From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 20 Jan 2012 20:28:06 +0000 (+0200)
Subject: Add DirectoryCollection class for creating directory-backed collections
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=a4091f14dfbf4d5f822fa26740a7b3f305c449e6;p=libs%2Fdatafile.git

Add DirectoryCollection class for creating directory-backed collections
---

diff --git a/source/directorycollection.cpp b/source/directorycollection.cpp
new file mode 100644
index 0000000..25808d6
--- /dev/null
+++ b/source/directorycollection.cpp
@@ -0,0 +1,41 @@
+#include <msp/fs/stat.h>
+#include "directorycollection.h"
+
+using namespace std;
+
+namespace Msp {
+namespace DataFile {
+
+DirectoryCollection::DirectoryCollection()
+{
+	set_directory(".");
+}
+
+void DirectoryCollection::set_directory(const FS::Path &d)
+{
+	dirs.clear();
+	add_directory(d);
+}
+
+void DirectoryCollection::add_directory(const FS::Path &d)
+{
+	dirs.push_back(d);
+}
+
+bool DirectoryCollection::lookup_file(const string &name, FS::Path &result) const
+{
+	for(list<FS::Path>::const_iterator i=dirs.begin(); i!=dirs.end(); ++i)
+	{
+		FS::Path file_path = *i/name;
+		if(FS::exists(file_path))
+		{
+			result = file_path;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+} // namespace DataFile
+} // namespace Msp
diff --git a/source/directorycollection.h b/source/directorycollection.h
new file mode 100644
index 0000000..93f9354
--- /dev/null
+++ b/source/directorycollection.h
@@ -0,0 +1,52 @@
+#ifndef MSP_DATAFILE_DIRECTORYCOLLECTION_H_
+#define MSP_DATAFILE_DIRECTORYCOLLECTION_H_
+
+#include <msp/fs/path.h>
+#include "collection.h"
+
+namespace Msp {
+namespace DataFile {
+
+/**
+A Collection that can automatically load items from files in a directory.
+*/
+class DirectoryCollection: public Collection
+{
+private:
+	std::list<FS::Path> dirs;
+
+public:
+	DirectoryCollection();
+
+protected:
+	void set_directory(const FS::Path &);
+	void add_directory(const FS::Path &);
+
+	template<typename T>
+	CollectionItemType<T> &add_type()
+	{
+		return Collection::add_type<T>().creator(&DirectoryCollection::create<T>);
+	}
+
+private:
+	template<typename T>
+	T *create(const std::string &name)
+	{
+		FS::Path file;
+		if(lookup_file(name, file))
+		{
+			RefPtr<T> item = new T;
+			load(*item, file.str());
+			return item.release();
+		}
+		else
+			return 0;
+	}
+
+	bool lookup_file(const std::string &, FS::Path &) const;
+};
+
+} // namespace DataFile
+} // namespace Msp
+
+#endif