MainWindow.xaml

<Window x:Class="SpigenAudioCTRL.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        mc:Ignorable="d"
        Title="Spigen Audio CTRL" 
        Height="680" Width="1020"
        MinHeight="580" MinWidth="880"
        WindowStartupLocation="CenterScreen"
        Background="#0A0A0A"
        Foreground="#FFFFFF"
        FontFamily="Segoe UI Variable Display, Segoe UI Variable Text, Segoe UI, sans-serif">

    <WindowChrome.WindowChrome>
        <WindowChrome CaptionHeight="40"
                      ResizeBorderThickness="6"
                      CornerRadius="0"
                      GlassFrameThickness="0"
                      UseAeroCaptionButtons="False" />
    </WindowChrome.WindowChrome>

    <Grid Background="#0A0A0A">
        <Grid.RowDefinitions>
            <RowDefinition Height="40" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>

        <!-- TOP BAR: Refined Scandinavian TitleBar -->
        <Grid Grid.Row="0" Background="#0E0E0E">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*" />
                <ColumnDefinition Width="Auto" />
            </Grid.ColumnDefinitions>

            <!-- Left: App Identity & Live Status Pill -->
            <StackPanel Grid.Column="0" Orientation="Horizontal" VerticalAlignment="Center" Margin="16,0,0,0">
                <TextBlock Text="Spigen Audio CTRL" Foreground="#FFFFFF" FontWeight="SemiBold" FontSize="12.5" VerticalAlignment="Center" Margin="0,0,12,0"/>
                
                <Border Background="#141414" BorderBrush="#1AFFFFFF" BorderThickness="1" CornerRadius="10" Padding="8,2" VerticalAlignment="Center">
                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                        <Ellipse x:Name="tbStatusDot" Width="6" Height="6" Fill="#E63946" Margin="0,0,6,0"/>
                        <TextBlock x:Name="tbStatusText" Text="Connecting..." Foreground="#999999" FontSize="11"/>
                    </StackPanel>
                </Border>
            </StackPanel>

            <!-- Right: Caption Buttons -->
            <StackPanel Grid.Column="1" Orientation="Horizontal" WindowChrome.IsHitTestVisibleInChrome="True">
                <Button x:Name="btnMinimize" Style="{StaticResource CaptionButtonStyle}" Click="BtnMinimize_Click" Width="46" Height="40" ToolTip="Minimize">
                    <Path Data="M1,6 L11,6" Stroke="#999999" StrokeThickness="1" Width="10" Height="10" Stretch="Uniform"/>
                </Button>
                <Button x:Name="btnMaximize" Style="{StaticResource CaptionButtonStyle}" Click="BtnMaximize_Click" Width="46" Height="40" ToolTip="Maximize">
                    <Path x:Name="maximizeIcon" Data="M1.5,1.5 H10.5 V10.5 H1.5 Z" Stroke="#999999" StrokeThickness="1" Width="10" Height="10" Stretch="Uniform"/>
                </Button>
                <Button x:Name="btnClose" Style="{StaticResource CloseCaptionButtonStyle}" Click="BtnClose_Click" Width="46" Height="40" ToolTip="Close">
                    <Path Data="M2,2 L10,10 M10,2 L2,10" Stroke="#999999" StrokeThickness="1" Width="10" Height="10" Stretch="Uniform"/>
                </Button>
            </StackPanel>
        </Grid>

        <!-- MAIN APP BODY: 2-Column Scandinavian Layout -->
        <Grid Grid.Row="1">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="220" />
                <ColumnDefinition Width="*" />
            </Grid.ColumnDefinitions>

            <!-- LEFT SIDEBAR NAVIGATION RAIL -->
            <Border Grid.Column="0" Background="#0E0E0E" BorderBrush="#14FFFFFF" BorderThickness="0,0,1,0">
                <Grid>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto" />
                        <RowDefinition Height="*" />
                        <RowDefinition Height="Auto" />
                    </Grid.RowDefinitions>

