanel>
                        <Button x:Name="SignOutButton" Content="Sign out" 
                                Style="{StaticResource GhostButton}"
                                Margin="20,0,0,0"
                                Click="SignOutButton_Click"/>
                    </StackPanel>
                </StackPanel>
            </Grid>
        </Border>

        <!-- Main Content -->
        <Grid Grid.Row="1">
            
            <!-- LOGIN SECTION -->
            <Border x:Name="LoginSection" Background="White" Margin="40" CornerRadius="12" 
                    VerticalAlignment="Center" HorizontalAlignment="Center" Padding="60,50">
                <StackPanel HorizontalAlignment="Center" MaxWidth="400">
                    <Border Width="80" Height="80" CornerRadius="40" Background="#E8F4FD" Margin="0,0,0,24">
                        <TextBlock Text="🔐" FontSize="36" HorizontalAlignment="Center" VerticalAlignment="Center"/>
                    </Border>
                    <TextBlock x:Name="SignInTitleText" Text="Sign in with Microsoft" 
                               FontSize="24" FontWeight="SemiBold" 
                               HorizontalAlignment="Center" Foreground="#1A1A1A"/>
                    <TextBlock x:Name="SignInSubtitleText" Text="Sign in to back up and export&#x0a;your To-Do lists." 
                               FontSize="14" Foreground="#666" 
                               HorizontalAlignment="Center" Margin="0,12,0,32"
                               TextWrapping="Wrap" TextAlignment="Center" LineHeight="22"/>
                    
                    <Button x:Name="SignInButton" 
                            Content="Sign in" 
                            Style="{StaticResource PrimaryButton}"
                            FontSize="15" Padding="40,16"
                            HorizontalAlignment="Center"
                            Click="SignInButton_Click"/>
                    
                    <TextBlock x:Name="SignInHintText" Text="Supports Outlook.com, Hotmail, Live, and work accounts" 
                               FontSize="11" Foreground="#AAA" 
                               HorizontalAlignment="Center" Margin="0,20,0,0"/>
                </StackPanel>
            </Border>

            <!-- DEVICE CODE SECTION -->
            <Border x:Name="DeviceCodeSection" Background="White" Margin="40" CornerRadius="12" 
                    VerticalAlignment="Center" HorizontalAlignment="Center" Padding="60,50" Visibility="Collapsed">
                <StackPanel HorizontalAlignment="Center" MaxWidth="420">
                    <ProgressBar IsIndeterminate="True" Height="3" Width="200" 
                                 Foreground="#0078D4" Margin="0,0,0,24"/>
                    <TextBlock x:Name="BrowserLoginText" Text="Browser sign-in" 
                               FontSize="22" FontWeight="SemiBold" 
                               HorizontalAlignment="Center" Foreground="#1A1A1A"/>
                    <TextBlock x:Name="BrowserLoginHintText" Text="A browser has been opened. Enter&#x0a;this code there to sign in:" 
                               FontSize="14" Foreground="#666" 
                               HorizontalAlignment="Center" Margin="0,12,0,24"
                               TextWrapping="Wrap" TextAlignment="Center" LineHeight="22"/>
                    
                    <!-- Code Display -->
                    <Border Style="{StaticResource CodeBox}" HorizontalAlignment="Center">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock x:Name="DeviceCodeText" Text="XXXXXXXX" 
                                       FontSize="28" FontWeight="Bold" FontFamily="Consolas"
                                       Foreground="#4FC3F7" VerticalAlignment="Center"/>
                            <Button x:Name="CopyCodeButton" Content="📋" 
                                    Background="Transparent" BorderThickness="0"
                                    Foreground="#666" FontSize="18" 
                                    Margin="16,0,0,0" Cursor="Hand"
                                    ToolTip="Copy code"
                                    Click="CopyCodeButton_Click"/>
                        </StackPanel>
                    </Border>
                    
                    <Button x:Name="OpenBrowserButton" 
                            Content="Open browser again" 
                            Style="{StaticResource SecondaryButton}"
                            FontSize="12" Padding="16,8" Margin="0,20,0,0"
                            HorizontalAlignment="Center"
                            Click="OpenBrowserButton_Click"/>
                    
                    <Button x:Name="CancelLoginButton" Content="Cancel" 
                            Style="{StaticResource GhostButton}"
                            HorizontalAlignment="Center" Margin="0,16,0,0"
                            Click="CancelLoginButton_Click"/>
                </StackPanel>
            </Border>

            <!-- EXPORT SECTION -->
            <Grid x:Name="ExportSection" Margin="28,20" Visibility="Collapsed">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="*" MinWidth="350"/>
                    <ColumnDefinition Width="320"/>
                </Grid.ColumnDefinitions>
                
                <!-- Left: List Selection -->
                <Border Grid.Column="0" Background="White" CornerRadius="10" Margin="0,0,14,0">
                    <Grid>
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="*"/>
                        </Grid.RowDefinitions>
                        
