window.rs

use std::path::PathBuf;
use std::sync::atomic::{AtomicU32, Ordering};
use std::sync::{Mutex, MutexGuard};
use std::time::{Duration, SystemTime, UNIX_EPOCH};

use serde::{Deserialize, Serialize};
use windows::core::PCWSTR;
use windows::Win32::Foundation::*;
use windows::Win32::Graphics::Gdi::*;
use windows::Win32::System::LibraryLoader::{GetModuleFileNameW, GetModuleHandleW};
use windows::Win32::System::Registry::*;
use windows::Win32::System::Threading::CreateMutexW;
use windows::Win32::UI::Accessibility::HWINEVENTHOOK;
use windows::Win32::UI::HiDpi::*;
use windows::Win32::UI::Input::KeyboardAndMouse::{ReleaseCapture, SetCapture};
use windows::Win32::UI::Shell::ExtractIconExW;
use windows::Win32::UI::WindowsAndMessaging::*;

use crate::diagnose;
use crate::localization::{self, LanguageId, Strings};
use crate::models::UsageData;
use crate::native_interop::{
    self, Color, TIMER_COUNTDOWN, TIMER_POLL, TIMER_RESET_POLL, TIMER_UPDATE_CHECK,
    WM_APP_TRAY, WM_APP_USAGE_UPDATED,
};
use crate::tray_icon;
use crate::poller;
use crate::theme;
use crate::updater::{self, InstallChannel, ReleaseDescriptor, UpdateCheckResult};

/// Wrapper to make HWND sendable across threads (safe for PostMessage usage)
#[derive(Clone, Copy)]
struct SendHwnd(isize);

unsafe impl Send for SendHwnd {}

impl SendHwnd {
    fn from_hwnd(hwnd: HWND) -> Self {
        Self(hwnd.0 as isize)
    }
    fn to_hwnd(self) -> HWND {
        HWND(self.0 as *mut _)
    }
}

/// Shared application state
struct AppState {
    hwnd: SendHwnd,
    taskbar_hwnd: Option<HWND>,
    tray_notify_hwnd: Option<HWND>,
    win_event_hook: Option<HWINEVENTHOOK>,
    is_dark: bool,
    embedded: bool,
    language_override: Option<LanguageId>,
    language: LanguageId,
    install_channel: InstallChannel,

    session_percent: f64,
    session_text: String,
    weekly_percent: f64,
    weekly_text: String,

    data: Option<UsageData>,

    poll_interval_ms: u32,
    retry_count: u32,
    last_poll_ok: bool,
    update_status: UpdateStatus,
    last_update_check_unix: Option<u64>,

    tray_offset: i32,
    dragging: bool,
    drag_start_mouse_x: i32,
    drag_start_offset: i32,
    show_decimals: bool,

    widget_visible: bool,
}

#[derive(Clone, Debug)]
enum UpdateStatus {
    Idle,
    Checking,
    Applying,
    UpToDate,
    Available(ReleaseDescriptor),
}

const RETRY_BASE_MS: u32 = 30_000; // 30 seconds

const POLL_1_MIN: u32 = 60_000;
const POLL_5_MIN: u32 = 300_000;
const POLL_15_MIN: u32 = 900_000;
const POLL_1_HOUR: u32 = 3_600_000;

// Menu item IDs for update frequency
const IDM_FREQ_1MIN: u16 = 10;
const IDM_FREQ_5MIN: u16 = 11;
const IDM_FREQ_15MIN: u16 = 12;
const IDM_FREQ_1HOUR: u16 = 13;
const IDM_START_WITH_WINDOWS: u16 = 20;
const IDM_RESET_POSITION: u16 = 30;
const IDM_VERSION_ACTION: u16 = 31;
const IDM_LANG_SYSTEM: u16 = 40;
const IDM_LANG_ENGLISH: u16 = 41;
const IDM_LANG_SPANISH: u16 = 42;
const IDM_LANG_FRENCH: u16 = 43;
const IDM_LANG_GERMAN: u16 = 44;
const IDM_LANG_JAPANESE: u16 = 45;
const IDM_SHOW_DECIMALS: u16 = 50;

const DIVIDER_HIT_ZONE: i32 = 13; // LEFT_DIVIDER_W + DIVIDER_RIGHT_MARGIN

const WM_DPICHANGED_MSG: u32 = 0x02E0;
const WM_APP_UPDATE_CHECK_COMPLETE: u32 = WM_APP + 2;

/// Current system DPI (96 = 100% scaling, 144 = 150%, 192 = 200%, etc.)
static CURRENT_DPI: AtomicU32 = AtomicU32::new(96);

/// Scale a base pixel value (designed at 96 DPI) to the current DPI.
fn sc(px: i32) -> i32 {
    let dpi = CURRENT_DPI.load(Ordering::Relaxed);
    (px as f64 * dpi as f64 / 96.0).round() as i32
}

/// Re-query the monitor DPI for our window and update the cached value.
/// Uses GetDpiForWindow which returns the live DPI (unlike GetDpiForSystem
/// which is cached at process startup and never changes).
fn refresh_dpi() {
    let hwnd = {
        let state = lock_state();
        state.as_ref().map(|s| s.hwnd.to_hwnd())
    };
    if let Some(hwnd) = hwnd {
        let dpi = unsafe { GetDpiForWindow(hwnd) };
        if dpi > 0 {
            CURRENT_DPI.store(dpi, Ordering::Relaxed);
        }
    }
}

fn load_embedded_app_icons() -> (HICON, HICON) {
    unsafe {
        let mut exe_buf = [0u16; 260];
        let len = GetModuleFileNameW(None, &mut exe_buf) as usize;
        if len == 0 {
            return (HICON::default(), HICON::default());
        }

        let mut large_icon = HICON::default();
        let mut small_icon = HICON::default();
        let extracted = ExtractIconExW(
            PCWSTR::from_raw(exe_buf.as_ptr()),
            0,
            Some(&mut large_icon),
            Some(&mut small_icon),
            1,
        );

        if extracted == 0 {
            (HICON::default(), HICON::default())
        } else {
            (large_icon, small_icon)
        }
    }
}

unsafe impl Send for AppState {}

static STATE: Mutex<Option<AppState>> = Mutex::new(None);

/// Lock STATE safely, recovering from poisoned mutex
fn lock_state() -> MutexGuard<'static, Option<AppState>> {
    STATE.lock().unwrap_or_else(|e| e.into_inner())
}

fn settings_path() -> PathBuf {
    let appdata = std::env::var("APPDATA").unwrap_or_else(|_| ".".to_string());
    PathBuf::from(appdata)
        .join("ClaudeCodeUsageMonitor")
        .join("settings.json")
}

#[derive(Debug, Serialize, Deserialize)]
struct SettingsFile {
    #[serde(default)]
    tray_offset: i32,
    #[serde(default = "default_poll_interval")]
    poll_interval_ms: u32,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    language: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    last_update_check_unix: Option<u64>,
    #[serde(default)]
    show_decimals: bool,
    #[serde(default = "default_widget_visible")]
    widget_visible: bool,
}

impl Default for SettingsFile {
    fn default() -> Self {
        Self {
            tray_offset: 0,
            poll_interval_ms: default_poll_interval(),
            language: None,
            last_update_check_unix: None,
            show_decimals: true,
            widget_visible: true,
        }
    }
}

fn default_poll_interval() -> u32 {
    POLL_15_MIN
}

fn default_widget_visible() -> bool {
    true
}

fn load_settings() -> SettingsFile {
    let content = match std::fs::read_to_string(settings_path()) {
        Ok(c) => c,
        Err(_) => return SettingsFile::default(),
    };
    serde_json::from_str(&content).unwrap_or_default()
}

fn save_settings(settings: &SettingsFile) {
    let path = settings_path();
    if let Some(parent) = path.parent() {
        let _ = std::fs::create_dir_all(parent);
    }
    if let Ok(json) = serde_json::to_string_pretty(settings) {
        let _ = std::fs::write(path, json);
    }
}

fn save_state_settings() {
    let state = lock_state();
    if let Some(s) = state.as_ref() {
        save_settings(&SettingsFile {
            tray_offset: s.tray_offset,
            poll_interval_ms: s.poll_interval_ms,
            language: s
                .language_override
                .map(|language| language.code().to_string()),
            last_update_check_unix: s.last_update_check_unix,
            show_decimals: s.show_decimals,
            widget_visible: s.widget_visible,
        });
    }
}

fn tray_icon_data_from_state() -> (Option<f64>, String) {
    let state = lock_state();
    match state.as_ref() {
        Some(s) if s.last_poll_ok => {
            let tooltip = format!("5h: {} | 7d: {}", s.session_text, s.weekly_text);
            (Some(s.session_percent), tooltip)
        }
        _ => (None, "Claude Code Usage Monitor".to_string()),
    }
}

