Add a filter registry class

src/filter.hh

@@ -0,0 +1,16 @@
+#ifndef filter_hh_INCLUDED
+#define filter_hh_INCLUDED
+
+#include <functional>
+
+namespace Kakoune
+{
+
+class DisplayBuffer;
+
+typedef std::function<void (DisplayBuffer& display_buffer)> FilterFunc;
+typedef std::pair<std::string, FilterFunc> FilterAndId;
+
+}
+
+#endif // filter_hh_INCLUDED

src/filter_registry.cc

@@ -0,0 +1,30 @@
+#include "filter_registry.hh"
+
+#include "exception.hh"
+
+namespace Kakoune
+{
+
+struct factory_not_found : public runtime_error
+{
+    factory_not_found() : runtime_error("factory not found") {}
+};
+
+void FilterRegistry::register_factory(const std::string& name,
+                                      const FilterFactory& factory)
+{
+    assert(m_factories.find(name) == m_factories.end());
+    m_factories[name] = factory;
+}
+
+FilterAndId FilterRegistry::get_filter(const std::string& name,
+                                       const FilterParameters& parameters)
+{
+    auto it = m_factories.find(name);
+    if (it == m_factories.end())
+        throw factory_not_found();
+
+    return it->second(parameters);
+}
+
+}

src/filter_registry.hh

@@ -0,0 +1,32 @@
+#ifndef filter_registry_h_INCLUDED
+#define filter_registry_h_INCLUDED
+
+#include <string>
+#include <unordered_map>
+
+#include "filter.hh"
+#include "utils.hh"
+
+namespace Kakoune
+{
+
+typedef std::vector<std::string> FilterParameters;
+
+typedef std::function<FilterAndId (const FilterParameters& params)> FilterFactory;
+
+class FilterRegistry : public Singleton<FilterRegistry>
+{
+public:
+    void register_factory(const std::string& name,
+                          const FilterFactory& factory);
+
+    FilterAndId get_filter(const std::string& factory_name,
+                           const FilterParameters& parameters);
+
+private:
+    std::unordered_map<std::string, FilterFactory> m_factories;
+};
+
+}
+
+#endif // filter_registry_h_INCLUDED