#include "export.h"
#include "globaldefs.h"
#include "debugging/debugging.h"
#include "ibrush.h"
#include "iscenegraph.h"
#include "iselection.h"
#include "stream/stringstream.h"
#include "stream/textfilestream.h"

#include <map>

// this is very evil, but right now there is no better way
#include "../../src/brush.h"

// for limNames
const int MAX_MATERIAL_NAME = 20;

/*
    Abstract baseclass for modelexporters
    the class collects all the data which then gets
    exported through the WriteToFile method.
 */
class ExportData {
public:
    ExportData(const std::set<std::string> &ignorelist, collapsemode mode, bool limNames, bool objs);

    virtual ~ExportData(void);

    virtual void BeginBrush(Brush &b);

    virtual void AddBrushFace(Face &f);

    virtual void EndBrush(void);

    virtual bool WriteToFile(const std::string &path, collapsemode mode) const = 0;

protected:

// a group of faces
    class group {
    public:
        std::string name;
        std::list<const Face *> faces;
    };

    std::list<group> groups;

private:

// "textures/common/caulk" -> "caulk"
    void GetShaderNameFromShaderPath(const char *path, std::string &name);

    group *current;
    collapsemode mode;
    const std::set<std::string> &ignorelist;
};

ExportData::ExportData(const std::set<std::string> &_ignorelist, collapsemode _mode, bool _limNames, bool _objs)
        : mode(_mode),
          ignorelist(_ignorelist)
{
    current = 0;

    // in this mode, we need just one group
    if (mode == COLLAPSE_ALL) {
        groups.push_back(group());
        current = &groups.back();
        current->name = "all";
    }
}

ExportData::~ExportData(void)
{

}

void ExportData::BeginBrush(Brush &b)
{
    // create a new group for each brush
    if (mode == COLLAPSE_NONE) {
        groups.push_back(group());
        current = &groups.back();

        StringOutputStream str(256);
        str << "Brush" << (const unsigned int) groups.size();
        current->name = str.c_str();
    }
}

void ExportData::EndBrush(void)
{
    // all faces of this brush were on the ignorelist, discard the emptygroup
    if (mode == COLLAPSE_NONE) {
        ASSERT_NOTNULL(current);
        if (current->faces.empty()) {
            groups.pop_back();
            current = 0;
        }
    }
}

void ExportData::AddBrushFace(Face &f)
{
    std::string shadername;
    GetShaderNameFromShaderPath(f.GetShader(), shadername);

    // ignore faces from ignore list
    if (ignorelist.find(shadername) != ignorelist.end()) {
        return;
    }

    if (mode == COLLAPSE_BY_MATERIAL) {
        // find a group for this material
        current = 0;
        const std::list<group>::iterator end(groups.end());
        for (std::list<group>::iterator it(groups.begin()); it != end; ++it) {
            if (it->name == shadername) {
                current = &(*it);
            }
        }

        // no group found, create one
        if (!current) {
            groups.push_back(group());
            current = &groups.back();
            current->name = shadername;
        }
    }

    ASSERT_NOTNULL(current);

    // add face to current group
    current->faces.push_back(&f);

#if GDEF_DEBUG
    globalOutputStream() << "Added Face to group " << current->name.c_str() << "\n";
#endif
}

void ExportData::GetShaderNameFromShaderPath(const char *path, std::string &name)
{
    std::string tmp(path);

    size_t last_slash = tmp.find_last_of("/");

    if (last_slash != std::string::npos && last_slash == (tmp.length() - 1)) {
        name = path;
    } else {
        name = tmp.substr(last_slash + 1, tmp.length() - last_slash);
    }

#if GDEF_DEBUG
    globalOutputStream() << "Last: " << (const unsigned int) last_slash << " " << "length: "
                         << (const unsigned int) tmp.length() << "Name: " << name.c_str() << "\n";
#endif
}

/*
    Exporter writing facedata as wavefront object
 */
class ExportDataAsWavefront : public ExportData {
private:
    bool expmat;
    bool limNames;
    bool objs;

public:
    ExportDataAsWavefront(const std::set<std::string> &_ignorelist, collapsemode _mode, bool _expmat, bool _limNames,
                          bool _objs)
            : ExportData(_ignorelist, _mode, _limNames, _objs)
    {
        expmat = _expmat;
        limNames = _limNames;
        objs = _objs;
    }

    bool WriteToFile(const std::string &path, collapsemode mode) const;
};

bool ExportDataAsWavefront::WriteToFile(const std::string &path, collapsemode mode) const
{
    std::string objFile = path;

    if (path.compare(path.length() - 4, 4, ".obj") != 0) {
        objFile += ".obj";
    }

    std::string mtlFile = objFile.substr(0, objFile.length() - 4) + ".mtl";

    std::set<std::string> materials;

