#include "CSGTermEvaluator.h"
#include "visitor.h"
#include "state.h"
#include "csgterm.h"
#include "module.h"
#include "csgnode.h"
#include "transformnode.h"
#include "colornode.h"
#include "rendernode.h"
#include "cgaladvnode.h"
#include "printutils.h"
#include "PolySetEvaluator.h"

#include <string>
#include <map>
#include <list>
#include <sstream>
#include <iostream>
#include <assert.h>
#include <cstddef>
#include <boost/foreach.hpp>

/*!
	\class CSGTermEvaluator

	A visitor responsible for creating a tree of CSGTerm nodes used for rendering
	with OpenCSG.
*/

shared_ptr<CSGTerm> CSGTermEvaluator::evaluateCSGTerm(const AbstractNode &node, 
																					 std::vector<shared_ptr<CSGTerm> > &highlights, 
																					 std::vector<shared_ptr<CSGTerm> > &background)
{
	Traverser evaluate(*this, node, Traverser::PRE_AND_POSTFIX);
	evaluate.execute();
	highlights = this->highlights;
	background = this->background;
	return this->stored_term[node.index()];
}

void CSGTermEvaluator::applyToChildren(const AbstractNode &node, CSGTermEvaluator::CsgOp op)
{
	shared_ptr<CSGTerm> t1;
	BOOST_FOREACH(const AbstractNode *chnode, this->visitedchildren[node.index()]) {
		shared_ptr<CSGTerm> t2(this->stored_term[chnode->index()]);
		this->stored_term.erase(chnode->index());
		if (t2 && !t1) {
			t1 = t2;
		} else if (t2 && t1) {
			if (op == CSGT_UNION) {
				t1 = CSGTerm::createCSGTerm(CSGTerm::TYPE_UNION, t1, t2);
			} else if (op == CSGT_DIFFERENCE) {
				t1 = CSGTerm::createCSGTerm(CSGTerm::TYPE_DIFFERENCE, t1, t2);
			} else if (op == CSGT_INTERSECTION) {
				t1 = CSGTerm::createCSGTerm(CSGTerm::TYPE_INTERSECTION, t1, t2);
			}
		}
	}
	if (t1 && node.modinst->isHighlight()) {
		t1->flag = CSGTerm::FLAG_HIGHLIGHT;
		this->highlights.push_back(t1);
	}
	if (t1 && node.modinst->isBackground()) {
		this->background.push_back(t1);
		t1.reset(); // don't propagate background tagged nodes
	}
	this->stored_term[node.index()] = t1;
}

Response CSGTermEvaluator::visit(State &state, const AbstractNode &node)
{
	if (state.isPostfix()) {
		applyToChildren(node, CSGT_UNION);
		addToParent(state, node);
	}
	return ContinueTraversal;
}

Response CSGTermEvaluator::visit(State &state, const AbstractIntersectionNode &node)
{
	if (state.isPostfix()) {
		applyToChildren(node, CSGT_INTERSECTION);
		addToParent(state, node);
	}
	return ContinueTraversal;
}

static shared_ptr<CSGTerm> evaluate_csg_term_from_ps(const State &state, 
																					std::vector<shared_ptr<CSGTerm> > &highlights, 
																					std::vector<shared_ptr<CSGTerm> > &background, 
																					const shared_ptr<PolySet> &ps, 
																					const ModuleInstantiation *modinst, 
																					const AbstractNode &node)
{
	std::stringstream stream;
	stream << node.name() << node.index();
	shared_ptr<CSGTerm> t(new CSGTerm(ps, state.matrix(), state.color(), stream.str()));
	if (modinst->isHighlight()) {
		t->flag = CSGTerm::FLAG_HIGHLIGHT;
		highlights.push_back(t);
	}
	if (modinst->isBackground()) {
		background.push_back(t);
		t.reset();
	}
	return t;
}

Response CSGTermEvaluator::visit(State &state, const AbstractPolyNode &node)
{
	if (state.isPostfix()) {
		shared_ptr<CSGTerm> t1;
		if (this->psevaluator) {
			shared_ptr<PolySet> ps = this->psevaluator->getPolySet(node, true);
			if (ps) {
				t1 = evaluate_csg_term_from_ps(state, this->highlights, this->background, 
																			 ps, node.modinst, node);
				node.progress_report();
			}
		}
		this->stored_term[node.index()] = t1;
		addToParent(state, node);
	}
	return ContinueTraversal;
}

Response CSGTermEvaluator::visit(State &state, const CsgNode &node)
{
	if (state.isPostfix()) {
		CsgOp op = CSGT_UNION;
		switch (node.type) {
		case CSG_TYPE_UNION:
			op = CSGT_UNION;
			break;
		case CSG_TYPE_DIFFERENCE:
			op = CSGT_DIFFERENCE;
			break;
		case CSG_TYPE_INTERSECTION:
			op = CSGT_INTERSECTION;
			break;
		default:
			assert(false);
		}
		applyToChildren(node, op);
		addToParent(state, node);
	}
	return ContinueTraversal;
}

Response CSGTermEvaluator::visit(State &state, const TransformNode &node)
{
	if (state.isPrefix()) {
		state.setMatrix(state.matrix() * node.matrix);
	}
	if (state.isPostfix()) {
		applyToChildren(node, CSGT_UNION);
		addToParent(state, node);
	}
	return ContinueTraversal;
}

Response CSGTermEvaluator::visit(State &state, const ColorNode &node)
{
	if (state.isPrefix()) {
		if (!state.color().isValid()) state.setColor(node.color);
	}
	if (state.isPostfix()) {
		applyToChildren(node, CSGT_UNION);
		addToParent(state, node);
	}
	return ContinueTraversal;
}

// FIXME: If we've got CGAL support, render this node as a CGAL union into a PolySet
Response CSGTermEvaluator::visit(State &state, const RenderNode &node)
{
	if (state.isPostfix()) {
		shared_ptr<CSGTerm> t1;
		shared_ptr<PolySet> ps;
		if (this->psevaluator) {
			ps = this->psevaluator->getPolySet(node, true);
			node.progress_report();
		}
		if (ps) {
			t1 = evaluate_csg_term_from_ps(state, this->highlights, this->background, 
																		 ps, node.modinst, node);
		}
		this->stored_term[node.index()] = t1;
		addToParent(state, node);
	}
	return ContinueTraversal;
}

Response CSGTermEvaluator::visit(State &state, const CgaladvNode &node)
{
	if (state.isPostfix()) {
		shared_ptr<CSGTerm> t1;
    // FIXME: Calling evaluator directly since we're not a PolyNode. Generalize this.
		shared_ptr<PolySet> ps;
		if (this->psevaluator) {
			ps = this->psevaluator->getPolySet(node, true);
		}
		if (ps) {
			t1 = evaluate_csg_term_from_ps(state, this->highlights, this->background, 
																		 ps, node.modinst, node);
			node.progress_report();
		}
		this->stored_term[node.index()] = t1;
		addToParent(state, node);
	}
	return ContinueTraversal;
}

/*!
	Adds ourself to out parent's list of traversed children.
	Call this for _every_ node which affects output during traversal.
    Usually, this should be called from the postfix stage, but for some nodes, we defer traversal letting other components (e.g. CGAL) render the subgraph, and we'll then call this from prefix and prune further traversal.
*/
void CSGTermEvaluator::addToParent(const State &state, const AbstractNode &node)
{
	this->visitedchildren.erase(node.index());
	if (state.parent()) {
		this->visitedchildren[state.parent()->index()].push_back(&node);
	}
}
