LUMIERA.clone/src/proc/mobject/session/scope-path.cpp

348 lines
9 KiB
C++

/*
ScopePath - logical access path down from Session root
Copyright (C) Lumiera.org
2009, Hermann Vosseler <Ichthyostega@web.de>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
* *****************************************************/
/** @file scope-path.cpp
** @todo WIP implementation of session core from 2010
** @todo as of 2016, this effort is considered stalled but basically valid
*/
#include "include/logging.h"
#include "proc/mobject/session/scope-path.hpp"
#include "proc/mobject/session/scope-locator.hpp"
#include "proc/mobject/session/session-service-explore-scope.hpp"
#include "proc/mobject/mobject.hpp"
#include "lib/itertools.hpp"
#include "lib/symbol.hpp"
#include "lib/error.hpp"
#include "lib/util.hpp"
#include <algorithm>
namespace proc {
namespace mobject {
namespace session {
using std::reverse;
using lib::append_all;
using util::isSameObject;
using util::isnil;
LUMIERA_ERROR_DEFINE (EMPTY_SCOPE_PATH, "Placement scope not locatable (empty model path)");
namespace { // Helpers and shortcuts....
/** issue a query to discover the (raw) path to root,
* starting with the given scope */
inline ScopeQuery<MObject>::iterator
discoverScopePath (Scope const& leaf)
{
return ScopeLocator::instance().getRawPath (leaf);
}
void
___check_notBottom (const ScopePath *path, lib::Literal operation_descr)
{
REQUIRE (path);
if (path->empty())
throw error::Logic (operation_descr+" an empty placement scope path"
, LERR_(EMPTY_SCOPE_PATH));
}
}//(End) helpers
/**
* Create an \em empty path.
* By default, a scope path just contains
* the root scope of the current session (PlacementIndex).
* @note invoking this function accesses the session and thus
* may cause an empty default session to be created.
*/
ScopePath::ScopePath ()
: refcount_(0)
, path_()
{
clear();
}
/**
* When creating a path to a given (leaf) scope,
* the complete sequence of nested scopes leading to
* this special scope is discovered, using the query service
* exposed by the session (through ScopeLocator).
* @note when locating the default (invalid) scope,
* a special empty ScopePath is created
* @throw error::Invalid if the given target scope
* can't be connected to the (implicit) root
*/
ScopePath::ScopePath (Scope const& leaf)
: refcount_(0)
, path_()
{
if (leaf == Scope::INVALID) return; // invalid leaf defines invalid path....
clear();
navigate (leaf);
}
ScopePath::ScopePath (ScopePath const& o)
: refcount_(0)
, path_(o.path_)
{ }
/**
* Copy from existing path
* @throw error::Logic when current path has nonzero refcount
*/
ScopePath&
ScopePath::operator= (ScopePath const& ref)
{
if (0 < refcount_)
throw error::Logic ("Attempt to overwrite a ScopePath with nonzero refcount");
if (!isSameObject (*this, ref))
{
path_ = ref.path_;
ENSURE (0 == refcount_);
}
return *this;
}
ScopePath::~ScopePath()
{
WARN_IF (refcount_, session, "Destroying a scope path frame with ref-count=%zu", refcount_);
}
/** constant \em invalid path token. Created by locating an invalid scope */
const ScopePath ScopePath::INVALID = ScopePath(Scope());
/** ScopePath diagnostic self display.
* Implemented similar to a filesystem path, where the
* path elements are based on the self-display of the MObject
* attached through the respective scope top placement. */
ScopePath::operator string() const
{
if (isnil (path_)) return "!";
if (1 == length()) return "/";
string res;
vector<Scope>::const_iterator node (path_.begin());
while (++node != path_.end())
{
res += "/";
res += string (*node);
}
return res;
}
/** a \em valid path consists of more than just the root element.
* @note contrary to this, an \em empty path doesn't even contain a root element
*/
bool
ScopePath::isValid() const
{
return (1 < length())
#if NOBUG_MODE_ALPHA
&& hasValidRoot()
#endif
;
}
bool
ScopePath::hasValidRoot() const
{
REQUIRE (0 < length());
return path_[0] == currModelRoot();
}
PlacementMO const&
ScopePath::currModelRoot() const
{
return SessionServiceExploreScope::getScopeRoot();
}
/* == Relations == */
Scope const&
ScopePath::getLeaf() const
{
___check_notBottom (this, "Inspecting");
return path_.back();
}
/** verify the scope in question is equivalent
* to our leaf scope. Equivalence of scopes means
* they are defined by the same scope top placement,
* i.e. registered with the same Placement-ID.
*/
bool
ScopePath::endsAt(Scope const& aScope) const
{
return aScope == getLeaf();
}
bool
ScopePath::contains (Scope const& aScope) const
{
if (aScope == Scope::INVALID) return true; // bottom is contained everywhere
for (iterator ii = this->begin(); ii; ++ii)
if (aScope == *ii)
return true;
return false;
}
bool
ScopePath::contains (ScopePath const& otherPath) const
{
if (!otherPath.isValid()) return true;
if ( empty()) return false;
if (!isValid()) return false;
ASSERT (1 < length());
ASSERT (1 < otherPath.length());
for (iterator ii = otherPath.begin(); ii; ++ii)
if (!this->contains (*ii))
return false;
return true;
}
ScopePath
commonPrefix (ScopePath const& path1, ScopePath const& path2)
{
ScopePath prefix (ScopePath::INVALID);
uint len = std::min (path1.length(), path2.length());
for (uint pos = 0; pos<len; ++pos)
if (path1.path_[pos] == path2.path_[pos])
prefix.appendScope (path1.path_[pos]);
return prefix;
}
bool
disjoint (ScopePath const& path1, ScopePath const& path2)
{
if (path1.empty() || path2.empty()) return false;
return (path1.isValid() && path2.isValid())
&& (path1.path_[1] != path2.path_[1]) // no common prefix
;
}
/* == Mutations == */
void
ScopePath::clear()
{
path_.clear();
path_.push_back (currModelRoot());
ENSURE (!empty());
ENSURE (!isValid());
ENSURE ( hasValidRoot());
}
Scope const&
ScopePath::moveUp()
{
___check_notBottom (this, "Navigating");
path_.resize (length()-1);
if (empty()) return Scope::INVALID;
else return path_.back();
}
Scope const&
ScopePath::goRoot()
{
___check_notBottom (this, "Navigating");
ENSURE (hasValidRoot());
path_.resize (1);
return path_.back();
}
void
ScopePath::navigate (Scope const& target)
{
___check_notBottom (this, "Navigating");
if (!target.isValid())
throw error::Invalid ("can't navigate to a target scope outside the model"
, LERR_(INVALID_SCOPE));
std::vector<Scope> otherPath;
append_all (discoverScopePath(target), otherPath);
reverse (otherPath.begin(), otherPath.end());
////////////////////////////TICKET #663 extension point for meta-clip support
ASSERT (path_[0] == otherPath[0]); // sharing the root element
this->path_ = otherPath; // TODO really relate the two paths, including a treatment for meta-clips
// - if both are in the same sequence (same head element): just attach the tail of the other
// - if the other path points into a sequence which is attached as meta-clip to the current sequence,
// then attach the other path below that meta-clip (problem: resolve multiple attachments)
// - otherwise use the first timeline, to which the other path's sequence is attached
// - otherwise, if all else fails, use the raw otherPath
} ////////////////////////////////////TICKET #672
void
ScopePath::appendScope (Scope const& child) ///< @internal backdoor for #commonPrefix
{
path_.push_back (child);
}
}}} // namespace mobject::session