Chris@1648: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@1648: 
Chris@1648: /*
Chris@1648:     Sonic Visualiser
Chris@1648:     An audio file viewer and annotation editor.
Chris@1648:     Centre for Digital Music, Queen Mary, University of London.
Chris@1648:     This file copyright 2006 Chris Cannam.
Chris@1648:     
Chris@1648:     This program is free software; you can redistribute it and/or
Chris@1648:     modify it under the terms of the GNU General Public License as
Chris@1648:     published by the Free Software Foundation; either version 2 of the
Chris@1648:     License, or (at your option) any later version.  See the file
Chris@1648:     COPYING included with this distribution for more information.
Chris@1648: */
Chris@1648: 
Chris@1648: #ifndef SV_EVENT_COMMANDS_H
Chris@1648: #define SV_EVENT_COMMANDS_H
Chris@1648: 
Chris@1648: #include "base/Event.h"
Chris@1648: #include "base/Command.h"
Chris@1741: #include "base/ById.h"
Chris@1648: 
Chris@1648: /**
Chris@1648:  * Interface for classes that can be modified through these commands
Chris@1648:  */
Chris@1648: class EventEditable
Chris@1648: {
Chris@1648: public:
Chris@1648:     virtual void add(Event e) = 0;
Chris@1648:     virtual void remove(Event e) = 0;
Chris@1648: };
Chris@1648: 
Chris@1741: template <typename Base>
Chris@1741: class WithEditable
Chris@1741: {
Chris@1741:     typedef typename Base::Id Id;
Chris@1741:     Id m_id;
Chris@1741:     
Chris@1741: protected:
Chris@1741:     WithEditable(Id id) : m_id(id) { }
Chris@1741: 
Chris@1741:     std::shared_ptr<EventEditable> getEditable() {
Chris@1741:         auto base = StaticById<Base, Id>::get(m_id);
Chris@1741:         if (!base) return {}; // acceptable - item has expired
Chris@1741:         auto editable = std::dynamic_pointer_cast<EventEditable>(base);
Chris@1741:         if (!editable) {
Chris@1741:             SVCERR << "WARNING: Id passed to EventEditable command is not that of an EventEditable" << endl;
Chris@1741:         }
Chris@1741:         return editable;
Chris@1741:     }
Chris@1741: };
Chris@1741: 
Chris@1648: /**
Chris@1741:  * Command to add an event to an editable containing events, with
Chris@1741:  * undo.  The template parameter must be a type that can be
Chris@1741:  * dynamic_cast to EventEditable and that has a ById store.
Chris@1648:  */
Chris@1741: template <typename Base>
Chris@1741: class AddEventCommand : public Command,
Chris@1741:                         public WithEditable<Base>
Chris@1648: {
Chris@1648: public:
Chris@1741:     AddEventCommand(typename Base::Id editable, const Event &e, QString name) :
Chris@1741:         WithEditable<Base>(editable), m_event(e), m_name(name) { }
Chris@1648: 
Chris@1648:     QString getName() const override { return m_name; }
Chris@1648:     Event getEvent() const { return m_event; }
Chris@1648: 
Chris@1741:     void execute() override {
Chris@1741:         auto editable = getEditable();
Chris@1741:         if (editable) editable->add(m_event);
Chris@1741:     }
Chris@1741:     void unexecute() override {
Chris@1741:         auto editable = getEditable();
Chris@1741:         if (editable) editable->remove(m_event);
Chris@1741:     }
Chris@1648: 
Chris@1648: private:
Chris@1648:     Event m_event;
Chris@1648:     QString m_name;
Chris@1741:     using WithEditable<Base>::getEditable;
Chris@1648: };
Chris@1648: 
Chris@1648: /**
Chris@1648:  * Command to remove an event from an editable containing events, with
Chris@1741:  * undo.  The template parameter must be a type that implements
Chris@1741:  * EventBase and that has a ById store.
