Implementation for Structogram iterator and Statement type

The interator is not (yet) aware of the scope in which it is iterating.

4 files changed, 199 insertions, 24 deletions

diff --git a/src/diagram/Statement.cpp b/src/diagram/Statement.cpp
index 75770db..60be094 100644
--- a/src/diagram/Statement.cpp
+++ b/src/diagram/Statement.cpp
@@ -5,8 +5,21 @@
  *      Author: naopross
  */
 
-#include "../diagram/Statement.h"
+#include "Statement.hpp"
 
 namespace samb {
 
+Statement::pointer Statement::makeStatement(Statement::Type t) {
+	return std::make_shared<Statement>(Statement(t, "", nullptr, nullptr));
+}
+
+bool Statement::operator==(const Statement& other) {
+	return (this->type == other.type) && (this->text == other.text) &&
+			(this->next == other.next) && (this->scope == other.scope);
+}
+
+
+Statement::Statement(Type t, std::string txt, Statement::pointer p, Statement::pointer s): type(t), text(txt), next(p), scope(s) {}
+Statement::~Statement() {}
+
 } /* namespace samb */
diff --git a/src/diagram/Statement.hpp b/src/diagram/Statement.hpp
index a90e88d..8c41714 100644
--- a/src/diagram/Statement.hpp
+++ b/src/diagram/Statement.hpp
@@ -9,6 +9,7 @@
 #define SRC_STATEMENT_H_
 
 #include <string>
+#include <memory>
 
 namespace samb {
 
@@ -24,24 +25,23 @@ namespace samb {
  * PARALLEL,
  */
 
-/* this class should behave like a std::list,  or a std::map storing the data
- * with a tree structure, BUT it is not a tree because allows 2 notes to point
+/* this struct is a link for linked list that stores the data in a tree-like
+ * structure, BUT it is not a tree because it allows 2 or more nodes to point
  * at a single node
  *
- * Normal Tree:          Statements:
+ * Tree:                 Statements:
  * A - B - C - D         A - B - C - D - G
  *     \                     \      /
  *      E - F                 E - F
  *
- * Because a statement contains branching elmeents. (if / switch)
+ * Because a statements can be branching elements. (if / switch)
+ *
+ * This class is also a *Factory* to make statements.
  */
-class Statement {
-private:
-	Statement *next;
-	Statement *prev;
+struct Statement {
+	using pointer = std::shared_ptr<Statement>;
 
-public:
-	const enum Type {
+	enum Type {
 		PROCESS,
 		DECISION,
 		SWITCH,
@@ -49,10 +49,30 @@ public:
 		UNTIL,
 		SCOPE,
 		PARALLEL,
-	} m_type;
 
-	Statement(Type type, Statement *prev): m_type(type), m_prev(prev);
+		/* this type of statement indicates the end of the program
+		 * and it is used only internally
+		 *
+		 * TODO: think of something more elegant to solve this
+		 */
+		END
+	} type;
+
+	std::string text;
+
+	pointer next;
+	pointer scope; // TODO: make iterator look for this
+
+	static Statement::pointer makeStatement(Type t);
+//	static Statement::pointer makeProcess();
+//	static Statement::pointer makeLoop(Type t, std::string condition);
+//	static Statement::pointer makeBranching(Type t, std::string condition);
+
 	virtual ~Statement();
+	bool operator==(const Statement& other);
+
+private:
+	Statement(Type type, std::string txt, pointer next, pointer scope);
 };
 
 } /* namespace samb */
diff --git a/src/diagram/Structogram.cpp b/src/diagram/Structogram.cpp
index dae9028..a21c62d 100644
--- a/src/diagram/Structogram.cpp
+++ b/src/diagram/Structogram.cpp
@@ -5,23 +5,126 @@
  *      Author: naopross
  */
 
-#include "../diagram/Structogram.h"
+#include "../diagram/Structogram.hpp"
 #include <memory>
+#include <exception>
 
