// cfdgimpl.cpp
// this file is part of Context Free
// ---------------------
// Copyright (C) 2006-2008 Mark Lentczner - markl@glyphic.com
// Copyright (C) 2006-2013 John Horigan - john@glyphic.com
//
// This program 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.
//
// This program 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 this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
// 
// John Horigan can be contacted at john@glyphic.com or at
// John Horigan, 1209 Villa St., Mountain View, CA 94041-1123, USA
//
// Mark Lentczner can be contacted at markl@glyphic.com or at
// Mark Lentczner, 1209 Villa St., Mountain View, CA 94041-1123, USA
//
//


#define _USE_MATH_DEFINES 1
#include "cfdgimpl.h"
#include "builder.h"
#include "renderimpl.h"
#include "primShape.h"
#include <cassert>
#include <algorithm>
#include "astreplacement.h"
#include <limits>
#include <cstring>
#include <cmath>
#include <iomanip>
#include "agg_trans_affine_time.h"
#include <cstddef>

#include "json3.hpp"
using json = nlohmann::json;

#ifdef _WIN32
#pragma warning( disable : 4800 4189 )
#endif

#include <cmath>

using namespace AST;


CFDGImpl::CFDGImpl(AbstractSystem* m)
: mPostDtorCleanup(m), m_system(m)
{
    // Initialize the shape table with the primitive shapes so that they get the
    // shape number that matches their primitive shape number.
    for (auto&& name: primShape::shapeNames) {
        int num = encodeShapeName(name, CfdgError::Default);
        assert(num >= 0 && num < primShape::numTypes && primShape::shapeNames[num] == name);
        _unused(num);
    }
    
    initVariables();
    
    mCFDGcontents.isGlobal = true;
#ifdef EXTREME_PARAM_DEBUG
    StackRule::ParamMap.clear();
    StackRule::ParamUID = 0;
#endif
}

void
CFDGImpl::initVariables()
{
    std::string pi_name("\xcf\x80");           // UTF8-encoded pi symbol
    int pi_num = encodeShapeName(pi_name, CfdgError::Default);
    def_ptr pi = std::make_unique<ASTdefine>(pi_name, CfdgError::Default);
    pi->mExpression = std::make_unique<ASTreal>(M_PI, CfdgError::Default);
    pi->mShapeSpec.shapeType = pi_num;
    mCFDGcontents.addDefParameter(pi_num, pi.get(), CfdgError::Default, CfdgError::Default);
    mCFDGcontents.mBody.push_back(std::move(pi));

    std::initializer_list<std::string> circleNames = {
        "\xe2\x9a\xab", "\xe2\x97\x8f", "\xe2\xac\xa4"
    };
    for (auto name: circleNames) {  // no auto&&, we want to make a copy
        int num = encodeShapeName(name, CfdgError::Default);
        def_ptr def = std::make_unique<ASTdefine>(name, CfdgError::Default);
        def->mExpression = std::make_unique<ASTruleSpecifier>(primShape::circleType, "CIRCLE", nullptr, CfdgError::Default, nullptr);
        def->mShapeSpec.shapeType = num;
        mCFDGcontents.addDefParameter(num, def.get(), CfdgError::Default, CfdgError::Default);
        mCFDGcontents.mBody.push_back(std::move(def));
    }

    std::initializer_list<std::string> squareNames = {
        "\xe2\xac\x9b", "\xe2\x97\xbc", "\xe2\x97\xbe", "\xef\xbf\xad", "\xe2\x96\xa0"
    };
    for (auto name: squareNames) {
        int num = encodeShapeName(name, CfdgError::Default);
        def_ptr def = std::make_unique<ASTdefine>(name, CfdgError::Default);
        def->mExpression = std::make_unique<ASTruleSpecifier>(primShape::squareType, "SQUARE", nullptr, CfdgError::Default, nullptr);
        def->mShapeSpec.shapeType = num;
        mCFDGcontents.addDefParameter(num, def.get(), CfdgError::Default, CfdgError::Default);
        mCFDGcontents.mBody.push_back(std::move(def));
    }

