/***************************************************************************
 *   Copyright (c) 2006 Werner Mayer <wmayer[at]users.sourceforge.net>     *
 *                                                                         *
 *   This file is part of the FreeCAD CAx development system.              *
 *                                                                         *
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU Library General Public           *
 *   License as published by the Free Software Foundation; either          *
 *   version 2 of the License, or (at your option) any later version.      *
 *                                                                         *
 *   This library  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 Library General Public License for more details.                  *
 *                                                                         *
 *   You should have received a copy of the GNU Library General Public     *
 *   License along with this library; see the file COPYING.LIB. If not,    *
 *   write to the Free Software Foundation, Inc., 59 Temple Place,         *
 *   Suite 330, Boston, MA  02111-1307, USA                                *
 *                                                                         *
 ***************************************************************************/


#include "PreCompiled.h"

#include <Base/Tools.h>

#include "Document.h"
#include "GeoFeatureGroupExtension.h"
#include "GroupExtensionPy.h"


using namespace App;
namespace sp = std::placeholders;

EXTENSION_PROPERTY_SOURCE(App::GroupExtension, App::DocumentObjectExtension)

namespace App {
EXTENSION_PROPERTY_SOURCE_TEMPLATE(App::GroupExtensionPython, App::GroupExtension)

// explicit template instantiation
template class AppExport ExtensionPythonT<GroupExtensionPythonT<GroupExtension>>;
}

GroupExtension::GroupExtension()
{
    initExtensionType(GroupExtension::getExtensionClassTypeId());
    
    EXTENSION_ADD_PROPERTY_TYPE(Group,(nullptr),"Base",(App::PropertyType)(Prop_None),"List of referenced objects");

    EXTENSION_ADD_PROPERTY_TYPE(_GroupTouched, (false), "Base", 
            PropertyType(Prop_Hidden|Prop_Transient),0);
}

GroupExtension::~GroupExtension() = default;

DocumentObject* GroupExtension::addObject(const char* sType, const char* pObjectName)
{
    DocumentObject* obj = getExtendedObject()->getDocument()->addObject(sType, pObjectName);
    if(!allowObject(obj)) {
        getExtendedObject()->getDocument()->removeObject(obj->getNameInDocument());
        return nullptr;
    }
    addObject(obj);
    return obj;
}

std::vector<DocumentObject*> GroupExtension::addObject(DocumentObject* obj)
{
    std::vector<DocumentObject*> vec = {obj};
    return addObjects(vec);
}

std::vector< DocumentObject* > GroupExtension::addObjects(std::vector< DocumentObject* > objs) {
    
    std::vector<DocumentObject*> added;
    std::vector<DocumentObject*> grp = Group.getValues();
    for(auto obj : objs) {
            
        if(!allowObject(obj))
            continue;
        
        if (hasObject(obj))
            continue;
            
        //only one group per object. Note that it is allowed to be in a group and geofeaturegroup. However,
        //getGroupOfObject() returns only normal groups, no GeoFeatureGroups. Hence this works.
        auto *group = App::GroupExtension::getGroupOfObject(obj);
        if(group && group != getExtendedObject())
            group->getExtensionByType<App::GroupExtension>()->removeObject(obj);
        
        //if we are in a geofeaturegroup we need to ensure the object is too
        auto geogrp = GeoFeatureGroupExtension::getGroupOfObject(getExtendedObject());
        auto objgrp = GeoFeatureGroupExtension::getGroupOfObject(obj);
        if( geogrp != objgrp ) {
            //what to do depends on if we are in  geofeature group or not
            if(geogrp)
                geogrp->getExtensionByType<GeoFeatureGroupExtension>()->addObject(obj);
            else 
                objgrp->getExtensionByType<GeoFeatureGroupExtension>()->removeObject(obj);
        }
        
        grp.push_back(obj);
        added.push_back(obj);
    }
    
    Group.setValues(grp);
    
    return added;
}

std::vector< DocumentObject* > GroupExtension::setObjects(std::vector< DocumentObject* > obj) {

    Group.setValues(std::vector< DocumentObject* > ());
    return addObjects(obj);
}

std::vector<DocumentObject*> GroupExtension::removeObject(DocumentObject* obj)
{
    std::vector<DocumentObject*> vec = {obj};
    return removeObjects(vec);
}

std::vector< DocumentObject* > GroupExtension::removeObjects(std::vector< DocumentObject* > objs) {

    const std::vector<DocumentObject*> & grp = Group.getValues();
    std::vector<DocumentObject*> newGrp = grp;
    std::vector<DocumentObject*> removed;

    std::vector<DocumentObject*>::iterator end = newGrp.end();
    for(auto obj : objs) {       
       auto res = std::remove(newGrp.begin(), end, obj);
       if(res != end) {
           end = res;
           removed.push_back(obj);
       }
    }
    
    newGrp.erase(end, newGrp.end());
    if (grp.size() != newGrp.size()) {
        Group.setValues (newGrp);
    }
    
    return removed;
}

void GroupExtension::removeObjectsFromDocument()
{
    while (Group.getSize() > 0) {
        // Remove the objects step by step because it can happen
        // that an object is part of several groups and thus a
        // double destruction could be possible
        const std::vector<DocumentObject*> & grp = Group.getValues();
        removeObjectFromDocument(grp.front());
    }
}

void GroupExtension::removeObjectFromDocument(DocumentObject* obj)
{
    // check that object is not invalid
    if (!obj || !obj->getNameInDocument())
        return;