 
 namespace samb {
 
-Structogram::Structogram(std::string title): m_title(title) {
+/* iterator nested class */
+Structogram::iterator::iterator(Statement::pointer first) {
+	m_current = first;
+}
+
+Structogram::iterator::~iterator() {}
+
+Structogram::iterator& Structogram::iterator::operator++() {
+	if (m_current->next != nullptr) {
+		m_current = m_current->next;
+	}
+
+	return *this;
+}
+
+Structogram::iterator& Structogram::iterator::operator++(int) {
+	static iterator old(*this);
+	old = *this;
+
+	operator++();
+	return old;
+}
+
+bool Structogram::iterator::operator==(const iterator& other) const {
+	if (*this->m_current == *other.m_current) {
+		return true;
+	}
+
+	return false;
+}
+
+bool Structogram::iterator::operator!=(const iterator& other) const {
+	return !(other == *this);
+}
+
+Statement& Structogram::iterator::operator*() const {
+	if (m_current == nullptr) {
+		throw std::logic_error("structogram iterator: m_current is nullptr");
+	}
+
+	return *m_current;
+}
+
+Statement::pointer Structogram::iterator::operator->() const {
+	return m_current;
+}
+
 
+/**
+ *  Structogram class methods
+ */
+Structogram::Structogram(std::string title) {
+
+	m_size = 0;
+	m_title = title;
+
+	m_head = Statement::makeStatement(Statement::Type::SCOPE);
+	m_tail = Statement::makeStatement(Statement::Type::END);
+
+	m_head->next = m_tail;
+	m_head->text = m_title;
 }
 
 Structogram::~Structogram() {
+	/* no need to destroy anything because of smart pointers */
+}
 
+std::size_t Structogram::size() const {
+	return m_size;
 }
 
-const std::list<Statement>& Structogram::getStatements() const {
-	return m_statements;
+Structogram::iterator Structogram::insert_after(Structogram::iterator it, Statement::pointer statement) {
+
+	if (statement == nullptr) {
+		throw std::invalid_argument("structogram: attempt to insert a null statement");
+	}
+
+	statement->next = it->next;
+	it->next = statement;
+	m_size++;
+
+	return ++it;
 }
 
+//Structogram::iterator Structogram::insert_after(Structogram::iterator it, Statement::pointer statement) {
+//	return insert(++it, statement);
+//}
+
+Structogram::iterator Structogram::erase_after(iterator it) {
+
+	// TODO: error handling IE return a std::pair<iterator, bool>
+
+	/* the first statement (scope of the program) cannot be deleted */
+	if ((*it) == *m_head) {
+		return it;
+	}
+
+	if (it->next == nullptr) {
+		return it;
+	}
+
+	it->next = it->next->next;
+
+	return it;
+}
+
+/* iterator related methods */
+Structogram::iterator Structogram::begin() const {
+	return iterator(m_head);
+}
+
+const Structogram::iterator Structogram::end() const {
+	return iterator(m_tail);
+}
 
 } /* namespace structograms */
diff --git a/src/diagram/Structogram.hpp b/src/diagram/Structogram.hpp
index 2234142..9318ee4 100644
--- a/src/diagram/Structogram.hpp
+++ b/src/diagram/Structogram.hpp
@@ -10,21 +10,60 @@
 
 #include <iostream>
 #include <list>
-#include "../diagram/Statement.h"
+
+#include "Statement.hpp"
 
 namespace samb {
 
-/* object that holds statements */
+/* A Structogram is a Nassi-Schneiderman diagram, in this implementation it is
+ * simply and iterable object that holds statements.
+ *
+ * The first statement inside a structogram (m_head) is a SCOPE
+ * statement that holds the entire program inside it.
+ */
 class Structogram {
-private:
-	std::list<Statement> m_statements;
-	std::string m_title;
-
 public:
+	/* forward only iterator */
+	class iterator {
+	public:
+		iterator(Statement::pointer first);
+		~iterator();
+
+		iterator& operator++();
+		iterator& operator++(int);
+
+		bool operator==(const iterator& other) const;
+		bool operator!=(const iterator& other) const;
+		Statement& operator*() const;
+		Statement::pointer operator->() const;
+
+	private:
+		Statement::pointer m_current;
+	};
+
 	Structogram(std::string title);
 	virtual ~Structogram();
 
-	const std::list<Statement>& getStatements() const;
+	std::size_t size() const;
+
+	// cannot be implemented because iter is forward only
+//	iterator insert(iterator it, Statement::pointer statement);
+//	iterator erase(iterator it);
+
+	iterator insert_after(iterator it, Statement::pointer statement);
+	iterator erase_after(iterator it);
+
+	/* iterator */
+	iterator begin() const;
+	const iterator end() const;
+	const Statement& operator[](const Statement& it) = delete;
+
+private:
+	std::size_t m_size;
+	std::string m_title;
+
+	Statement::pointer m_head;
+	Statement::pointer m_tail;
 };
 
 } /* namespace structograms */