/*
   Copyright (C) 2001-2006, William Joseph.
   All Rights Reserved.

   This file is part of GtkRadiant.

   GtkRadiant 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.

   GtkRadiant 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 GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#if !defined( INCLUDED_PREFERENCEDICTIONARY_H )
#define INCLUDED_PREFERENCEDICTIONARY_H

#include "preferencesystem.h"
#include "xml/ixml.h"
#include "stream/stringstream.h"
#include "generic/callback.h"
#include "versionlib.h"
#include <map>

class PreferenceDictionary : public PreferenceSystem {
    class PreferenceEntry {
        Property<const char *> m_cb;
    public:
        PreferenceEntry(const Property<const char *> &cb)
                : m_cb(cb)
        {
        }

        void importString(const char *string)
        {
            m_cb.set(string);
        }

        void exportString(const Callback<void(const char *)> &importer)
        {
            m_cb.get(importer);
        }
    };

    typedef std::map<CopiedString, PreferenceEntry> PreferenceEntries;
    PreferenceEntries m_preferences;

    typedef std::map<CopiedString, CopiedString> PreferenceCache;
    PreferenceCache m_cache;

public:
    typedef PreferenceEntries::iterator iterator;

    iterator begin()
    {
        return m_preferences.begin();
    }

    iterator end()
    {
        return m_preferences.end();
    }

    iterator find(const char *name)
    {
        return m_preferences.find(name);
    }

    void registerPreference(const char *name, const Property<const char *> &cb)
    {
        m_preferences.insert(PreferenceEntries::value_type(name, PreferenceEntry(cb)));
        PreferenceCache::iterator i = m_cache.find(name);
        if (i != m_cache.end()) {
            cb.set(i->second.c_str());
            m_cache.erase(i);
        }
    }

    void importPref(const char *name, const char *value)
    {
        PreferenceEntries::iterator i = m_preferences.find(name);
        if (i != m_preferences.end()) {
            (*i).second.importString(value);
        } else {
            m_cache.erase(name);
            m_cache.insert(PreferenceCache::value_type(name, value));
        }
    }
};

inline void XMLPreference_importString(XMLImporter &importer, const char *value)
{
    importer.write(value, string_length(value));
}

typedef ReferenceCaller<XMLImporter, void(const char *), XMLPreference_importString> XMLPreferenceImportStringCaller;

class XMLPreferenceDictionaryExporter : public XMLExporter {
    class XMLQPrefElement : public XMLElement {
        const char *m_version;
    public:
        XMLQPrefElement(const char *version) : m_version(version)
        {
        }

        const char *name() const
        {
            return "qpref";
        }

        const char *attribute(const char *name) const
        {
            if (string_equal(name, "version")) {
                return m_version;
            }
            return "";
        }

        void forEachAttribute(XMLAttrVisitor &visitor) const
        {
            visitor.visit("version", m_version);
        }
    };

    class XMLPreferenceElement : public XMLElement {
        const char *m_name;
    public:
        XMLPreferenceElement(const char *name)
                : m_name(name)
        {
        }

        const char *name() const
        {
            return "epair";
        }

        const char *attribute(const char *name) const
        {
            if (string_equal(name, "name")) {
                return m_name;
            }
            return "";
        }

        void forEachAttribute(XMLAttrVisitor &visitor) const
        {
            visitor.visit("name", m_name);
        }
    };

    typedef PreferenceDictionary PreferenceEntries;
    PreferenceEntries &m_preferences;
    const char *m_version;
public:
    XMLPreferenceDictionaryExporter(PreferenceDictionary &preferences, const char *version)
            : m_preferences(preferences), m_version(version)
    {
    }

    void exportXML(XMLImporter &importer)
    {
        importer.write("\n", 1);

        XMLQPrefElement qpref_element(m_version);
        importer.pushElement(qpref_element);
        importer.write("\n", 1);

        for (PreferenceEntries::iterator i = m_preferences.begin(); i != m_preferences.end(); ++i) {
            XMLPreferenceElement epair_element((*i).first.c_str());

            importer.pushElement(epair_element);

            (*i).second.exportString(XMLPreferenceImportStringCaller(importer));

            importer.popElement(epair_element.name());
            importer.write("\n", 1);
        }

        importer.popElement(qpref_element.name());
        importer.write("\n", 1);
    }
};

class XMLPreferenceDictionaryImporter : public XMLImporter {
    struct xml_state_t {
        enum ETag {
            tag_qpref,
            tag_qpref_ignore,
            tag_epair,
            tag_epair_ignore
        };

        xml_state_t(ETag tag)
                : m_tag(tag)
        {
        }

        ETag m_tag;
        CopiedString m_name;
        StringOutputStream m_ostream;
    };

    typedef std::vector<xml_state_t> xml_stack_t;
    xml_stack_t m_xml_stack;

    typedef PreferenceDictionary PreferenceEntries;
    PreferenceEntries &m_preferences;
    Version m_version;
public:
    XMLPreferenceDictionaryImporter(PreferenceDictionary &preferences, const char *version)
            : m_preferences(preferences), m_version(version_parse(version))
    {
    }

    void pushElement(const XMLElement &element)
    {
        if (m_xml_stack.empty()) {
            if (string_equal(element.name(), "qpref")) {
                Version dataVersion(version_parse(element.attribute("version")));
                if (!version_compatible(m_version, dataVersion)) {
                    globalOutputStream() << "qpref import: data version " << dataVersion
                                         << " is not compatible with code version " << m_version << "\n";
                    m_xml_stack.push_back(xml_state_t::tag_qpref_ignore);
                } else {
                    globalOutputStream() << "qpref import: data version " << dataVersion
                                         << " is compatible with code version " << m_version << "\n";
                    m_xml_stack.push_back(xml_state_t::tag_qpref);
                }
            } else {
                // not valid
            }
        } else {
            switch (m_xml_stack.back().m_tag) {
                case xml_state_t::tag_qpref:
                    if (string_equal(element.name(), "epair")) {
                        m_xml_stack.push_back(xml_state_t::tag_epair);
                        m_xml_stack.back().m_name = element.attribute("name");
                    } else {
                        // not valid
                    }
                    break;
                case xml_state_t::tag_qpref_ignore:
                    if (string_equal(element.name(), "epair")) {
                        m_xml_stack.push_back(xml_state_t::tag_epair_ignore);
                    } else {
                        // not valid
                    }
                    break;
                case xml_state_t::tag_epair:
                case xml_state_t::tag_epair_ignore:
                    // not valid
                    break;
            }
        }

    }

    void popElement(const char *name)
    {
        if (m_xml_stack.back().m_tag == xml_state_t::tag_epair) {
            m_preferences.importPref(m_xml_stack.back().m_name.c_str(), m_xml_stack.back().m_ostream.c_str());
        }
        m_xml_stack.pop_back();
    }

    std::size_t write(const char *buffer, std::size_t length)
    {
        return m_xml_stack.back().m_ostream.write(buffer, length);
    }
};

#endif