#include "hecl/CVarManager.hpp"
#include "hecl/Console.hpp"
#include <athena/FileWriter.hpp>
#include <athena/Utility.hpp>
#include <hecl/Runtime.hpp>
#include <hecl/hecl.hpp>
#include <memory>
#include <regex>

namespace hecl
{

CVar* com_developer = nullptr;
CVar* com_configfile = nullptr;
CVar* com_enableCheats = nullptr;

static const std::regex cmdLineRegex("\\+([\\w\\.]+)=([\\w\\.\\-]+)");
CVarManager* CVarManager::m_instance = nullptr;

static logvisor::Module CVarLog("CVarManager");
CVarManager::CVarManager(hecl::Runtime::FileStoreManager& store, bool useBinary)
    : m_store(store),
      m_useBinary(useBinary)
{
    m_instance = this;
    com_configfile = newCVar("config", "File to store configuration", std::string("config"), CVar::EFlags::System);
    com_developer = newCVar("developer", "Enables developer mode", false, (CVar::EFlags::System | CVar::EFlags::ReadOnly | CVar::EFlags::InternalArchivable));
    com_enableCheats = newCVar("cheats", "Enable cheats", false, (CVar::EFlags::System | CVar::EFlags::ReadOnly | CVar::EFlags::Hidden));
}

CVarManager::~CVarManager()
{
}

CVar* CVarManager::registerCVar(std::unique_ptr<CVar>&& cvar)
{
    std::string tmp(cvar->name());
    athena::utility::tolower(tmp);
    if (m_cvars.find(tmp) != m_cvars.end())
        return nullptr;

    CVar* ret = cvar.get();
    m_cvars[tmp] = std::move(cvar);
    return ret;
}

CVar* CVarManager::findCVar(std::string_view name)
{
    std::string lower(name);
    athena::utility::tolower(lower);
    auto search = m_cvars.find(lower);
    if (search == m_cvars.end())
        return nullptr;

    return search->second.get();
}

std::vector<CVar*> CVarManager::archivedCVars() const
{
    std::vector<CVar*> ret;
    for (const auto& pair : m_cvars)
        if (pair.second->isArchive())
            ret.push_back(pair.second.get());

    return ret;
}

std::vector<CVar*> CVarManager::cvars(CVar::EFlags filter) const
{
    std::vector<CVar*> ret;
    for (const auto& pair : m_cvars)
        if (filter == CVar::EFlags::None || (pair.second->flags() & filter) != 0)
            ret.push_back(pair.second.get());

    return ret;
}

void CVarManager::deserialize(CVar* cvar)
{
    if (!cvar)
        return;

    /* First let's check for a deferred value */
    std::string lowName = cvar->name().data();
    athena::utility::tolower(lowName);
    if (m_deferedCVars.find(lowName) != m_deferedCVars.end())
    {
        std::string val = m_deferedCVars[lowName];
        m_deferedCVars.erase(lowName);
        if (cvar->fromLiteralToType(val))
            return;
    }

    /* We were either unable to find a deferred value or got an invalid value */
    if (!cvar->isArchive() && !cvar->isInternalArchivable())
        return;

#if _WIN32
    hecl::SystemString filename = hecl::SystemString(m_store.getStoreRoot()) + _SYS_STR('/') + com_configfile->toWideLiteral();
#else
    hecl::SystemString filename = hecl::SystemString(m_store.getStoreRoot()) + _SYS_STR('/') + com_configfile->toLiteral();
#endif
    hecl::Sstat st;

    if (m_useBinary)
    {
        CVarContainer container;
        filename += _SYS_STR(".bin");
        if (hecl::Stat(filename.c_str(), &st) || !S_ISREG(st.st_mode))
            return;
        athena::io::FileReader reader(filename);
        if (reader.isOpen())
            container.read(reader);

        if (container.cvars.size() > 0)
        {
            auto serialized = std::find_if(container.cvars.begin(),
                                           container.cvars.end(),
            [&cvar](const DNACVAR::CVar& c) { return c.m_name == cvar->name(); });

            if (serialized != container.cvars.end())
            {
                DNACVAR::CVar& tmp = *serialized;

                if (cvar->m_value != tmp.m_value)
                {
                    cvar->unlock();
                    cvar->fromLiteralToType(tmp.m_value, true);
                    cvar->m_wasDeserialized = true;
                    cvar->lock();
                }
            }
        }
    }
    else
    {
        filename += _SYS_STR(".yaml");
        if (hecl::Stat(filename.c_str(), &st) || !S_ISREG(st.st_mode))
            return;
        athena::io::FileReader reader(filename);
        if (reader.isOpen())
        {
            athena::io::YAMLDocReader docReader;
            if (docReader.parse(&reader))
            {
                std::unique_ptr<athena::io::YAMLNode> root = docReader.releaseRootNode();
                auto serialized = std::find_if(root->m_mapChildren.begin(),
                                               root->m_mapChildren.end(),
                [&cvar](const auto& c) { return c.first == cvar->name(); });

                if (serialized != root->m_mapChildren.end())
                {
                    const std::unique_ptr<athena::io::YAMLNode>& tmp = serialized->second;

                    if (cvar->m_value != tmp->m_scalarString)
                    {
                        cvar->unlock();
                        cvar->fromLiteralToType(tmp->m_scalarString, true);
                        cvar->m_wasDeserialized = true;
                        cvar->lock();
                    }
                }
            }
        }
    }
}

