/*
 * CommandParser.cpp
 *
 * Copyright (C) 2008 Matthias Schiffer <matthias@gamezock.de>
 *
 * This program 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.
 *
 * This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include "CommandParser.h"
#include "Requests/CoreStatusRequest.h"
#include "Requests/DaemonListRequest.h"
#include "Requests/DaemonStatusRequest.h"
#include <Common/Exception.h>
#include <Common/Requests/DisconnectRequest.h>
#include <Net/Packets/HostStatusPacket.h>
#include <Net/Packets/NameListPacket.h>

#include <iostream>
#include <cstdio>

namespace Mad {
namespace Client {

const CommandParser::Command CommandParser::commands[] = {
    {{"help", "?", 0}, "help [command]", "Displays usage information about commands", "Displays usage information about a command. If no command is given, a list of all available commands is displayed.", &CommandParser::helpCommand},
    {{"list_hosts", "hosts", 0}, "list_hosts", "Lists the currently active hosts", "Lists the currently active hosts", &CommandParser::listHostsCommand},
    {{"status", "st", 0}, "status [host]", "Displays status information", "Displays host status information. If no host is given, server status information is displayed.", &CommandParser::statusCommand},
    {{"exit", "quit", 0}, "exit", "Closes the connection and quits the client", "Closes the connection and quits the client.", &CommandParser::exitCommand},
    {{0}, 0, 0, 0, 0}
};

const CommandParser::Command* CommandParser::findCommand(const std::string& command) {
  for(int i = 0; commands[i].commands[0] != 0; ++i) {
    for(int j = 0; commands[i].commands[j] != 0; ++j) {
      if(command == commands[i].commands[j]) {
        return &commands[i];
      }
    }
  }

  return 0;
}

void CommandParser::printUsage(const std::string& command) {
  const CommandParser::Command *cmd = findCommand(command);

  if(cmd)
    std::cerr << "Usage: " << cmd->cmdline << std::endl << std::endl;
}

void CommandParser::printHostStatus(const Net::Packets::HostStatusPacket &packet) {
  if(packet.getUptime()) {
    unsigned long days = packet.getUptime()/86400;
    unsigned long hours = (packet.getUptime()%86400)/3600;
    unsigned long minutes = (packet.getUptime()%3600)/60;

    std::printf("\tUptime:\t\t");

    if(days) std::printf("%lu days ", days);

    std::printf("%lu:%02lu", hours, minutes);

    if(packet.getIdleTime())
      std::printf(" (load average: %.1f%%)", 100.0f-(packet.getIdleTime()*100.0f/packet.getUptime()));

    std::printf("\n\n");
  }

  if(packet.getTotalMem() && packet.getFreeMem()) {
    const std::string units[] = {
        "kB", "MB", "GB", "TB", ""
    };

    unsigned unit = 0;
    float totalMem = packet.getTotalMem(), usedMem = packet.getTotalMem()-packet.getFreeMem();

    while(totalMem >= 1024 && !units[unit+1].empty()) {
      ++unit;
      totalMem /= 1024;
      usedMem /= 1024;
    }

    std::printf("\tMemory usage:\t%.*f/%.*f %s", (usedMem < 10) ? 2 : 1, usedMem, (totalMem < 10) ? 2 : 1, totalMem, units[unit].c_str());
    std::printf(" (%.1f%%)\n", usedMem*100.0f/totalMem);

    if(packet.getTotalSwap() && packet.getFreeSwap()) {
      unit = 0;
      totalMem = packet.getTotalSwap(); usedMem = packet.getTotalSwap()-packet.getFreeSwap();

      while(totalMem >= 1024 && !units[unit+1].empty()) {
        ++unit;
        totalMem /= 1024;
        usedMem /= 1024;
      }

      std::printf("\tSwap usage:\t%.*f/%.*f %s", (usedMem < 10) ? 2 : 1, usedMem, (totalMem < 10) ? 2 : 1, totalMem, units[unit].c_str());
      std::printf(" (%.1f%%)\n", usedMem*100.0f/totalMem);
    }

    std::printf("\n");
  }
}

void CommandParser::helpCommand(const std::vector<std::string> &args) {
  if(args.size() == 1) {
    std::cout << "Available commands:" << std::endl << std::endl;

    for(int i = 0; commands[i].commands[0] != 0; ++i) {
      std::cout << commands[i].commands[0];

      for(int j = 1; commands[i].commands[j] != 0; ++j)
        std::cout << ", " << commands[i].commands[j];

      std::cout << std::endl << "\t" << commands[i].desc << std::endl;
    }
  }
  else if(args.size() == 2) {
    const Command* command = findCommand(args[1]);

    if(command) {
      std::cout << "Usage: " << command->cmdline << std::endl << std::endl;
      std::cout << command->longdesc << std::endl << std::endl;
    }
    else
      std::cerr << args[0] << ": Command '" << args[1] << "' doesn't exist." << std::endl << std::endl;
  }
  else {
    std::cerr << args[0] << ": Too many arguments." << std::endl;
    printUsage("help");
  }
}

void CommandParser::listHostsCommand(const std::vector<std::string>&) {
  activeRequests++;