fn toggle_widget_visibility(hwnd: HWND) {
    let new_visible = {
        let mut state = lock_state();
        if let Some(s) = state.as_mut() {
            s.widget_visible = !s.widget_visible;
            s.widget_visible
        } else {
            return;
        }
    };
    save_state_settings();
    unsafe {
        if new_visible {
            position_at_taskbar();
            let _ = ShowWindow(hwnd, SW_SHOWNOACTIVATE);
            render_layered();
        } else {
            let _ = ShowWindow(hwnd, SW_HIDE);
        }
    }
}

fn now_unix_secs() -> u64 {
    SystemTime::now()
        .duration_since(UNIX_EPOCH)
        .unwrap_or_default()
        .as_secs()
}

fn update_check_interval() -> Duration {
    Duration::from_secs(24 * 60 * 60)
}

fn auto_update_check_due(last_update_check_unix: Option<u64>) -> bool {
    let Some(last_update_check_unix) = last_update_check_unix else {
        return true;
    };

    now_unix_secs().saturating_sub(last_update_check_unix) >= update_check_interval().as_secs()
}

fn schedule_auto_update_check(hwnd: HWND) {
    let delay_ms = {
        let state = lock_state();
        let Some(s) = state.as_ref() else {
            return;
        };

        if auto_update_check_due(s.last_update_check_unix) {
            None
        } else {
            let elapsed = now_unix_secs().saturating_sub(s.last_update_check_unix.unwrap_or(0));
            let remaining_secs = update_check_interval().as_secs().saturating_sub(elapsed);
            Some((remaining_secs.saturating_mul(1000)).min(u32::MAX as u64) as u32)
        }
    };

    unsafe {
        let _ = KillTimer(hwnd, TIMER_UPDATE_CHECK);
        if let Some(delay_ms) = delay_ms {
            SetTimer(hwnd, TIMER_UPDATE_CHECK, delay_ms.max(1), None);
        }
    }
}

fn refresh_usage_texts(state: &mut AppState) {
    if !state.last_poll_ok {
        return;
    }

    let strings = state.language.strings();
    let Some((session_text, weekly_text)) = state.data.as_ref().map(|data| {
        (
            poller::format_line(&data.session, strings, state.show_decimals),
            poller::format_line(&data.weekly, strings, state.show_decimals),
        )
    }) else {
        return;
    };

    state.session_text = session_text;
    state.weekly_text = weekly_text;
}

fn set_window_title(hwnd: HWND, strings: Strings) {
    unsafe {
        let title = native_interop::wide_str(strings.window_title);
        let _ = SetWindowTextW(hwnd, PCWSTR::from_raw(title.as_ptr()));
    }
}

fn show_info_message(hwnd: HWND, title: &str, message: &str) {
    unsafe {
        let title_wide = native_interop::wide_str(title);
        let message_wide = native_interop::wide_str(message);
        let _ = MessageBoxW(
            hwnd,
            PCWSTR::from_raw(message_wide.as_ptr()),
            PCWSTR::from_raw(title_wide.as_ptr()),
            MB_OK | MB_ICONINFORMATION,
        );
    }
}

fn show_error_message(hwnd: HWND, title: &str, message: &str) {
    unsafe {
        let title_wide = native_interop::wide_str(title);
        let message_wide = native_interop::wide_str(message);
        let _ = MessageBoxW(
            hwnd,
            PCWSTR::from_raw(message_wide.as_ptr()),
            PCWSTR::from_raw(title_wide.as_ptr()),
            MB_OK | MB_ICONERROR,
        );
    }
}

fn show_update_prompt(hwnd: HWND, strings: Strings, release: &ReleaseDescriptor) -> bool {
    let message = strings
        .update_prompt_now
        .replace("{version}", &release.latest_version);

    unsafe {
        let title_wide = native_interop::wide_str(strings.update_available);
        let message_wide = native_interop::wide_str(&message);
        MessageBoxW(
            hwnd,
            PCWSTR::from_raw(message_wide.as_ptr()),
            PCWSTR::from_raw(title_wide.as_ptr()),
            MB_YESNO | MB_ICONQUESTION,
        ) == IDYES
    }
}

fn apply_language_to_state(state: &mut AppState, language_override: Option<LanguageId>) {
    state.language_override = language_override;
    state.language = localization::resolve_language(language_override);
    set_window_title(state.hwnd.to_hwnd(), state.language.strings());
    refresh_usage_texts(state);
}

fn update_language_change() -> bool {
    let mut state = lock_state();
    let Some(app_state) = state.as_mut() else {
        return false;
    };

    if app_state.language_override.is_some() {
        return false;
    }

    let new_language = localization::detect_system_language();
    if new_language == app_state.language {
        return false;
    }

    apply_language_to_state(app_state, None);
    true
}

fn version_action_label(
    strings: Strings,
    language: LanguageId,
    install_channel: InstallChannel,
    status: &UpdateStatus,
) -> String {
    let current = env!("CARGO_PKG_VERSION");
    match status {
        UpdateStatus::Idle => format!("v{current} - {}", strings.check_for_updates),
        UpdateStatus::Checking => format!("v{current} - {}", strings.checking_for_updates),
        UpdateStatus::Applying => format!("v{current} - {}", strings.applying_update),
        UpdateStatus::UpToDate => format!("v{current} - {}", strings.up_to_date_short),
        UpdateStatus::Available(release) => match install_channel {
            InstallChannel::Portable => {
                format!(
                    "v{current} - {} v{}",
                    strings.update_to, release.latest_version
                )
            }
            InstallChannel::Winget => format!(
                "v{current} - {} v{}",
                localization::update_via_winget(language),
                release.latest_version
            ),
        },
    }
}

fn begin_update_check(hwnd: HWND, interactive: bool) {
    let send_hwnd = SendHwnd::from_hwnd(hwnd);
    let (strings, install_channel) = {
        let mut state = lock_state();
        let Some(app_state) = state.as_mut() else {
            return;
        };

        if matches!(
            app_state.update_status,
            UpdateStatus::Checking | UpdateStatus::Applying
        ) {
            if interactive {
                show_info_message(
                    hwnd,
                    app_state.language.strings().updates,
                    app_state.language.strings().update_in_progress,
                );
            }
            return;
        }

        app_state.update_status = UpdateStatus::Checking;
        (app_state.language.strings(), app_state.install_channel)
    };

    std::thread::spawn(move || {
        let hwnd = send_hwnd.to_hwnd();
        let checked_at = now_unix_secs();
        match updater::check_for_updates() {
            Ok(UpdateCheckResult::UpToDate) => {
                {
                    let mut state = lock_state();
                    if let Some(s) = state.as_mut() {
                        s.update_status = UpdateStatus::UpToDate;
                        s.last_update_check_unix = Some(checked_at);
                    }
                }
                save_state_settings();
                if interactive {
                    show_info_message(hwnd, strings.updates, strings.up_to_date);
                }
                unsafe {
                    let _ = PostMessageW(hwnd, WM_APP_UPDATE_CHECK_COMPLETE, WPARAM(0), LPARAM(0));
                }
            }
            Ok(UpdateCheckResult::Available(release)) => {
                {
                    let mut state = lock_state();
                    if let Some(s) = state.as_mut() {
                        s.update_status = UpdateStatus::Available(release.clone());
                        s.last_update_check_unix = Some(checked_at);
                    }
                }
                save_state_settings();
                if interactive && show_update_prompt(hwnd, strings, &release) {
                    match install_channel {
                        InstallChannel::Portable => begin_update_apply(hwnd, release),
                        InstallChannel::Winget => begin_winget_update(hwnd),
                    }
                }
                unsafe {
                    let _ = PostMessageW(hwnd, WM_APP_UPDATE_CHECK_COMPLETE, WPARAM(0), LPARAM(0));
                }
            }
            Err(error) => {
                {
                    let mut state = lock_state();
                    if let Some(s) = state.as_mut() {
                        s.update_status = UpdateStatus::Idle;
                        s.last_update_check_unix = Some(checked_at);
                    }
                }
                save_state_settings();
                if interactive {
                    let message = format!("{}.\n\n{}", strings.update_failed, error);
                    show_error_message(hwnd, strings.updates, &message);
                }
                unsafe {
                    let _ = PostMessageW(hwnd, WM_APP_UPDATE_CHECK_COMPLETE, WPARAM(0), LPARAM(0));
                }
            }
        }
    });
}

fn begin_update_apply(hwnd: HWND, release: ReleaseDescriptor) {
    let send_hwnd = SendHwnd::from_hwnd(hwnd);
    let strings = {
        let mut state = lock_state();
        let Some(app_state) = state.as_mut() else {
            return;
        };

        if matches!(
            app_state.update_status,
            UpdateStatus::Checking | UpdateStatus::Applying
        ) {
            show_info_message(
                hwnd,
                app_state.language.strings().updates,
                app_state.language.strings().update_in_progress,
            );
            return;
        }

        app_state.update_status = UpdateStatus::Applying;
        app_state.language.strings()
    };

