/***************************************************************************
 *   Copyright (c) 2017 Ian Rees                  <ian.rees@gmail.com>     *
 *                                                                         *
 *   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"
#ifndef _PreComp_
    #include <algorithm>
    #include <vector>
    #include <boost/algorithm/string/replace.hpp>
#endif  //  #ifndef _PreComp_

#include "Exporter.h"

#include "Core/Iterator.h"

#include "Base/Console.h"
#include "Base/Exception.h"
#include "Base/FileInfo.h"
#include "Base/Sequencer.h"
#include "Base/Stream.h"
#include "Base/Tools.h"

#include "App/Part.h"

#include <zipios++/zipoutputstream.h>

using namespace Mesh;
using namespace MeshCore;

Exporter::Exporter() :
    meshFeatId( Base::Type::fromName("Mesh::Feature") ),
    appPartId( Base::Type::fromName("Part::Feature") ),
    groupExtensionId( App::GroupExtension::getExtensionClassTypeId() )
{ }

//static
std::string Exporter::xmlEscape(const std::string &input)
{
    std::string out(input);
    boost::replace_all(out, "&", "&amp;");
    boost::replace_all(out, "\"", "&quot;");
    boost::replace_all(out, "'", "&apos;");
    boost::replace_all(out, "<", "&lt;");
    boost::replace_all(out, ">", "&gt;");
    return out;
}

bool Exporter::addAppGroup(App::DocumentObject *obj, float tol)
{
    auto ret(true);

    auto groupEx( obj->getExtensionByType<App::GroupExtension>() );
    for (auto it : groupEx->Group.getValues()) {
        if (it->getTypeId().isDerivedFrom(meshFeatId)) {
            ret &= addMeshFeat(it);
        } else if (it->getTypeId().isDerivedFrom(appPartId)) {
            ret &= addPartFeat(it, tol);
        } else if (it->hasExtension(groupExtensionId)) {
            // Recurse
            ret &= addAppGroup(it, tol);
        }
    }

    return ret;
}

bool Exporter::addObject(App::DocumentObject *obj, float tol)
{
    if (obj->getTypeId().isDerivedFrom(meshFeatId)) {
        return addMeshFeat( obj );
    } else if (obj->getTypeId().isDerivedFrom(appPartId)) {
        return addPartFeat( obj, tol );
    } else if (obj->hasExtension(groupExtensionId)) {
        return addAppGroup( obj, tol );
    } else {
        Base::Console().Message(
            "'%s' is of type %s, and can not be exported as a mesh.\n",
            obj->Label.getValue(), obj->getTypeId().getName() );
        return false;
    }
}

MergeExporter::MergeExporter(std::string fileName, MeshIO::Format)
    :fName(fileName)
{
}

MergeExporter::~MergeExporter()
{
    // if we have more than one segment set the 'save' flag
    if (mergingMesh.countSegments() > 1) {
        for (unsigned long i = 0; i < mergingMesh.countSegments(); ++i) {
            mergingMesh.getSegment(i).save(true);
        }
    }

    try {
        mergingMesh.save(fName.c_str());
    }
    catch (const Base::Exception& e) {
        std::cerr << "Saving mesh failed: " << e.what() << std::endl;
    }
}


bool MergeExporter::addMeshFeat(App::DocumentObject *obj)
{
    const MeshObject &mesh( static_cast<Mesh::Feature *>(obj)->Mesh.getValue() );

    MeshCore::MeshKernel kernel( mesh.getKernel() );
    kernel.Transform(mesh.getTransform());

    auto countFacets( mergingMesh.countFacets() );
    if (countFacets == 0) {
        mergingMesh.setKernel(kernel);
    } else {
        mergingMesh.addMesh(kernel);
    }

    // if the mesh already has persistent segments then use them instead
    unsigned long numSegm = mesh.countSegments();
    unsigned long canSave = 0;
    for (unsigned long i=0; i<numSegm; i++) {
        if (mesh.getSegment(i).isSaved())
            canSave++;
    }

    if (canSave > 0) {
        for (unsigned long i=0; i<numSegm; i++) {
            const Segment& segm = mesh.getSegment(i);
            if (segm.isSaved()) {
                std::vector<unsigned long> indices = segm.getIndices();
                std::for_each( indices.begin(), indices.end(),
                               [countFacets] (unsigned long &v) {
                                   v += countFacets;
                               } );
                Segment new_segm(&mergingMesh, indices, true);
                new_segm.setName(segm.getName());
                mergingMesh.addSegment(new_segm);
            }
        }
    } else {
        // now create a segment for the added mesh
        std::vector<unsigned long> indices;
        indices.resize(mergingMesh.countFacets() - countFacets);
        std::generate(indices.begin(), indices.end(), Base::iotaGen<unsigned long>(countFacets));
        Segment segm(&mergingMesh, indices, true);
        segm.setName(obj->Label.getValue());
        mergingMesh.addSegment(segm);
    }

