/*
Copyright (C) 2012 Sebastian Herbord. All rights reserved.

This file is part of Mod Organizer.

Mod Organizer 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.

Mod Organizer 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 Mod Organizer.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "executableslist.h"

#include "iplugingame.h"
#include "utility.h"
#include <log.h>

#include <QFileInfo>
#include <QDir>
#include <QDebug>
#include <QCoreApplication>


#include <algorithm>


using namespace MOBase;

ExecutablesList::iterator ExecutablesList::begin()
{
  return m_Executables.begin();
}

ExecutablesList::const_iterator ExecutablesList::begin() const
{
  return m_Executables.begin();
}

ExecutablesList::iterator ExecutablesList::end()
{
  return m_Executables.end();
}

ExecutablesList::const_iterator ExecutablesList::end() const
{
  return m_Executables.end();
}

std::size_t ExecutablesList::size() const
{
  return m_Executables.size();
}

bool ExecutablesList::empty() const
{
  return m_Executables.empty();
}

void ExecutablesList::load(const MOBase::IPluginGame* game, QSettings& settings)
{
  log::debug("loading executables");

  m_Executables.clear();

  // whether the executable list in the .ini is still using the old custom
  // executables from 2.2.0, see upgradeFromCustom()
  bool needsUpgrade = false;

  int numCustomExecutables = settings.beginReadArray("customExecutables");
  for (int i = 0; i < numCustomExecutables; ++i) {
    settings.setArrayIndex(i);

    Executable::Flags flags;
    if (settings.value("toolbar", false).toBool())
      flags |= Executable::ShowInToolbar;
    if (settings.value("ownicon", false).toBool())
      flags |= Executable::UseApplicationIcon;

    if (settings.contains("custom")) {
      // the "custom" setting only exists in older versions
      needsUpgrade = true;
    }

    setExecutable(Executable()
      .title(settings.value("title").toString())
      .binaryInfo(settings.value("binary").toString())
      .arguments(settings.value("arguments").toString())
      .steamAppID(settings.value("steamAppID", "").toString())
      .workingDirectory(settings.value("workingDirectory", "").toString())
      .flags(flags));
  }

  settings.endArray();

  addFromPlugin(game, IgnoreExisting);

  if (needsUpgrade)
    upgradeFromCustom(game);

  dump();
}

void ExecutablesList::store(QSettings& settings)
{
  settings.remove("customExecutables");
  settings.beginWriteArray("customExecutables");

  int count = 0;

  for (const auto& item : *this) {
    settings.setArrayIndex(count++);

    settings.setValue("title", item.title());
    settings.setValue("toolbar", item.isShownOnToolbar());
    settings.setValue("ownicon", item.usesOwnIcon());
    settings.setValue("binary", item.binaryInfo().absoluteFilePath());
    settings.setValue("arguments", item.arguments());
    settings.setValue("workingDirectory", item.workingDirectory());
    settings.setValue("steamAppID", item.steamAppID());
  }

  settings.endArray();
}

std::vector<Executable> ExecutablesList::getPluginExecutables(
  MOBase::IPluginGame const *game) const
{
  Q_ASSERT(game != nullptr);

  std::vector<Executable> v;

  for (const ExecutableInfo &info : game->executables()) {
    if (!info.isValid()) {
      continue;
    }

    v.push_back({info, Executable::UseApplicationIcon});
  }

  const QFileInfo eppBin(QCoreApplication::applicationDirPath() + "/explorer++/Explorer++.exe");

  if (eppBin.exists()) {
    const auto args = QString("\"%1\"")
      .arg(QDir::toNativeSeparators(game->dataDirectory().absolutePath()));

    const auto exe = Executable()
      .title("Explore Virtual Folder")
      .binaryInfo(eppBin)
      .arguments(args)
      .workingDirectory(eppBin.absolutePath())
      .flags(Executable::UseApplicationIcon);

    v.push_back(exe);
  }

  return v;
}

void ExecutablesList::resetFromPlugin(MOBase::IPluginGame const *game)
{
  log::debug("resetting plugin executables");

  Q_ASSERT(game != nullptr);

  for (const auto& exe : getPluginExecutables(game)) {
    setExecutable(exe, MoveExisting);
  }
}

void ExecutablesList::addFromPlugin(IPluginGame const *game, SetFlags flags)
{
  Q_ASSERT(game != nullptr);

  for (const auto& exe : getPluginExecutables(game)) {
    setExecutable(exe, flags);
  }
}

const Executable &ExecutablesList::get(const QString &title) const
{
  for (const auto& exe : m_Executables) {
    if (exe.title() == title) {
      return exe;
    }
  }

  throw std::runtime_error(QString("executable not found: %1").arg(title).toLocal8Bit().constData());
}

Executable &ExecutablesList::get(const QString &title)
{
  return const_cast<Executable&>(std::as_const(*this).get(title));
}

Executable &ExecutablesList::getByBinary(const QFileInfo &info)
{
  for (Executable &exe : m_Executables) {
    if (exe.binaryInfo() == info) {
      return exe;
    }
  }
  throw std::runtime_error("invalid info");
}

ExecutablesList::iterator ExecutablesList::find(const QString &title)
{
  return std::find_if(begin(), end(), [&](auto&& e) { return e.title() == title; });
}