void CVarManager::serialize()
{
#if _WIN32
    hecl::SystemString filename = hecl::SystemString(m_store.getStoreRoot()) + _SYS_STR('/') + com_configfile->toWideLiteral();
#else
    hecl::SystemString filename = hecl::SystemString(m_store.getStoreRoot()) + _SYS_STR('/') + com_configfile->toLiteral();
#endif

    if (m_useBinary)
    {
        CVarContainer container;
        for (const auto& pair : m_cvars)
            if (pair.second->isArchive() || (pair.second->isInternalArchivable() &&
                pair.second->wasDeserialized() && !pair.second->hasDefaultValue()))
                container.cvars.push_back(*pair.second);
        container.cvarCount = atUint32(container.cvars.size());

        filename += _SYS_STR(".bin");
        athena::io::FileWriter writer(filename);
        if (writer.isOpen())
            container.write(writer);
    }
    else
    {
        filename += _SYS_STR(".yaml");

        athena::io::FileReader r(filename);
        athena::io::YAMLDocWriter docWriter(nullptr, r.isOpen() ? &r : nullptr);
        r.close();

        docWriter.setStyle(athena::io::YAMLNodeStyle::Block);
        for (const auto& pair : m_cvars)
            if (pair.second->isArchive() || (pair.second->isInternalArchivable() &&
                pair.second->wasDeserialized() && !pair.second->hasDefaultValue()))
                docWriter.writeString(pair.second->name().data(), pair.second->toLiteral());

        athena::io::FileWriter w(filename);
        if (w.isOpen())
            docWriter.finish(&w);
    }
}

CVarManager* CVarManager::instance()
{
    return m_instance;
}

void CVarManager::list(Console* con, const std::vector<std::string>& /*args*/)
{
    for (const auto& cvar : m_cvars)
    {
        if (!cvar.second->isHidden())
            con->report(Console::Level::Info, "%s: %s", cvar.second->name().data(), cvar.second->help().c_str());
    }
}

void CVarManager::setCVar(Console* con, const std::vector<std::string> &args)
{
    if (args.size() < 2)
    {
        con->report(Console::Level::Info, "Usage setCvar <cvar> <value>");
        return;
    }

    std::string cvName = args[0];
    athena::utility::tolower(cvName);
    if (m_cvars.find(cvName) == m_cvars.end())
    {
        con->report(Console::Level::Error, "CVar '%s' does not exist", args[0].c_str());
        return;
    }

    const auto& cv = m_cvars[cvName];
    std::string oldVal = cv->value();
    std::string value = args[1];
    auto it = args.begin() + 2;
    for (; it != args.end(); ++it)
        value += " " + *it;

    /*  Check to make sure we're not redundantly assigning the value */
    if (cv->value() == value)
        return;

    if (!cv->fromLiteralToType(value))
        con->report(Console::Level::Warning, "Unable to set cvar '%s' to value '%s'", cv->name().data(), value.c_str());
    else
        con->report(Console::Level::Info, "Set '%s' from '%s' to '%s'", cv->name().data(), oldVal.c_str(), value.c_str());
}

void CVarManager::getCVar(Console* con, const std::vector<std::string> &args)
{
    if (args.empty())
    {
        con->report(Console::Level::Info, "Usage getCVar <cvar>");
        return;
    }

    std::string cvName = args[0];
    athena::utility::tolower(cvName);
    if (m_cvars.find(cvName) == m_cvars.end())
    {
        con->report(Console::Level::Error, "CVar '%s' does not exist", args[0].c_str());
        return;
    }

    const auto& cv = m_cvars[cvName];
    con->report(Console::Level::Info, "'%s' = '%s'", cv->name().data(), cv->value().c_str());
}

void CVarManager::setDeveloperMode(bool v, bool setDeserialized)
{
    com_developer->unlock();
    com_developer->fromBoolean(v);
    if (setDeserialized)
        com_developer->m_wasDeserialized = true;
    com_developer->lock();
    com_developer->setModified();

}

bool CVarManager::restartRequired() const
{
    for (const auto& cv : m_cvars)
    {
        if (cv.second->isModified() && cv.second->modificationRequiresRestart())
            return true;
    }

    return false;
}

void CVarManager::parseCommandLine(const std::vector<SystemString>& args)
{
    bool oldDeveloper = suppressDeveloper();
    std::string developerName = com_developer->name().data();
    athena::utility::tolower(developerName);
    for (const SystemString& arg : args)
    {
        if (arg[0] == _SYS_STR('+'))
        {
            std::string tmp = SystemUTF8Conv(arg).c_str();

            std::smatch matches;
            if (std::regex_match(tmp, matches, cmdLineRegex))
            {
                std::string cvarName = matches[1].str();
                std::string cvarValue = matches[2].str();
                if (CVar* cv = findCVar(cvarName))
                {
                    cv->fromLiteralToType(cvarValue);
                    athena::utility::tolower(cvarName);
                    if (developerName == cvarName)
                        /* Make sure we're not overriding developer mode when we restore */
                        oldDeveloper = com_developer->toBoolean();
                }
                else
                {
                    /* Unable to find an existing CVar, let's defer for the time being 8 */
                    athena::utility::tolower(cvarName);
                    m_deferedCVars[cvarName] = cvarValue;
                }
            }
        }
    }

    restoreDeveloper(oldDeveloper);
}

bool CVarManager::suppressDeveloper()
{
    bool oldDeveloper = com_developer->toBoolean();
    CVarUnlocker unlock(com_developer);
    com_developer->fromBoolean(true);

    return oldDeveloper;
}

void CVarManager::restoreDeveloper(bool oldDeveloper)
{
    CVarUnlocker unlock(com_developer);
    com_developer->fromBoolean(oldDeveloper);
}

}