    std::thread::spawn(move || {
        let hwnd = send_hwnd.to_hwnd();
        match updater::begin_self_update(&release) {
            Ok(()) => unsafe {
                let _ = PostMessageW(hwnd, WM_CLOSE, WPARAM(0), LPARAM(0));
            },
            Err(error) => {
                {
                    let mut state = lock_state();
                    if let Some(s) = state.as_mut() {
                        s.update_status = UpdateStatus::Available(release);
                    }
                }
                let message = format!("{}.\n\n{}", strings.update_failed, error);
                show_error_message(hwnd, strings.updates, &message);
                unsafe {
                    let _ = PostMessageW(hwnd, WM_APP_UPDATE_CHECK_COMPLETE, WPARAM(0), LPARAM(0));
                }
            }
        }
    });
}

fn begin_winget_update(hwnd: HWND) {
    let strings = {
        let state = lock_state();
        state.as_ref().map(|s| s.language.strings())
    }
    .unwrap_or(LanguageId::English.strings());

    match updater::begin_winget_update() {
        Ok(()) => unsafe {
            let _ = PostMessageW(hwnd, WM_CLOSE, WPARAM(0), LPARAM(0));
        },
        Err(error) => {
            let message = format!("{}.\n\n{}", strings.update_failed, error);
            show_error_message(hwnd, strings.updates, &message);
        }
    }
}

const STARTUP_REGISTRY_PATH: &str = r"Software\Microsoft\Windows\CurrentVersion\Run";
const STARTUP_REGISTRY_KEY: &str = "ClaudeCodeUsageMonitor";

/// Returns true only if the startup registry value points to this executable.
fn is_startup_enabled() -> bool {
    unsafe {
        let path = native_interop::wide_str(STARTUP_REGISTRY_PATH);
        let key_name = native_interop::wide_str(STARTUP_REGISTRY_KEY);

        let mut hkey = HKEY::default();
        let result = RegOpenKeyExW(
            HKEY_CURRENT_USER,
            PCWSTR::from_raw(path.as_ptr()),
            0,
            KEY_READ,
            &mut hkey,
        );
        if result.is_err() {
            return false;
        }

        // Query the size of the value
        let mut data_size: u32 = 0;
        let result = RegQueryValueExW(
            hkey,
            PCWSTR::from_raw(key_name.as_ptr()),
            None,
            None,
            None,
            Some(&mut data_size),
        );
        if result.is_err() || data_size == 0 {
            let _ = RegCloseKey(hkey);
            return false;
        }

        // Read the value
        let mut buf = vec![0u8; data_size as usize];
        let result = RegQueryValueExW(
            hkey,
            PCWSTR::from_raw(key_name.as_ptr()),
            None,
            None,
            Some(buf.as_mut_ptr()),
            Some(&mut data_size),
        );
        let _ = RegCloseKey(hkey);
        if result.is_err() {
            return false;
        }

        // Convert the registry value (UTF-16) to a string
        let wide_slice =
            std::slice::from_raw_parts(buf.as_ptr() as *const u16, data_size as usize / 2);
        let reg_value = String::from_utf16_lossy(wide_slice)
            .trim_end_matches('\0')
            .to_string();

        // Get the current executable path
        let mut exe_buf = [0u16; 260];
        let len = GetModuleFileNameW(None, &mut exe_buf) as usize;
        if len == 0 {
            return false;
        }
        let current_exe = String::from_utf16_lossy(&exe_buf[..len]);

        // Case-insensitive comparison (Windows paths are case-insensitive)
        reg_value.eq_ignore_ascii_case(&current_exe)
    }
}

fn set_startup_enabled(enable: bool) {
    unsafe {
        let path = native_interop::wide_str(STARTUP_REGISTRY_PATH);

        let mut hkey = HKEY::default();
        let result = RegOpenKeyExW(
            HKEY_CURRENT_USER,
            PCWSTR::from_raw(path.as_ptr()),
            0,
            KEY_SET_VALUE,
            &mut hkey,
        );
        if result.is_err() {
            return;
        }

        let key_name = native_interop::wide_str(STARTUP_REGISTRY_KEY);

        if enable {
            let mut exe_buf = [0u16; 260];
            let len = GetModuleFileNameW(None, &mut exe_buf) as usize;
            if len > 0 {
                // Write the wide string including null terminator
                let byte_len = ((len + 1) * 2) as u32;
                let _ = RegSetValueExW(
                    hkey,
                    PCWSTR::from_raw(key_name.as_ptr()),
                    0,
                    REG_SZ,
                    Some(std::slice::from_raw_parts(
                        exe_buf.as_ptr() as *const u8,
                        byte_len as usize,
                    )),
                );
            }
        } else {
            let _ = RegDeleteValueW(hkey, PCWSTR::from_raw(key_name.as_ptr()));
        }

        let _ = RegCloseKey(hkey);
    }
}

// Dimensions matching the C# version
const SEGMENT_W: i32 = 10;
const SEGMENT_H: i32 = 13;
const SEGMENT_GAP: i32 = 1;
const SEGMENT_COUNT: i32 = 10;
const CORNER_RADIUS: i32 = 2;

const LEFT_DIVIDER_W: i32 = 3;
const DIVIDER_RIGHT_MARGIN: i32 = 10;
const LABEL_WIDTH: i32 = 18;
const LABEL_RIGHT_MARGIN: i32 = 10;
const BAR_RIGHT_MARGIN: i32 = 4;
const TEXT_WIDTH: i32 = 80;
const RIGHT_MARGIN: i32 = 1;
const WIDGET_HEIGHT: i32 = 46;

fn total_widget_width() -> i32 {
    sc(LEFT_DIVIDER_W)
        + sc(DIVIDER_RIGHT_MARGIN)
        + sc(LABEL_WIDTH)
        + sc(LABEL_RIGHT_MARGIN)
        + (sc(SEGMENT_W) + sc(SEGMENT_GAP)) * SEGMENT_COUNT
        - sc(SEGMENT_GAP)
        + sc(BAR_RIGHT_MARGIN)
        + sc(TEXT_WIDTH)
        + sc(RIGHT_MARGIN)
}

pub fn run() {
    // Enable Per-Monitor DPI Awareness V2 for crisp rendering at any scale factor
    unsafe {
        let _ = SetProcessDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2);
        CURRENT_DPI.store(GetDpiForSystem(), Ordering::Relaxed);
    }
    diagnose::log("window::run started");

    // Single-instance guard: silently exit if another instance is running
    let mutex_name = native_interop::wide_str("Global\\ClaudeCodeUsageMonitor");
    let _mutex = unsafe {
        let handle = CreateMutexW(None, false, PCWSTR::from_raw(mutex_name.as_ptr()));
        match handle {
            Ok(h) => {
                if GetLastError() == ERROR_ALREADY_EXISTS {
                    diagnose::log("startup aborted: another instance is already running");
                    return;
                }
                h
            }
            Err(error) => {
                diagnose::log_error("startup aborted: unable to create single-instance mutex", error);
                return;
            }
        }
    };

    let class_name = native_interop::wide_str("ClaudeCodeUsageMonitor");

    unsafe {
        let hinstance = GetModuleHandleW(PCWSTR::null()).unwrap();
        let (large_icon, small_icon) = load_embedded_app_icons();

        let wc = WNDCLASSEXW {
            cbSize: std::mem::size_of::<WNDCLASSEXW>() as u32,
            style: CS_HREDRAW | CS_VREDRAW,
            lpfnWndProc: Some(wnd_proc),
            hInstance: HINSTANCE(hinstance.0),
            hIcon: large_icon,
            hIconSm: small_icon,
            hCursor: LoadCursorW(HINSTANCE::default(), IDC_ARROW).unwrap_or_default(),
            hbrBackground: HBRUSH(std::ptr::null_mut()),
            lpszClassName: PCWSTR::from_raw(class_name.as_ptr()),
            ..Default::default()
        };

        let atom = RegisterClassExW(&wc);
        if atom == 0 {
            diagnose::log("RegisterClassExW returned 0");
        }

        let settings = load_settings();
        let language_override = settings.language.as_deref().and_then(LanguageId::from_code);
        let language = localization::resolve_language(language_override);
        let install_channel = updater::current_install_channel();

        // Create as layered popup (will be reparented into taskbar)
        let title = native_interop::wide_str(language.strings().window_title);
        let hwnd = CreateWindowExW(
            WS_EX_TOOLWINDOW | WS_EX_LAYERED | WS_EX_NOACTIVATE,
            PCWSTR::from_raw(class_name.as_ptr()),
            PCWSTR::from_raw(title.as_ptr()),
            WS_POPUP,
            0,
            0,
            total_widget_width(),
            sc(WIDGET_HEIGHT),
            HWND::default(),
            HMENU::default(),
            hinstance,
            None,
        )
        .unwrap();

        if !large_icon.is_invalid() {
            let _ = SendMessageW(
                hwnd,
                WM_SETICON,
                WPARAM(ICON_BIG as usize),
                LPARAM(large_icon.0 as isize),
            );
        }
        if !small_icon.is_invalid() {
            let _ = SendMessageW(
                hwnd,
                WM_SETICON,
                WPARAM(ICON_SMALL as usize),
                LPARAM(small_icon.0 as isize),
            );
        }

        diagnose::log(format!("main window created hwnd={:?}", hwnd));

        let is_dark = theme::is_dark_mode();
        let mut embedded = false;