ExecutablesList::const_iterator ExecutablesList::find(const QString &title) const
{
  return std::find_if(begin(), end(), [&](auto&& e) { return e.title() == title; });
}

bool ExecutablesList::titleExists(const QString &title) const
{
  auto test = [&] (const Executable &exe) { return exe.title() == title; };
  return std::find_if(m_Executables.begin(), m_Executables.end(), test) != m_Executables.end();
}

void ExecutablesList::setExecutable(const Executable &exe)
{
  setExecutable(exe, MergeExisting);
}

void ExecutablesList::setExecutable(const Executable &exe, SetFlags flags)
{
  auto itor = find(exe.title());

  if (itor != end()) {
    if (flags == IgnoreExisting) {
      return;
    }

    if (flags == MoveExisting) {
      const auto newTitle = makeNonConflictingTitle(exe.title());
      if (!newTitle) {
        log::error(
          "executable '{}' was in the way but could not be renamed",
          exe.title());

        return;
      }

      log::warn(
        "executable '{}' was in the way and was renamed to '{}'",
        itor->title(), *newTitle);

      itor->title(*newTitle);
      itor = end();
    }
  }

  if (itor == m_Executables.end()) {
    m_Executables.push_back(exe);
  } else {
    itor->mergeFrom(exe);
  }
}

void ExecutablesList::remove(const QString &title)
{
  auto itor = find(title);
  if (itor != m_Executables.end()) {
    m_Executables.erase(itor);
  }
}

std::optional<QString> ExecutablesList::makeNonConflictingTitle(
  const QString& prefix)
{
  const int max = 100;

  QString title = prefix;

  for (int i=1; i<max; ++i) {
    if (!titleExists(title)) {
      return title;
    }

    title = prefix + QString(" (%1)").arg(i);
  }

  log::error("ran out of executable titles for prefix '{}'", prefix);
  return {};
}

void ExecutablesList::upgradeFromCustom(MOBase::IPluginGame const *game)
{
  log::debug("upgrading executables list");

  Q_ASSERT(game != nullptr);

  // prior to 2.2.1, plugin executables were special in the sense that they
  // did not store certain settings, like the binary info and working directory;
  // those were filled in when MO started, but never saved
  //
  // this interferes with the new executables list, which is completely
  // customizable, because plugin executables are only added to the list when
  // they don't exist at all and are ignored otherwise, leaving some of the
  // fields completely blank
  //
  // when the "custom" setting is found in the .ini file (see load()), it is
  // assumed that the older scheme is still present; in that case, the plugin
  // executables force their binary info and working directory into the existing
  // executables one last time
  //
  // from that point on, plugin executables are ignored unless they're
  // completely missing from the list, allowing users to customize them as they
  // want

  for (const auto& exe : getPluginExecutables(game)) {
    auto itor = find(exe.title());
    if (itor == end()){
      continue;
    }

    if (!itor->binaryInfo().exists()) {
      itor->binaryInfo(exe.binaryInfo());
    }

    if (itor->workingDirectory().isEmpty()) {
      itor->workingDirectory(exe.workingDirectory());
    }
  }
}

void ExecutablesList::dump() const
{
  for (const auto& e : m_Executables) {
    QStringList flags;

    if (e.flags() & Executable::ShowInToolbar) {
      flags.push_back("toolbar");
    }

    if (e.flags() & Executable::UseApplicationIcon) {
      flags.push_back("icon");
    }

    log::debug(
      " . executable '{}'\n"
      "    binary: {}\n"
      "    arguments: {}\n"
      "    steam ID: {}\n"
      "    directory: {}\n"
      "    flags: {} ({})",
      e.title(), e.binaryInfo().absoluteFilePath(), e.arguments(),
      e.steamAppID(), e.workingDirectory(), flags.join("|"), e.flags());
  }
}


Executable::Executable(QString title)
  : m_title(title)
{
}

Executable::Executable(const MOBase::ExecutableInfo& info, Flags flags) :
  m_title(info.title()),
  m_binaryInfo(info.binary()),
  m_arguments(info.arguments().join(" ")),
  m_steamAppID(info.steamAppID()),
  m_workingDirectory(info.workingDirectory().absolutePath()),
  m_flags(flags)
{
}

const QString& Executable::title() const
{
  return m_title;
}

const QFileInfo& Executable::binaryInfo() const
{
  return m_binaryInfo;
}

const QString& Executable::arguments() const
{
  return m_arguments;
}

const QString& Executable::steamAppID() const
{
  return m_steamAppID;
}

const QString& Executable::workingDirectory() const
{
  return m_workingDirectory;
}

Executable::Flags Executable::flags() const
{
  return m_flags;
}

Executable& Executable::title(const QString& s)
{
  m_title = s;
  return *this;
}

Executable& Executable::binaryInfo(const QFileInfo& fi)
{
  m_binaryInfo = fi;
  return *this;
}

Executable& Executable::arguments(const QString& s)
{
  m_arguments = s;
  return *this;
}

Executable& Executable::steamAppID(const QString& s)
{
  m_steamAppID = s;
  return *this;
}

Executable& Executable::workingDirectory(const QString& s)
{
  m_workingDirectory = s;
  return *this;
}

Executable& Executable::flags(Flags f)
{
  m_flags = f;
  return *this;
}

bool Executable::isShownOnToolbar() const
{
  return m_flags.testFlag(ShowInToolbar);
}

void Executable::setShownOnToolbar(bool state)
{
  if (state) {
    m_flags |= ShowInToolbar;
  } else {
    m_flags &= ~ShowInToolbar;
  }
}

bool Executable::usesOwnIcon() const
{
  return m_flags.testFlag(UseApplicationIcon);
}

void Executable::mergeFrom(const Executable& other)
{
  // flags on plugin executables that the user is allowed to change
  const auto allow = ShowInToolbar;

  // this happens after executables are loaded from settings and plugin
  // executables are being added, or when users are modifying executables

  m_title = other.title();
  m_binaryInfo = other.binaryInfo();
  m_arguments = other.arguments();
  m_steamAppID = other.steamAppID();
  m_workingDirectory = other.workingDirectory();
  m_flags = other.flags();
}