    std::initializer_list<std::string> triangleNames = {
        "\xe2\x96\xb2", "\xe2\x96\xb4"
    };
    for (auto name: triangleNames) {
        int num = encodeShapeName(name, CfdgError::Default);
        def_ptr def = std::make_unique<ASTdefine>(name, CfdgError::Default);
        def->mExpression = std::make_unique<ASTruleSpecifier>(primShape::triangleType, "TRIANGLE", nullptr, CfdgError::Default, nullptr);
        def->mShapeSpec.shapeType = num;
        mCFDGcontents.addDefParameter(num, def.get(), CfdgError::Default, CfdgError::Default);
        mCFDGcontents.mBody.push_back(std::move(def));
    }
}

CFDGImpl::~CFDGImpl()
{
}

Shape
CFDGImpl::getInitialShape(RendererAST* r)
{
    Shape init;
    init.mWorldState.m_Color = HSBColor(0.0, 0.0, 0.0, 1.0);
    init.mWorldState.m_ColorTarget = HSBColor(0.0, 0.0, 0.0, 1.0);
    init.mWorldState.m_time.tend = 1.0;
    mInitShape->replace(init, r);
    init.mWorldState.m_transform.tx += mTileOffset.x;
    init.mWorldState.m_transform.ty += mTileOffset.y;
    return init;
}

const agg::rgba&
CFDGImpl::getBackgroundColor()
{
    return m_backgroundColor;
}

void
CFDGImpl::setBackgroundColor(RendererAST* r)
{
    Modification white;
    white.m_Color = HSBColor(0.0, 0.0, 1.0, 1.0);
    if (hasParameter(CFG::Background, white, r)) {
        white.m_Color.getRGBA(m_backgroundColor);
        if (!usesAlpha)
            m_backgroundColor.a = 1.0;
    }
}

const ASTrule*
CFDGImpl::findRule(int shapetype, double r)
{
    needle.mNameIndex = shapetype;
    needle.mWeight = r;
    
    auto first = lower_bound(mRules.cbegin(), mRules.cend(),
                             &needle, ASTrule::compareLT);
    if (first == mRules.cend() || (*first)->mNameIndex != shapetype)
        throw CfdgError("Cannot find a rule for a shape (very helpful I know).");
    return *first;
}

// Search for a rule in the mRules list even before it is sorted
const ASTrule*
CFDGImpl::findRule(int shapetype)
{
    auto rule = std::find_if(mRules.cbegin(), mRules.cend(),
                             [=](ASTrule* r){return r->mNameIndex == shapetype;});
    return rule == mRules.cend() ? nullptr : *rule;
}

// Adds a new rule/path to the rule container. Updates information about the rule
// in the m_shapeTypes[] vector. If the rule is known to have parameters then
// they are copied into the new rule.
bool
CFDGImpl::addRule(ASTrule* r)
{
    mRules.push_back(r);
    
    ShapeType& shapeItem = m_shapeTypes[r->mNameIndex];
    if (shapeItem.shapeType == newShape)
        shapeItem.shapeType = (r->isPath) ? pathType : ruleType; 
    if (shapeItem.parameters && !shapeItem.parameters->empty())
        r->mRuleBody.mParameters = *(shapeItem.parameters);
    shapeItem.hasRules = true;
    return shapeItem.isShape;
}

void 
CFDGImpl::addParameter(Parameter p)
{
    m_Parameters |= p;
    usesColor = m_Parameters & Color;
    usesTime = m_Parameters & Time;
    usesFrameTime = m_Parameters & FrameTime;
    usesBlendMode = m_Parameters & Blend;
}

