VuoCompilerComposition.cc

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#include "VuoCable.hh"
#include "VuoCompilerComposition.hh"
#include "VuoCompiler.hh"
#include "VuoCompilerCable.hh"
#include "VuoCompilerComment.hh"
#include "VuoCompilerException.hh"
#include "VuoCompilerGraph.hh"
#include "VuoCompilerGraphvizParser.hh"
#include "VuoCompilerIssue.hh"
#include "VuoCompilerNode.hh"
#include "VuoCompilerPortClass.hh"
#include "VuoCompilerPublishedPort.hh"
#include "VuoCompilerSpecializedNodeClass.hh"
#include "VuoCompilerTriggerPort.hh"
#include "VuoComposition.hh"
#include "VuoGenericType.hh"
#include "VuoNode.hh"
#include "VuoNodeClass.hh"
#include "VuoComment.hh"
#include "VuoPublishedPort.hh"
#include "VuoStringUtilities.hh"
#include <sstream>
 
const string VuoCompilerComposition::defaultGraphDeclaration = "digraph G\n";
const string VuoCompilerComposition::topLevelCompositionIdentifier = "Top";
 
VuoCompilerComposition::VuoCompilerComposition(VuoComposition *baseComposition, VuoCompilerGraphvizParser *parser)
    : VuoBaseDetail<VuoComposition>("VuoCompilerComposition", baseComposition)
{
    getBase()->setCompiler(this);
 
    graph = nullptr;
    graphHash = 0;
    manuallyFirableInputNode = nullptr;
    manuallyFirableInputPort = nullptr;
    module = nullptr;
 
    if (parser)
    {
        vector<VuoNode *> nodes = parser->getNodes();
        for (vector<VuoNode *>::iterator node = nodes.begin(); node != nodes.end(); ++node)
            getBase()->addNode(*node);
 
        vector<VuoCable *> cables = parser->getCables();
        for (vector<VuoCable *>::iterator cable = cables.begin(); cable != cables.end(); ++cable)
            getBase()->addCable(*cable);
 
        vector<VuoPublishedPort *> publishedInputPorts = parser->getPublishedInputPorts();
        for (int index = 0; index < publishedInputPorts.size(); ++index)
            getBase()->addPublishedInputPort(publishedInputPorts.at(index), index);
 
        vector<VuoPublishedPort *> publishedOutputPorts = parser->getPublishedOutputPorts();
        for (int index = 0; index < publishedOutputPorts.size(); ++index)
            getBase()->addPublishedOutputPort(publishedOutputPorts.at(index), index);
 
        vector<VuoComment *> comments = parser->getComments();
        for (vector<VuoComment *>::iterator comment = comments.begin(); comment != comments.end(); ++comment)
            getBase()->addComment(*comment);
 
        manuallyFirableInputNode = parser->getManuallyFirableInputNode();
        manuallyFirableInputPort = parser->getManuallyFirableInputPort();
 
        getBase()->setMetadata(parser->getMetadata(), true);
 
        updateGenericPortTypes();
 
        for (vector<VuoNode *>::iterator node = nodes.begin(); node != nodes.end(); ++node)
            if ((*node)->hasCompiler())
                nodeGraphvizIdentifierUsed[ (*node)->getCompiler()->getGraphvizIdentifier() ] = *node;
    }
}
 
VuoCompilerComposition::~VuoCompilerComposition(void)
{
    delete graph;
    VuoCompiler::destroyLlvmModule(module);
}
 
VuoCompilerComposition * VuoCompilerComposition::newCompositionFromGraphvizDeclaration(const string &compositionGraphvizDeclaration, VuoCompiler *compiler)
{
    VuoCompilerGraphvizParser *parser = VuoCompilerGraphvizParser::newParserFromCompositionString(compositionGraphvizDeclaration, compiler);
    VuoCompilerComposition *composition = new VuoCompilerComposition(new VuoComposition(), parser);
    delete parser;
    return composition;
}
 
void VuoCompilerComposition::getChangesToReplaceNode(VuoNode *oldNode, VuoNode *newNode,
                                                     map<VuoCable *, VuoPort *> &cablesToTransferFromPort,
                                                     map<VuoCable *, VuoPort *> &cablesToTransferToPort,
                                                     set<VuoCable *> &cablesToRemove) const
{
    set<VuoCable *> cables = getBase()->getCables();
    for (set<VuoCable *>::iterator i = cables.begin(); i != cables.end(); ++i)
    {
        VuoCable *cable = *i;
 
        bool foundMismatch = false;
        if (cable->getFromNode() == oldNode)
        {
            VuoPort *oldPort = cable->getFromPort();
            VuoPort *newPort = newNode->getOutputPortWithName( oldPort->getClass()->getName() );
 
            if (portsMatch(oldPort, newPort))
                cablesToTransferFromPort[cable] = newPort;
            else
                foundMismatch = true;
        }
        if (cable->getToNode() == oldNode)
        {
            VuoPort *oldPort = cable->getToPort();
            VuoPort *newPort = newNode->getInputPortWithName( oldPort->getClass()->getName() );
 
