/*
 * SystemBackendPosix.h
 *
 * 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/>.
 */

#ifndef MAD_MODULES_SYSTEMBACKENDPOSIX_H_
#define MAD_MODULES_SYSTEMBACKENDPOSIX_H_

#include <Common/SystemBackend.h>

#include <map>
#include <string>
#include <vector>

#include <sys/types.h>
#include <sigc++/slot.h>
#include <sigc++/adaptors/hide.h>

namespace Mad {
namespace Modules {

class SystemBackendPosix : private Common::SystemBackend {
  private:
    static SystemBackendPosix *backend;
    static std::map<pid_t, sigc::slot<void, int> > processes;

    static std::map<pid_t, sigc::slot<void, int, const std::string&> > processesWithOutput;
    static std::map<pid_t, int> processesWOHandles;
    static std::map<pid_t, std::string > processesWOOutput;

    static void setChildHandler();

    static void childHandler(int);

    static void outputHandler(short events, pid_t pid);

    static std::pair<char**, char**> makeArgs(const std::string &filename, const std::vector<std::string> &argv, const std::vector<std::string> &env);
    static void destroyArgs(std::pair<char**, char**> args);

    SystemBackendPosix() {
      setChildHandler();
    }

    void fsInfoCallback(int, const std::string &output, const sigc::slot<void, const std::vector<Common::SystemManager::FSInfo>& > &callback);

  protected:
    virtual bool getFSInfo(const sigc::slot<void, const std::vector<Common::SystemManager::FSInfo>& > &callback);

    virtual bool shutdown(const sigc::slot<void> &callback) {return exec(sigc::hide(callback), "/sbin/halt");}
    virtual bool reboot(const sigc::slot<void> &callback) {return exec(sigc::hide(callback), "/sbin/reboot");}

  public:
    ~SystemBackendPosix();

    static void registerBackend() {
      if(backend)
        return;

      backend = new SystemBackendPosix();
      Common::SystemManager::get()->registerBackend(backend);
    }

    static void unregisterBackend() {
      if(!backend)
        return;

      Common::SystemManager::get()->unregisterBackend(backend);
      delete backend;
      backend = 0;
    }

    static bool exec(const sigc::slot<void, int> &resultHandler, const std::string &filename, const std::vector<std::string> &argv = std::vector<std::string>(),
        const std::vector<std::string> &env = std::vector<std::string>());

    static bool execWithOutput(const sigc::slot<void, int, const std::string&> &resultHandler, const std::string &filename, const std::vector<std::string> &argv = std::vector<std::string>(),
        const std::vector<std::string> &env = std::vector<std::string>());
};

}
}

#endif /* MAD_MODULES_SYSTEMBACKENDPOSIX_H_ */