RGBA8
CFDGImpl::getColor(const HSBColor& hsb)
{
    agg::rgba c;
    hsb.getRGBA(c);
    if (uses16bitColor) {
        return RGBA8(c);
    } else {
        agg::rgba8 c8 = agg::rgba8(c);
        return RGBA8(c8);
    }
}

bool
CFDGImpl::isTiled(agg::trans_affine* tr, double* x, double* y) const
{
    yy::location loc;
    if (!hasParameter(CFG::Tile, AST::ModType, loc)) return false;
    if (mTileMod.m_transform.sx == 0.0 || mTileMod.m_transform.sy == 0.0) return false;
    if (tr) {
        *tr = mTileMod.m_transform;
        tr->tx = tr->ty = 0.0;
    }
    if (x && y) {
        double o_x = 0.0;
        double o_y = 0.0;
        double u_x = 1.0;
        double u_y = 0.0;
        double v_x = 0.0;
        double v_y = 1.0;
        
        mTileMod.m_transform.transform(&o_x, &o_y);
        mTileMod.m_transform.transform(&u_x, &u_y);
        mTileMod.m_transform.transform(&v_x, &v_y);
        
        if (fabs(u_y - o_y) >= 0.0001 && fabs(v_x - o_x) >= 0.0001) 
            CfdgError::Error(loc, "Tile must be aligned with the X or Y axis.", m_builder);
        if ((u_x - o_x) < 0.0 || (v_y - o_y) < 0.0)
            CfdgError::Error(loc, "Tile must be in the positive X/Y quadrant.", m_builder);
        
        *x = u_x - o_x;
        *y = v_y - o_y;
    }
    return true;
}

CFDG::frieze_t
CFDGImpl::isFrieze(agg::trans_affine* tr, double* x, double* y) const
{
    yy::location loc;
    if (!hasParameter(CFG::Tile, AST::ModType, loc)) return no_frieze;
    if (mTileMod.m_transform.sx != 0.0 && mTileMod.m_transform.sy != 0.0) return no_frieze;
    if (mTileMod.m_transform.sx == 0.0 && mTileMod.m_transform.sy == 0.0) return no_frieze;
    if (tr) {
        *tr = mTileMod.m_transform;
        tr->tx = tr->ty = 0.0;
    }
    if (x && y) {
        double o_x = 0.0;
        double o_y = 0.0;
        double u_x = 1.0;
        double u_y = 0.0;
        double v_x = 0.0;
        double v_y = 1.0;
        
        mTileMod.m_transform.transform(&o_x, &o_y);
        mTileMod.m_transform.transform(&u_x, &u_y);
        mTileMod.m_transform.transform(&v_x, &v_y);
        
        if (fabs(u_y - o_y) >= 0.0001 || fabs(v_x - o_x) >= 0.0001) 
            CfdgError::Error(loc, "Frieze must be aligned with the X and Y axis.", m_builder);
        if ((u_x - o_x) < 0.0 || (v_y - o_y) < 0.0)
            CfdgError::Error(loc, "Frieze must be in the positive X/Y quadrant.", m_builder);
        
        *x = u_x - o_x;
        *y = v_y - o_y;
    }
    return mTileMod.m_transform.sx == 0.0 ? frieze_y : frieze_x;
}

bool
CFDGImpl::isTiledOrFrieze() const
{
    yy::location loc;
    return hasParameter(CFG::Tile, AST::ModType, loc);
}

bool
CFDGImpl::isSized(double* x, double* y) const
{
    yy::location loc;
    if (!hasParameter(CFG::Size, AST::ModType, loc)) return false;
    if (x) *x = mSizeMod.m_transform.sx;
    if (y) *y = mSizeMod.m_transform.sy;
    if (mSizeMod.m_transform.shx != 0.0 || mSizeMod.m_transform.shy != 0.0)
        CfdgError::Error(loc, "Size specification must not be rotated or skewed.", m_builder);
    return true;
}

bool
CFDGImpl::isTimed(agg::trans_affine_time* t) const
{
    yy::location loc;
    if (!hasParameter(CFG::Time, AST::ModType, loc)) return false;
    if (t) *t = mTimeMod.m_time;
    if (mTimeMod.m_time.tbegin >= mTimeMod.m_time.tend)
        CfdgError::Error(loc, "Time specification must have positive duration.", m_builder);
    return true;
}