            if (portsMatch(oldPort, newPort))
                cablesToTransferToPort[cable] = newPort;
            else
                foundMismatch = true;
        }
 
        if (foundMismatch)
        {
            cablesToRemove.insert(cable);
 
            map<VuoCable *, VuoPort *>::iterator fromIter = cablesToTransferFromPort.find(cable);
            if (fromIter != cablesToTransferFromPort.end())
                cablesToTransferFromPort.erase(fromIter);
 
            map<VuoCable *, VuoPort *>::iterator toIter = cablesToTransferToPort.find(cable);
            if (toIter != cablesToTransferToPort.end())
                cablesToTransferToPort.erase(toIter);
        }
    }
}
 
void VuoCompilerComposition::replaceNode(VuoNode *oldNode, VuoNode *newNode)
{
    map<VuoCable *, VuoPort *> cablesToTransferFromPort;
    map<VuoCable *, VuoPort *> cablesToTransferToPort;
    set<VuoCable *> cablesToRemove;
 
    getChangesToReplaceNode(oldNode, newNode, cablesToTransferFromPort, cablesToTransferToPort, cablesToRemove);
 
    getBase()->removeNode(oldNode);
    getBase()->addNode(newNode);
 
    for (map<VuoCable *, VuoPort *>::iterator i = cablesToTransferFromPort.begin(); i != cablesToTransferFromPort.end(); ++i)
        i->first->setFrom(newNode, i->second);
    for (map<VuoCable *, VuoPort *>::iterator i = cablesToTransferToPort.begin(); i != cablesToTransferToPort.end(); ++i)
        i->first->setTo(newNode, i->second);
    for (set<VuoCable *>::iterator i = cablesToRemove.begin(); i != cablesToRemove.end(); ++i)
        getBase()->removeCable(*i);
}
 
VuoCompilerGraph * VuoCompilerComposition::getCachedGraph(VuoCompiler *compiler)
{
    long currentHash = VuoCompilerGraph::getHash(this);
    bool compositionChanged = (currentHash != graphHash);
 
    bool shouldAddPublishedNodeImplementations = false;
    if (! compositionChanged && compiler)
    {
        VuoCompilerNode *publishedInputNode = graph->getPublishedInputNode();
        if (publishedInputNode && ! publishedInputNode->getBase()->getNodeClass()->getCompiler()->getEventFunction())
            shouldAddPublishedNodeImplementations = true;
    }
 
    if (compositionChanged || shouldAddPublishedNodeImplementations)
    {
        delete graph;
        graph = new VuoCompilerGraph(this, compiler);
        graphHash = currentHash;
    }
 
    return graph;
}
 
void VuoCompilerComposition::invalidateCachedGraph(void)
{
    delete graph;
    graph = nullptr;
    graphHash = 0;
}
 
void VuoCompilerComposition::check(VuoCompilerIssues *issues)
{
    checkForMissingNodeClasses(issues);
    checkForMissingTypes(issues);
    checkForEventFlowIssues(issues);
}
 
void VuoCompilerComposition::checkForMissingNodeClasses(VuoCompilerIssues *issues)
{
    set<VuoNode *> missingNodes;
    set<VuoNode *> nodes = getBase()->getNodes();
    for (set<VuoNode *>::iterator i = nodes.begin(); i != nodes.end(); ++i)
    {
        VuoNode *node = *i;
        if (! node->getNodeClass()->hasCompiler())
            missingNodes.insert(node);
    }
 
    if (! missingNodes.empty())
    {
        // Assumes the details are always displayed in plain text. Doesn't use VuoCompilerIssue's formatting.
        vector<string> uniqueNodeDetails;
        bool missingProNode = false;
        bool missingOldNode = false;
        for (set<VuoNode *>::iterator i = missingNodes.begin(); i != missingNodes.end(); ++i)
        {
            VuoNode *node = *i;
 
            string nodeDetail = node->getTitle() + " (" + (*i)->getNodeClass()->getClassName() + ")";
 
#if VUO_PRO
            if (node->getNodeClass()->isPro())
            {
                nodeDetail += " [Vuo Pro]";
                missingProNode = true;
            }
#endif
 
            if (node->getNodeClass()->getDescription().find("This node was updated or removed in Vuo 0.9 or earlier.") != string::npos)
            {
                nodeDetail += " [Vuo 0.9 or earlier]";
                missingOldNode = true;
            }
 
            if (find(uniqueNodeDetails.begin(), uniqueNodeDetails.end(), nodeDetail) == uniqueNodeDetails.end())
                uniqueNodeDetails.push_back(nodeDetail);
        }
        sort(uniqueNodeDetails.begin(), uniqueNodeDetails.end());
        string details = "\n\n" + VuoStringUtilities::join(uniqueNodeDetails, "\n");
 
        string hint;
        string linkUrl;
        string linkText;
 
        if (missingProNode)
        {
            hint += "Some of the non-installed nodes are Pro nodes. "
                    "%link to enable Pro nodes.";
            linkUrl = "https://vuo.org/buy";
            linkText = "Upgrade to Vuo Pro";
        }
 
