#include <FL/Fl.H>
#include <FL/Fl_Double_Window.H>
#include <FL/Fl_Box.H>
#include <FL/fl_draw.H>
#include <FL/Fl_Button.H>
#include <stdio.h>
#include <time.h>
#include <string>
#include <sstream>
#include <iostream>

Fl_Box *progress;
Fl_Button *status, *btnWork, *btnRest, *btnCurrent;
time_t startTime = 0, targetTime = -1, workTime = 60 * 60, restTime = 15 * 60;
char buff[20] = {0};

void parseTime(int time, int* hours, int *minutes, int *seconds) {
    *hours = time / 3600;
    time -= *hours * 3600;
    *minutes = time / 60;
    time -= *minutes * 60;
    *seconds = time;
    if(*hours > 99) *hours = 99;
}

void updateTime(int diffTime) {
    int h, m, s, th, tm, ts;
    parseTime(diffTime, &h, &m, &s);
    if(targetTime >= 0) {
        parseTime(targetTime, &th, &tm, &ts);
        snprintf(buff, 20, "%02d:%02d / %02d:%02d", h, m, th, tm);
    } else {
        snprintf(buff, 20, "%02d:%02d / --:--", h, m);
    }
    progress->label(buff);
}

void setState(const char *text, Fl_Color color, time_t time) {
    status->label(text);
    status->labelcolor(color);
    targetTime = time;
}

void onBtnClick(Fl_Widget* w, void* inner) {
    if(w == btnWork) setState("WORK", 0xFF0040FF, workTime);
    else if(w == btnRest) setState("REST", 0xAAFF00FF, restTime);
    else setState("AWAIT", 0x00FFFFFF, -1);
    btnCurrent = (Fl_Button*) w;
    startTime = time(NULL);
    updateTime(0);
}

void Update_CB(void* userdata) {
    int diffTime = time(NULL) - startTime;
    updateTime(diffTime);
    if(targetTime > 0 && diffTime > targetTime) onBtnClick((btnCurrent == btnWork) ? btnRest : btnWork, 0);
    Fl::repeat_timeout(1.0, Update_CB, (void*) 0);
}

int main() {
    Fl_Double_Window *win = new Fl_Double_Window(200, 130, "timer");
    win->color(0x333333FF);
    status = new Fl_Button(0, 5, 200, 50, 0);
    status->box(FL_NO_BOX);
    status->labelsize(60);
    status->labelcolor(0x00FFFFFF);
    status->labelfont(FL_BOLD + FL_ITALIC);
    status->labeltype(FL_SHADOW_LABEL);
    status->callback(&onBtnClick);

    progress = new Fl_Box(0, 55, 200, 20, 0);
    progress->box(FL_NO_BOX);
    progress->labelsize(20);
    progress->labelcolor(0x00FFFFFF);
    progress->labelfont(FL_BOLD + FL_ITALIC);
    progress->labeltype(FL_NORMAL_LABEL);

    btnWork = new Fl_Button(10, 80, 85, 40, "work");
    btnWork->callback(&onBtnClick);

    btnRest = new Fl_Button(105, 80, 85, 40, "rest");
    btnRest->callback(&onBtnClick);
    onBtnClick(0, 0);

    Fl::add_timeout(1.0, Update_CB, (void*) 0);
    win->show();
    return (Fl::run());
}