    return true;
}

bool MergeExporter::addPartFeat(App::DocumentObject *obj, float tol)
{
    auto *shape(obj->getPropertyByName("Shape"));
    if (shape && shape->getTypeId().isDerivedFrom(App::PropertyComplexGeoData::getClassTypeId())) {
        Base::Reference<MeshObject> mesh(new MeshObject());

        auto countFacets( mergingMesh.countFacets() );

        auto geoData( static_cast<App::PropertyComplexGeoData*>(shape)->getComplexData() );
        if (geoData) {
            App::GeoFeature* gf = static_cast<App::GeoFeature*>(obj);
            Base::Placement plm = gf->globalPlacement();
            Base::Placement pl  = gf->Placement.getValue();
            Base::Placement plInverse = pl.inverse();
            bool applyGlobal = false;
            if (pl == plm) {
               //no extension placement
               applyGlobal = false;
            } else {
               //there is a placement from extension
               applyGlobal = true;
            }

            std::vector<Base::Vector3d> aPoints;
            std::vector<Data::ComplexGeoData::Facet> aTopo;
            geoData->getFaces(aPoints, aTopo, tol);

            if (applyGlobal) {
                for (auto& it : aPoints) {
                    plInverse.multVec(it,it);
                    plm.multVec(it, it);
                }
            }

            mesh->addFacets(aTopo, aPoints, false);
            if (countFacets == 0)
                mergingMesh = *mesh;
            else
                mergingMesh.addMesh(*mesh);
        } else {
            return false;
        }

        // now create a segment for the added mesh
        std::vector<unsigned long> indices;
        indices.resize(mergingMesh.countFacets() - countFacets);
        std::generate(indices.begin(), indices.end(), Base::iotaGen<unsigned long>(countFacets));
        Segment segm(&mergingMesh, indices, true);
        segm.setName(obj->Label.getValue());
        mergingMesh.addSegment(segm);
        
        return true;
    }
    return false;
}

AmfExporter::AmfExporter( std::string fileName,
                          const std::map<std::string, std::string> &meta,
                          bool compress ) :
    outputStreamPtr(nullptr), nextObjectIndex(0)
{
    // ask for write permission
    Base::FileInfo fi(fileName.c_str());
    Base::FileInfo di(fi.dirPath().c_str());
    if ((fi.exists() && !fi.isWritable()) || !di.exists() || !di.isWritable()) {
        throw Base::FileException("No write permission for file", fileName);
    }

    if (compress) {
        auto *zipStreamPtr( new zipios::ZipOutputStream(fi.filePath()) );

        // ISO 52915 specifies that compressed AMF files are zip-compressed and
        // must contain the AMF XML in an entry with the same name as the
        // compressed file.  It's OK to have other files in the zip too.
        zipStreamPtr->putNextEntry( zipios::ZipCDirEntry(fi.fileName()) );

        // Default compression seems to work fine.
        outputStreamPtr = zipStreamPtr;

    } else {
        outputStreamPtr = new Base::ofstream(fi, std::ios::out | std::ios::binary);
    }

    if (outputStreamPtr) {
        *outputStreamPtr << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
                         << "<amf unit=\"millimeter\">\n";
        for (auto const &metaEntry : meta) {
            *outputStreamPtr << "\t<metadata type=\"" << metaEntry.first
                             << "\">" << metaEntry.second << "</metadata>\n";
        }
    }
}

AmfExporter::~AmfExporter()
{
    if (outputStreamPtr) {
        *outputStreamPtr << "\t<constellation id=\"0\">\n";
        for (auto objId(0); objId < nextObjectIndex; ++objId) {
            *outputStreamPtr << "\t\t<instance objectid=\"" << objId << "\">\n"
                             << "\t\t\t<deltax>0</deltax>\n"
                             << "\t\t\t<deltay>0</deltay>\n"
                             << "\t\t\t<rz>0</rz>\n"
                             << "\t\t</instance>\n";
        }
        *outputStreamPtr << "\t</constellation>\n"
                         << "</amf>\n";
        delete outputStreamPtr;
    }
}

bool AmfExporter::addPartFeat(App::DocumentObject *obj, float tol)
{
    auto *shape(obj->getPropertyByName("Shape"));

    if (shape && shape->getTypeId().isDerivedFrom(App::PropertyComplexGeoData::getClassTypeId())) {
        Base::Reference<MeshObject> mesh(new MeshObject());

        auto geoData( static_cast<App::PropertyComplexGeoData*>(shape)->getComplexData() );
        if (geoData) {
            std::vector<Base::Vector3d> aPoints;
            std::vector<Data::ComplexGeoData::Facet> aTopo;
            geoData->getFaces(aPoints, aTopo, tol);

            mesh->addFacets(aTopo, aPoints, false);
        } else {
            return false;
        }

