Make parallel lines

And make TODO for P2P

Canvas.cpp

@@ -1,21 +1,43 @@
 #include "Canvas.h"
+
 void Canvas::changeMode(Mode _mode)
 {
 	mode = _mode;
 }
 
+// TODO
+Line* Canvas::findAt(QPointF& pos)
+{
+	for (Line* line : lines) {
+		if (line->contains(pos)) {
+			return line;
+		}
+	}
+	return nullptr;
+}
+
+LinePair Canvas::makeOrderedPair(Line* l1, Line* l2)
+{
+	return (l1 < l2) ? std::make_pair(l1, l2) : std::make_pair(l2, l1);
+}
+
+bool Canvas::areAlreadyParallel(Line* l1, Line* l2)
+{
+	return parallelPairs.count(makeOrderedPair(l1, l2)) > 0;
+}
+
 void Canvas::mousePressEvent(QMouseEvent* event)
 {
 	QPointF scene = event->pos();
 
-#ifdef _DEBUG
-	qDebug() << "Scene point in" << scene.x() << scene.y();
-	changeMode(DrawingLine);
-#endif
+	#ifdef _DEBUG
+		qDebug() << "Scene point in" << scene.x() << scene.y();
+	#endif
 	
-	if (mode == DrawingLine) {
+	if (mode == Mode::DrawingLine) {
 		if (!current_line) {
 			current_line = new Line();
+			current_line->set_tag(obj_count);
 			double* x1 = new double(scene.x());
 			double* y1 = new double(scene.y());
 
@@ -25,6 +47,9 @@ void Canvas::mousePressEvent(QMouseEvent* event)
 			params.push_back(x1);
 			params.push_back(y1);
 
+			points.push_back(Point(x1, y1, obj_count));
+			points.push_back(Point(x2, y2, obj_count));
+
 			current_line->p1.x = x1;
 			current_line->p1.y = y1;
 			current_line->p2.x = x2;
@@ -39,25 +64,83 @@ void Canvas::mousePressEvent(QMouseEvent* event)
 
 			lines.append(current_line);
 			current_line = nullptr;
-		}
-
-//#ifdef _DEBUG
-//		if (lines.size()) {
-//			qDebug() << "Line coords" << lines[lines.size() - 1]->p1.get_X() <<
-//				lines[lines.size() - 1]->p1.get_Y() <<
-//				lines[lines.size() - 1]->p2.get_X() <<
-//				lines[lines.size() - 1]->p2.get_Y();
-//			changeMode(None);
-//		}
-//#endif		
-
+			mode = Mode::None;
+			obj_count++;
+			update();
+			return;
+		}	
 	}
 
+	else if (mode == Mode::Parallel) {
+		static Line* first = nullptr;
+		Line* found = findAt(scene);
+
+		if (!found) {
+			first = nullptr;
+			return;
+		}
+
+		if (!first) {
+			first = found;
+			return;
+		}
+
+		if (found == first){
+			first = nullptr;
+			return;
+		}
+
+		if (!areAlreadyParallel(found, first)) {
+			sys.addConstraintParallel(*found, *first, constraints_count++);
+			parallelPairs.insert(makeOrderedPair(found, first));
+			first = nullptr;
+			mode = Mode::None;
+		}
+
+		else {
+			
+		#ifdef _DEBUG
+			qDebug() << "Line" << first << "and" << found << "are parallel. Abort!";
+		#endif
+			QMessageBox::information(this,
+				QString("Wrong"),
+				QString("Parallel lines can not be more parallel!"),
+				QMessageBox::Ok
+			);
+			first = nullptr;
+			return;
+		}
+
+		update();
+	}
+}
+
+void Canvas::paintEvent(QPaintEvent*)
+{
+	QPainter p(this);
+	p.setRenderHint(QPainter::Antialiasing);
+	if (!params.empty()) {
+		int res = sys.solve(params);
+		if (res == SolveStatus::Success) {
+			sys.applySolution();
+		}
+		else {
+		#ifdef _DEBUG
+			qDebug() << "INVAILD LAST CONSTRAINT. REMOVE HIM";
+		#endif
+			sys.removeConstraint(sys.get_last_constraint());
+		}
+	}
+	for (Line* line : lines) {
+		line->draw(p);
+	}
+	return;
 }
 
 Canvas::Canvas(QWidget *parent)
 	: QWidget(parent)
 {
+	sys = System();
 	current_line = nullptr;
 	setMouseTracking(true);
 	setBackgroundRole(QPalette::Base);
@@ -76,6 +159,7 @@ Canvas::~Canvas()
 
 	lines.clear();
 	params.clear();
+	points.clear();
 
 	if (current_line) 
 		delete current_line;