        // Assumes the hint is always displayed in HTML. Doesn't use VuoCompilerIssue's formatting.
        if (missingProNode && missingOldNode)
            hint += "<br><br>";
 
        if (missingOldNode)
        {
            hint += "Some of the non-installed nodes were updated or removed in Vuo 0.9 or earlier. "
                    "To work with this composition in Vuo 1.0 or later, first make a "
                    "backup copy of the composition, then open the composition in Vuo 0.9 and save it. "
                    "This will automatically upgrade the composition so you can use it in Vuo 1.0 or later.";
        }
 
        // If changing this text, also change VuoEditorWindow::hideBuildActivityIndicator() and VuoEditorWindow::displayExportErrorBox().
        string summary = "Nodes not installed";
 
        VuoCompilerIssue issue(VuoCompilerIssue::Error, "opening composition", "", summary, details);
        issue.setNodes(missingNodes);
        issue.setHint(hint);
        issue.setLink(linkUrl, linkText);
        issues->append(issue);
        throw VuoCompilerException(issues, false);
    }
}
 
void VuoCompilerComposition::checkForMissingTypes(VuoCompilerIssues *issues)
{
    map<string, set<string> > missingTypes;
    for (VuoNode *node : getBase()->getNodes())
    {
        if (! node->getNodeClass()->hasCompiler())
            continue;
 
        vector<VuoPort *> ports;
        vector<VuoPort *> inputPorts = node->getInputPorts();
        ports.insert(ports.end(), inputPorts.begin(), inputPorts.end());
        vector<VuoPort *> outputPorts = node->getOutputPorts();
        ports.insert(ports.end(), outputPorts.begin(), outputPorts.end());
 
        for (VuoPort *port : ports)
        {
            VuoType *type = static_cast<VuoCompilerPort *>(port->getCompiler())->getDataVuoType();
            if (type && ! type->hasCompiler() && ! dynamic_cast<VuoGenericType *>(type))
                missingTypes[type->getModuleKey()].insert(node->getNodeClass()->getClassName());
        }
    }
 
    if (! missingTypes.empty())
    {
        for (auto i : missingTypes)
        {
            vector<string> nodeClassNames(i.second.begin(), i.second.end());
            std::sort(nodeClassNames.begin(), nodeClassNames.end());
 
            string summary = "Data type not installed";
            string details = i.first + " — used by " + VuoStringUtilities::join(nodeClassNames, ", ");
            string hint = "Check with the developer of the nodes that use this data type.";
 
            VuoCompilerIssue issue(VuoCompilerIssue::Error, "opening composition", "", summary, details);
            issue.setHint(hint);
            issues->append(issue);
        }
 
        throw VuoCompilerException(issues, false);
    }
}
 
void VuoCompilerComposition::checkForEventFlowIssues(VuoCompilerIssues *issues)
{
    checkForEventFlowIssues(set<VuoCompilerCable *>(), issues);
}
 
void VuoCompilerComposition::checkForEventFlowIssues(set<VuoCompilerCable *> potentialCables, VuoCompilerIssues *issues)
{
    VuoCompilerGraph *graph;
    if (! potentialCables.empty())
        graph = new VuoCompilerGraph(this, nullptr, potentialCables);
    else
        graph = getCachedGraph();
 
    graph->checkForInfiniteFeedback(issues);
    graph->checkForDeadlockedFeedback(issues);
 
    if (! potentialCables.empty())
        delete graph;
}
 
set< set<VuoCompilerPort *> > VuoCompilerComposition::groupGenericPortsByType(void)
{
    set< set<VuoCompilerPort *> > setsOfConnectedGenericPorts;
 
    // Put the generic ports into sets by node, with additional sets for published input and output ports.
    set< pair< vector<VuoPort *>, VuoNode *> > portsGroupedByNode;
    set<VuoNode *> nodes = getBase()->getNodes();
    for (set<VuoNode *>::iterator i = nodes.begin(); i != nodes.end(); ++i)
    {
        VuoNode *node = *i;
        if (! node->hasCompiler())
            continue;
 
        vector<VuoPort *> inputPorts = node->getInputPorts();
        vector<VuoPort *> outputPorts = node->getOutputPorts();
        vector<VuoPort *> ports;
        ports.insert(ports.end(), inputPorts.begin(), inputPorts.end());
        ports.insert(ports.end(), outputPorts.begin(), outputPorts.end());
 
        portsGroupedByNode.insert( make_pair(ports, node) );
    }
    vector<VuoPublishedPort *> publishedInputPorts = getBase()->getPublishedInputPorts();
    vector<VuoPublishedPort *> publishedOutputPorts = getBase()->getPublishedOutputPorts();
    vector<VuoPort *> publishedInputBasePorts( publishedInputPorts.begin(), publishedInputPorts.end() );
    vector<VuoPort *> publishedOutputBasePorts( publishedOutputPorts.begin(), publishedOutputPorts.end() );
    portsGroupedByNode.insert( make_pair(publishedInputBasePorts, static_cast<VuoNode *>(NULL)) );
    portsGroupedByNode.insert( make_pair(publishedOutputBasePorts, static_cast<VuoNode *>(NULL)) );
 
