#ifndef MSP_DATAFILE_COLLECTION_H_
#define MSP_DATAFILE_COLLECTION_H_
+#include <type_traits>
+#include <msp/core/attributes.h>
#include <msp/core/maputils.h>
-#include <msp/core/meta.h>
+#include <msp/core/noncopyable.h>
#include <msp/core/refptr.h>
#include "collectionsource.h"
#include "loader.h"
+#include "meta.h"
/* XXX This file is a big mess with too many things in it. However, the
dependencies between those things make it difficult to split up. */
namespace Msp {
namespace DataFile {
-/**
-Helper struct to determine whether a Loader has a Collection typedef.
-*/
+class CollectionItemTypeBase;
+
template<typename T>
-struct NeedsCollection
-{
- struct Yes { char c[2]; };
- struct No { char c; };
+class CollectionItemType;
- template<typename U>
- static Yes f(typename U::Collection *);
- template<typename U>
- static No f(...);
+template<typename T>
+class LoadableCollectionItemType;
- enum { value = (sizeof(f<T>(0))==sizeof(Yes)) };
-};
+template<typename T, bool = HasLoader<T>::value>
+struct CollectionItemTypeChooser;
-class CollectionItemTypeBase;
+template<typename T>
+struct CollectionItemTypeChooser<T, true>
+{ typedef LoadableCollectionItemType<T> Type; };
template<typename T>
-class CollectionItemType;
+struct CollectionItemTypeChooser<T, false>
+{ typedef CollectionItemType<T> Type; };
/**
A collection of objects that can be loaded from a datafile. Each object is
Collections can have sources for loading objects on demand. Automatic loading
only works on a non-const Collection. See class CollectionSource for details.
+
+As a last resort, a fallback collection can be designated for loading items
+that are not present. Items retrieted from the fallback collection are shared
+between the collections, and are only deleted when all collections in the chain
+have been destroyed.
*/
-class Collection
+class Collection: private NonCopyable
{
public:
/**
*/
class Loader: public DataFile::Loader
{
- template<typename T> friend class CollectionItemType;
+ template<typename T> friend class LoadableCollectionItemType;
private:
Collection &coll;
private:
typedef std::map<std::string, Variant> ItemMap;
- typedef std::list<CollectionItemTypeBase *> TypeList;
- typedef std::list<CollectionSource *> SourceList;
- TypeList types;
+ std::vector<CollectionItemTypeBase *> types;
ItemMap items;
- SourceList sources;
+ std::vector<const CollectionSource *> sources;
+ Collection *fallback;
- Collection(const Collection &);
- Collection &operator=(const Collection &);
public:
- Collection() { }
+ Collection();
virtual ~Collection();
/** Adds an object into the collection. The name must not pre-exist. The
if(!item)
throw std::invalid_argument("Collection::add(item)");
- RefPtr<typename RemoveConst<T>::Type> ptr(item);
+ typedef typename std::remove_cv<T>::type NCT;
+ RefPtr<NCT> ptr(item);
try
{
- insert_unique(items, name, ptr);
+ add_var(name, get_type<NCT>(name), ptr);
}
catch(...)
