/*
 *    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 2 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, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/*
 *    Author : Maxim Mamontov <faust@stargazer.dp.ua>
 */

#include "options.h"

#include "action.h"
#include "parser_state.h"

#include "stg/common.h"

#include <fstream>
#include <sstream>
#include <iostream>
#include <functional>
#include <algorithm>

#include <unistd.h>

namespace
{

template <class C>
void ReadConfigFile(const std::string & filePath, void (C::* callback)(const std::string&, const std::string&), C * obj)
{
std::ifstream stream(filePath.c_str());
std::string line;
size_t num = 0;
while (std::getline(stream, line))
    {
    ++num;
    line = Trim(line);
    std::string::size_type pos = line.find_first_of('#');
    if (pos != std::string::npos)
        line = line.substr(0, pos);
    if (line.empty())
        continue;
    pos = line.find_first_of('=');
    if (pos == std::string::npos)
        {
        std::ostringstream error;
        error << "Bad file format, missing '=' in '" << filePath << ":" << num << "'.";
        throw std::runtime_error(error.str().c_str());
        }
    (obj->*callback)(Trim(line.substr(0, pos)), Trim(line.substr(pos + 1, line.length() - pos - 1)));
    }
}

} // namespace anonymous

using SGCONF::OPTION;
using SGCONF::OPTION_BLOCK;
using SGCONF::OPTION_BLOCKS;
using SGCONF::ACTION;
using SGCONF::PARSER_STATE;

OPTION::OPTION(const std::string & shortName,
               const std::string & longName,
               ACTION * action,
               const std::string & description)
    : m_shortName(shortName),
      m_longName(longName),
      m_action(action),
      m_description(description)
{
}

OPTION::OPTION(const std::string & longName,
               ACTION * action,
               const std::string & description)
    : m_longName(longName),
      m_action(action),
      m_description(description)
{
}

OPTION::OPTION(const OPTION & rhs)
    : m_shortName(rhs.m_shortName),
      m_longName(rhs.m_longName),
      m_action(rhs.m_action->Clone()),
      m_description(rhs.m_description)
{
}

OPTION::~OPTION()
{
delete m_action;
}

OPTION & OPTION::operator=(const OPTION & rhs)
{
m_shortName = rhs.m_shortName;
m_longName = rhs.m_longName;
m_action = rhs.m_action->Clone();
m_description = rhs.m_description;
return *this;
}

void OPTION::Help(size_t level) const
{
if (!m_action)
    throw ERROR("Option is not defined.");
std::string indent(level, '\t');
std::cout << indent;
if (!m_shortName.empty())
    std::cout << "-" << m_shortName << ", ";
std::cout << "--" << m_longName << " " << m_action->ParamDescription()
          << "\t" << m_description << m_action->DefaultDescription() << "\n";
m_action->Suboptions().Help(level);
}

bool OPTION::Check(const char * arg) const
{
if (arg == NULL)
    return false;

if (*arg++ != '-')
    return false;

if (*arg == '-')
{
    return m_longName == arg + 1;
}

return m_shortName == arg;
}

PARSER_STATE OPTION::Parse(int argc, char ** argv, void * data)
{
if (!m_action)
    throw ERROR("Option is not defined.");
try
    {
    return m_action->Parse(argc, argv, data);
    }
catch (const ACTION::ERROR & ex)
    {
    if (m_longName.empty())
        throw ERROR("-" + m_shortName + ": " + ex.what());
    else
        throw m_shortName.empty() ? ERROR("--" + m_longName + ": " + ex.what())
                                  : ERROR("--" + m_longName + ", -" + m_shortName + ": " + ex.what());
    }
}

void OPTION::ParseValue(const std::string & value)
{
if (!m_action)
    throw ERROR("Option is not defined.");
try
    {
    return m_action->ParseValue(value);
    }
catch (const ACTION::ERROR & ex)
    {
    throw ERROR(m_longName + ": " + ex.what());
    }
}

OPTION_BLOCK & OPTION_BLOCK::Add(const std::string & shortName,
                                 const std::string & longName,
                                 ACTION * action,
                                 const std::string & description)
{
m_options.push_back(OPTION(shortName, longName, action, description));
return *this;
}

OPTION_BLOCK & OPTION_BLOCK::Add(const std::string & longName,
                                 ACTION * action,
                                 const std::string & description)
{
m_options.push_back(OPTION(longName, action, description));
return *this;
}

void OPTION_BLOCK::Help(size_t level) const
{
if (m_options.empty())
    return;
if (!m_description.empty())
    std::cout << m_description << ":\n";
std::for_each(m_options.begin(),
              m_options.end(),
              [&level](const auto& opt){ opt.Help(level + 1); });
}

PARSER_STATE OPTION_BLOCK::Parse(int argc, char ** argv, void * data)
{
PARSER_STATE state(false, argc, argv);
if (state.argc == 0)
    return state;
while (state.argc > 0 && !state.stop)
    {
    const auto it = std::find_if(m_options.begin(), m_options.end(), [&state](const auto& opt){ return opt.Check(*state.argv); });
    if (it != m_options.end())
        state = it->Parse(--state.argc, ++state.argv, data);
    else
        break;
    }
return state;
}

void OPTION_BLOCK::ParseFile(const std::string & filePath)
{
if (access(filePath.c_str(), R_OK))
    throw ERROR("File '" + filePath + "' does not exists.");
ReadConfigFile(filePath, &OPTION_BLOCK::OptionCallback, this);
}

void OPTION_BLOCK::OptionCallback(const std::string & key, const std::string & value)
{
for (std::vector<OPTION>::iterator it = m_options.begin(); it != m_options.end(); ++it)
    if (it->Name() == key)
        it->ParseValue(value);
}

void OPTION_BLOCKS::Help(size_t level) const
{
std::list<OPTION_BLOCK>::const_iterator it(m_blocks.begin());
while (it != m_blocks.end())
    {
    it->Help(level);
    std::cout << "\n";
    ++it;
    }
}

PARSER_STATE OPTION_BLOCKS::Parse(int argc, char ** argv)
{
PARSER_STATE state(false, argc, argv);
std::list<OPTION_BLOCK>::iterator it(m_blocks.begin());
while (state.argc > 0 && !state.stop && it != m_blocks.end())
    {
    state = it->Parse(state.argc, state.argv);
    ++it;
    }
return state;
}