#include "pch.h"
#include "resource.h"
#include "settings_window.h"
#include "tray_icon.h"
#include <Windows.h>
#include <common/common.h>

extern "C" IMAGE_DOS_HEADER __ImageBase;

namespace
{
    HWND tray_icon_hwnd = NULL;

    // Message code that Windows will use for tray icon notifications.
    UINT wm_icon_notify = 0;

    // Contains the Windows Message for taskbar creation.
    UINT wm_taskbar_restart = 0;
    UINT wm_run_on_main_ui_thread = 0;

    NOTIFYICONDATAW tray_icon_data;
    bool tray_icon_created = false;

    bool about_box_shown = false;

    HMENU h_menu = nullptr;
    HMENU h_sub_menu = nullptr;
}

// Struct to fill with callback and the data. The window_proc is responsible for cleaning it.
struct run_on_main_ui_thread_msg
{
    main_loop_callback_function _callback;
    PVOID data;
};

bool dispatch_run_on_main_ui_thread(main_loop_callback_function _callback, PVOID data)
{
    if (tray_icon_hwnd == NULL)
    {
        return false;
    }
    struct run_on_main_ui_thread_msg* wnd_msg = new struct run_on_main_ui_thread_msg();
    wnd_msg->_callback = _callback;
    wnd_msg->data = data;

    PostMessage(tray_icon_hwnd, wm_run_on_main_ui_thread, 0, (LPARAM)wnd_msg);

    return true;
}

LRESULT __stdcall tray_icon_window_proc(HWND window, UINT message, WPARAM wparam, LPARAM lparam)
{
    switch (message)
    {
    case WM_CREATE:
        if (wm_taskbar_restart == 0)
        {
            tray_icon_hwnd = window;
            wm_taskbar_restart = RegisterWindowMessageW(L"TaskbarCreated");
            wm_run_on_main_ui_thread = RegisterWindowMessage(L"RunOnMainThreadCallback");
        }
        break;
    case WM_DESTROY:
        if (tray_icon_created)
        {
            Shell_NotifyIcon(NIM_DELETE, &tray_icon_data);
            tray_icon_created = false;
        }
        PostQuitMessage(0);
        break;
    case WM_CLOSE:
        DestroyWindow(window);
        break;
    case WM_COMMAND:
        switch (wparam)
        {
        case ID_SETTINGS_MENU_COMMAND:
            open_settings_window();
            break;
        case ID_EXIT_MENU_COMMAND:
            if (h_menu)
            {
                DestroyMenu(h_menu);
            }
            DestroyWindow(window);
            break;
        case ID_ABOUT_MENU_COMMAND:
            if (!about_box_shown)
            {
                about_box_shown = true;
                std::wstring about_msg = L"PowerToys\nVersion " + get_product_version() + L"\n\xa9 2019 Microsoft Corporation";
                MessageBox(nullptr, about_msg.c_str(), L"About PowerToys", MB_OK);
                about_box_shown = false;
            }
            break;
        }
        break;
    // Shell_NotifyIcon can fail when we invoke it during the time explorer.exe isn't present/ready to handle it.
    // We'll also never receive wm_taskbar_restart message if the first call to Shell_NotifyIcon failed, so we use
    // WM_WINDOWPOSCHANGING which is always received on explorer startup sequence.
    case WM_WINDOWPOSCHANGING:
    {
        if (!tray_icon_created)
        {
            tray_icon_created = Shell_NotifyIcon(NIM_ADD, &tray_icon_data) == TRUE;
        }
        break;
    }
    default:
        if (message == wm_icon_notify)
        {
            switch (lparam)
            {
            case WM_LBUTTONUP:
            {
                open_settings_window();
                break;
            }
            case WM_RBUTTONUP:
            case WM_CONTEXTMENU:
            {
                if (!h_menu)
                {
                    h_menu = LoadMenu(reinterpret_cast<HINSTANCE>(&__ImageBase), MAKEINTRESOURCE(ID_TRAY_MENU));
                }
                if (!h_sub_menu)
                {
                    h_sub_menu = GetSubMenu(h_menu, 0);
                }
                POINT mouse_pointer;
                GetCursorPos(&mouse_pointer);
                SetForegroundWindow(window); // Needed for the context menu to disappear.
                TrackPopupMenu(h_sub_menu, TPM_CENTERALIGN | TPM_BOTTOMALIGN, mouse_pointer.x, mouse_pointer.y, 0, window, nullptr);
            }
            break;
            }
        }
        else if (message == wm_run_on_main_ui_thread)
        {
            if (lparam != NULL)
            {
                struct run_on_main_ui_thread_msg* msg = (struct run_on_main_ui_thread_msg*)lparam;
                msg->_callback(msg->data);
                delete msg;
                lparam = NULL;
            }
            break;
        }
        else if (message == wm_taskbar_restart)
        {
            tray_icon_created = Shell_NotifyIcon(NIM_ADD, &tray_icon_data) == TRUE;
            break;
        }
    }
    return DefWindowProc(window, message, wparam, lparam);
}

void start_tray_icon()
{
    auto h_instance = reinterpret_cast<HINSTANCE>(&__ImageBase);
    auto icon = LoadIcon(h_instance, MAKEINTRESOURCE(APPICON));
    if (icon)
    {
        UINT id_tray_icon = wm_icon_notify = RegisterWindowMessageW(L"WM_PowerToysIconNotify");

        static LPCWSTR class_name = L"PToyTrayIconWindow";
        WNDCLASS wc = {};
        wc.hCursor = LoadCursor(nullptr, IDC_ARROW);
        wc.hInstance = h_instance;
        wc.lpszClassName = class_name;
        wc.style = CS_HREDRAW | CS_VREDRAW;
        wc.lpfnWndProc = tray_icon_window_proc;
        wc.hIcon = icon;
        RegisterClass(&wc);
        auto hwnd = CreateWindowW(wc.lpszClassName,
                                  L"PToyTrayIconWindow",
                                  WS_OVERLAPPEDWINDOW | WS_POPUP,
                                  CW_USEDEFAULT,
                                  CW_USEDEFAULT,
                                  CW_USEDEFAULT,
                                  CW_USEDEFAULT,
                                  nullptr,
                                  nullptr,
                                  wc.hInstance,
                                  nullptr);
        WINRT_VERIFY(hwnd);

        memset(&tray_icon_data, 0, sizeof(tray_icon_data));
        tray_icon_data.cbSize = sizeof(tray_icon_data);
        tray_icon_data.hIcon = icon;
        tray_icon_data.hWnd = hwnd;
        tray_icon_data.uID = id_tray_icon;
        tray_icon_data.uCallbackMessage = wm_icon_notify;
        wcscpy_s(tray_icon_data.szTip, sizeof(tray_icon_data.szTip) / sizeof(WCHAR), L"PowerToys");
        tray_icon_data.uFlags = NIF_ICON | NIF_TIP | NIF_MESSAGE;

        tray_icon_created = Shell_NotifyIcon(NIM_ADD, &tray_icon_data) == TRUE;
    }
}

void stop_tray_icon()
{
    if (tray_icon_created)
    {
        SendMessage(tray_icon_hwnd, WM_CLOSE, 0, 0);
    }
}