    // Within each set of generic ports by node (or published ports), group the generic ports into sets by generic type.
    for (set< pair< vector<VuoPort *>, VuoNode* > >::iterator i = portsGroupedByNode.begin(); i != portsGroupedByNode.end(); ++i)
    {
        vector<VuoPort *> ports = i->first;
 
        map<string, set<VuoCompilerPort *> > genericPortsForType;
        for (vector<VuoPort *>::iterator j = ports.begin(); j != ports.end(); ++j)
        {
            VuoCompilerPort *port = static_cast<VuoCompilerPort *>((*j)->getCompiler());
            VuoGenericType *genericType = dynamic_cast<VuoGenericType *>(port->getDataVuoType());
 
            if (genericType)
            {
                string innermostGenericTypeName = VuoType::extractInnermostTypeName(genericType->getModuleKey());
                genericPortsForType[innermostGenericTypeName].insert(port);
            }
        }
 
        for (map<string, set<VuoCompilerPort *> >::iterator j = genericPortsForType.begin(); j != genericPortsForType.end(); ++j)
        {
            set<VuoCompilerPort *> genericPorts = j->second;
            setsOfConnectedGenericPorts.insert(genericPorts);
        }
    }
 
    // Merge sets of generic ports from different nodes that are connected through a data-carrying cable.
    set<VuoCable *> cables = getBase()->getCables();
    for (set<VuoCable *>::iterator i = cables.begin(); i != cables.end(); ++i)
    {
        VuoCable *cable = *i;
 
        if (! (cable->getFromPort() && cable->getFromPort()->hasCompiler() &&
               cable->getToPort() && cable->getToPort()->hasCompiler() &&
               cable->getCompiler()->carriesData()))
            continue;
 
        VuoCompilerPort *fromPort = static_cast<VuoCompilerPort *>(cable->getFromPort()->getCompiler());
        VuoCompilerPort *toPort = static_cast<VuoCompilerPort *>(cable->getToPort()->getCompiler());
        set< set<VuoCompilerPort *> >::iterator fromSetIter = setsOfConnectedGenericPorts.end();  // the set containing fromPort
        set< set<VuoCompilerPort *> >::iterator toSetIter = setsOfConnectedGenericPorts.end();  // the set containing toPort
        for (set< set<VuoCompilerPort *> >::iterator j = setsOfConnectedGenericPorts.begin(); j != setsOfConnectedGenericPorts.end(); ++j)
        {
            if (j->find(fromPort) != j->end())
                fromSetIter = j;
            if (j->find(toPort) != j->end())
                toSetIter = j;
        }
        if (fromSetIter != setsOfConnectedGenericPorts.end() && toSetIter != setsOfConnectedGenericPorts.end() &&
                fromSetIter != toSetIter)
        {
            set<VuoCompilerPort *> mergedSet;
            mergedSet.insert(fromSetIter->begin(), fromSetIter->end());
            mergedSet.insert(toSetIter->begin(), toSetIter->end());
            setsOfConnectedGenericPorts.insert(mergedSet);
            setsOfConnectedGenericPorts.erase(fromSetIter);
            setsOfConnectedGenericPorts.erase(toSetIter);
        }
    }
 
    return setsOfConnectedGenericPorts;
}
 
void VuoCompilerComposition::updateGenericPortTypes(void)
{
    set< set<VuoCompilerPort *> > setsOfConnectedGenericPorts = groupGenericPortsByType();
 
    // Give each set of connected generic ports a unique generic type.
    set<string> usedTypeNames;
    for (set< set<VuoCompilerPort *> >::iterator i = setsOfConnectedGenericPorts.begin(); i != setsOfConnectedGenericPorts.end(); ++i)
    {
        set<VuoCompilerPort *> connectedGenericPorts = *i;
 
        // Find the smallest-numbered generic type within the set that isn't already used by another set.
        // If no such type exists, create a fresh type.
 
        vector<string> sortedTypeNames;
        for (set<VuoCompilerPort *>::iterator j = connectedGenericPorts.begin(); j != connectedGenericPorts.end(); ++j)
        {
            VuoCompilerPort *port = *j;
            VuoGenericType *genericTypeFromPort = static_cast<VuoGenericType *>(port->getDataVuoType());
            VuoCompilerPortClass *portClass = static_cast<VuoCompilerPortClass *>(port->getBase()->getClass()->getCompiler());
            VuoGenericType *genericTypeFromPortClass = static_cast<VuoGenericType *>(portClass->getDataVuoType());
            if (genericTypeFromPort != genericTypeFromPortClass)
            {
                string typeName = VuoGenericType::extractInnermostTypeName( genericTypeFromPort->getModuleKey() );
                sortedTypeNames.push_back(typeName);
            }
        }
        VuoGenericType::sortGenericTypeNames(sortedTypeNames);
 
        string commonTypeName;
        for (vector<string>::iterator j = sortedTypeNames.begin(); j != sortedTypeNames.end(); ++j)
        {
            string portType = *j;
            if (usedTypeNames.find(portType) == usedTypeNames.end())
            {
                commonTypeName = portType;
                break;
            }
        }
 
        if (commonTypeName.empty())
            commonTypeName = createFreshGenericTypeName();
 
        usedTypeNames.insert(commonTypeName);
 