void
CFDGImpl::getSymmetry(SymmList& syms, RendererAST* r)
{
    syms.clear();
    const ASTexpression* e = hasParameter(CFG::Symmetry);
    std::vector<const ASTmodification*> left = getTransforms(e, syms, r, isTiled(), mTileMod.m_transform);
    
    if (!left.empty()) {
        CfdgError::Error(left.front()->where, "At least one term was invalid", m_builder);
    }
}

void
CFDGImpl::serialize(std::ostream& out)
{
    json j{};
    json jc{};
    for (int cfg = 0; cfg < static_cast<int>(CFG::_NumberOf); ++cfg)
        if (ParamDepth[cfg] != NoParameter)
            jc[getCfgName(cfg)] = *ParamExp[cfg];
    j["configuration"] = jc;
    auto it = mCFDGcontents.mBody.begin();
    mCFDGcontents.mBody.erase(it, it + 11);     // delete the pre-defines
    j["cfdg"] = mCFDGcontents;
    out << std::setw(4) << j << std::endl;
}

bool
CFDGImpl::hasParameter(CFG name, double& value, RendererAST* r) const
{
    const ASTexpression* exp = hasParameter(name);
    if (!exp || exp->mType != AST::NumericType)
        return false;
    
    if (!exp->isConstant && !r) {
        CfdgError::Error(exp->where, "This expression must be constant", m_builder);
        return false;
    } else {
        exp->evaluate(&value, 1, r);
    }
    return true;
}

bool
CFDGImpl::hasParameter(CFG name, Modification& value, RendererAST* r) const
{
    const ASTexpression* exp = hasParameter(name);
    if (!exp || exp->mType != AST::ModType)
        return false;
    
    if (!exp->isConstant && !r) {
        CfdgError::Error(exp->where, "This expression must be constant", m_builder);
        return false;
    } else {
        exp->evaluate(value, true, r);
    }
    return true;
}

bool
CFDGImpl::hasParameter(CFG name, AST::expType t, yy::location& where) const
{
    const ASTexpression* exp = hasParameter(name);
    if (!exp || exp->mType != t)
        return false;

    where = exp->where;
    return true;
}

const ASTexpression*
CFDGImpl::hasParameter(CFG name) const
{
    assert(static_cast<std::size_t>(name) < static_cast<std::size_t>(CFG::_NumberOf));
    
    if (ParamDepth[name] == NoParameter)
        return nullptr;
    
    return ParamExp[name].get();
}

void
CFDGImpl::addParameter(CFG var, exp_ptr e, int depth)
{
    if (depth < ParamDepth[var]) {
        ParamDepth[var] = depth;
        ParamExp[var] = std::move(e);
    }
}

void
CFDGImpl::rulesLoaded()
{
    // thanks to by Brent Yorgey
    std::vector<double> weightsums( m_shapeTypes.size(), 0.0 );
    std::vector<double> percentweightsums( m_shapeTypes.size(), 0.0 );
    std::vector<double> unitweightsums( m_shapeTypes.size(), 0.0 );
    std::vector<int> rulecounts( m_shapeTypes.size(), 0 );
    std::vector<int> weightTypes( m_shapeTypes.size(), 0 );

    // first pass: sum all the weights for each shape type
    for (auto&& r: mRules) {
        if (r->weightType == ASTrule::PercentWeight) {
            percentweightsums[ r->mNameIndex ] += r->mWeight;
            if (percentweightsums[ r->mNameIndex ] > 1.0001)
                CfdgError::Error(r->mLocation, "Percentages exceed 100%", m_builder);
        } else {
            weightsums[ r->mNameIndex ] += r->mWeight;
        }
        rulecounts[ r->mNameIndex ]++;
        weightTypes[r->mNameIndex ] |= static_cast<int>(r->weightType);
    }