                <!-- Device Info Card -->
                <Border Grid.Row="0" Margin="12,14,12,10" Background="#141414" BorderBrush="#1AFFFFFF" BorderThickness="1" CornerRadius="6" Padding="12,10">
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="Auto" />
                            <ColumnDefinition Width="*" />
                        </Grid.ColumnDefinitions>
                        <Border Width="28" Height="28" CornerRadius="4" Background="#1A1A1A" Margin="0,0,10,0">
                            <Path Data="M3,18 V12 A9,9 0 0,1 21,12 V18 A2,2 0 0,1 19,20 H18 A2,2 0 0,1 16,18 V15 A2,2 0 0,1 18,13 H21 V12 A9,9 0 0,0 3,12 V13 H6 A2,2 0 0,1 8,15 V18 A2,2 0 0,1 6,20 H5 A2,2 0 0,1 3,18 Z" 
                                  Stroke="#FFFFFF" StrokeThickness="1.2" Width="14" Height="14" Stretch="Uniform" VerticalAlignment="Center" HorizontalAlignment="Center"/>
                        </Border>
                        <StackPanel Grid.Column="1" VerticalAlignment="Center">
                            <TextBlock Text="Spigen SA-HP P10" Foreground="#FFFFFF" FontWeight="SemiBold" FontSize="12"/>
                            <TextBlock x:Name="txtDeviceSubtitle" Text="Bluetooth" Foreground="#777777" FontSize="10.5" Margin="0,1,0,0"/>
                            <!-- Fix #5 (audit): Battery level display - hidden until a level is received -->
                            <TextBlock x:Name="txtBatteryLevel" Text="" Foreground="#52B788" FontSize="10" FontWeight="SemiBold" Margin="0,2,0,0" Visibility="Collapsed"/>
                        </StackPanel>
                    </Grid>
                </Border>

                <!-- Navigation Rail Menu Items -->
                <StackPanel Grid.Row="1" Margin="6,6,6,0">
                    <!-- Noise Control: Sound Waveform -->
                    <RadioButton x:Name="navAnc" Style="{StaticResource NavRailItemStyle}" IsChecked="True" Checked="Nav_Checked">
                        <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                            <Path Data="M2,12 L5,5 L9,19 L13,3 L17,21 L21,8 L23,12" Stroke="#CCCCCC" StrokeThickness="1.3" Width="14" Height="14" Stretch="Uniform" Margin="0,0,10,0"/>
                            <TextBlock Text="Noise Control" VerticalAlignment="Center"/>
                        </StackPanel>
                    </RadioButton>

                    <!-- 10-Band Equalizer: Mixing Console Faders -->
                    <RadioButton x:Name="navEq" Style="{StaticResource NavRailItemStyle}" Checked="Nav_Checked">
                        <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                            <Path Data="M4,21 V14 M4,10 V3 M12,21 V12 M12,8 V3 M20,21 V16 M20,12 V3 M1,14 H7 M9,8 H15 M17,16 H23" Stroke="#CCCCCC" StrokeThickness="1.3" Width="14" Height="14" Stretch="Uniform" Margin="0,0,10,0"/>
                            <TextBlock Text="10-Band Equalizer" VerticalAlignment="Center"/>
                        </StackPanel>
                    </RadioButton>

                    <!-- Button Remapping: 3-Button Controller -->
                    <RadioButton x:Name="navButtons" Style="{StaticResource NavRailItemStyle}" Checked="Nav_Checked">
                        <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                            <Path Data="M5,6 H19 A3,3 0 0,1 22,9 V15 A3,3 0 0,1 19,18 H5 A3,3 0 0,1 2,15 V9 A3,3 0 0,1 5,6 Z M7.5,12 A1.5,1.5 0 1,1 7.5,11.99 Z M12,12 A1.5,1.5 0 1,1 12,11.99 Z M16.5,12 A1.5,1.5 0 1,1 16.5,11.99 Z" Stroke="#CCCCCC" StrokeThickness="1.2" Width="15" Height="15" Stretch="Uniform" Margin="0,0,10,0"/>
                            <TextBlock Text="Button Remapping" VerticalAlignment="Center"/>
                        </StackPanel>
                    </RadioButton>
                </StackPanel>