        {
            let mut state = lock_state();
            *state = Some(AppState {
                hwnd: SendHwnd::from_hwnd(hwnd),
                taskbar_hwnd: None,
                tray_notify_hwnd: None,
                win_event_hook: None,
                is_dark,
                embedded: false,
                language_override,
                language,
                install_channel,
                session_percent: 0.0,
                session_text: "--".to_string(),
                weekly_percent: 0.0,
                weekly_text: "--".to_string(),
                data: None,
                poll_interval_ms: settings.poll_interval_ms,
                retry_count: 0,
                last_poll_ok: false,
                update_status: UpdateStatus::Idle,
                last_update_check_unix: settings.last_update_check_unix,
                tray_offset: settings.tray_offset,
                dragging: false,
                drag_start_mouse_x: 0,
                drag_start_offset: 0,
                show_decimals: settings.show_decimals,
                widget_visible: settings.widget_visible,
            });
        }

        // Try to embed in taskbar
        if let Some(taskbar_hwnd) = native_interop::find_taskbar() {
            diagnose::log(format!("taskbar found hwnd={:?}", taskbar_hwnd));
            native_interop::embed_in_taskbar(hwnd, taskbar_hwnd);
            embedded = true;

            let mut state = lock_state();
            let s = state.as_mut().unwrap();
            s.taskbar_hwnd = Some(taskbar_hwnd);
            s.embedded = true;

            let tray_notify = native_interop::find_child_window(taskbar_hwnd, "TrayNotifyWnd");
            s.tray_notify_hwnd = tray_notify;
            if tray_notify.is_some() {
                diagnose::log("TrayNotifyWnd found");
            } else {
                diagnose::log("TrayNotifyWnd not found");
            }

            if let Some(tray_hwnd) = tray_notify {
                let thread_id = native_interop::get_window_thread_id(tray_hwnd);
                let hook = native_interop::set_tray_event_hook(thread_id, on_tray_location_changed);
                s.win_event_hook = hook;
                if hook.is_some() {
                    diagnose::log("tray event hook installed");
                } else {
                    diagnose::log("tray event hook could not be installed");
                }
            }
        } else {
            diagnose::log("taskbar not found; using fallback popup window");
        }

        // If not embedded, fall back to topmost popup with SetLayeredWindowAttributes
        if !embedded {
            let _ = SetLayeredWindowAttributes(hwnd, COLORREF(0), 255, LWA_ALPHA);
            let _ = SetWindowPos(
                hwnd,
                HWND_TOPMOST,
                0,
                0,
                0,
                0,
                SWP_NOMOVE | SWP_NOSIZE | SWP_NOACTIVATE,
            );
        }

        // Register system tray icon
        let (tray_pct, tray_tooltip) = tray_icon_data_from_state();
        tray_icon::add(hwnd, tray_pct, &tray_tooltip);

        // Position and show (only if widget_visible preference is true)
        position_at_taskbar();
        if settings.widget_visible {
            let _ = ShowWindow(hwnd, SW_SHOWNOACTIVATE);
        }
        diagnose::log("window shown");

        // Initial render via UpdateLayeredWindow (for embedded) or InvalidateRect (fallback)
        render_layered();

        // Poll timer: 15 minutes
        let initial_poll_ms = {
            let state = lock_state();
            state
                .as_ref()
                .map(|s| s.poll_interval_ms)
                .unwrap_or(POLL_15_MIN)
        };
        SetTimer(hwnd, TIMER_POLL, initial_poll_ms, None);

        // Initial poll
        let send_hwnd = SendHwnd::from_hwnd(hwnd);
        std::thread::spawn(move || {
            diagnose::log("initial poll thread started");
            do_poll(send_hwnd);
        });

        schedule_auto_update_check(hwnd);
        let should_check_updates = {
            let state = lock_state();
            state
                .as_ref()
                .map(|s| auto_update_check_due(s.last_update_check_unix))
                .unwrap_or(false)
        };
        if should_check_updates {
            begin_update_check(hwnd, false);
        }

        // Initial theme check
        check_theme_change();

        // Message loop
        let mut msg = MSG::default();
        while GetMessageW(&mut msg, HWND::default(), 0, 0).as_bool() {
            let _ = TranslateMessage(&msg);
            DispatchMessageW(&msg);
        }
    }
}

/// Render widget content and push to the layered window via UpdateLayeredWindow.
/// Renders fully opaque with the actual taskbar background colour so that
/// ClearType sub-pixel font rendering can be used for crisp, OS-native text.
fn render_layered() {
    refresh_dpi();
    let (hwnd_val, is_dark, embedded, strings, session_pct, session_text, weekly_pct, weekly_text) = {
        let state = lock_state();
        match state.as_ref() {
            Some(s) => (
                s.hwnd,
                s.is_dark,
                s.embedded,
                s.language.strings(),
                s.session_percent,
                s.session_text.clone(),
                s.weekly_percent,
                s.weekly_text.clone(),
            ),
            None => return,
        }
    };

    let hwnd = hwnd_val.to_hwnd();

    // For non-embedded fallback, just invalidate and let WM_PAINT handle it
    if !embedded {
        unsafe {
            let _ = InvalidateRect(hwnd, None, false);
        }
        return;
    }

    let width = total_widget_width();
    let height = sc(WIDGET_HEIGHT);

    let accent = Color::from_hex("#D97757");
    let track = if is_dark {
        Color::from_hex("#444444")
    } else {
        Color::from_hex("#AAAAAA")
    };
    let text_color = if is_dark {
        Color::from_hex("#888888")
    } else {
        Color::from_hex("#404040")
    };
    let bg_color = if is_dark {
        Color::from_hex("#1C1C1C")
    } else {
        Color::from_hex("#F3F3F3")
    };

    unsafe {
        let screen_dc = GetDC(hwnd);

        let bmi = BITMAPINFO {
            bmiHeader: BITMAPINFOHEADER {
                biSize: std::mem::size_of::<BITMAPINFOHEADER>() as u32,
                biWidth: width,
                biHeight: -height, // top-down
                biPlanes: 1,
                biBitCount: 32,
                biCompression: 0, // BI_RGB
                ..Default::default()
            },
            ..Default::default()
        };

        let mut bits: *mut std::ffi::c_void = std::ptr::null_mut();
        let mem_dc = CreateCompatibleDC(screen_dc);
        let dib =
            CreateDIBSection(mem_dc, &bmi, DIB_RGB_COLORS, &mut bits, None, 0).unwrap_or_default();

        if dib.is_invalid() || bits.is_null() {
            let _ = DeleteDC(mem_dc);
            ReleaseDC(hwnd, screen_dc);
            return;
        }

        let old_bmp = SelectObject(mem_dc, dib);
        let pixel_count = (width * height) as usize;

        // Render once with the actual taskbar background colour.
        // Using an opaque background lets us use CLEARTYPE_QUALITY for
        // sub-pixel font rendering that matches the rest of the OS.
        paint_content(
            mem_dc,
            width,
            height,
            is_dark,
            &bg_color,
            &text_color,
            &accent,
            &track,
            strings,
            session_pct,
            &session_text,
            weekly_pct,
            &weekly_text,
        );

        // Background pixels → alpha 1 (nearly invisible but still hittable for right-click).
        // Content pixels → fully opaque (preserves ClearType sub-pixel rendering).
        let bg_bgr = bg_color.to_colorref();
        let pixel_data = std::slice::from_raw_parts_mut(bits as *mut u32, pixel_count);
        for px in pixel_data.iter_mut() {
            let rgb = *px & 0x00FFFFFF;
            if rgb == bg_bgr {
                *px = 0x01000000;
            } else {
                *px = rgb | 0xFF000000;
            }
        }

        // Push to window via UpdateLayeredWindow
        let pt_src = POINT { x: 0, y: 0 };
        let sz = SIZE {
            cx: width,
            cy: height,
        };
        let blend = BLENDFUNCTION {
            BlendOp: 0, // AC_SRC_OVER
            BlendFlags: 0,
            SourceConstantAlpha: 255,
            AlphaFormat: 1, // AC_SRC_ALPHA
        };

        let _ = UpdateLayeredWindow(
            hwnd,
            screen_dc,
            None,
            Some(&sz),
            mem_dc,
            Some(&pt_src),
            COLORREF(0),
            Some(&blend),
            ULW_ALPHA,
        );

        // Cleanup
        SelectObject(mem_dc, old_bmp);
        let _ = DeleteObject(dib);
        let _ = DeleteDC(mem_dc);
        ReleaseDC(hwnd, screen_dc);
    }
}