    // second pass: normalize each weight by dividing by the
    // total weight for that shape type
    for (auto&& r: mRules) {
        double weight = r->mWeight / weightsums[ r->mNameIndex ];   // may be infinity or NaN
        if (weightTypes[r->mNameIndex ] & static_cast<int>(ASTrule::PercentWeight)) {
            if (r->weightType == ASTrule::PercentWeight)
                weight = r->mWeight;
            else {
                weight *= 1.0 - percentweightsums[ r->mNameIndex ];
                if (percentweightsums[ r->mNameIndex ] > 0.9999)
                    CfdgError::Warning(r->mLocation, "Percentages sum to 100%, this rule has no weight");
            }
        }
        if (weightTypes[r->mNameIndex] == static_cast<int>(ASTrule::PercentWeight) &&
            fabs(percentweightsums[ r->mNameIndex ] - 1.0) > 0.0001)
        {
            CfdgError::Warning(r->mLocation, "Percentages do not sum to 100%");
        }
        if (!std::isfinite(weight)) weight = 0.0;
        unitweightsums[ r->mNameIndex ] += weight;
        if (--rulecounts[ r->mNameIndex ]) {
            r->mWeight = unitweightsums[ r->mNameIndex ];
        } else {
            // make sure that last rule of a type has a weightsum >= 1.0
            r->mWeight = 1.0;
        }
    }
    
    // third pass: sort the rules by shape type, preserving the rule order
    // with respect to rules of the same shape type
    sort(mRules.begin(), mRules.end(), ASTrule::compareLT);
    
    try {
        m_builder->mLocalStackDepth = 0;
        m_builder->mInPathContainer = false;
        mCFDGcontents.compile(CompilePhase::TypeCheck, m_builder);
        m_builder->mInPathContainer = false;
        if (!m_builder->mErrorOccured)
            mCFDGcontents.compile(CompilePhase::Simplify, m_builder);
    } catch (DeferUntilRuntime&) {
        CfdgError::Error(CfdgError::Default, "Unexpected exception during compile.");
    }
    
    // Wait until done and then update these members
    double value;
    uses16bitColor = hasParameter(CFG::ColorDepth, value, nullptr) &&
        std::floor(value) == 16.0;
    
    if (hasParameter(CFG::Color, value, nullptr))
        usesColor = value != 0.0;
    
    if (hasParameter(CFG::Alpha, value, nullptr))
        usesAlpha = value != 0.0;
    
    if (const ASTexpression* e = hasParameter(CFG::Background))
        if (const ASTmodification* m = dynamic_cast<const ASTmodification*>(e)) {
            usesAlpha = m->modData.m_Color.a < 0.0;
            for (auto& term: m->modExp)
                if (term->modType == ASTmodTerm::alpha || term->modType == ASTmodTerm::alphaTarg)
                    usesAlpha = true;
        }
}

int
CFDGImpl::numRules()
{
    return static_cast<int>(mRules.size());
}

std::string
CFDGImpl::decodeShapeName(int shapetype)
{
    if (shapetype < int(m_shapeTypes.size()))
        return m_shapeTypes[shapetype].name;
    else
        return ("**unnamed shape**");
}

const yy::location&
CFDGImpl::decodeShapeLocation(int shapetype)
{
    if (shapetype < int(m_shapeTypes.size()))
        return m_shapeTypes[shapetype].firstUse;
    else
        return CfdgError::Default;
}

int
CFDGImpl::tryEncodeShapeName(const std::string& s) const
{
    std::wstring c = m_system->normalize(s);
    return tryEncodeShapeName(c);
}

int
CFDGImpl::tryEncodeShapeName(const std::wstring& s) const
{
    for (unsigned int i = 0; i < m_shapeTypes.size(); i++) {
        if (s == m_shapeTypes[i].canonicalName) {
            return i;
        }
    }
    
    return -1;
}

int
CFDGImpl::encodeShapeName(const std::string& s, const yy::location& where)
{
    std::wstring c = m_system->normalize(s);
    int i = tryEncodeShapeName(c);
    if (i >= 0) return i;

    m_shapeTypes.emplace_back(s, std::move(c), where);
    return static_cast<int>(m_shapeTypes.size()) - 1;
}