{
template<typename T>
T &get(const std::string &name) const
{
- return extract<typename RemoveConst<T>::Type>(get_item(items, name));
+ return extract<typename std::remove_cv<T>::type>(get_item(items, name));
}
/** Gets a typed object from the collection. If the name is not found,
template<typename T>
T &get(const std::string &name)
{
- typedef typename RemoveConst<T>::Type NCT;
- return extract<NCT>(get_var(name, get_type<NCT>()));
+ typedef typename std::remove_cv<T>::type NCT;
+ return extract<NCT>(get_var(name, get_type<NCT>(name)));
+ }
+
+ /** Finds a typed object in the collection. Returns null if the name does
+ not exist. Throws if the name exists but the object is of an incorrect
+ type. */
+ template<typename T>
+ T *find(const std::string &name) const
+ {
+ ItemMap::const_iterator i = items.find(name);
+ return (i!=items.end() ? extract<typename std::remove_cv<T>::type>(i->second) : 0);
+ }
+
+ template<typename T>
+ T *find(const std::string &name)
+ {
+ typedef typename std::remove_cv<T>::type NCT;
+ const Variant *var = find_var(name, get_type<NCT>(name));
+ return (var ? &extract<NCT>(*var) : 0);
}
private:
+ void add_var(const std::string &, const CollectionItemTypeBase *, const Variant &);
const Variant &get_var(const std::string &, const CollectionItemTypeBase *);
+ const Variant *find_var(const std::string &, const CollectionItemTypeBase *);
template<typename T>
T &extract(const Variant &var) const;
template<typename T>
- std::list<T *> extract_list(const std::list<const Variant *> &vars) const
+ std::list<T *> extract_list(const std::vector<const Variant *> &vars) const
{
std::list<T *> result;
- for(std::list<const Variant *>::const_iterator i=vars.begin(); i!=vars.end(); ++i)
- result.push_back(&extract<T>(**i));
+ for(const Variant *v: vars)
+ result.push_back(&extract<T>(*v));
return result;
}
- void gather_items(std::list<const Variant *> *, std::list<std::string> *, const CollectionItemTypeBase &, bool) const;
+ void gather_items(std::vector<const Variant *> *, std::list<std::string> *, const CollectionItemTypeBase &, bool) const;
template<typename T>
- void gather_items(std::list<const Variant *> *vars, std::list<std::string> *names, const CollectionItemTypeBase *type, bool include_sources) const
+ void gather_items(std::vector<const Variant *> *vars, std::list<std::string> *names, const CollectionItemTypeBase *type, bool include_sources) const
{
if(type || (type = get_type<T>()))
gather_items(vars, names, *type, include_sources);
std::list<std::string> get_names() const
{
std::list<std::string> names;
- gather_items<typename RemoveConst<T>::Type>(0, &names, 0, false);
+ gather_items<typename std::remove_cv<T>::type>(0, &names, 0, false);
return names;
}
std::list<std::string> get_names()
{
std::list<std::string> names;
- gather_items<typename RemoveConst<T>::Type>(0, &names, 0, true);
+ gather_items<typename std::remove_cv<T>::type>(0, &names, 0, true);
return names;
}
template<typename T>
std::list<T *> get_list() const
{
- std::list<const Variant *> vars;
- gather_items<typename RemoveConst<T>::Type>(&vars, 0, 0, false);
+ std::vector<const Variant *> vars;
+ gather_items<typename std::remove_cv<T>::type>(&vars, 0, 0, false);
return extract_list<T>(vars);
}
template<typename T>
std::list<T *> get_list()
{
- CollectionItemTypeBase *type = get_type<typename RemoveConst<T>::Type>();
+ CollectionItemTypeBase *type = get_type<typename std::remove_cv<T>::type>();
if(type)
load_items_from_sources(*type);
- std::list<const Variant *> vars;
- gather_items<typename RemoveConst<T>::Type>(&vars, 0, type, true);
+ std::vector<const Variant *> vars;
+ gather_items<typename std::remove_cv<T>::type>(&vars, 0, type, true);
return extract_list<T>(vars);
}
/// Checks whether a typed object exists in the collection.
template<typename T>
bool contains(const std::string &name) const
- { return get_status<typename RemoveConst<T>::Type>(name)==1; }
+ { return get_status<typename std::remove_cv<T>::type>(name)==1; }
/** Checks whether a typed object exists in the collection or is loadable
from a source. */
template<typename T>
bool contains(const std::string &name)
- { return get_status<typename RemoveConst<T>::Type>(name)>0; }
+ { return get_status<typename std::remove_cv<T>::type>(name)>0; }
/// Returns the name of an item in the collection.