    // remove all children
    if (obj->hasExtension(GroupExtension::getExtensionClassTypeId())) {
        GroupExtension *grp = static_cast<GroupExtension*>(obj->getExtension(GroupExtension::getExtensionClassTypeId()));

        // recursive call to remove all subgroups
        grp->removeObjectsFromDocument();
    }

    getExtendedObject()->getDocument()->removeObject(obj->getNameInDocument());
}

DocumentObject *GroupExtension::getObject(const char *Name) const
{
    DocumentObject* obj = getExtendedObject()->getDocument()->getObject(Name);
    if (obj && hasObject(obj))
        return obj;
    return nullptr;
}

bool GroupExtension::hasObject(const DocumentObject* obj, bool recursive) const
{
    if (obj == getExtendedObject()) {
        return false;
    }

    try {
        const std::vector<DocumentObject*>& grp = Group.getValues();
        for (auto child : grp) {

            if (!child)
                continue;

            if (child == obj) {
                return true;
            }
            else if (child == getExtendedObject()) {
                throw Base::RuntimeError("Cyclic dependencies detected: Search cannot be performed");
            }
            else if ( recursive && child->hasExtension(GroupExtension::getExtensionClassTypeId()) ) {
                App::GroupExtension *subGroup = static_cast<App::GroupExtension *> (
                                        child->getExtension(GroupExtension::getExtensionClassTypeId()));
                std::vector<const GroupExtension*> history;
                history.push_back(this);

                if (subGroup->recursiveHasObject (obj, subGroup, history)) {
                    return true;
                }
            }
        }

        return false;
    }
    catch (const Base::RuntimeError& e) {
        e.ReportException();
        return false;
    }
}

bool GroupExtension::recursiveHasObject(const DocumentObject* obj, const GroupExtension* group, 
                                        std::vector< const GroupExtension* > history) const {

    //the purpose is to prevent infinite recursion when groups form a cyclic graph. To do this 
    //we store every group we processed on the current leave of the tree, and if we reach an 
    //already processed group we know that it not really is a tree but a cycle.
    history.push_back(this);

    //we use hasObject with out recursion to allow override in derived classes
    if(group->hasObject(obj, false))
        return true;

    //we checked for the searched object already with hasObject and did not find it, now we need to
    //do the same for all subgroups
    for (auto child : group->Group.getValues()) {

        if(!child)
            continue;

        if ( child->hasExtension(GroupExtension::getExtensionClassTypeId()) ) {

            auto ext = child->getExtensionByType<GroupExtension>();
            
            if (std::find(history.begin(), history.end(), ext) != history.end()) {
                throw Base::RuntimeError("Cyclic dependencies detected: Search cannot be performed");
            }

            if (recursiveHasObject(obj, ext, history)) {
                return true;
            }
        }
    }
    return false;
}

bool GroupExtension::isChildOf(const GroupExtension* group, bool recursive) const
{
    return group->hasObject(getExtendedObject(), recursive);
}

const std::vector<DocumentObject*> &GroupExtension::getObjects() const
{
    return Group.getValues();
}

std::vector<DocumentObject*> GroupExtension::getObjectsOfType(const Base::Type& typeId) const
{
    std::vector<DocumentObject*> type;
    const std::vector<DocumentObject*>& grp = Group.getValues();
    for (std::vector<DocumentObject*>::const_iterator it = grp.begin(); it != grp.end(); ++it) {
        if ( (*it)->getTypeId().isDerivedFrom(typeId))
            type.push_back(*it);
    }

    return type;
}

int GroupExtension::countObjectsOfType(const Base::Type& typeId) const
{
    int type=0;
    const std::vector<DocumentObject*>& grp = Group.getValues();
    for (std::vector<DocumentObject*>::const_iterator it = grp.begin(); it != grp.end(); ++it) {
        if ( (*it)->getTypeId().isDerivedFrom(typeId))
            type++;
    }

