X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fcollection.h;h=87af3a2c2c606cde35d00abd8a20bf092744e19d;hb=b26fbba2bf5d53554325762b8022c501b3b8c8fb;hp=34b1260c4c42b729311964736b2efc02343c03fb;hpb=41e78ee91ca058ead90fa1c8ee4339d2ef1b0f31;p=libs%2Fdatafile.git

diff --git a/source/collection.h b/source/collection.h
index 34b1260..87af3a2 100644
--- a/source/collection.h
+++ b/source/collection.h
@@ -1,6 +1,7 @@
 #ifndef MSP_DATAFILE_COLLECTION_H_
 #define MSP_DATAFILE_COLLECTION_H_
 
+#include <msp/core/attributes.h>
 #include <msp/core/maputils.h>
 #include <msp/core/refptr.h>
 #include "collectionsource.h"
@@ -18,6 +19,20 @@ class CollectionItemTypeBase;
 template<typename T>
 class CollectionItemType;
 
+template<typename T>
+class LoadableCollectionItemType;
+
+template<typename T, bool = HasLoader<T>::value>
+struct CollectionItemTypeChooser;
+
+template<typename T>
+struct CollectionItemTypeChooser<T, true>
+{ typedef LoadableCollectionItemType<T> Type; };
+
+template<typename T>
+struct CollectionItemTypeChooser<T, false>
+{ typedef CollectionItemType<T> Type; };
+
 /**
 A collection of objects that can be loaded from a datafile.  Each object is
 identified by a name, which must be unique across the entire collection.
@@ -43,7 +58,7 @@ public:
 	*/
 	class Loader: public DataFile::Loader
 	{
-		template<typename T> friend class CollectionItemType;
+		template<typename T> friend class LoadableCollectionItemType;
 
 	private:
 		Collection &coll;
@@ -68,8 +83,8 @@ public:
 
 private:
 	typedef std::map<std::string, Variant> ItemMap;
-	typedef std::list<CollectionItemTypeBase *> TypeList;
-	typedef std::list<const CollectionSource *> SourceList;
+	typedef std::vector<CollectionItemTypeBase *> TypeList;
+	typedef std::vector<const CollectionSource *> SourceList;
 
 	TypeList types;
 	ItemMap items;
@@ -120,25 +135,44 @@ public:
 		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 RemoveConst<T>::Type>(i->second) : 0);
+	}
+
+	template<typename T>
+	T *find(const std::string &name)
+	{
+		typedef typename RemoveConst<T>::Type NCT;
+		const Variant *var = find_var(name, get_type<NCT>(name));
+		return (var ? &extract<NCT>(*var) : 0);
+	}
+
 private:
 	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)
+		for(std::vector<const Variant *>::const_iterator i=vars.begin(); i!=vars.end(); ++i)
 			result.push_back(&extract<T>(**i));
 		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);
@@ -170,7 +204,7 @@ public:
 	template<typename T>
 	std::list<T *> get_list() const
 	{
-		std::list<const Variant *> vars;
+		std::vector<const Variant *> vars;
 		gather_items<typename RemoveConst<T>::Type>(&vars, 0, 0, false);
 		return extract_list<T>(vars);
 	}
@@ -184,7 +218,7 @@ public:
 		if(type)
 			load_items_from_sources(*type);
 
-		std::list<const Variant *> vars;
+		std::vector<const Variant *> vars;
 		gather_items<typename RemoveConst<T>::Type>(&vars, 0, type, true);
 		return extract_list<T>(vars);
 	}
@@ -234,7 +268,12 @@ protected:
 	/** 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.  An
@@ -260,7 +299,8 @@ public:
 	IO::Seekable *open_raw(const std::string &) const;
 
 protected:
-	IO::Seekable *open_from_sources(const std::string &n) { return open_raw(n); }
+	// Deprecated.  Use open_raw instead.
+	DEPRECATED IO::Seekable *open_from_sources(const std::string &n) { return open_raw(n); }
 
 private:
 	void gather_names_from_sources(std::list<std::string> &, const CollectionItemTypeBase &) const;
@@ -316,9 +356,11 @@ protected:
 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;
@@ -403,7 +445,7 @@ public:
 		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. */
@@ -441,8 +483,8 @@ public:
 	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; }
@@ -456,6 +498,20 @@ public:
 			coll.add(name, obj);
 	}
 
+	virtual void load_item(Collection &, Parser &, const std::string &) const
+	{
+		throw std::runtime_error("this type cannot be loaded");
+	}
+};
+
+
+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;
@@ -479,13 +535,23 @@ T &Collection::extract(const Variant &var) const
 }
 
 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>
+typename CollectionItemTypeChooser<T>::Type &Collection::modify_type()
+{
+	for(TypeList::const_iterator j=types.begin(); j!=types.end(); ++j)
+		if(CollectionItemType<T> *t = dynamic_cast<CollectionItemType<T> *>(*j))
+			return *t;
+
+	throw std::logic_error("type not found in collection");
+}
+
 template<typename T>
 CollectionItemTypeBase *Collection::get_type(const std::string &name) const
 {