/*
** Copyright (C) Katrin Lang <mail@katrinlang.de>
** Licensed under GPL v3 or later
*/

#include <ncursesw/ncurses.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <locale.h>

int main(){

  int rainbow[]= {COLOR_RED, COLOR_YELLOW, COLOR_GREEN, COLOR_CYAN, COLOR_BLUE, COLOR_MAGENTA};

  setlocale(LC_ALL,"");
  initscr();			/* Start curses mode 		*/
  if(has_colors() == FALSE){   /* FALSE is defined already in ncurses.h */
    endwin();
    printf("Your terminal does not support color\n");
    exit(EXIT_FAILURE);
  }

  /*
    Curses initializes all the colors supported by terminal when start_color() is called. These can be accessed by the define constants like COLOR_BLACK etc. Now to actually start using colors, you have to define pairs. Colors are always used in pairs. That means you have to use the function init_pair() to define the foreground and background for the pair number you give. After that that pair number can be used as a normal attribute with COLOR_PAIR()function. This may seem to be cumbersome at first. But this elegant solution allows us to manage color pairs very easily. 
  */
  start_color();
  
  init_pair(COLOR_RED, COLOR_RED, COLOR_BLACK);
  init_pair(COLOR_YELLOW, COLOR_YELLOW, COLOR_BLACK);
  init_pair(COLOR_GREEN, COLOR_GREEN, COLOR_BLACK);
  init_pair(COLOR_CYAN, COLOR_CYAN, COLOR_BLACK);
  init_pair(COLOR_BLUE, COLOR_BLUE, COLOR_BLACK);
  init_pair(COLOR_MAGENTA, COLOR_MAGENTA, COLOR_BLACK);

  curs_set(0); //remove cursor

  for(int i= 0; i<sizeof(rainbow)/sizeof(int); i++){
    attron(COLOR_PAIR(rainbow[i]));
    addstr("\u2588");
    attroff(COLOR_PAIR(rainbow[i]));
  } 
  addstr("\n");
  refresh();
  getch();  //wait for input
  endwin();
  return 0;
}