                <!-- Bottom Disconnect / Connect Button -->
                <Border Grid.Row="2" Padding="12,14" BorderBrush="#14FFFFFF" BorderThickness="0,1,0,0">
                    <Button x:Name="btnConnectAction" Style="{StaticResource NordicOutlineButtonStyle}" Click="BtnConnectAction_Click" HorizontalAlignment="Stretch" Height="34">
                        <StackPanel Orientation="Horizontal">
                            <Path Data="M18.36,6.64 A9,9 0 1,1 5.64,6.64 M12,2 V12" Stroke="#888888" StrokeThickness="1.3" Width="11" Height="11" Stretch="Uniform" Margin="0,0,8,0" VerticalAlignment="Center"/>
                            <TextBlock x:Name="txtConnectAction" Text="Disconnect" VerticalAlignment="Center"/>
                        </StackPanel>
                    </Button>
                </Border>
            </Grid>
        </Border>

        <!-- RIGHT MAIN CONTENT VIEWPORT -->
            <Grid Grid.Column="1" Background="#0A0A0A" Margin="28,22,28,24">

                <!-- ==================== TAB 1: NOISE CONTROL ==================== -->
                <Grid x:Name="panelAnc" Visibility="Visible">
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto" />
                        <RowDefinition Height="Auto" />
                        <RowDefinition Height="Auto" />
                    </Grid.RowDefinitions>

                    <!-- Section Header -->
                    <StackPanel Grid.Row="0" Margin="0,0,0,20">
                        <TextBlock Text="Noise Control" FontSize="18" FontWeight="SemiBold" Foreground="#FFFFFF"/>
                        <TextBlock Text="Select active acoustic isolation or ambient transparency profile" FontSize="12.5" Foreground="#888888" Margin="0,3,0,0"/>
                    </StackPanel>

                    <!-- 2x3 Grid of ANC Mode Tiles -->
                    <Grid Grid.Row="1">
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto" />
                            <RowDefinition Height="Auto" />
                        </Grid.RowDefinitions>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                        </Grid.ColumnDefinitions>

                        <!-- Deep ANC -->
                        <RadioButton Grid.Row="0" Grid.Column="0" x:Name="ancDeep" Style="{StaticResource NordicAncTileStyle}" Checked="AncMode_Checked">
                            <StackPanel>
                                <Grid Margin="0,0,0,6">
                                    <TextBlock Text="Deep ANC" FontWeight="SemiBold" FontSize="13" Foreground="#FFFFFF"/>
                                    <Border HorizontalAlignment="Right" Background="#1C1C1C" CornerRadius="4" Padding="6,2">
                                        <TextBlock Text="-43 dB" FontSize="10" FontWeight="SemiBold" Foreground="#CCCCCC"/>
                                    </Border>
                                </Grid>
                                <TextBlock Text="Maximum isolation for flights, transit, and loud environments." Foreground="#777777" FontSize="11" TextWrapping="Wrap"/>
                            </StackPanel>
                        </RadioButton>

                        <!-- Adaptive ANC -->
                        <RadioButton Grid.Row="0" Grid.Column="1" x:Name="ancAdaptive" Style="{StaticResource NordicAncTileStyle}" IsChecked="True" Checked="AncMode_Checked">
                            <StackPanel>
                                <Grid Margin="0,0,0,6">
                                    <TextBlock Text="Adaptive ANC" FontWeight="SemiBold" FontSize="13" Foreground="#FFFFFF"/>
                                    <Border HorizontalAlignment="Right" Background="#1C1C1C" CornerRadius="4" Padding="6,2">
                                        <TextBlock Text="Dynamic" FontSize="10" FontWeight="SemiBold" Foreground="#CCCCCC"/>
                                    </Border>
                                </Grid>
                                <TextBlock Text="Dynamically recalculates filter strength based on real-time ear seal." Foreground="#777777" FontSize="11" TextWrapping="Wrap"/>
                            </StackPanel>
                        </RadioButton>

                        <!-- Commuting -->
                        <RadioButton Grid.Row="0" Grid.Column="2" x:Name="ancCommuting" Style="{StaticResource NordicAncTileStyle}" Checked="AncMode_Checked">
                            <StackPanel>
                                <Grid Margin="0,0,0,6">
                                    <TextBlock Text="Commuting" FontWeight="SemiBold" FontSize="13" Foreground="#FFFFFF"/>
                                    <Border HorizontalAlignment="Right" Background="#1C1C1C" CornerRadius="4" Padding="6,2">
                                        <TextBlock Text="Transit" FontSize="10" FontWeight="SemiBold" Foreground="#888888"/>
                                    </Border>
                                </Grid>
                                <TextBlock Text="Targets low-frequency vehicle rumble on trains and buses." Foreground="#777777" FontSize="11" TextWrapping="Wrap"/>
                            </StackPanel>
                        </RadioButton>