int
CFDGImpl::getShapeType(int shapetype)
{
    return m_shapeTypes[shapetype].shapeType;
}

bool
CFDGImpl::shapeHasRules(int shapetype)
{
    if (shapetype < int(m_shapeTypes.size()))
        return m_shapeTypes[shapetype].hasRules;
    else
        return false;
}

void
CFDGImpl::setShapeHasNoParams(int shapetype, const ASTexpression* args)
{
    if (shapetype < int(m_shapeTypes.size()) && args == nullptr)
        m_shapeTypes[shapetype].shouldHaveNoParams = true;
}

bool
CFDGImpl::getShapeHasNoParams(int shapetype)
{
    if (shapetype < int(m_shapeTypes.size()))
        return m_shapeTypes[shapetype].shouldHaveNoParams;
    return false;
}

const char* 
CFDGImpl::setShapeParams(int shapetype, AST::ASTrepContainer& p, int argSize, bool isPath)
{
    ShapeType& shape = m_shapeTypes[shapetype];
    if (shape.isShape) {
        // There has been a forward declaration, so this shape declaration
        // just introduces the shape elements
        if (!(p.mParameters.empty()))
            return  "Shape has already been declared. "
                    "Parameter declaration must be on the first shape declaration only.";
        if (shape.shapeType == pathType && !isPath)
            return "Shape name already in use by another rule or path";
        if (isPath)
            return "Path name already in use by another rule or path";
        return nullptr;
    }
    if (shape.shapeType != newShape)
        return "Shape name already in use by another rule or path";
    
    if (mDefaultShape == -1 && p.mParameters.empty())
        mDefaultShape = shapetype;
    
    shape.parameters = std::make_unique<AST::ASTparameters>(p.mParameters);
    shape.isShape = true;
    shape.argSize = argSize;
    shape.shapeType = isPath ? pathType : newShape;
    return nullptr;
}

const AST::ASTparameters* 
CFDGImpl::getShapeParams(int shapetype) const
{
    if (shapetype < 0 || shapetype >= int(m_shapeTypes.size()) ||
        !m_shapeTypes[shapetype].isShape)
        return nullptr;
    return m_shapeTypes[shapetype].parameters.get();
}

int 
CFDGImpl::getShapeParamSize(int shapetype)
{
    if (shapetype < 0 || shapetype >= int(m_shapeTypes.size()))
        return 0;
    return m_shapeTypes[shapetype].argSize;
}

int
CFDGImpl::reportStackDepth(int size) 
{
    if (size > mStackSize)
        mStackSize = size;
    return mStackSize;
}

void
CFDGImpl::resetCachedPaths()
{
    for (ASTrule* rule: mRules)
        rule->mCachedPath.reset();
}

AST::ASTdefine*
CFDGImpl::declareFunction(int nameIndex, AST::ASTdefine* def)
{
    AST::ASTdefine* prev = findFunction(nameIndex);
    if (prev)
        return prev;

    mFunctions[nameIndex] = def;
    return def;
}

AST::ASTdefine*
CFDGImpl::findFunction(int nameIndex)
{
    auto fi = mFunctions.find(nameIndex);
    if (fi != mFunctions.end())
        return fi->second;
    return nullptr;
}

renderer_ptr
CFDGImpl::renderer(const cfdg_ptr& ptr, int width, int height, double minSize,
                    int variation, double border)
{
    ASTexpression* startExp = ParamExp[CFG::StartShape].get();
    
    if (!startExp) {
        if (mDefaultShape != -1) {
            // Synthesize a valid, type-checked startshape based on the
            // default shape
            ASTstartSpecifier* start = new ASTstartSpecifier(mDefaultShape, m_shapeTypes[mDefaultShape].name,
                                                             m_shapeTypes[mDefaultShape].firstUse,
                                                             {});
            start->argSource = ASTstartSpecifier::NoArgs;
            start->simpleRule = StackRule::alloc(mDefaultShape, 0, nullptr);
            start->isConstant = true;
            start->mLocality = PureLocal;
            startExp = start;
            m_system->message("Using %s as the startshape", m_shapeTypes[mDefaultShape].name.c_str());
        } else {
            m_system->message("No startshape found");
            m_system->error();
            return nullptr;
        }
    }