/// Paint all widget content onto a DC with a given background color.
fn paint_content(
    hdc: HDC,
    width: i32,
    height: i32,
    is_dark: bool,
    bg: &Color,
    text_color: &Color,
    accent: &Color,
    track: &Color,
    strings: Strings,
    session_pct: f64,
    session_text: &str,
    weekly_pct: f64,
    weekly_text: &str,
) {
    unsafe {
        let client_rect = RECT {
            left: 0,
            top: 0,
            right: width,
            bottom: height,
        };

        let bg_brush = CreateSolidBrush(COLORREF(bg.to_colorref()));
        FillRect(hdc, &client_rect, bg_brush);
        let _ = DeleteObject(bg_brush);

        // Left divider
        let divider_h = sc(25);
        let divider_top = (height - divider_h) / 2;
        let divider_bottom = divider_top + divider_h;

        let (div_left, div_right) = if is_dark {
            ((80, 80, 80), (40, 40, 40))
        } else {
            ((160, 160, 160), (230, 230, 230))
        };

        let left_brush = CreateSolidBrush(COLORREF(native_interop::colorref(
            div_left.0, div_left.1, div_left.2,
        )));
        let left_rect = RECT {
            left: 0,
            top: divider_top,
            right: sc(2),
            bottom: divider_bottom,
        };
        FillRect(hdc, &left_rect, left_brush);
        let _ = DeleteObject(left_brush);

        let right_brush = CreateSolidBrush(COLORREF(native_interop::colorref(
            div_right.0,
            div_right.1,
            div_right.2,
        )));
        let right_rect = RECT {
            left: sc(2),
            top: divider_top,
            right: sc(3),
            bottom: divider_bottom,
        };
        FillRect(hdc, &right_rect, right_brush);
        let _ = DeleteObject(right_brush);

        let content_x = sc(LEFT_DIVIDER_W) + sc(DIVIDER_RIGHT_MARGIN);
        let row2_y = height - sc(5) - sc(SEGMENT_H);
        let row1_y = row2_y - sc(10) - sc(SEGMENT_H);

        let _ = SetBkMode(hdc, TRANSPARENT);
        let _ = SetTextColor(hdc, COLORREF(text_color.to_colorref()));

        let font_name = native_interop::wide_str("Segoe UI");
        let font = CreateFontW(
            sc(-12),
            0,
            0,
            0,
            FW_MEDIUM.0 as i32,
            0,
            0,
            0,
            DEFAULT_CHARSET.0 as u32,
            OUT_TT_PRECIS.0 as u32,
            CLIP_DEFAULT_PRECIS.0 as u32,
            CLEARTYPE_QUALITY.0 as u32,
            (DEFAULT_PITCH.0 | FF_DONTCARE.0) as u32,
            PCWSTR::from_raw(font_name.as_ptr()),
        );
        let old_font = SelectObject(hdc, font);

        draw_row(
            hdc,
            content_x,
            row1_y,
            strings.session_window,
            session_pct,
            session_text,
            accent,
            track,
        );
        draw_row(
            hdc,
            content_x,
            row2_y,
            strings.weekly_window,
            weekly_pct,
            weekly_text,
            accent,
            track,
        );

        SelectObject(hdc, old_font);
        let _ = DeleteObject(font);
    }
}

fn do_poll(send_hwnd: SendHwnd) {
    let hwnd = send_hwnd.to_hwnd();
    match poller::poll() {
        Ok(data) => {
            let mut state = lock_state();
            if let Some(s) = state.as_mut() {
                s.session_percent = data.session.percentage;
                s.weekly_percent = data.weekly.percentage;
                // Stop fast-poll if reset data is now fresh
                if !poller::is_past_reset(&data) {
                    unsafe {
                        let _ = KillTimer(hwnd, TIMER_RESET_POLL);
                    }
                }

                s.data = Some(data);
                s.last_poll_ok = true;
                refresh_usage_texts(s);

                // Recovered from errors — restore normal poll interval
                if s.retry_count > 0 {
                    s.retry_count = 0;
                    let interval = s.poll_interval_ms;
                    unsafe {
                        SetTimer(hwnd, TIMER_POLL, interval, None);
                    }
                }
            }

            unsafe {
                let _ = PostMessageW(hwnd, WM_APP_USAGE_UPDATED, WPARAM(0), LPARAM(0));
            }
        }
        Err(_e) => {
            // Show refresh indicator — retry will recover silently
            let mut state = lock_state();
            if let Some(s) = state.as_mut() {
                s.session_text = "...".to_string();
                s.weekly_text = "...".to_string();
                s.last_poll_ok = false;

                // Exponential backoff retry: 30s, 60s, 120s, ... up to poll_interval
                s.retry_count = s.retry_count.saturating_add(1);
                let backoff = RETRY_BASE_MS
                    .saturating_mul(1u32.checked_shl(s.retry_count - 1).unwrap_or(u32::MAX));
                let retry_ms = backoff.min(s.poll_interval_ms);

                unsafe {
                    // Kill the 5-second reset poll so it doesn't bypass backoff
                    let _ = KillTimer(hwnd, TIMER_RESET_POLL);
                    SetTimer(hwnd, TIMER_POLL, retry_ms, None);
                }
            }

            unsafe {
                let _ = PostMessageW(hwnd, WM_APP_USAGE_UPDATED, WPARAM(0), LPARAM(0));
            }
        }
    }
}

fn schedule_countdown_timer() {
    let state = lock_state();
    let s = match state.as_ref() {
        Some(s) => s,
        None => return,
    };

    let data = match &s.data {
        Some(d) => d,
        None => return,
    };

    let hwnd = s.hwnd.to_hwnd();

    // If a reset time has passed, poll every 5s to pick up fresh data
    if poller::is_past_reset(data) {
        unsafe {
            SetTimer(hwnd, TIMER_RESET_POLL, 5_000, None);
        }
    }

    let session_delay = poller::time_until_display_change(data.session.resets_at);
    let weekly_delay = poller::time_until_display_change(data.weekly.resets_at);

    let min_delay = match (session_delay, weekly_delay) {
        (Some(a), Some(b)) => Some(a.min(b)),
        (Some(a), None) => Some(a),
        (None, Some(b)) => Some(b),
        (None, None) => None,
    };

    let ms = min_delay
        .unwrap_or(Duration::from_secs(60))
        .as_millis()
        .max(1000) as u32;

    unsafe {
        SetTimer(hwnd, TIMER_COUNTDOWN, ms, None);
    }
}

fn check_theme_change() {
    let new_dark = theme::is_dark_mode();
    let changed = {
        let mut state = lock_state();
        if let Some(s) = state.as_mut() {
            if s.is_dark != new_dark {
                s.is_dark = new_dark;
                true
            } else {
                false
            }
        } else {
            false
        }
    };
    if changed {
        render_layered();
    }
}

fn check_language_change() {
    if update_language_change() {
        render_layered();
    }
}

fn update_display() {
    let mut state = lock_state();
    let s = match state.as_mut() {
        Some(s) => s,
        None => return,
    };

    // Don't overwrite error text with stale cached data
    if !s.last_poll_ok {
        return;
    }

    refresh_usage_texts(s);
}

fn position_at_taskbar() {
    refresh_dpi();
    let state = lock_state();
    let s = match state.as_ref() {
        Some(s) => s,
        None => return,
    };

    // Don't fight the user's drag
    if s.dragging {
        return;
    }

    let hwnd = s.hwnd.to_hwnd();
    let embedded = s.embedded;
    let tray_offset = s.tray_offset;

    let taskbar_hwnd = match s.taskbar_hwnd {
        Some(h) => h,
        None => {
            diagnose::log("position_at_taskbar skipped: no taskbar handle");
            return;
        }
    };

    let taskbar_rect = match native_interop::get_taskbar_rect(taskbar_hwnd) {
        Some(r) => r,
        None => {
            diagnose::log("position_at_taskbar skipped: unable to query taskbar rect");
            return;
        }
    };

    let taskbar_height = taskbar_rect.bottom - taskbar_rect.top;
    let mut tray_left = taskbar_rect.right;
    let anchor_top = taskbar_rect.top;
    let anchor_height = taskbar_height;

    if let Some(tray_hwnd) = native_interop::find_child_window(taskbar_hwnd, "TrayNotifyWnd") {
        if let Some(tray_rect) = native_interop::get_window_rect_safe(tray_hwnd) {
            tray_left = tray_rect.left;
        }
    }

    let widget_width = total_widget_width();

    let widget_height = sc(WIDGET_HEIGHT);
    let y = compute_anchor_y(anchor_top, anchor_height, widget_height);
    if embedded {
        // Child window: coordinates relative to parent (taskbar)
        let x = tray_left - taskbar_rect.left - widget_width - tray_offset;
        native_interop::move_window(hwnd, x, y - taskbar_rect.top, widget_width, widget_height);
        diagnose::log(format!(
            "positioned embedded widget at x={x} y={} w={widget_width} h={widget_height}",
            y - taskbar_rect.top
        ));
    } else {
        // Topmost popup: screen coordinates
        let x = tray_left - widget_width - tray_offset;
        native_interop::move_window(hwnd, x, y, widget_width, widget_height);
        diagnose::log(format!(
            "positioned fallback widget at x={x} y={y} w={widget_width} h={widget_height}"
        ));
    }
}

fn compute_anchor_y(anchor_top: i32, anchor_height: i32, widget_height: i32) -> i32 {
    let anchor_bottom = anchor_top + anchor_height;
    (anchor_bottom - widget_height).max(anchor_top)
}