                        <!-- Anti-Wind -->
                        <RadioButton Grid.Row="1" Grid.Column="0" x:Name="ancAntiWind" Style="{StaticResource NordicAncTileStyle}" Checked="AncMode_Checked">
                            <StackPanel>
                                <Grid Margin="0,0,0,6">
                                    <TextBlock Text="Anti-Wind" FontWeight="SemiBold" FontSize="13" Foreground="#FFFFFF"/>
                                    <Border HorizontalAlignment="Right" Background="#1C1C1C" CornerRadius="4" Padding="6,2">
                                        <TextBlock Text="Outdoor" FontSize="10" FontWeight="SemiBold" Foreground="#888888"/>
                                    </Border>
                                </Grid>
                                <TextBlock Text="Suppresses turbulence across external feed-forward microphones." Foreground="#777777" FontSize="11" TextWrapping="Wrap"/>
                            </StackPanel>
                        </RadioButton>

                        <!-- Transparency -->
                        <RadioButton Grid.Row="1" Grid.Column="1" x:Name="ancTransparency" Style="{StaticResource NordicAncTileStyle}" Checked="AncMode_Checked">
                            <StackPanel>
                                <Grid Margin="0,0,0,6">
                                    <TextBlock Text="Transparency" FontWeight="SemiBold" FontSize="13" Foreground="#FFFFFF"/>
                                    <Border HorizontalAlignment="Right" Background="#1C1C1C" CornerRadius="4" Padding="6,2">
                                        <TextBlock Text="Ambient" FontSize="10" FontWeight="SemiBold" Foreground="#CCCCCC"/>
                                    </Border>
                                </Grid>
                                <TextBlock Text="Natural environmental awareness and conversation pass-through." Foreground="#777777" FontSize="11" TextWrapping="Wrap"/>
                            </StackPanel>
                        </RadioButton>

                        <!-- Off (Passive) -->
                        <RadioButton Grid.Row="1" Grid.Column="2" x:Name="ancOff" Style="{StaticResource NordicAncTileStyle}" Checked="AncMode_Checked">
                            <StackPanel>
                                <Grid Margin="0,0,0,6">
                                    <TextBlock Text="Off (Passive)" FontWeight="SemiBold" FontSize="13" Foreground="#FFFFFF"/>
                                    <Border HorizontalAlignment="Right" Background="#1C1C1C" CornerRadius="4" Padding="6,2">
                                        <TextBlock Text="Passive" FontSize="10" FontWeight="SemiBold" Foreground="#888888"/>
                                    </Border>
                                </Grid>
                                <TextBlock Text="Disables ANC microphones for maximum battery life (~60 hours)." Foreground="#777777" FontSize="11" TextWrapping="Wrap"/>
                            </StackPanel>
                        </RadioButton>
                    </Grid>

                    <!-- Low Latency Switch Row -->
                    <Border Grid.Row="2" Margin="4,16,4,0" Background="#141414" BorderBrush="#1AFFFFFF" BorderThickness="1" CornerRadius="6" Padding="16,14">
                        <Grid>
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="*" />
                                <ColumnDefinition Width="Auto" />
                            </Grid.ColumnDefinitions>
                            <StackPanel Grid.Column="0" VerticalAlignment="Center">
                                <TextBlock Text="Low-Latency Gaming Mode" FontSize="13" FontWeight="SemiBold" Foreground="#FFFFFF"/>
                                <TextBlock Text="Reduces wireless audio transmission delay to ~45ms" FontSize="11.5" Foreground="#777777" Margin="0,2,0,0"/>
                            </StackPanel>
                            <CheckBox Grid.Column="1" x:Name="chkGamingMode" Style="{StaticResource NordicToggleSwitchStyle}" Click="ChkGamingMode_Click"/>
                        </Grid>
                    </Border>
                </Grid>

                <!-- ==================== TAB 2: 10-BAND EQUALIZER ==================== -->
                <Grid x:Name="panelEq" Visibility="Collapsed">
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto" />
                        <RowDefinition Height="165" />
                        <RowDefinition Height="Auto" />
                        <RowDefinition Height="Auto" />
                    </Grid.RowDefinitions>