        MeshCore::MeshKernel kernel = mesh->getKernel();
        kernel.Transform(mesh->getTransform());

        std::map<std::string, std::string> meta;
        meta["name"] = xmlEscape(obj->Label.getStrValue());

        return addMesh(kernel, meta);
    }
    return false;
}

bool AmfExporter::addMeshFeat(App::DocumentObject *obj)
{
    const MeshObject &mesh( static_cast<Mesh::Feature *>(obj)->Mesh.getValue() );
    MeshCore::MeshKernel kernel( mesh.getKernel() );
    kernel.Transform(mesh.getTransform());

    std::map<std::string, std::string> meta;
    meta["name"] = xmlEscape(obj->Label.getStrValue());

    return addMesh(kernel, meta);
}

bool AmfExporter::addMesh(const MeshCore::MeshKernel &kernel,
                          const std::map<std::string, std::string> &meta)
{
    if (!outputStreamPtr || outputStreamPtr->bad()) {
        return false;
    }

    auto numFacets( kernel.CountFacets() );

    if (numFacets == 0) {
        return false;
    }

    MeshCore::MeshFacetIterator clIter(kernel), clEnd(kernel);

    Base::SequencerLauncher seq("Saving...", 2 * numFacets + 1);

    *outputStreamPtr << "\t<object id=\"" << nextObjectIndex << "\">\n";

    for (auto const &metaEntry : meta) {
        *outputStreamPtr << "\t\t<metadata type=\"" << metaEntry.first
                         << "\">" << metaEntry.second << "</metadata>\n";
    }
    *outputStreamPtr << "\t\t<mesh>\n"
                     << "\t\t\t<vertices>\n";

    const MeshCore::MeshGeomFacet *facet;

    // Iterate through all facets of the mesh, and construct a:
    //   * Cache (map) of used vertices, outputting each new unique vertex to
    //     the output stream as we find it
    //   * Vector of the vertices, referred to by the indices from 1 
    std::map<Base::Vector3f, unsigned long, AmfExporter::VertLess> vertices;
    auto vertItr(vertices.begin());
    auto vertexCount(0UL);

    // {facet1A, facet1B, facet1C, facet2A, ..., facetNC}
    std::vector<unsigned long> facets;

    // For each facet in mesh
    for(clIter.Begin(), clEnd.End(); clIter < clEnd; ++clIter) {
        facet = &(*clIter);

        // For each vertex in facet
        for (auto i(0); i < 3; ++i) {
            vertItr = vertices.find(facet->_aclPoints[i]);

            if ( vertItr == vertices.end() ) {
                facets.push_back(vertexCount);

                vertices[facet->_aclPoints[i]] = vertexCount++;

                // Output facet
                *outputStreamPtr << "\t\t\t\t<vertex>\n"
                                 << "\t\t\t\t\t<coordinates>\n";
                for ( auto j(0); j < 3; ++j) {
                    char axis('x' + j);
                    *outputStreamPtr << "\t\t\t\t\t\t<" << axis << '>'
                                     << facet->_aclPoints[i][j]
                                     << "</" << axis << ">\n";
                }
                *outputStreamPtr << "\t\t\t\t\t</coordinates>\n"
                                 << "\t\t\t\t</vertex>\n";
            } else {
                facets.push_back(vertItr->second);
            }
        }

        seq.next(true); // allow to cancel
    }

    *outputStreamPtr << "\t\t\t</vertices>\n"
                     << "\t\t\t<volume>\n";
    
    // Now that we've output all the vertices, we can
    // output the facets that refer to them!
    for (auto triItr(facets.begin()); triItr != facets.end(); ) {
        *outputStreamPtr << "\t\t\t\t<triangle>\n";
        for (auto i(1); i < 4; ++i) {
            *outputStreamPtr << "\t\t\t\t\t<v" << i << '>'
                             << *(triItr++) << "</v" << i << ">\n";
        }
        *outputStreamPtr << "\t\t\t\t</triangle>\n";
        seq.next(true); // allow to cancel
    }

    *outputStreamPtr << "\t\t\t</volume>\n"
                     << "\t\t</mesh>\n"
                     << "\t</object>\n";

    ++nextObjectIndex;
    return true;
}