/**
* Check the dependencies (recursively) of this content info
* @param ci the content info to check the dependencies of
*/
void ClientNetworkContentSocketHandler::CheckDependencyState(ContentInfo *ci)
{
if (ci->IsSelected() || ci->state == ContentInfo::ALREADY_HERE) {
/* Selection is easy; just walk all children and set the
* autoselected state. That way we can see what we automatically
* selected and thus can unselect when a dependency is removed. */
for (uint i = 0; i < ci->dependency_count; i++) {
ContentInfo *c = this->GetContent(ci->dependencies[i]);
if (c == NULL) {
this->DownloadContentInfo(ci->dependencies[i]);
} else if (c->state == ContentInfo::UNSELECTED) {
c->state = ContentInfo::AUTOSELECTED;
this->CheckDependencyState(c);
}
}
return;
}
if (ci->state != ContentInfo::UNSELECTED) return;
/* For unselection we need to find the parents of us. We need to
* unselect them. After that we unselect all children that we
* depend on and are not used as dependency for us, but only when
* we automatically selected them. */
ConstContentVector parents;
this->ReverseLookupDependency(parents, ci);
for (ConstContentIterator iter = parents.Begin(); iter != parents.End(); iter++) {
const ContentInfo *c = *iter;
if (!c->IsSelected()) continue;
this->Unselect(c->id);
}
for (uint i = 0; i < ci->dependency_count; i++) {
const ContentInfo *c = this->GetContent(ci->dependencies[i]);
if (c == NULL) {
DownloadContentInfo(ci->dependencies[i]);
continue;
}
if (c->state != ContentInfo::AUTOSELECTED) continue;
/* Only unselect when WE are the only parent. */
parents.Clear();
this->ReverseLookupDependency(parents, c);
/* First check whether anything depends on us */
int sel_count = 0;
bool force_selection = false;
for (ConstContentIterator iter = parents.Begin(); iter != parents.End(); iter++) {
if ((*iter)->IsSelected()) sel_count++;
if ((*iter)->state == ContentInfo::SELECTED) force_selection = true;
}
if (sel_count == 0) {
/* Nothing depends on us */
this->Unselect(c->id);
continue;
}
/* Something manually selected depends directly on us */
if (force_selection) continue;
/* "Flood" search to find all items in the dependency graph*/
parents.Clear();
this->ReverseLookupTreeDependency(parents, c);
/* Is there anything that is "force" selected?, if so... we're done. */
for (ConstContentIterator iter = parents.Begin(); iter != parents.End(); iter++) {
if ((*iter)->state != ContentInfo::SELECTED) continue;
force_selection = true;
break;
}
/* So something depended directly on us */
if (force_selection) continue;
/* Nothing depends on us, mark the whole graph as unselected.
* After that's done run over them once again to test their children
* to unselect. Don't do it immediatelly because it'll do exactly what
* we're doing now. */
for (ConstContentIterator iter = parents.Begin(); iter != parents.End(); iter++) {
const ContentInfo *c = *iter;
if (c->state == ContentInfo::AUTOSELECTED) this->Unselect(c->id);
}
for (ConstContentIterator iter = parents.Begin(); iter != parents.End(); iter++) {
this->CheckDependencyState(this->GetContent((*iter)->id));
}
}
}