    if (ASTstartSpecifier* startSpec = dynamic_cast<ASTstartSpecifier*>(startExp)) {
        ParamExp[CFG::StartShape].release();
        mod_ptr mods = std::move(startSpec->mModification);
        ruleSpec_ptr start(static_cast<ASTruleSpecifier*>(startSpec));
        mInitShape = std::make_unique<ASTreplacement>(std::move(start), std::move(mods));
        mInitShape->mChildChange.addEntropy(mInitShape->mShapeSpec.entropyVal);
    } else {
        CfdgError err(startExp->where, "Type error in startshape");
        m_system->error();
        m_system->syntaxError(err);
        return nullptr;
    }

    std::unique_ptr<RendererImpl> r;
    try {
        r = std::make_unique<RendererImpl>(ptr, width, height, minSize, variation, border);
        r->mImpure = m_impure;
        r->mFrameOffset = isLooped ? 0.0 : 1.0;
        Modification tiled;
        Modification sized;
        Modification timed;
        double       maxShape;
        if (hasParameter(CFG::Tile, tiled, nullptr)) {
            mTileMod = tiled;
            mTileOffset.x = mTileMod.m_transform.tx;
            mTileOffset.y = mTileMod.m_transform.ty;
            mTileMod.m_transform.tx = mTileMod.m_transform.ty = 0.0;
        }
        if (hasParameter(CFG::Size, sized, nullptr)) {
            mSizeMod = sized;
            mTileOffset.x = mSizeMod.m_transform.tx;
            mTileOffset.y = mSizeMod.m_transform.ty;
            mSizeMod.m_transform.tx = mSizeMod.m_transform.ty = 0.0;
        }
        if (hasParameter(CFG::Time, timed, nullptr)) {
            if (timed.m_time.tend <= timed.m_time.tbegin ||
                !std::isfinite(timed.m_time.tbegin) ||
                !std::isfinite(timed.m_time.tend) ||
                !std::isfinite(timed.m_time.st))
            {
                yy::location loc;
                hasParameter(CFG::Time, AST::ModType, loc);
                CfdgError err(loc, "Illegal CF::Time specification");
                m_system->error();
                m_system->syntaxError(err);
                return nullptr;
            }
            mTimeMod = timed;
            double frame_v, ftime_v;
            bool frame = hasParameter(CFG::Frame, frame_v, nullptr);
            bool ftime = hasParameter(CFG::FrameTime, ftime_v, nullptr);
            if (frame || ftime) {
                if (frame && ftime) {
                    m_system->message("It is not necessary to specify both CF::Frame and CF::FrameTime");
                } else if (frame) {
                    ftime_v = (timed.m_time.tend - timed.m_time.tbegin) * frame_v + timed.m_time.tbegin;
                    exp_ptr e = std::make_unique<AST::ASTreal>(ftime_v, CfdgError::Default);
                    addParameter(CFG::FrameTime, std::move(e), 0);
                    m_system->message("Setting CF::FrameTime to %f from CF::Frame", ftime_v);
                } else /* if (ftime) */ {
                    frame_v = (ftime_v - timed.m_time.tbegin) / (timed.m_time.tend - timed.m_time.tbegin);
                    exp_ptr e = std::make_unique<AST::ASTreal>(frame_v, CfdgError::Default);
                    addParameter(CFG::Frame, std::move(e), 0);
                    m_system->message("Setting CF::Frame to %f from CF::FrameTime", frame_v);
                }
            }
        }
        if (hasParameter(CFG::MaxShapes, maxShape, r.get())) {
            if (maxShape > 1)
                r->setMaxShapes(static_cast<int>(maxShape));
        }
        r->initBounds();
    } catch (CfdgError& e) {
        m_system->error();
        m_system->syntaxError(e);
        return nullptr;     // deletes this
    }
    return r;
}