        // Form the set of compatible types for each composition-level generic type by finding the intersection of
        // the sets of compatible types for each node-class-level generic type.
        vector<string> compatibleTypeNames;
        for (set<VuoCompilerPort *>::iterator j = connectedGenericPorts.begin(); j != connectedGenericPorts.end(); ++j)
        {
            VuoCompilerPort *port = *j;
            VuoCompilerPortClass *portClass = static_cast<VuoCompilerPortClass *>(port->getBase()->getClass()->getCompiler());
            VuoGenericType *genericTypeFromPortClass = static_cast<VuoGenericType *>(portClass->getDataVuoType());
            VuoGenericType::Compatibility compatibility;
            vector<string> compatibleTypeNamesForPort = genericTypeFromPortClass->getCompatibleSpecializedTypes(compatibility);
            vector<string> innermostCompatibleTypeNamesForPort;
            for (vector<string>::iterator k = compatibleTypeNamesForPort.begin(); k != compatibleTypeNamesForPort.end(); ++k)
                innermostCompatibleTypeNamesForPort.push_back( VuoType::extractInnermostTypeName(*k) );
 
            if (! innermostCompatibleTypeNamesForPort.empty())
            {
                if (compatibleTypeNames.empty())
                    compatibleTypeNames = innermostCompatibleTypeNamesForPort;
                else
                {
                    for (int k = compatibleTypeNames.size() - 1; k >= 0; --k)
                        if (find(innermostCompatibleTypeNamesForPort.begin(), innermostCompatibleTypeNamesForPort.end(), compatibleTypeNames[k]) ==
                                innermostCompatibleTypeNamesForPort.end())
                            compatibleTypeNames.erase(compatibleTypeNames.begin() + k);
                }
            }
        }
 
        // Apply the composition-level generic type name to each port.
        for (set<VuoCompilerPort *>::iterator j = connectedGenericPorts.begin(); j != connectedGenericPorts.end(); ++j)
        {
            VuoCompilerPort *port = *j;
            VuoCompilerPortClass *portClass = static_cast<VuoCompilerPortClass *>(port->getBase()->getClass()->getCompiler());
            VuoGenericType *genericTypeFromPortClass = static_cast<VuoGenericType *>(portClass->getDataVuoType());
 
            string typeNameForPort = VuoGenericType::replaceInnermostGenericTypeName(genericTypeFromPortClass->getModuleKey(), commonTypeName);
            vector<string> compatibleTypeNamesForPort;
            string prefix = (VuoType::isListTypeName(typeNameForPort) ? VuoType::listTypeNamePrefix : "");
            for (vector<string>::iterator k = compatibleTypeNames.begin(); k != compatibleTypeNames.end(); ++k)
                compatibleTypeNamesForPort.push_back(prefix + *k);
 
            VuoGenericType *commonTypeForPort = new VuoGenericType(typeNameForPort, compatibleTypeNamesForPort);
            port->setDataVuoType(commonTypeForPort);
        }
    }
 
    // Update the list of type suffixes that can't currently be used when creating fresh types.
    for (map<unsigned int, bool>::iterator i = genericTypeSuffixUsed.begin(); i != genericTypeSuffixUsed.end(); ++i)
    {
        unsigned int suffix = i->first;
        bool used = (usedTypeNames.find( VuoGenericType::createGenericTypeName(suffix) ) != usedTypeNames.end());
        genericTypeSuffixUsed[suffix] = used;
    }
}
 
string VuoCompilerComposition::createFreshGenericTypeName(void)
{
    for (unsigned int i = 1; ; ++i)
    {
        if (! genericTypeSuffixUsed[i])
        {
            genericTypeSuffixUsed[i] = true;
            return VuoGenericType::createGenericTypeName(i);
        }
    }
}
 
set<VuoPort *> VuoCompilerComposition::getCorrelatedGenericPorts(VuoNode *entryNode, VuoPort *entryPort, bool useOriginalType)
{
 
    auto getGenericTypeName = [&useOriginalType] (VuoNode *node, VuoPort *port)
    {
        VuoGenericType *genericType = nullptr;
 
        if (useOriginalType)
        {
            if (node && node->hasCompiler())
            {
                VuoCompilerNodeClass *nodeClass = node->getNodeClass()->getCompiler();
                VuoCompilerSpecializedNodeClass *specializedNodeClass = dynamic_cast<VuoCompilerSpecializedNodeClass *>(nodeClass);
                if (specializedNodeClass)
                    genericType = dynamic_cast<VuoGenericType *>(specializedNodeClass->getOriginalPortType(port->getClass()));
            }
        }
        else
        {
            VuoCompilerPort *compilerPort = static_cast<VuoCompilerPort *>(port->getCompiler());
            genericType = dynamic_cast<VuoGenericType *>(compilerPort->getDataVuoType());
        }
 
        return genericType ? VuoType::extractInnermostTypeName(genericType->getModuleKey()) : "";
    };
 
    set<VuoPort *> correlatedPorts;
    set<VuoNode *> nodesEnqueuedOrVisited;
    list< pair<VuoNode *, string> > nodesToVisit;
 
    string entryGenericType = getGenericTypeName(entryNode, entryPort);
    if (! entryGenericType.empty())
    {
        nodesToVisit.push_back( make_pair(entryNode, entryGenericType) );
        nodesEnqueuedOrVisited.insert(entryNode);
    }
 
    while (! nodesToVisit.empty())
    {
        VuoNode *currNode = nodesToVisit.front().first;
        string currGenericType = nodesToVisit.front().second;
        nodesToVisit.pop_front();
 