  Requests::DaemonListRequest::send(connection, sigc::mem_fun(this, &CommandParser::daemonListRequestFinished));
}

void CommandParser::statusCommand(const std::vector<std::string> &args) {
  if(args.size() == 1)
    Requests::CoreStatusRequest::send(connection, sigc::mem_fun(this, &CommandParser::coreStatusRequestFinished));
  else if(args.size() == 2)
    Requests::DaemonStatusRequest::send(connection, sigc::mem_fun(this, &CommandParser::daemonStatusRequestFinished), sigc::mem_fun(this, &CommandParser::errorCallback), args[1]);
  else {
    std::cerr << args[0] << ": Too many arguments." << std::endl;
    printUsage("status");
    return;
  }

  activeRequests++;
}

void CommandParser::exitCommand(const std::vector<std::string>&) {
  activeRequests++;
  disconnect = true;

  Common::Requests::DisconnectRequest::send(connection, sigc::mem_fun(this, &CommandParser::requestFinished));
}

void CommandParser::coreStatusRequestFinished(const Net::Packets::HostStatusPacket &packet) {
  std::cout << "Server status:" << std::endl;

  printHostStatus(packet);

  requestFinished();
}

void CommandParser::daemonListRequestFinished(const Net::Packets::NameListPacket &packet) {
  const std::vector<std::string>& hosts = packet.getNameList();

  if(hosts.empty()) {
    std::cout << "There aren't any active hosts." << std::endl << std::endl;
  }
  else {
    std::cout << "Active hosts:" << std::endl;

    for(std::vector<std::string>::const_iterator host = hosts.begin(); host != hosts.end(); ++host)
      std::cout << "\t" << *host << std::endl;

    std::cout << std::endl;
  }

  requestFinished();
}

void CommandParser::daemonStatusRequestFinished(const Net::Packets::HostStatusPacket &packet) {
  std::cout << "Host status:" << std::endl;

  printHostStatus(packet);

  requestFinished();
}

void CommandParser::errorCallback(const Common::Exception &exception) {
  std::cerr << "An error occurred during your request." << std::endl;
  std::cerr << "Error code: " << exception.getErrorCode() << std::endl << std::endl;

  requestFinished();
}

bool CommandParser::split(const std::string &str, std::vector<std::string> &ret) {
  std::string temp;
  bool quoteSingle = false, quoteDouble = false, escape = false;

  size_t beg = 0;

  for(size_t cur = 0; cur < str.length(); ++cur) {
    if(!escape) {
      if(str[cur] == ' ' && !quoteSingle && !quoteDouble) {
        if(cur == beg && temp.empty()) {
          ++beg;
        }
        else {
          temp += str.substr(beg, cur-beg);
          ret.push_back(temp);
          temp.clear();
          beg = cur+1;
        }

        continue;
      }

      if(str[cur] == '"' && !quoteSingle) {
        temp += str.substr(beg, cur-beg);
        beg = cur+1;

        quoteDouble = !quoteDouble;
        continue;
      }
      if(str[cur] == '\'' && !quoteDouble) {
        temp += str.substr(beg, cur-beg);
        beg = cur+1;

        quoteSingle = !quoteSingle;
        continue;
      }

      if(str[cur] == '\\') {
        escape = true;
        continue;
      }
    }

    if(escape && ((!quoteSingle && !quoteDouble) || (quoteSingle && str[cur] == '\'') || (quoteDouble && (str[cur] == '"' || str[cur] == '\\')))) {
      temp += str.substr(beg, cur-beg-1);
      beg = cur;
    }

    escape = false;
  }

  temp += str.substr(beg, std::string::npos);
  ret.push_back(temp);

  return true;
}

bool CommandParser::parse(const std::string &cmd) {
  std::vector<std::string> splitCmd;

  split(cmd, splitCmd);

  if(splitCmd.empty())
    return true;

  const Command* command = findCommand(splitCmd[0]);

  if(command)
    (this->*command->funcPtr)(splitCmd);
  else
    std::cerr << "Unknown command '" << splitCmd[0] << "'." << std::endl << std::endl;

  return true;
}

}
}