template<typename T>
const std::string &get_name(T *d) const
{
- typedef RefPtr<typename RemoveConst<T>::Type> RPNCT;
+ typedef RefPtr<typename std::remove_cv<T>::type> RPNCT;
- for(ItemMap::const_iterator i=items.begin(); i!=items.end(); ++i)
- if(i->second.check_type<RPNCT>())
- if(i->second.value<RPNCT>().get()==d)
- return i->first;
+ for(const auto &kvp: items)
+ if(kvp.second.check_type<RPNCT>())
+ if(kvp.second.value<RPNCT>().get()==d)
+ return kvp.first;
// XXX Need better exception class
throw std::runtime_error("Item not found in collection");
/** Adds a type to the collection. The returned descriptor object reference
can be used to define how objects of that type can be loaded. */
template<typename T>
- CollectionItemType<T> &add_type();
+ typename CollectionItemTypeChooser<T>::Type &add_type();
+
+ /** Returns a mutable reference to an existing type descriptor. This can be
+ used to e.g. override the creator function of a type added by a base class. */
+ template<typename T>
+ typename CollectionItemTypeChooser<T>::Type &modify_type();
private:
- /// Returns the descriptor for a type, or null if one isn't defined.
+ /** Returns the descriptor for a type, or null if one isn't defined. An
+ optional name can be given to prioritize matching types. */
template<typename T>
- CollectionItemTypeBase *get_type() const;
+ CollectionItemTypeBase *get_type(const std::string & = std::string()) const;
+
+ /// Gets a descriptor with the same type as another descriptor.
+ CollectionItemTypeBase *get_type(const CollectionItemTypeBase &) const;
/// Returns the descriptor for an item, or null if it's of an unknown type.
CollectionItemTypeBase *get_type_for_item(const Variant &) const;
protected:
- void add_source(CollectionSource &);
+ /** Adds a source for automatically loading items. Sources are consulted
+ in the order they are added. */
+ void add_source(const CollectionSource &);
+
+public:
+ /** Opens a raw resource, without interpreting it as object data. Null is
+ returned if no such file is found. The caller must dispose of the returned
+ object when done with it. */
+ IO::Seekable *open_raw(const std::string &) const;
private:
void gather_names_from_sources(std::list<std::string> &, const CollectionItemTypeBase &) const;
void load_items_from_sources(const CollectionItemTypeBase &);
+
+protected:
+ /** Sets a fallback collection, which will be consulted if an item is not
+ found. */
+ void set_fallback(Collection *);
+
+ Collection *get_fallback() const { return fallback; }
};
template<typename T>
public:
virtual ~CollectionItemTypeBase();
+protected:
void set_keyword(const std::string &);
- const std::string &get_keyword() const { return kwd; }
void add_suffix(const std::string &);
+public:
+ const std::string &get_keyword() const { return kwd; }
bool match_name(const std::string &) const;
+ virtual bool is_same_type(const CollectionItemTypeBase &) const = 0;
virtual bool check_item_type(const Variant &) const = 0;
virtual void add_to_loader(Collection::Loader &) const = 0;
virtual bool can_create() const = 0;
virtual void create_item(Collection &, const std::string &) const = 0;
virtual void load_item(Collection &, Parser &, const std::string &) const = 0;
+ virtual void notify_item(Collection &, const std::string &, const Variant &) const = 0;
template<typename T>
bool can_extract() const
{
- for(std::vector<ExtractorBase *>::const_iterator i=extractors.begin(); i!=extractors.end(); ++i)
- if(dynamic_cast<Extractor<T> *>(*i))
+ for(ExtractorBase *e: extractors)
+ if(dynamic_cast<Extractor<T> *>(e))
return true;
return false;
}
template<typename T>
T *extract(const Variant &var) const
{
- for(std::vector<ExtractorBase *>::const_iterator i=extractors.begin(); i!=extractors.end(); ++i)
- if(Extractor<T> *ex = dynamic_cast<Extractor<T> *>(*i))
+ for(ExtractorBase *e: extractors)
+ if(Extractor<T> *ex = dynamic_cast<Extractor<T> *>(e))
return &ex->extract(var);
return 0;
}
Creator(FuncPtr f): func(f) { }