        // Find all ports on the node that share (or would share if unspecialized) the same data type.
 
        list<VuoPort *> correlatedPortsOnNode;
        for (VuoPort *currPort : currNode->getInputPorts())
            if (getGenericTypeName(currNode, currPort) == currGenericType)
                correlatedPortsOnNode.push_back(currPort);
        for (VuoPort *currPort : currNode->getOutputPorts())
            if (getGenericTypeName(currNode, currPort) == currGenericType)
                correlatedPortsOnNode.push_back(currPort);
 
        correlatedPorts.insert(correlatedPortsOnNode.begin(), correlatedPortsOnNode.end());
 
        // Follow all data-carrying cables from those ports to other nodes.
 
        for (VuoPort *port : correlatedPortsOnNode)
        {
            for (VuoCable *cable : port->getConnectedCables())
            {
                if (! (cable->hasCompiler() && cable->getCompiler()->carriesData()))
                    continue;
 
                VuoNode *otherNode = nullptr;
                VuoPort *otherPort = nullptr;
                if (currNode != cable->getFromNode())
                {
                    otherNode = cable->getFromNode();
                    otherPort = cable->getFromPort();
                }
                else if (currNode != cable->getToNode())
                {
                    otherNode = cable->getToNode();
                    otherPort = cable->getToPort();
                }
 
                if (! otherPort)
                    continue;
 
                if (nodesEnqueuedOrVisited.find(otherNode) == nodesEnqueuedOrVisited.end())
                {
                    string otherGenericType = getGenericTypeName(otherNode, otherPort);
                    if (! otherGenericType.empty())
                    {
                        nodesToVisit.push_back( make_pair(otherNode, otherGenericType) );
                        nodesEnqueuedOrVisited.insert(otherNode);
                    }
                }
            }
        }
    }
 
    return correlatedPorts;
}
 
VuoPort * VuoCompilerComposition::findNearestUpstreamTriggerPort(VuoNode *node)
{
    VuoCompilerGraph *graph = getCachedGraph();
    VuoCompilerTriggerPort *trigger = graph->findNearestUpstreamTrigger(node->getCompiler());
    return trigger ? trigger->getBase() : NULL;
}
 
void VuoCompilerComposition::setModule(Module *module)
{
    this->module = module;
}
 
Module * VuoCompilerComposition::takeModule(void)
{
    Module *takenModule = module;
    module = NULL;
    return takenModule;
}
 
void VuoCompilerComposition::setUniqueGraphvizIdentifierForNode(VuoNode *node, const string &preferredIdentifier, const string &identifierPrefix)
{
    if (! node->hasCompiler())
        return;
 
    for (VuoNode *currNode : getBase()->getNodes())
        if (currNode != node && currNode->hasCompiler())
            nodeGraphvizIdentifierUsed[ currNode->getCompiler()->getGraphvizIdentifier() ] = currNode;
 
    auto isIdentifierAvailable = [this, node] (const string &identifier)
    {
        auto it = nodeGraphvizIdentifierUsed.find(identifier);
        if (it == nodeGraphvizIdentifierUsed.end())
            return true;
 
        return it->second == node;
    };
 
    string nonEmptyPreferredIdentifier = (! preferredIdentifier.empty() ? preferredIdentifier : node->getCompiler()->getGraphvizIdentifier());
    string nonEmptyIdentifierPrefix = (! identifierPrefix.empty() ? identifierPrefix : node->getCompiler()->getGraphvizIdentifierPrefix());
 
    string uniqueIdentifier = VuoStringUtilities::formUniqueIdentifier(isIdentifierAvailable, nonEmptyPreferredIdentifier, nonEmptyIdentifierPrefix);
 
    nodeGraphvizIdentifierUsed[uniqueIdentifier] = node;
    node->getCompiler()->setGraphvizIdentifier(uniqueIdentifier);
}
 
void VuoCompilerComposition::clearGraphvizNodeIdentifierHistory()
{
    nodeGraphvizIdentifierUsed.clear();
}
 
void VuoCompilerComposition::setUniqueGraphvizIdentifierForComment(VuoComment *comment)
{
    if (! comment->hasCompiler())
        return;
 
    for (VuoComment *currComment : getBase()->getComments())
        if (currComment != comment && currComment->hasCompiler())
            commentGraphvizIdentifierUsed[ currComment->getCompiler()->getGraphvizIdentifier() ] = currComment;
 
