// Unix terminal demo of weemenu.

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <cstdio>
#include <termios.h>
#include <unistd.h>
#include <sys/select.h>

#include "weemenu.h"

using std::cout;
using std::cerr;
using std::endl;
using std::flush;

const int stdin_fd = 1;
int n = 0;
bool done = false;

// Super cheesy, but should be fine for now.
struct my_noncurses {
  static void
  clear(void *)
  {
    cout << "\n\n\n\n\033[H\033[2J";
  }

  static void
  print(void *, int y, const char *s)
  {
    if (-4 <= y && y <= 4) cout << s;
  }

  static void
  println(void *, int y, const char *line)
  {
    if (-4 <= y && y <= 4) cout << line << "    \n";
  }

  static void
  update(void *)
  {
    cout << flush;
  }
};

template<typename menu_t>
struct my_menu {
  static void 
  main_tree(menu_t& m)
  {
    // Menu item actions:
    if (m.item("Increment")) n++;
    if (m.item("Decrement")) n--;

    // Dynamic menu item labels:
    char buf[12];
    sprintf(buf, "n = %d", n);
    if (m.item(buf)) n = 0;

    // Nested menus:
    if (m.nest("Quit")) {
      if (m.item("Don't quit")) m.go_to_root();
      if (m.item("Really quit")) done = true;
      m.end();
    }

    // Arbitrarily nested menus, up to 8 levels:
    if (m.nest("Enter tunnel")) {
      if (m.nest("Open door")) {
        if (m.nest("Use key")) {
          m.item("Turn clockwise");
          if (m.nest("Turn counterclockwise")) {
            if (m.item("You are home!")) m.go_to_root();
            m.end();
          }
          m.end();
        }
        m.item("Use lock pick");
        m.end();
      }
      if (m.nest("Cross stream")) {
        if (m.item("You drowned.")) m.go_to_root();
        m.end();
      }
      m.end();
    }

    // Dynamically generated menu items (but be careful!  You can get
    // warped to some other menu if the structure of some menu up the
    // tree from you changes):
    if (m.nest("The N items")) {
      for (int i = 0; i < n; i++) {
        sprintf(buf, "item %d", i);
        m.item(buf);
      }
      m.end();
    }
    if (m.item("n ← 100")) n = 100;
    m.end();
  }
};

void
interact_with_menus()
{
  weemenu<my_noncurses, my_menu<weeweemenu<my_noncurses, 5> >, 5> menu;
  while (!done) {
    menu.draw();

    // This busywaits, checking the keyboard at 50Hz:
    char c;
    while (0 == read(stdin_fd, &c, 1)) usleep(20*1000);

    switch (c) {
    case 'h': case 'D': menu.left(); break;
    case 'j': case 'B': menu.down(); break;
    case 'k': case 'A': menu.up(); break;
    case 'l': case 'C': menu.right(); break;
    default: /* no op */ break;
    }
  }
  cout << "sizeof menu is " << sizeof(menu) << "\n";
}

static void
panic(const char *reason)
{
  cerr << "panic: " << reason << endl;
  abort();
}

/* because curses makes me curse; ganked from my actor.c */
static struct termios
my_cbreak(int fd)
{
  struct termios new_termios, old_termios;
  if (tcgetattr(fd, &old_termios) < 0) panic("tcgetattr");

  new_termios = old_termios;
  new_termios.c_lflag &= ~(ECHO | ICANON);
  new_termios.c_cc[VMIN] = 0;
  new_termios.c_cc[VTIME] = 0;
  if (tcsetattr(fd, TCSANOW, &new_termios) < 0) panic("tcsetattr");
  return old_termios;
}

int
main(int argc, char **argv)
{
  struct termios old_termios = my_cbreak(stdin_fd);
  interact_with_menus();
  tcsetattr(stdin_fd, TCSANOW, &old_termios);
  return 0;
}