/// WinEvent callback for tray icon location changes
unsafe extern "system" fn on_tray_location_changed(
    _hook: HWINEVENTHOOK,
    _event: u32,
    hwnd: HWND,
    _id_object: i32,
    _id_child: i32,
    _thread: u32,
    _time: u32,
) {
    static LAST_REPOSITION: Mutex<Option<std::time::Instant>> = Mutex::new(None);

    let is_tray = {
        let state = lock_state();
        state
            .as_ref()
            .and_then(|s| s.tray_notify_hwnd)
            .map(|h| h == hwnd)
            .unwrap_or(false)
    };

    if is_tray {
        let should_reposition = {
            let mut last = LAST_REPOSITION.lock().unwrap_or_else(|e| e.into_inner());
            let now = std::time::Instant::now();
            if last
                .map(|t| now.duration_since(t).as_millis() > 500)
                .unwrap_or(true)
            {
                *last = Some(now);
                true
            } else {
                false
            }
        };
        if should_reposition {
            position_at_taskbar();
            render_layered();
        }
    }
}

/// Main window procedure
unsafe extern "system" fn wnd_proc(
    hwnd: HWND,
    msg: u32,
    wparam: WPARAM,
    lparam: LPARAM,
) -> LRESULT {
    match msg {
        WM_PAINT => {
            // For non-embedded fallback, paint normally
            let embedded = {
                let state = lock_state();
                state.as_ref().map(|s| s.embedded).unwrap_or(false)
            };
            if embedded {
                // Layered windows don't use WM_PAINT; just validate the region
                let mut ps = PAINTSTRUCT::default();
                let _ = BeginPaint(hwnd, &mut ps);
                let _ = EndPaint(hwnd, &ps);
            } else {
                let mut ps = PAINTSTRUCT::default();
                let hdc = BeginPaint(hwnd, &mut ps);
                paint(hdc, hwnd);
                let _ = EndPaint(hwnd, &ps);
            }
            LRESULT(0)
        }
        WM_ERASEBKGND => LRESULT(1),
        WM_DISPLAYCHANGE | WM_DPICHANGED_MSG | WM_SETTINGCHANGE => {
            if msg == WM_DPICHANGED_MSG {
                let new_dpi = (wparam.0 & 0xFFFF) as u32;
                CURRENT_DPI.store(new_dpi, Ordering::Relaxed);
            }
            if msg == WM_SETTINGCHANGE {
                check_theme_change();
                check_language_change();
            }
            refresh_dpi();
            position_at_taskbar();
            render_layered();
            LRESULT(0)
        }
        WM_TIMER => {
            let timer_id = wparam.0;
            match timer_id {
                TIMER_POLL => {
                    let sh = SendHwnd::from_hwnd(hwnd);
                    std::thread::spawn(move || {
                        do_poll(sh);
                    });
                }
                TIMER_COUNTDOWN => {
                    update_display();
                    render_layered();
                    schedule_countdown_timer();
                }
                TIMER_RESET_POLL => {
                    let sh = SendHwnd::from_hwnd(hwnd);
                    std::thread::spawn(move || {
                        do_poll(sh);
                    });
                }
                TIMER_UPDATE_CHECK => {
                    begin_update_check(hwnd, false);
                }
                _ => {}
            }
            LRESULT(0)
        }
        WM_APP_USAGE_UPDATED => {
            check_theme_change();
            check_language_change();
            render_layered();
            schedule_countdown_timer();
            let (pct, tooltip) = tray_icon_data_from_state();
            tray_icon::update(hwnd, pct, &tooltip);
            LRESULT(0)
        }
        WM_APP_UPDATE_CHECK_COMPLETE => {
            schedule_auto_update_check(hwnd);
            LRESULT(0)
        }
        WM_SETCURSOR => {
            let is_dragging = {
                let state = lock_state();
                state.as_ref().map(|s| s.dragging).unwrap_or(false)
            };
            // Always show resize cursor while dragging or when hovering divider zone
            let hit_test = (lparam.0 & 0xFFFF) as u16;
            if is_dragging {
                let cursor = LoadCursorW(HINSTANCE::default(), IDC_SIZEWE).unwrap_or_default();
                SetCursor(cursor);
                return LRESULT(1);
            }
            if hit_test == 1 {
                // HTCLIENT
                let mut pt = POINT::default();
                let _ = GetCursorPos(&mut pt);
                let _ = ScreenToClient(hwnd, &mut pt);
                if pt.x < sc(DIVIDER_HIT_ZONE) {
                    let cursor = LoadCursorW(HINSTANCE::default(), IDC_SIZEWE).unwrap_or_default();
                    SetCursor(cursor);
                    return LRESULT(1);
                }
            }
            DefWindowProcW(hwnd, msg, wparam, lparam)
        }
        WM_LBUTTONDOWN => {
            let client_x = (lparam.0 & 0xFFFF) as i16 as i32;
            if client_x < sc(DIVIDER_HIT_ZONE) {
                let mut pt = POINT::default();
                let _ = GetCursorPos(&mut pt);
                let mut state = lock_state();
                if let Some(s) = state.as_mut() {
                    s.dragging = true;
                    s.drag_start_mouse_x = pt.x;
                    s.drag_start_offset = s.tray_offset;
                }
                SetCapture(hwnd);
            }
            LRESULT(0)
        }
        WM_MOUSEMOVE => {
            let is_dragging = {
                let state = lock_state();
                state.as_ref().map(|s| s.dragging).unwrap_or(false)
            };
            if is_dragging {
                let mut pt = POINT::default();
                let _ = GetCursorPos(&mut pt);

                let mut state = lock_state();
                let s = match state.as_mut() {
                    Some(s) => s,
                    None => return LRESULT(0),
                };

                // Moving mouse left = positive delta = larger offset (further left)
                let delta = s.drag_start_mouse_x - pt.x;
                let mut new_offset = s.drag_start_offset + delta;

                // Clamp: offset >= 0 (can't go right of default)
                if new_offset < 0 {
                    new_offset = 0;
                }

                // Clamp: don't go past left edge of taskbar
                if let Some(taskbar_hwnd) = s.taskbar_hwnd {
                    if let Some(taskbar_rect) = native_interop::get_taskbar_rect(taskbar_hwnd) {
                        let mut tray_left = taskbar_rect.right;
                        if let Some(tray_hwnd) =
                            native_interop::find_child_window(taskbar_hwnd, "TrayNotifyWnd")
                        {
                            if let Some(tray_rect) = native_interop::get_window_rect_safe(tray_hwnd)
                            {
                                tray_left = tray_rect.left;
                            }
                        }
                        let widget_width = total_widget_width();
                        let max_offset = if s.embedded {
                            tray_left - taskbar_rect.left - widget_width
                        } else {
                            tray_left - taskbar_rect.left - widget_width
                        };
                        if new_offset > max_offset {
                            new_offset = max_offset;
                        }
                    }
                }

                s.tray_offset = new_offset;