                        <!-- Header -->
                        <Border Grid.Row="0" Padding="20,16" BorderBrush="#EEE" BorderThickness="0,0,0,1">
                            <Grid>
                                <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                                    <TextBlock x:Name="SelectListsText" Text="Select lists" FontSize="16" FontWeight="SemiBold" Foreground="#1A1A1A" VerticalAlignment="Center"/>
                                    <TextBlock x:Name="ListCount" FontSize="13" Foreground="#0078D4" 
                                               VerticalAlignment="Center" Margin="10,0,0,0"/>
                                </StackPanel>
                                <StackPanel Orientation="Horizontal" HorizontalAlignment="Right">
                                    <Button x:Name="SelectAllButton" Content="All" 
                                            Style="{StaticResource PrimaryButton}" 
                                            FontSize="12" Padding="14,8"
                                            Click="SelectAllButton_Click"/>
                                    <Button x:Name="SelectNoneButton" Content="None" 
                                            Style="{StaticResource SecondaryButton}" 
                                            FontSize="12" Padding="14,8" Margin="8,0,0,0"
                                            Click="SelectNoneButton_Click"/>
                                    <Button x:Name="RefreshButton" Content="🔄" 
                                            Style="{StaticResource GhostButton}"
                                            FontSize="14" Padding="8,6" Margin="8,0,0,0"
                                            ToolTip="Refresh lists"
                                            Click="RefreshButton_Click"/>
                                </StackPanel>
                            </Grid>
                        </Border>
                        
                        <!-- List -->
                        <ScrollViewer Grid.Row="1" VerticalScrollBarVisibility="Auto" Padding="12,8">
                            <StackPanel x:Name="ListsPanel"/>
                        </ScrollViewer>
                    </Grid>
                </Border>
                
                <!-- Right: Export Options -->
                <Border Grid.Column="1" Background="White" CornerRadius="10">
                    <StackPanel Margin="24,20">
                        <TextBlock x:Name="ExportOptionsText" Text="Export options" FontSize="16" FontWeight="SemiBold" Foreground="#1A1A1A" Margin="0,0,0,20"/>
                        
                        <!-- Selected Count -->
                        <Border Background="#F0F7FF" CornerRadius="8" Padding="16,14" Margin="0,0,0,20">
                            <StackPanel>
                                <TextBlock x:Name="SelectedText" Text="Selected" FontSize="11" Foreground="#666" FontWeight="SemiBold"/>
                                <StackPanel Orientation="Horizontal" Margin="0,4,0,0">
                                    <TextBlock x:Name="SelectedCount" Text="0" FontSize="28" FontWeight="Bold" Foreground="#0078D4"/>
                                    <TextBlock x:Name="SelectedLabel" Text=" lists" FontSize="14" Foreground="#666" VerticalAlignment="Bottom" Margin="0,0,0,4"/>
                                </StackPanel>
                            </StackPanel>
                        </Border>
                        
                        <!-- Format Selection -->
                        <TextBlock x:Name="FormatText" Text="Format" FontSize="13" Foreground="#666" Margin="0,0,0,8"/>
                        <ComboBox x:Name="FormatComboBox" Height="44" FontSize="14" Padding="12,0" SelectedIndex="0"
                                  SelectionChanged="FormatComboBox_SelectionChanged">
                            <ComboBoxItem x:Name="FormatExcelItem" Content="Excel (.xlsx)" Tag="Excel"/>
                            <ComboBoxItem x:Name="FormatTodoistCsvItem" Content="Todoist CSV (.csv)" Tag="TodoistCsv"/>
                            <ComboBoxItem x:Name="FormatJsonItem" Content="JSON (.json)" Tag="Json"/>
                            <ComboBoxItem x:Name="FormatTextItem" Content="Text (.txt)" Tag="Text"/>
                            <ComboBoxItem x:Name="FormatDetailedTextItem" Content="Detailed Text (.txt)" Tag="DetailedText"/>
                            <ComboBoxItem x:Name="FormatDetailedCsvItem" Content="Detailed CSV (.csv)" Tag="DetailedCsv"/>
                        </ComboBox>
                        
                        <!-- Format Description -->
                        <TextBlock x:Name="FormatDescription" 
                                   Text="Compatible with Todoist import function" 
                                   FontSize="11" Foreground="#888" Margin="0,6,0,0" TextWrapping="Wrap"/>
                        
                        <!-- Options -->
                        <CheckBox x:Name="IncludeCompletedCheckBox" 
                                  Content="Include completed tasks"
                                  IsChecked="True"
                                  Margin="0,20,0,0"
                                  FontSize="13"
                                  Foreground="#444"
                                  Cursor="Hand"/>
                        
                        <!-- Export Button -->
                        <Button x:Name="ExportButton"
                                Content="Export" 
                                Style="{StaticResource PrimaryButton}"
                                FontSize="15" Margin="0,28,0,0"
                                HorizontalAlignment="Stretch"
                                Click="ExportButton_Click"/>
                        
                        <TextBlock x:Name="ExportHint" 
                                   Text="Select at least one list" 
                                   FontSize="11" Foreground="#AAA" 
                                   HorizontalAlignment="Center" Margin="0,12,0,0"/>
                    </StackPanel>
                </Border>
            </Grid>
        </Grid>

        <!-- Status Bar -->
        <Border Grid.Row="2" Background="White" Padding="28,12" BorderBrush="#E0E0E0" BorderThickness="0,1,0,0">
            <Grid>
                <TextBlock x:Name="StatusText" Text="Ready" FontSize="12" Foreground="#888" VerticalAlignment="Center"/>
                <ProgressBar x:Name="LoadingBar" IsIndeterminate="True" Width="120" Height="3" 
                             HorizontalAlignment="Right" Visibility="Collapsed" Foreground="#0078D4"/>
            </Grid>
        </Border>
    </Grid>
</Window>