/*
 * Plain launcher program for Jay Bromley's Xkeyboard library.
 *
 * Copyright (C) 2010 by Sergey Mironov <ierton@gmail.com>
 *
 * This file is part of Xkb-switch.
 * Xkb-switch is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Xkb-switch is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Xkb-switch. If not, see <http://www.gnu.org/licenses/>.
 */
#include <X11/XKBlib.h>

#include <iostream>
#include <algorithm>
#include <sstream>

#include "XKeyboard.h"
#include "XKbSwitch.hpp"

using namespace std;
using namespace kb;

void usage()
{
  cerr << "Usage: xkb-switch -s ARG            Sets current layout group to ARG" << endl;
  cerr << "       xkb-switch -l|--list         Displays all layout groups" << endl;
  cerr << "       xkb-switch -h|--help         Displays this message" << endl;
  cerr << "       xkb-switch -v|--version      Shows version number" << endl;
  cerr << "       xkb-switch -w|--wait [-p]    Waits for group change" << endl;
  cerr << "       xkb-switch -W                Infinitely waits for group change, prints group names to stdout" << endl;
  cerr << "       xkb-switch -n|--next         Switch to the next layout group" << endl;
  cerr << "       xkb-switch [-p]              Displays current layout group" << endl;
}

string print_layouts(const string_vector& sv)
{
  ostringstream oss;
  bool fst = true;

  oss << "[";
  for(string_vector::const_iterator i=sv.begin(); i!=sv.end(); i++) {
    if(!fst) oss << " ";
    oss << *i;
    fst = false;
  }
  oss << "]";
  return oss.str();
}

int main( int argc, char* argv[] )
{
	string_vector syms;

	using namespace std;
  try {
    int m_cnt = 0;
    int m_wait = 0;
    int m_lwait = 0;
    int m_print = 0;
    int m_next = 0;
    int m_list = 0;
    string newgrp;

    for(int i=1; i<argc; i) {
      string arg(argv[i++]);
      if(arg == "-s") {
        CHECK_MSG(i<argc, "Argument expected");
        newgrp=argv[i++];
        m_cnt++;
      }
      else if(arg == "-l" || arg == "--list") {
        m_list = 1;
        m_cnt++;
      }
      else if(arg == "-v" || arg=="--version") {
        cerr << "xkb-switch " << XKBSWITCH_VERSION << endl;
        return 0;
      }
      else if(arg == "-w" || arg == "--wait") {
        m_wait = 1;
        m_cnt++;
      }
      else if(arg == "-W" || arg == "--longwait") {
        m_lwait = 1;
        m_cnt++;
      }
      else if(arg == "-p" || arg == "--print") {
        m_print = 1;
        m_cnt++;
      }
      else if(arg == "-n" || arg == "--next") {
        m_next = 1;
        m_cnt++;
      }
      else if(arg == "-h" || arg == "--help") {
        usage();
        return 1;
      }
      else {
        THROW_MSG("Invalid argument: '" << arg << "'. Check --help.");
      }
    }

    if(m_list || m_lwait || !newgrp.empty())
      CHECK_MSG(m_cnt==1, "Invalid flag combination. Try --help.");

    // Default action
    if(m_cnt==0)
      m_print = 1;

    XKeyboard xkb;
    xkb.open_display();

    if(m_wait) {
      xkb.wait_event();
    }

    if(m_lwait) {
      while(true) {
        xkb.wait_event();
        xkb.build_layout(syms);
        cout << syms.at(xkb.get_group()) << endl;
      }
    }

    if (m_lwait)
      syms.clear();

    xkb.build_layout(syms);

    if (m_next) {
      CHECK_MSG(!syms.empty(), "No layout groups configured");
      const string nextgrp = syms.at(xkb.get_group());
      string_vector::iterator i = find(syms.begin(), syms.end(), nextgrp);
      if (++i == syms.end()) i = syms.begin();
      xkb.set_group(i - syms.begin());
    }
    else if(!newgrp.empty()) {
      string_vector::iterator i = find(syms.begin(), syms.end(), newgrp);
      CHECK_MSG(i!=syms.end(),
        "Group '" << newgrp << "' is not supported by current layout. Try xkb-switch -l.");
      xkb.set_group(i-syms.begin());
    }

    if(m_print) {
      cout << syms.at(xkb.get_group()) << endl;
    }

    if(m_list) {
      for(int i=0; i<syms.size(); i++) {
        cout << syms[i] << endl;
      }
    }
    return 0;
  }
  catch(std::exception & err) {
    cerr << "xkb-switch: " << err.what() << endl;
    // TODO: don't print syms if they are not yet collected
    cerr << "xkb-switch: layouts: " << print_layouts(syms) << endl;
    return 2;
  }
}