                // Move window directly
                let hwnd_val = s.hwnd.to_hwnd();
                if let Some(taskbar_hwnd) = s.taskbar_hwnd {
                    if let Some(taskbar_rect) = native_interop::get_taskbar_rect(taskbar_hwnd) {
                        let taskbar_height = taskbar_rect.bottom - taskbar_rect.top;
                        let mut tray_left = taskbar_rect.right;
                        let anchor_top = taskbar_rect.top;
                        let anchor_height = taskbar_height;
                        if let Some(tray_hwnd) =
                            native_interop::find_child_window(taskbar_hwnd, "TrayNotifyWnd")
                        {
                            if let Some(tray_rect) = native_interop::get_window_rect_safe(tray_hwnd)
                            {
                                tray_left = tray_rect.left;
                            }
                        }
                        let widget_width = total_widget_width();
                        let widget_height = sc(WIDGET_HEIGHT);
                        let y = compute_anchor_y(anchor_top, anchor_height, widget_height);
                        if s.embedded {
                            let x = tray_left - taskbar_rect.left - widget_width - new_offset;
                            native_interop::move_window(
                                hwnd_val,
                                x,
                                y - taskbar_rect.top,
                                widget_width,
                                widget_height,
                            );
                        } else {
                            let x = tray_left - widget_width - new_offset;
                            native_interop::move_window(
                                hwnd_val,
                                x,
                                y,
                                widget_width,
                                widget_height,
                            );
                        }
                    }
                }
            }
            LRESULT(0)
        }
        WM_LBUTTONUP => {
            let was_dragging = {
                let mut state = lock_state();
                if let Some(s) = state.as_mut() {
                    if s.dragging {
                        s.dragging = false;
                        let offset = s.tray_offset;
                        Some(offset)
                    } else {
                        None
                    }
                } else {
                    None
                }
            };
            if was_dragging.is_some() {
                let _ = ReleaseCapture();
                save_state_settings();
            }
            LRESULT(0)
        }
        WM_RBUTTONUP => {
            show_context_menu(hwnd);
            LRESULT(0)
        }
        WM_COMMAND => {
            let id = wparam.0 as u16;
            match id {
                1 => {
                    {
                        let mut state = lock_state();
                        if let Some(s) = state.as_mut() {
                            s.session_text = "...".to_string();
                            s.weekly_text = "...".to_string();
                        }
                    }
                    render_layered();
                    let sh = SendHwnd::from_hwnd(hwnd);
                    std::thread::spawn(move || {
                        do_poll(sh);
                    });
                }
                IDM_VERSION_ACTION => {
                    let (install_channel, release) = {
                        let state = lock_state();
                        match state.as_ref() {
                            Some(s) => (
                                s.install_channel,
                                match &s.update_status {
                                    UpdateStatus::Available(release) => Some(release.clone()),
                                    _ => None,
                                },
                            ),
                            None => (InstallChannel::Portable, None),
                        }
                    };

                    match install_channel {
                        InstallChannel::Winget => {
                            if release.is_some() {
                                begin_winget_update(hwnd);
                            } else {
                                begin_update_check(hwnd, true);
                            }
                        }
                        InstallChannel::Portable => {
                            if let Some(release) = release {
                                begin_update_apply(hwnd, release);
                            } else {
                                begin_update_check(hwnd, true);
                            }
                        }
                    }
                }
                2 => {
                    let hook = {
                        let state = lock_state();
                        state.as_ref().and_then(|s| s.win_event_hook)
                    };
                    if let Some(h) = hook {
                        native_interop::unhook_win_event(h);
                    }
                    PostQuitMessage(0);
                }
                IDM_RESET_POSITION => {
                    {
                        let mut state = lock_state();
                        if let Some(s) = state.as_mut() {
                            s.tray_offset = 0;
                        }
                    }
                    save_state_settings();
                    position_at_taskbar();
                }
                IDM_START_WITH_WINDOWS => {
                    set_startup_enabled(!is_startup_enabled());
                }
                IDM_SHOW_DECIMALS => {
                    {
                        let mut state = lock_state();
                        if let Some(s) = state.as_mut() {
                            s.show_decimals = !s.show_decimals;
                        }
                    }
                    save_state_settings();
                    render_layered();
                }
                IDM_FREQ_1MIN | IDM_FREQ_5MIN | IDM_FREQ_15MIN | IDM_FREQ_1HOUR => {
                    let new_interval = match id {
                        IDM_FREQ_1MIN => POLL_1_MIN,
                        IDM_FREQ_5MIN => POLL_5_MIN,
                        IDM_FREQ_15MIN => POLL_15_MIN,
                        IDM_FREQ_1HOUR => POLL_1_HOUR,
                        _ => POLL_15_MIN,
                    };
                    {
                        let mut state = lock_state();
                        if let Some(s) = state.as_mut() {
                            s.poll_interval_ms = new_interval;
                        }
                    }
                    save_state_settings();
                    // Reset the poll timer with the new interval
                    SetTimer(hwnd, TIMER_POLL, new_interval, None);
                }
                IDM_LANG_SYSTEM | IDM_LANG_ENGLISH | IDM_LANG_SPANISH | IDM_LANG_FRENCH
                | IDM_LANG_GERMAN | IDM_LANG_JAPANESE => {
                    let language_override = match id {
                        IDM_LANG_SYSTEM => None,
                        IDM_LANG_ENGLISH => Some(LanguageId::English),
                        IDM_LANG_SPANISH => Some(LanguageId::Spanish),
                        IDM_LANG_FRENCH => Some(LanguageId::French),
                        IDM_LANG_GERMAN => Some(LanguageId::German),
                        IDM_LANG_JAPANESE => Some(LanguageId::Japanese),
                        _ => None,
                    };
                    {
                        let mut state = lock_state();
                        if let Some(s) = state.as_mut() {
                            apply_language_to_state(s, language_override);
                        }
                    }
                    save_state_settings();
                    render_layered();
                }
                id if id == tray_icon::IDM_TOGGLE_WIDGET => {
                    toggle_widget_visibility(hwnd);
                }
                _ => {}
            }
            LRESULT(0)
        }
        _ if msg == WM_APP_TRAY => {
            match tray_icon::handle_message(lparam) {
                tray_icon::TrayAction::ToggleWidget => {
                    toggle_widget_visibility(hwnd);
                }
                tray_icon::TrayAction::ShowContextMenu => {
                    show_context_menu(hwnd);
                }
                tray_icon::TrayAction::None => {}
            }
            LRESULT(0)
        }
        WM_DESTROY => {
            let hook = {
                let state = lock_state();
                state.as_ref().and_then(|s| s.win_event_hook)
            };
            if let Some(h) = hook {
                native_interop::unhook_win_event(h);
            }
            tray_icon::remove(hwnd);
            PostQuitMessage(0);
            LRESULT(0)
        }
        _ => DefWindowProcW(hwnd, msg, wparam, lparam),
    }
}

fn show_context_menu(hwnd: HWND) {
    unsafe {
        let (
            current_interval,
            strings,
            language,
            language_override,
            install_channel,
            update_status,
            widget_visible,
        ) = {
            let state = lock_state();
            match state.as_ref() {
                Some(s) => (
                    s.poll_interval_ms,
                    s.language.strings(),
                    s.language,
                    s.language_override,
                    s.install_channel,
                    s.update_status.clone(),
                    s.widget_visible,
                ),
                None => (
                    POLL_15_MIN,
                    LanguageId::English.strings(),
                    LanguageId::English,
                    None,
                    InstallChannel::Portable,
                    UpdateStatus::Idle,
                    true,
                ),
            }
        };

        let menu = CreatePopupMenu().unwrap();

        let refresh_str = native_interop::wide_str(strings.refresh);
        let _ = AppendMenuW(
            menu,
            MENU_ITEM_FLAGS(0),
            1,
            PCWSTR::from_raw(refresh_str.as_ptr()),
        );

        // Update Frequency submenu
        let freq_menu = CreatePopupMenu().unwrap();
        let freq_items: [(u16, u32, &str); 4] = [
            (IDM_FREQ_1MIN, POLL_1_MIN, strings.one_minute),
            (IDM_FREQ_5MIN, POLL_5_MIN, strings.five_minutes),
            (IDM_FREQ_15MIN, POLL_15_MIN, strings.fifteen_minutes),
            (IDM_FREQ_1HOUR, POLL_1_HOUR, strings.one_hour),
        ];
        for (id, interval, label) in freq_items {
            let label_str = native_interop::wide_str(label);
            let flags = if interval == current_interval {
                MF_CHECKED
            } else {
                MENU_ITEM_FLAGS(0)
            };
            let _ = AppendMenuW(
                freq_menu,
                flags,
                id as usize,
                PCWSTR::from_raw(label_str.as_ptr()),
            );
        }

        let freq_label = native_interop::wide_str(strings.update_frequency);
        let _ = AppendMenuW(
            menu,
            MF_POPUP,
            freq_menu.0 as usize,
            PCWSTR::from_raw(freq_label.as_ptr()),
        );

        // Settings submenu
        let settings_menu = CreatePopupMenu().unwrap();

        let startup_str = native_interop::wide_str(strings.start_with_windows);
        let startup_flags = if is_startup_enabled() {
            MF_CHECKED
        } else {
            MENU_ITEM_FLAGS(0)
        };
        let _ = AppendMenuW(
            settings_menu,
            startup_flags,
            IDM_START_WITH_WINDOWS as usize,
            PCWSTR::from_raw(startup_str.as_ptr()),
        );

        let reset_pos_str = native_interop::wide_str(strings.reset_position);
        let _ = AppendMenuW(
            settings_menu,
            MENU_ITEM_FLAGS(0),
            IDM_RESET_POSITION as usize,
            PCWSTR::from_raw(reset_pos_str.as_ptr()),
        );