    auto isIdentifierAvailable = [this, comment] (const string &identifier)
    {
        auto it = commentGraphvizIdentifierUsed.find(identifier);
        if (it == commentGraphvizIdentifierUsed.end())
            return true;
 
        return it->second == comment;
    };
 
    string uniqueIdentifier = VuoStringUtilities::formUniqueIdentifier(isIdentifierAvailable,
                                                                       comment->getCompiler()->getGraphvizIdentifier(),
                                                                       comment->getCompiler()->getGraphvizIdentifierPrefix());
    commentGraphvizIdentifierUsed[uniqueIdentifier] = comment;
    comment->getCompiler()->setGraphvizIdentifier(uniqueIdentifier);
}
 
void VuoCompilerComposition::clearGraphvizCommentIdentifierHistory()
{
    commentGraphvizIdentifierUsed.clear();
}
 
void VuoCompilerComposition::setManuallyFirableInputPort(VuoNode *nodeContainingPort, VuoPort *portFiredInto)
{
    this->manuallyFirableInputNode = nodeContainingPort;
    this->manuallyFirableInputPort = portFiredInto;
}
 
VuoNode * VuoCompilerComposition::getManuallyFirableInputNode(void)
{
    return manuallyFirableInputNode;
}
 
VuoPort * VuoCompilerComposition::getManuallyFirableInputPort(void)
{
    return manuallyFirableInputPort;
}
 
string VuoCompilerComposition::getGraphvizDeclaration(VuoProtocol *activeProtocol, string header, string footer)
{
    return getGraphvizDeclarationForComponents(getBase()->getNodes(),
                                               getBase()->getCables(),
                                               getBase()->getComments(),
                                               getBase()->getProtocolAwarePublishedPortOrder(activeProtocol, true),
                                               getBase()->getProtocolAwarePublishedPortOrder(activeProtocol, false),
                                               header,
                                               footer);
}
 
string VuoCompilerComposition::getGraphvizDeclarationForComponents(set<VuoNode *> nodeSet,
                                                                   set<VuoCable *> cableSet,
                                                                   set<VuoComment *> commentSet,
                                                                   vector<VuoPublishedPort *> publishedInputPorts,
                                                                   vector<VuoPublishedPort *> publishedOutputPorts,
                                                                   string header, string footer, double xPositionOffset, double yPositionOffset)
{
    // Sort nodes.
    vector<VuoNode *> nodes;
    for (set<VuoNode *>::iterator i = nodeSet.begin(); i != nodeSet.end(); ++i)
        nodes.push_back(*i);
 
    sort(nodes.begin(), nodes.end(), compareGraphvizIdentifiersOfNodes);
 
    // Sort cables.
    vector<VuoCable *> cables;
    for (set<VuoCable *>::iterator i = cableSet.begin(); i != cableSet.end(); ++i)
        cables.push_back(*i);
 
    sort(cables.begin(), cables.end(), compareGraphvizIdentifiersOfCables);
 
    // Sort comments.
    vector<VuoComment *> comments;
    for (set<VuoComment *>::iterator i = commentSet.begin(); i != commentSet.end(); ++i)
        comments.push_back(*i);
 
    sort(comments.begin(), comments.end(), compareGraphvizIdentifiersOfComments);
 
    string compositionHeader = (! header.empty()? header : defaultGraphDeclaration);
    string compositionFooter = (! footer.empty()? footer : "\n");
 
    ostringstream output;
    string nodeCommentSectionDivider = "\n";
    if ((nodes.empty() && publishedInputPorts.empty() && publishedOutputPorts.empty()) ||
            (comments.empty() && cables.empty()))
        nodeCommentSectionDivider = "";
 
    string commentCableSectionDivider = "\n";
    if (comments.empty() || cables.empty())
        commentCableSectionDivider = "";
 
    // Print header
    output << compositionHeader;
    output << "{" << endl;
 
    // Print nodes
    for (vector<VuoNode *>::iterator i = nodes.begin(); i != nodes.end(); ++i)
    {
        string nodeDeclaration = ((*i)->hasCompiler() ?
                                      (*i)->getCompiler()->getGraphvizDeclaration(true, xPositionOffset, yPositionOffset,
                                                                                  manuallyFirableInputNode == *i ? manuallyFirableInputPort : nullptr) :
                                      (*i)->getRawGraphvizDeclaration());
        output << nodeDeclaration << endl;
    }
 
    // Print pseudo-nodes for published ports
    if (! publishedInputPorts.empty())
    {
        output << VuoNodeClass::publishedInputNodeIdentifier << " [type=\"" << VuoNodeClass::publishedInputNodeClassName << "\" label=\"" << VuoNodeClass::publishedInputNodeIdentifier;
        for (vector<VuoPublishedPort *>::iterator i = publishedInputPorts.begin(); i != publishedInputPorts.end(); ++i)
            output << "|<" << (*i)->getClass()->getName() << ">" << (*i)->getClass()->getName() << "\\r";
        output << "\"";
        for (vector<VuoPublishedPort *>::iterator i = publishedInputPorts.begin(); i != publishedInputPorts.end(); ++i)
            output << static_cast<VuoCompilerPublishedPort *>((*i)->getCompiler())->getGraphvizAttributes();
        output << "];" << endl;
    }
    if (! publishedOutputPorts.empty())
    {
        output << VuoNodeClass::publishedOutputNodeIdentifier <<  " [type=\"" << VuoNodeClass::publishedOutputNodeClassName << "\" label=\"" << VuoNodeClass::publishedOutputNodeIdentifier;
        for (vector<VuoPublishedPort *>::iterator i = publishedOutputPorts.begin(); i != publishedOutputPorts.end(); ++i)
            output << "|<" << (*i)->getClass()->getName() << ">" << (*i)->getClass()->getName() << "\\l";
        output << "\"";
 