Chris@1648:  */
Chris@1741: template <typename Base>
Chris@1741: class RemoveEventCommand : public Command,
Chris@1741:                            public WithEditable<Base>
Chris@1648: {
Chris@1648: public:
Chris@1741:     RemoveEventCommand(typename Base::Id editable, const Event &e, QString name) :
Chris@1741:         WithEditable<Base>(editable), m_event(e), m_name(name) { }
Chris@1648: 
Chris@1648:     QString getName() const override { return m_name; }
Chris@1648:     Event getEvent() const { return m_event; }
Chris@1648: 
Chris@1741:     void execute() override {
Chris@1741:         auto editable = getEditable();
Chris@1741:         if (editable) editable->remove(m_event);
Chris@1741:     }
Chris@1741:     void unexecute() override {
Chris@1741:         auto editable = getEditable();
Chris@1741:         if (editable) editable->add(m_event);
Chris@1741:     }
Chris@1648: 
Chris@1648: private:
Chris@1648:     Event m_event;
Chris@1648:     QString m_name;
Chris@1741:     using WithEditable<Base>::getEditable;
Chris@1648: };
Chris@1648: 
Chris@1648: /**
Chris@1648:  * Command to add or remove a series of events to or from an editable,
Chris@1648:  * with undo. Creates and immediately executes a sub-command for each
Chris@1648:  * add/remove requested. Consecutive add/remove pairs for the same
Chris@1741:  * point are collapsed.  The template parameter must be a type that
Chris@1741:  * implements EventBase and that has a ById store.
Chris@1648:  */
Chris@1741: template <typename Base>
Chris@1648: class ChangeEventsCommand : public MacroCommand
Chris@1648: {
Chris@1741:     typedef typename Base::Id Id;
Chris@1741:     
Chris@1648: public:
Chris@1741:     ChangeEventsCommand(Id editable, QString name) :
Chris@1648:         MacroCommand(name), m_editable(editable) { }
Chris@1648: 
Chris@1648:     void add(Event e) {
Chris@1741:         addCommand(new AddEventCommand<Base>(m_editable, e, getName()),
Chris@1741:                    true);
Chris@1648:     }
Chris@1648:     void remove(Event e) {
Chris@1741:         addCommand(new RemoveEventCommand<Base>(m_editable, e, getName()),
Chris@1741:                    true);
Chris@1648:     }
Chris@1648: 
Chris@1648:     /**
Chris@1648:      * Stack an arbitrary other command in the same sequence.
Chris@1648:      */
Chris@1648:     void addCommand(Command *command) override { addCommand(command, true); }
Chris@1648: 
Chris@1648:     /**
Chris@1648:      * If any points have been added or deleted, return this
Chris@1648:      * command (so the caller can add it to the command history).
Chris@1648:      * Otherwise delete the command and return NULL.
Chris@1648:      */
Chris@1648:     ChangeEventsCommand *finish() {
Chris@1648:         if (!m_commands.empty()) {
Chris@1648:             return this;
Chris@1648:         } else {
Chris@1648:             delete this;
Chris@1648:             return nullptr;
Chris@1648:         }
Chris@1648:     }
Chris@1648: 
Chris@1648: protected:
Chris@1648:     virtual void addCommand(Command *command, bool executeFirst) {
Chris@1648:         
Chris@1648:         if (executeFirst) command->execute();
Chris@1648: 
Chris@1648:         if (m_commands.empty()) {
Chris@1648:             MacroCommand::addCommand(command);
Chris@1648:             return;
Chris@1648:         }
Chris@1648:         
Chris@1741:         RemoveEventCommand<Base> *r =
Chris@1741:             dynamic_cast<RemoveEventCommand<Base> *>(command);
Chris@1741:         AddEventCommand<Base> *a =
Chris@1741:             dynamic_cast<AddEventCommand<Base> *>(*m_commands.rbegin());
Chris@1648:         if (r && a) {
Chris@1648:             if (a->getEvent() == r->getEvent()) {
Chris@1648:                 deleteCommand(a);
Chris@1648:                 return;
Chris@1648:             }
Chris@1648:         }
Chris@1648:         
Chris@1648:         MacroCommand::addCommand(command);
Chris@1648:     }
Chris@1648: 
Chris@1741:     Id m_editable;
Chris@1648: };
Chris@1648: 
Chris@1648: #endif