    TextFileOutputStream out(objFile.c_str());

    if (out.failed()) {
        globalErrorStream() << "Unable to open file\n";
        return false;
    }

    out
            << "# Wavefront Objectfile exported with radiants brushexport plugin 3.0 by Thomas 'namespace' Nitschke, spam@codecreator.net\n\n";

    if (expmat) {
        size_t last = mtlFile.find_last_of("//");
        std::string mtllib = mtlFile.substr(last + 1, mtlFile.size() - last).c_str();
        out << "mtllib " << mtllib.c_str() << "\n";
    }

    unsigned int vertex_count = 0;

    const std::list<ExportData::group>::const_iterator gend(groups.end());
    for (std::list<ExportData::group>::const_iterator git(groups.begin()); git != gend; ++git) {
        typedef std::multimap<std::string, std::string> bm;
        bm brushMaterials;
        typedef std::pair<std::string, std::string> String_Pair;

        const std::list<const Face *>::const_iterator end(git->faces.end());

        // submesh starts here
        if (objs) {
            out << "\no ";
        } else {
            out << "\ng ";
        }
        out << git->name.c_str() << "\n";

        // material
        if (expmat && mode == COLLAPSE_ALL) {
            out << "usemtl material" << "\n\n";
            materials.insert("material");
        }

        for (std::list<const Face *>::const_iterator it(git->faces.begin()); it != end; ++it) {
            const Winding &w((*it)->getWinding());

            // vertices
            for (size_t i = 0; i < w.numpoints; ++i) {
                out << "v " << FloatFormat(w[i].vertex.x(), 1, 6) << " " << FloatFormat(w[i].vertex.z(), 1, 6) << " "
                    << FloatFormat(w[i].vertex.y(), 1, 6) << "\n";
            }
        }
        out << "\n";

        for (std::list<const Face *>::const_iterator it(git->faces.begin()); it != end; ++it) {
            const Winding &w((*it)->getWinding());

            // texcoords
            for (size_t i = 0; i < w.numpoints; ++i) {
                out << "vt " << FloatFormat(w[i].texcoord.x(), 1, 6) << " " << FloatFormat(w[i].texcoord.y(), 1, 6)
                    << "\n";
            }
        }

        for (std::list<const Face *>::const_iterator it(git->faces.begin()); it != end; ++it) {
            const Winding &w((*it)->getWinding());

            // faces
            StringOutputStream faceLine(256);
            faceLine << "\nf";
            for (size_t i = 0; i < w.numpoints; ++i, ++vertex_count) {
                faceLine << " " << vertex_count + 1 << "/" << vertex_count + 1;
            }

            if (mode != COLLAPSE_ALL) {
                materials.insert((*it)->getShader().getShader());
                brushMaterials.insert(String_Pair((*it)->getShader().getShader(), faceLine.c_str()));
            } else {
                out << faceLine.c_str();
            }
        }

        if (mode != COLLAPSE_ALL) {
            std::string lastMat;
            std::string mat;
            std::string faces;

            for (bm::iterator iter = brushMaterials.begin(); iter != brushMaterials.end(); iter++) {
                mat = (*iter).first.c_str();
                faces = (*iter).second.c_str();

                if (mat != lastMat) {
                    if (limNames && mat.size() > MAX_MATERIAL_NAME) {
                        out << "\nusemtl " << mat.substr(mat.size() - MAX_MATERIAL_NAME, mat.size()).c_str();
                    } else {
                        out << "\nusemtl " << mat.c_str();
                    }
                }

                out << faces.c_str();
                lastMat = mat;
            }
        }

        out << "\n";
    }

    if (expmat) {
        TextFileOutputStream outMtl(mtlFile.c_str());
        if (outMtl.failed()) {
            globalErrorStream() << "Unable to open material file\n";
            return false;
        }

        outMtl << "# Wavefront material file exported with NetRadiants brushexport plugin.\n";
        outMtl << "# Material Count: " << (const Unsigned) materials.size() << "\n\n";
        for (std::set<std::string>::const_iterator it(materials.begin()); it != materials.end(); ++it) {
            if (limNames && it->size() > MAX_MATERIAL_NAME) {
                outMtl << "newmtl " << it->substr(it->size() - MAX_MATERIAL_NAME, it->size()).c_str() << "\n";
            } else {
                outMtl << "newmtl " << it->c_str() << "\n";
            }
        }
    }

    return true;
}


class ForEachFace : public BrushVisitor {
public:
    ForEachFace(ExportData &_exporter)
            : exporter(_exporter)
    {}

    void visit(Face &face) const
    {
        exporter.AddBrushFace(face);
    }

private:
    ExportData &exporter;
};

class ForEachSelected : public SelectionSystem::Visitor {
public:
    ForEachSelected(ExportData &_exporter)
            : exporter(_exporter)
    {}

    void visit(scene::Instance &instance) const
    {
        BrushInstance *bptr = InstanceTypeCast<BrushInstance>::cast(instance);
        if (bptr) {
            Brush &brush(bptr->getBrush());

            exporter.BeginBrush(brush);
            ForEachFace face_vis(exporter);
            brush.forEachFace(face_vis);
            exporter.EndBrush();
        }
    }

private:
    ExportData &exporter;
};

bool ExportSelection(const std::set<std::string> &ignorelist, collapsemode m, bool exmat, const std::string &path,
                     bool limNames, bool objs)
{
    ExportDataAsWavefront exporter(ignorelist, m, exmat, limNames, objs);

    ForEachSelected vis(exporter);
    GlobalSelectionSystem().foreachSelected(vis);

    return exporter.WriteToFile(path, m);
}