#include <libinput.h>
#include <linux/input.h>
#include "LinuxFrameBuffer.h"

using namespace Upp;


void LinuxFrameBuffer::WaitEvent(int ms)
{
    if (input.lib_inp == nullptr) return;
    
    auto fd = libinput_get_fd(input.lib_inp);
    
    fd_set set[1];
    FD_ZERO(set);
    FD_SET(fd, set);
    timeval tval = { ms / 1000, ms % 1000 * 1000 };
    if (select(fd + 1, set, nullptr, nullptr, &tval) > 0){
        libinput_dispatch(input.lib_inp);
    }
}


bool LinuxFrameBuffer::IsWaitingEvent()
{
    return input.lib_inp != nullptr && libinput_next_event_type(input.lib_inp) != LIBINPUT_EVENT_NONE;
}

#define CHMOD(mod, mask, press) do{ if (press) mod |= mask; else mod &= ~mask; }while(false)

bool LinuxFrameBuffer::ProcessEvent(bool *quit)
{
    if (input.lib_inp == nullptr) return false;
    struct libinput_event *event;
    bool ret = false;
    if((event = libinput_get_event(input.lib_inp)) != nullptr){
        
        switch(libinput_event_get_type(event)){

            case LIBINPUT_EVENT_KEYBOARD_KEY:
            {
                struct libinput_event_keyboard *key_event = libinput_event_get_keyboard_event(event);
                auto key = libinput_event_keyboard_get_key(key_event);
                bool pressed = (libinput_event_keyboard_get_key_state(key_event) == LIBINPUT_KEY_STATE_PRESSED);
                switch(key){
                    case KEY_LEFTALT:       CHMOD(input.keyboard.modkeys, KM_LALT, pressed); break;
                    case KEY_RIGHTALT:      CHMOD(input.keyboard.modkeys, KM_RALT, pressed); break;
                    case KEY_LEFTCTRL:      CHMOD(input.keyboard.modkeys, KM_LCTRL, pressed); break;
                    case KEY_RIGHTCTRL:     CHMOD(input.keyboard.modkeys, KM_RCTRL, pressed); break;
                    case KEY_LEFTSHIFT:     CHMOD(input.keyboard.modkeys, KM_LSHIFT, pressed); break;
                    case KEY_RIGHTSHIFT:    CHMOD(input.keyboard.modkeys, KM_RSHIFT, pressed); break;
                }

                auto upp_scan = TranslateScanCode(key);
                if (upp_scan) Ctrl::DoKeyFB(upp_scan | (!pressed ? K_KEYUP : 0), 1);
                else { LOG(Format("Scan code %d was not translated to K_*, see input-event-codes.h", (int)key)); }

                if (pressed){
                    WString txt = ScanCodeToUtf8(key).ToWString();
                    for (int i = 0; i < txt.GetCount(); i++) {
                        if (txt[i] >= ' ')  Ctrl::DoKeyFB(txt[i], 1);
                    }
                }
            }
            break;
                
            case LIBINPUT_EVENT_POINTER_MOTION:
            {
                struct libinput_event_pointer *motion_event = libinput_event_get_pointer_event(event);
                input.mouse.pos.x += libinput_event_pointer_get_dx(motion_event);
                input.mouse.pos.y += libinput_event_pointer_get_dy(motion_event);
                input.mouse.pos.x = minmax(input.mouse.pos.x, 0, screen.GetSize().cx);
                input.mouse.pos.y = minmax(input.mouse.pos.y, 0, screen.GetSize().cy);
                Ctrl::DoMouseFB(Ctrl::MOUSEMOVE, input.mouse.pos);
            }
            break;
            
            case LIBINPUT_EVENT_POINTER_BUTTON:
            {
                struct libinput_event_pointer *button_event = libinput_event_get_pointer_event(event);
                auto button = libinput_event_pointer_get_button(button_event);
                auto state = libinput_event_pointer_get_button_state(button_event);
                switch(state){
                    
                    case LIBINPUT_BUTTON_STATE_PRESSED:
                        switch(button){
                            case BTN_LEFT: input.mouse.buttons |= (1<<0); Ctrl::DoMouseFB(Ctrl::LEFTDOWN, input.mouse.pos); break;
                            case BTN_RIGHT: input.mouse.buttons |= (1<<1); Ctrl::DoMouseFB(Ctrl::RIGHTDOWN, input.mouse.pos); break;
                            case BTN_MIDDLE: input.mouse.buttons |= (1<<2); Ctrl::DoMouseFB(Ctrl::MIDDLEDOWN, input.mouse.pos); break;
                        }
                        break;
                    
                    case LIBINPUT_BUTTON_STATE_RELEASED:
                        switch(button){
                            case BTN_LEFT: input.mouse.buttons &= ~(1<<0); Ctrl::DoMouseFB(Ctrl::LEFTUP, input.mouse.pos); break;
                            case BTN_RIGHT: input.mouse.buttons &= ~(1<<1); Ctrl::DoMouseFB(Ctrl::RIGHTUP, input.mouse.pos); break;
                            case BTN_MIDDLE: input.mouse.buttons &= ~(1<<2); Ctrl::DoMouseFB(Ctrl::MIDDLEUP, input.mouse.pos); break;
                        }
                        break;
                }
            }
            break;
                
            case LIBINPUT_EVENT_POINTER_AXIS:
            {
                struct libinput_event_pointer *axis_event = libinput_event_get_pointer_event (event);
                auto source = libinput_event_pointer_get_axis_source(axis_event);
                const auto axis = LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL;
                if (libinput_event_pointer_has_axis(axis_event, axis) && source == LIBINPUT_POINTER_AXIS_SOURCE_WHEEL){
                    auto delta = libinput_event_pointer_get_axis_value_discrete(axis_event, axis);
                    Ctrl::DoMouseFB(Ctrl::MOUSEWHEEL, input.mouse.pos, -120*delta);
                }
            }
            break;

        }
        
        libinput_event_destroy(event);
        libinput_dispatch(input.lib_inp);
        ret = true;
    }
    
    return ret;
}