ex13_34_36_37.cpp

#include "ex12_34_36_37.h"

void swap(Message &lhs, Message &rhs)
{
    using std::swap;
    for (auto f : lhs.folders)
        f->remMsg(&lhs);
    for (auto f : rhs.folders)
        f->remMsg(&rhs);

    swap(lhs.folders, rhs.folders);
    swap(lhs.contents, rhs.contents);

    for (auto f : lhs.folders)
        f->addMsg(&lhs);
    for (auto f : rhs.folders)
        f->addMsg(&rhs);
}

// Message Implementation

void Message::save(Folder &f)
{
    folders.insert(&f);
    f.addMsg(this);
}

void Message::remove(Folder &f)
{
    folders.erase(&f);
    f.remMsg(this);
}

void Message::add_to_Folders(const Message &m)
{
    for (auto f : m.folders)
        f->addMsg(this);
}

Message::Message(const Message &m) : contents(m.contents), folders(m.folders)
{
    add_to_Folders(m);
}

void Message::remove_from_Folders()
{
    for (auto f : folders)
        f->remMsg(this);
}

Message::~Message()
{
    remove_from_Folders();
}

Message& Message::operator=(const Message &rhs)
{
    remove_from_Folders();
    contents = rhs.contents;
    folders = rhs.folders;
    add_to_Folders(rhs);
    return *this;
}

// Folder Implementation

void Folder::add_to_Message(const Folder &f)
{
    for (auto m : f.msgs)
        m->addFldr(this);
}

Folder::Folder(const Folder &f) : msgs(f.msgs)
{
    add_to_Message(f);
}

void Folder::remove_to_Message()
{
    for (auto m : msgs)
        m->remFldr(this);
}

Folder::~Folder()
{
    remove_to_Message();
}

Folder& Folder::operator =(const Folder &rhs)
{
    remove_to_Message();
    msgs = rhs.msgs;
    add_to_Message(rhs);
    return *this;
}