    return type;
}

DocumentObject* GroupExtension::getGroupOfObject(const DocumentObject* obj)
{
    //note that we return here only Groups, but nothing derived from it, e.g. no GeoFeatureGroups.
    //That is important as there are clear differences between groups/geofeature groups (e.g. an object
    //can be in only one group, and only one geofeaturegroup, however, it can be in both at the same time)
    for (auto o : obj->getInList()) {
        if (o->hasExtension(App::GroupExtension::getExtensionClassTypeId(), false))
            return o;
        if (o->hasExtension(App::GroupExtensionPython::getExtensionClassTypeId(), false))
            return o;
    }

    return nullptr;
}

PyObject* GroupExtension::getExtensionPyObject() {

    if (ExtensionPythonObject.is(Py::_None())){
        // ref counter is set to 1
        auto grp = new GroupExtensionPy(this);
        ExtensionPythonObject = Py::Object(grp,true);
    }
    return Py::new_reference_to(ExtensionPythonObject);
}

void GroupExtension::extensionOnChanged(const Property* p) {

    //objects are only allowed in a single group. Note that this check must only be done for normal
    //groups, not any derived classes
    if((this->getExtensionTypeId() == GroupExtension::getExtensionClassTypeId())
        && p == &Group && !Group.testStatus(Property::User3)) 
    {
        if(!getExtendedObject()->isRestoring() &&
           !getExtendedObject()->getDocument()->isPerformingTransaction()) {
            
            bool error = false;
            auto corrected = Group.getValues();
            for(auto obj : Group.getValues()) {

                //we have already set the obj into the group, so in a case of multiple groups getGroupOfObject
                //would return anyone of it and hence it is possible that we miss an error. We need a custom check
                auto list = obj->getInList();
                for (auto in : list) {
                    if(in->hasExtension(App::GroupExtension::getExtensionClassTypeId(), false) &&
                        in != getExtendedObject()) {
                        error = true;
                        corrected.erase(std::remove(corrected.begin(), corrected.end(), obj), corrected.end());
                    }
                }
            }

            //if an error was found we need to correct the values and inform the user
            if(error) {
                Base::ObjectStatusLocker<Property::Status, Property> guard(Property::User3, &Group);
                Group.setValues(corrected);
                throw Base::RuntimeError("Object can only be in a single Group");
            }
        }
    }

    if(p == &Group) {
        _Conns.clear();
        for(auto obj : Group.getValue()) {
            if(obj && obj->getNameInDocument()) {
                //NOLINTBEGIN
                _Conns[obj] = obj->signalChanged.connect(std::bind(
                            &GroupExtension::slotChildChanged,this,sp::_1, sp::_2));
                //NOLINTEND
            }
        }
    }

    App::Extension::extensionOnChanged(p);
}

void GroupExtension::slotChildChanged(const DocumentObject &obj, const Property &prop) {
    if(&prop == &obj.Visibility)
        _GroupTouched.touch();
}

bool GroupExtension::extensionGetSubObject(DocumentObject *&ret, const char *subname,
        PyObject **pyObj, Base::Matrix4D *mat, bool /*transform*/, int depth) const 
{
    const char *dot;
    if(!subname || *subname==0) {
        auto obj = Base::freecad_dynamic_cast<const DocumentObject>(getExtendedContainer());
        ret = const_cast<DocumentObject*>(obj);
        return true;
    }
    dot=strchr(subname,'.');
    if(!dot)
        return false;
    if(subname[0]!='$')
        ret = Group.find(std::string(subname,dot));
    else{
        std::string name = std::string(subname+1,dot);
        for(auto child : Group.getValues()) {
            if(name == child->Label.getStrValue()){
                ret = child;
                break;
            }
        }
    }
    if(!ret) 
        return false;
    return ret->getSubObject(dot+1,pyObj,mat,true,depth+1);
}

bool GroupExtension::extensionGetSubObjects(std::vector<std::string> &ret, int) const {
    for(auto obj : Group.getValues()) {
        if(obj && obj->getNameInDocument())
            ret.push_back(std::string(obj->getNameInDocument())+'.');
    }
    return true;
}

App::DocumentObjectExecReturn *GroupExtension::extensionExecute() {
    // This touch property is for propagating changes to upper group
    _GroupTouched.touch();
    return inherited::extensionExecute();
}

std::vector<App::DocumentObject*> GroupExtension::getAllChildren() const {
    std::vector<DocumentObject*> res;
    std::set<DocumentObject*> rset;
    getAllChildren(res,rset);
    return res;
}

void GroupExtension::getAllChildren(std::vector<App::DocumentObject*> &res,
        std::set<App::DocumentObject*> &rset) const
{
    for(auto obj : Group.getValues()) {
        if(!obj || !obj->getNameInDocument())
            continue;
        if(!rset.insert(obj).second)
            continue;
        res.push_back(obj);
        auto ext = obj->getExtensionByType<GroupExtension>(true,false);
        if(ext) 
            ext->getAllChildren(res,rset);
    }
}