        for (vector<VuoPublishedPort *>::iterator i = publishedOutputPorts.begin(); i != publishedOutputPorts.end(); ++i)
            output << static_cast<VuoCompilerPublishedPort *>((*i)->getCompiler())->getGraphvizAttributes();
 
        output << "];" << endl;
    }
 
    output << nodeCommentSectionDivider;
 
    // Print comments
    for (vector<VuoComment *>::iterator i = comments.begin(); i != comments.end(); ++i)
    {
        string commentDeclaration = ((*i)->hasCompiler() ?
                                      (*i)->getCompiler()->getGraphvizDeclaration(xPositionOffset, yPositionOffset) : "");
        output << commentDeclaration << endl;
    }
 
    output << commentCableSectionDivider;
 
    // Print cables
    for (vector<VuoCable *>::iterator i = cables.begin(); i != cables.end(); ++i)
    {
        VuoCable *cable = *i;
        output << cable->getCompiler()->getGraphvizDeclaration() << endl;
    }
 
    output << "}";
    output << compositionFooter;
 
    return output.str();
}
 
VuoCompilerTargetSet VuoCompilerComposition::getCompatibleTargets()
{
    VuoCompilerTargetSet compositeTarget;
    for (auto node : getBase()->getNodes())
        compositeTarget.restrictToBeCompatibleWithAllOf(node->getNodeClass()->getCompiler()->getCompatibleTargets());
    return compositeTarget;
}
 
bool VuoCompilerComposition::compareGraphvizIdentifiersOfNodes(VuoNode *lhs, VuoNode *rhs)
{
    string lhsIdentifier = (lhs->hasCompiler() ? lhs->getCompiler()->getGraphvizIdentifier() : lhs->getRawGraphvizIdentifier());
    string rhsIdentifier = (rhs->hasCompiler() ? rhs->getCompiler()->getGraphvizIdentifier() : rhs->getRawGraphvizIdentifier());
    return lhsIdentifier.compare(rhsIdentifier) < 0;
}
 
bool VuoCompilerComposition::compareGraphvizIdentifiersOfCables(VuoCable *lhs, VuoCable *rhs)
{
    string lhsIdentifier = (lhs->hasCompiler() ? lhs->getCompiler()->getGraphvizDeclaration() : "");
    string rhsIdentifier = (rhs->hasCompiler() ? rhs->getCompiler()->getGraphvizDeclaration() : "");
    return lhsIdentifier.compare(rhsIdentifier) < 0;
}
 
bool VuoCompilerComposition::compareGraphvizIdentifiersOfComments(VuoComment *lhs, VuoComment *rhs)
{
    string lhsIdentifier = (lhs->hasCompiler() ? lhs->getCompiler()->getGraphvizIdentifier() : "");
    string rhsIdentifier = (rhs->hasCompiler() ? rhs->getCompiler()->getGraphvizIdentifier() : "");
    return lhsIdentifier.compare(rhsIdentifier) < 0;
}
 
bool VuoCompilerComposition::portsMatch(VuoPort *oldPort, VuoPort *newPort)
{
    if (! oldPort || ! newPort)
        return false;
 
    string oldPortName = oldPort->getClass()->getName();
    string newPortName = newPort->getClass()->getName();
    if (oldPortName == newPortName)
    {
        if (oldPort->hasCompiler() && newPort->hasCompiler())
        {
            VuoType *oldType = static_cast<VuoCompilerPort *>( oldPort->getCompiler() )->getDataVuoType();
            VuoType *newType = static_cast<VuoCompilerPort *>( newPort->getCompiler() )->getDataVuoType();
            if (oldType == newType)
                return true;
        }
        else
            return true;
    }
 
    return false;
}
 
bool VuoCompilerComposition::portClassesMatch(VuoPortClass *oldPortClass, VuoPortClass *newPortClass)
{
    if (! oldPortClass || ! newPortClass)
        return false;
 
    string oldPortName = oldPortClass->getName();
    string newPortName = newPortClass->getName();
    if (oldPortName == newPortName)
    {
        if (oldPortClass->hasCompiler() && newPortClass->hasCompiler())
        {
            VuoType *oldType = static_cast<VuoCompilerPortClass *>( oldPortClass->getCompiler() )->getDataVuoType();
            VuoType *newType = static_cast<VuoCompilerPortClass *>( newPortClass->getCompiler() )->getDataVuoType();
            if (oldType == newType)
                return true;
        }
        else
            return true;
    }
 
    return false;
}