        // Show Decimals toggle
        let show_decimals_str = native_interop::wide_str(strings.show_decimals);
        let show_checked_flags = if {
            let state = lock_state();
            state.as_ref().map(|s| s.show_decimals).unwrap_or(true)
        } {
            MF_CHECKED
        } else {
            MENU_ITEM_FLAGS(0)
        };
        let _ = AppendMenuW(
            settings_menu,
            show_checked_flags,
            IDM_SHOW_DECIMALS as usize,
            PCWSTR::from_raw(show_decimals_str.as_ptr()),
        );

        let language_menu = CreatePopupMenu().unwrap();
        let system_label = native_interop::wide_str(strings.system_default);
        let system_flags = if language_override.is_none() {
            MF_CHECKED
        } else {
            MENU_ITEM_FLAGS(0)
        };
        let _ = AppendMenuW(
            language_menu,
            system_flags,
            IDM_LANG_SYSTEM as usize,
            PCWSTR::from_raw(system_label.as_ptr()),
        );

        for language in LanguageId::ALL {
            let id = match language {
                LanguageId::English => IDM_LANG_ENGLISH,
                LanguageId::Spanish => IDM_LANG_SPANISH,
                LanguageId::French => IDM_LANG_FRENCH,
                LanguageId::German => IDM_LANG_GERMAN,
                LanguageId::Japanese => IDM_LANG_JAPANESE,
            };
            let label_str = native_interop::wide_str(language.native_name());
            let flags = if language_override == Some(language) {
                MF_CHECKED
            } else {
                MENU_ITEM_FLAGS(0)
            };
            let _ = AppendMenuW(
                language_menu,
                flags,
                id as usize,
                PCWSTR::from_raw(label_str.as_ptr()),
            );
        }

        let language_label = native_interop::wide_str(strings.language);
        let _ = AppendMenuW(
            settings_menu,
            MF_POPUP,
            language_menu.0 as usize,
            PCWSTR::from_raw(language_label.as_ptr()),
        );

        let _ = AppendMenuW(settings_menu, MF_SEPARATOR, 0, PCWSTR::null());

        let version_label =
            version_action_label(strings, language, install_channel, &update_status);
        let version_str = native_interop::wide_str(&version_label);
        let version_flags = if matches!(update_status, UpdateStatus::Checking | UpdateStatus::Applying)
        {
            MF_GRAYED
        } else {
            MENU_ITEM_FLAGS(0)
        };
        let _ = AppendMenuW(
            settings_menu,
            version_flags,
            IDM_VERSION_ACTION as usize,
            PCWSTR::from_raw(version_str.as_ptr()),
        );

        let settings_label = native_interop::wide_str(strings.settings);
        let _ = AppendMenuW(
            menu,
            MF_POPUP,
            settings_menu.0 as usize,
            PCWSTR::from_raw(settings_label.as_ptr()),
        );

        let widget_label = native_interop::wide_str("Show Widget");
        let widget_flags = if widget_visible { MF_CHECKED } else { MENU_ITEM_FLAGS(0) };
        let _ = AppendMenuW(
            menu,
            widget_flags,
            tray_icon::IDM_TOGGLE_WIDGET as usize,
            PCWSTR::from_raw(widget_label.as_ptr()),
        );

        let _ = AppendMenuW(menu, MF_SEPARATOR, 0, PCWSTR::null());

        let exit_str = native_interop::wide_str(strings.exit);
        let _ = AppendMenuW(
            menu,
            MENU_ITEM_FLAGS(0),
            2,
            PCWSTR::from_raw(exit_str.as_ptr()),
        );

        let mut pt = POINT::default();
        let _ = GetCursorPos(&mut pt);
        let _ = SetForegroundWindow(hwnd);
        let _ = TrackPopupMenu(menu, TPM_RIGHTBUTTON, pt.x, pt.y, 0, hwnd, None);
        let _ = DestroyMenu(menu);
    }
}

/// Paint for non-embedded fallback (normal WM_PAINT path)
fn paint(hdc: HDC, hwnd: HWND) {
    let (is_dark, strings, session_pct, session_text, weekly_pct, weekly_text) = {
        let state = lock_state();
        match state.as_ref() {
            Some(s) => (
                s.is_dark,
                s.language.strings(),
                s.session_percent,
                s.session_text.clone(),
                s.weekly_percent,
                s.weekly_text.clone(),
            ),
            None => return,
        }
    };

    let accent = Color::from_hex("#D97757");
    let track = if is_dark {
        Color::from_hex("#444444")
    } else {
        Color::from_hex("#AAAAAA")
    };
    let text_color = if is_dark {
        Color::from_hex("#888888")
    } else {
        Color::from_hex("#404040")
    };
    let bg_color = if is_dark {
        Color::from_hex("#1C1C1C")
    } else {
        Color::from_hex("#F3F3F3")
    };

    unsafe {
        let mut client_rect = RECT::default();
        let _ = GetClientRect(hwnd, &mut client_rect);
        let width = client_rect.right - client_rect.left;
        let height = client_rect.bottom - client_rect.top;

        if width <= 0 || height <= 0 {
            return;
        }

        let mem_dc = CreateCompatibleDC(hdc);
        let mem_bmp = CreateCompatibleBitmap(hdc, width, height);
        let old_bmp = SelectObject(mem_dc, mem_bmp);

        paint_content(
            mem_dc,
            width,
            height,
            is_dark,
            &bg_color,
            &text_color,
            &accent,
            &track,
            strings,
            session_pct,
            &session_text,
            weekly_pct,
            &weekly_text,
        );

        let _ = BitBlt(hdc, 0, 0, width, height, mem_dc, 0, 0, SRCCOPY);

        SelectObject(mem_dc, old_bmp);
        let _ = DeleteObject(mem_bmp);
        let _ = DeleteDC(mem_dc);
    }
}

fn draw_row(
    hdc: HDC,
    x: i32,
    y: i32,
    label: &str,
    percent: f64,
    text: &str,
    accent: &Color,
    track: &Color,
) {
    let seg_w = sc(SEGMENT_W);
    let seg_h = sc(SEGMENT_H);
    let seg_gap = sc(SEGMENT_GAP);
    let corner_r = sc(CORNER_RADIUS);

    unsafe {
        let mut label_wide: Vec<u16> = label.encode_utf16().collect();
        let mut label_rect = RECT {
            left: x,
            top: y,
            right: x + sc(LABEL_WIDTH),
            bottom: y + seg_h,
        };
        let _ = DrawTextW(
            hdc,
            &mut label_wide,
            &mut label_rect,
            DT_LEFT | DT_VCENTER | DT_SINGLELINE,
        );

        let bar_x = x + sc(LABEL_WIDTH) + sc(LABEL_RIGHT_MARGIN);
        let percent_clamped = percent.clamp(0.0, 100.0);

        for i in 0..SEGMENT_COUNT {
            let seg_x = bar_x + i * (seg_w + seg_gap);
            let seg_start = (i as f64) * 10.0;
            let seg_end = seg_start + 10.0;

            let seg_rect = RECT {
                left: seg_x,
                top: y,
                right: seg_x + seg_w,
                bottom: y + seg_h,
            };

            if percent_clamped >= seg_end {
                draw_rounded_rect(hdc, &seg_rect, accent, corner_r);
            } else if percent_clamped <= seg_start {
                draw_rounded_rect(hdc, &seg_rect, track, corner_r);
            } else {
                draw_rounded_rect(hdc, &seg_rect, track, corner_r);
                let fraction = (percent_clamped - seg_start) / 10.0;
                let fill_width = (seg_w as f64 * fraction) as i32;
                if fill_width > 0 {
                    let fill_rect = RECT {
                        left: seg_x,
                        top: y,
                        right: seg_x + fill_width,
                        bottom: y + seg_h,
                    };
                    let rgn = CreateRoundRectRgn(
                        seg_rect.left,
                        seg_rect.top,
                        seg_rect.right + 1,
                        seg_rect.bottom + 1,
                        corner_r * 2,
                        corner_r * 2,
                    );
                    let _ = SelectClipRgn(hdc, rgn);
                    let brush = CreateSolidBrush(COLORREF(accent.to_colorref()));
                    FillRect(hdc, &fill_rect, brush);
                    let _ = DeleteObject(brush);
                    let _ = SelectClipRgn(hdc, HRGN::default());
                    let _ = DeleteObject(rgn);
                }
            }
        }

        let text_x = bar_x + SEGMENT_COUNT * (seg_w + seg_gap) - seg_gap + sc(BAR_RIGHT_MARGIN);
        let mut text_wide: Vec<u16> = text.encode_utf16().collect();
        let mut text_rect = RECT {
            left: text_x,
            top: y,
            right: text_x + sc(TEXT_WIDTH),
            bottom: y + seg_h,
        };
        let _ = DrawTextW(
            hdc,
            &mut text_wide,
            &mut text_rect,
            DT_LEFT | DT_VCENTER | DT_SINGLELINE,
        );
    }
}

fn draw_rounded_rect(hdc: HDC, rect: &RECT, color: &Color, radius: i32) {
    unsafe {
        let brush = CreateSolidBrush(COLORREF(color.to_colorref()));
        let rgn = CreateRoundRectRgn(
            rect.left,
            rect.top,
            rect.right + 1,
            rect.bottom + 1,
            radius * 2,
            radius * 2,
        );
        let _ = FillRgn(hdc, rgn, brush);
        let _ = DeleteObject(rgn);
        let _ = DeleteObject(brush);
    }
}