                    <!-- Header & Preset Controls -->
                    <Grid Grid.Row="0" Margin="0,0,0,16">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="Auto" />
                        </Grid.ColumnDefinitions>
                        <StackPanel Grid.Column="0" VerticalAlignment="Center">
                            <TextBlock Text="10-Band DSP Equalizer" FontSize="18" FontWeight="SemiBold" Foreground="#FFFFFF"/>
                            <TextBlock Text="Fine-tune 16-bit parametric hardware filters stored on-chip" FontSize="12.5" Foreground="#888888" Margin="0,3,0,0"/>
                        </StackPanel>
                        <StackPanel Grid.Column="1" Orientation="Horizontal" VerticalAlignment="Center">
                            <ComboBox x:Name="cmbEqPresets" Style="{StaticResource NordicComboBoxStyle}" Width="190" Margin="0,0,8,0" SelectionChanged="CmbEqPresets_SelectionChanged"/>
                            <Button x:Name="btnSavePreset" Style="{StaticResource NordicButtonStyle}" Content="Save" Margin="0,0,6,0" Click="BtnSavePreset_Click"/>
                            <Button x:Name="btnResetEq" Style="{StaticResource NordicButtonStyle}" Content="Reset" Click="BtnResetEq_Click"/>
                        </StackPanel>
                    </Grid>

                    <!-- Dynamic Bezier Curve Canvas -->
                    <Border Grid.Row="1" Background="#0E0E0E" BorderBrush="#1AFFFFFF" BorderThickness="1" CornerRadius="6" ClipToBounds="True">
                        <Canvas x:Name="eqCanvas" SizeChanged="EqCanvas_SizeChanged" MouseDown="EqCanvas_MouseDown" MouseMove="EqCanvas_MouseMove" MouseUp="EqCanvas_MouseUp"/>
                    </Border>

                    <!-- 10 Vertical Sliders Rack -->
                    <Border Grid.Row="2" Margin="0,10,0,0" Background="#141414" BorderBrush="#1AFFFFFF" BorderThickness="1" CornerRadius="6" Padding="6,12">
                        <UniformGrid x:Name="eqSlidersGrid" Columns="10" Height="165"/>
                    </Border>

                    <!-- Harman Target Reference Toggle -->
                    <Grid Grid.Row="3" Margin="0,12,0,0">
                        <CheckBox x:Name="chkHarmanTarget" Content="Show Harman Target 2019 reference curve" IsChecked="True" Foreground="#888888" FontSize="12" Click="ChkHarmanTarget_Click">
                            <CheckBox.Template>
                                <ControlTemplate TargetType="CheckBox">
                                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center" Cursor="Hand">
                                        <Ellipse Width="8" Height="8" Fill="#E5A93C" Margin="0,0,8,0"/>
                                        <ContentPresenter VerticalAlignment="Center"/>
                                    </StackPanel>
                                </ControlTemplate>
                            </CheckBox.Template>
                        </CheckBox>
                    </Grid>
                </Grid>

                <!-- ==================== TAB 3: BUTTON REMAPPING ==================== -->
                <Grid x:Name="panelButtons" Visibility="Collapsed">
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto" />
                        <RowDefinition Height="*" />
                    </Grid.RowDefinitions>

                    <StackPanel Grid.Row="0" Margin="0,0,0,16">
                        <TextBlock Text="Button Remapping" FontSize="18" FontWeight="SemiBold" Foreground="#FFFFFF"/>
                        <TextBlock Text="Customize gestures and physical key actions stored in headphone memory" FontSize="12.5" Foreground="#888888" Margin="0,3,0,0"/>
                    </StackPanel>

                    <!-- Grouped Settings Table -->
                    <Border Grid.Row="1" Background="#141414" BorderBrush="#1AFFFFFF" BorderThickness="1" CornerRadius="6" Padding="14,6">
                        <ScrollViewer VerticalScrollBarVisibility="Auto">
                            <StackPanel x:Name="buttonRemapList"/>
                        </ScrollViewer>
                    </Border>
                </Grid>

            </Grid>
        </Grid>
    </Grid>
</Window>