virtual T *create(Collection &coll, const std::string &name) const
- { return (static_cast<C &>(coll).*func)(name); }
+ { return (dynamic_cast<C &>(coll).*func)(name); }
+ };
+
+ struct NotifyeeBase
+ {
+ virtual ~NotifyeeBase() { }
+
+ virtual void notify(Collection &, const std::string &, T &) const = 0;
+ };
+
+ template<typename C>
+ struct Notifyee: NotifyeeBase
+ {
+ typedef void (C::*FuncPtr)(const std::string &, T &);
+
+ FuncPtr func;
+
+ Notifyee(FuncPtr f): func(f) { }
+
+ virtual void notify(Collection &coll, const std::string &name, T &item) const
+ { (dynamic_cast<C &>(coll).*func)(name, item); }
};
template<typename B>
};
CreatorBase *creat;
+ std::vector<NotifyeeBase *> notif;
public:
CollectionItemType():
~CollectionItemType()
{
delete creat;
+ for(NotifyeeBase *n: notif)
+ delete n;
}
/** Sets a datafile keyword for this item type. The Collection's loader
return *this;
}
- /** Adds a suffix that is used to match names when looking for future
+ /** Adds a suffix that is used to match names when looking for loadable
objects. There is no implied separator; a name matches if it ends with the
suffix. If a keyword is defined before any suffixes, then "."+keyword is
added as a suffix. */
return *this;
}
+ template<typename C>
+ CollectionItemType ¬ify(void (C::*func)(const std::string &, T &))
+ {
+ notif.push_back(new Notifyee<C>(func));
+ return *this;
+ }
+
+ virtual bool is_same_type(const CollectionItemTypeBase &other) const
+ { return dynamic_cast<const CollectionItemType<T> *>(&other); }
+
virtual bool check_item_type(const Variant &var) const
{ return var.check_type<RefPtr<T> >(); }
- virtual void add_to_loader(Collection::Loader &loader) const
- { loader.add(kwd, &Collection::Loader::item<T, T>); }
+ virtual void add_to_loader(Collection::Loader &) const
+ { }
virtual bool can_create() const
{ return creat!=0; }
coll.add(name, obj);
}
+ virtual void load_item(Collection &, Parser &, const std::string &) const
+ {
+ throw std::runtime_error("this type cannot be loaded");
+ }
+
+ virtual void notify_item(Collection &coll, const std::string &name, const Variant &var) const
+ {
+ RefPtr<T> obj = var.value<RefPtr<T> >();
+ for(NotifyeeBase *n: notif)
+ n->notify(coll, name, *obj);
+ }
+};
+
+
+template<typename T>
+class LoadableCollectionItemType: public CollectionItemType<T>
+{
+public:
+ virtual void add_to_loader(Collection::Loader &loader) const
+ { loader.add(this->kwd, &Collection::Loader::item<T, T>); }
+
virtual void load_item(Collection &coll, Parser &parser, const std::string &name) const
{
RefPtr<T> obj = new T;
}
template<typename T>
-CollectionItemType<T> &Collection::add_type()
+typename CollectionItemTypeChooser<T>::Type &Collection::add_type()
{
- CollectionItemType<T> *type = new CollectionItemType<T>;
+ typename CollectionItemTypeChooser<T>::Type *type = new typename CollectionItemTypeChooser<T>::Type;
types.push_back(type);
return *type;
}
template<typename T>
-CollectionItemTypeBase *Collection::get_type() const
+typename CollectionItemTypeChooser<T>::Type &Collection::modify_type()
{
- for(TypeList::const_iterator j=types.begin(); j!=types.end(); ++j)
- if(dynamic_cast<CollectionItemType<T> *>(*j))
- return *j;
- for(TypeList::const_iterator j=types.begin(); j!=types.end(); ++j)
- if((*j)->can_extract<T>())
- return *j;
- return 0;
+ for(CollectionItemTypeBase *t: types)
+ if(CollectionItemType<T> *tt = dynamic_cast<CollectionItemType<T> *>(t))
+ return *tt;
+
+ throw std::logic_error("type not found in collection");
+}
+
+template<typename T>
+CollectionItemTypeBase *Collection::get_type(const std::string &name) const
+{
+ for(CollectionItemTypeBase *t: types)
+ if(dynamic_cast<CollectionItemType<T> *>(t))
+ return t;
+ CollectionItemTypeBase *type = 0;
+ for(CollectionItemTypeBase *t: types)
+ if(t->can_extract<T>())
+ {
+ if(!name.empty() && t->match_name(name))
+ return t;
+ type = t;
+ }
+ return type;
}
} // namespace DataFile
projects / libs / datafile.git / blobdiff