From dfe71a21e5a190e5228964265c62416779454bec Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Sat, 27 Oct 2018 21:11:27 +0200
Subject: Prototype LV2 midname extension

---
 midnam_lv2.h | 37 +++++++++++++++++++++++++
 pluginlv2.cc | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 pluginlv2.h  | 12 ++++++++
 3 files changed, 138 insertions(+)
 create mode 100644 midnam_lv2.h

diff --git a/midnam_lv2.h b/midnam_lv2.h
new file mode 100644
index 0000000..a8e3f8e
--- /dev/null
+++ b/midnam_lv2.h
@@ -0,0 +1,37 @@
+#define LV2_MIDNAM_URI "http://ardour.org/lv2/midnam"
+#define LV2_MIDNAM_PREFIX LV2_MIDNAM_URI "#"
+#define LV2_MIDNAM__interface LV2_MIDNAM_PREFIX "interface"
+#define LV2_MIDNAM__update LV2_MIDNAM_PREFIX "update"
+
+typedef void* LV2_Midnam_Handle;
+
+/** a LV2 Feature provided by the Host to the plugin */
+typedef struct {
+	/** Opaque host data */
+	LV2_Midnam_Handle handle;
+	/** Request from run() that the host should re-read the midnam */
+	void (*update)(LV2_Midnam_Handle handle);
+} LV2_Midnam;
+
+typedef struct {
+	/** Query midnam document. The plugin
+	 * is expected to return a null-terminated XML
+	 * text which is a valid midnam desciption
+	 * (or NULL in case of error).
+	 *
+	 * The midnam <Model> must be unique and
+	 * specific for the given plugin-instance.
+	 */
+	char* (*midnam)(LV2_Handle instance);
+
+	/** The unique model id used ith the midnam,
+	 * (or NULL).
+	 */
+	char* (*model)(LV2_Handle instance);
+
+	/** free allocated strings. The host
+	 * calls this for every value returned by
+	 * \ref midnam and \ref model.
+	 */
+	void (*free)(char*);
+} LV2_Midnam_Interface;
diff --git a/pluginlv2.cc b/pluginlv2.cc
index 7593ff4..fd0bfbf 100644
--- a/pluginlv2.cc
+++ b/pluginlv2.cc
@@ -27,6 +27,7 @@
 #include "pluginlv2.h"
 
 #include <iostream>
+#include <sstream>
 #include <assert.h>
 
 #include "midievent.h"
@@ -121,6 +122,13 @@ LV2_Handle PluginLV2::instantiate(const struct _LV2_Descriptor* descriptor,
 		}
 #endif
 
+#ifdef DISPLAY_INTERFACE
+		if(uri == LV2_MIDNAM__update)
+		{
+			plugin_lv2->midnam = (LV2_Midnam*)data;
+		}
+#endif
+
 		++features;
 	}
 
@@ -355,6 +363,13 @@ void PluginLV2::run(LV2_Handle instance, uint32_t sample_count)
 
 	plugin_lv2->pos += sample_count;
 
+#ifdef MIDNAME_INTERFACE
+	if (0) // XXX drumkit changed
+	{
+		plugin_lv2->midnam->update (plugin_lv2->midnam->handle);
+	}
+#endif
+
 #ifdef DISPLAY_INTERFACE
 	if(plugin_lv2->queue_draw)
 	{
@@ -470,6 +485,72 @@ LV2_Inline_Display_Image_Surface* PluginLV2::inlineRender(LV2_Handle instance,
 	return &plugin_lv2->surf;
 }
 
+#ifdef MIDNAME_INTERFACE
+char* PluginLV2::MidnamFile (LV2_Handle instance)
+{
+	PluginLV2* plugin_lv2 = (PluginLV2*)instance;
+	std::stringstream ss;
+	ss <<
+		"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
+		"<!DOCTYPE MIDINameDocument PUBLIC \"-//MIDI Manufacturers Association//DTD MIDINameDocument 1.0//EN\" \"http://dev.midi.org/dtds/MIDINameDocument10.dtd\">\n"
+		"<MIDINameDocument>\n"
+		"  <Author/>\n"
+		"  <MasterDeviceNames>\n"
+		"    <Manufacturer>The Drum Gizmo Foundation</Manufacturer>\n"
+		"    <Model>Drumgizmo:" << ((const void *) instance) << "</Model>\n"; //<< needs to match MidnamModel()
+
+	ss << "    <CustomDeviceMode Name=\"Default\">\n";
+	ss << "      <ChannelNameSetAssignments>\n";
+	for (int c = 0; c < 16; ++c)
+	{
+		ss << "        <ChannelNameSetAssign Channel=\"" << (c + 1) << "\" NameSet=\"Presets\"/>\n";
+	}
+	ss << "      </ChannelNameSetAssignments>\n";
+	ss << "    </CustomDeviceMode>\n";
+
+
+	ss <<
+		"    <ChannelNameSet Name=\"Presets\">\n"
+		"      <AvailableForChannels>\n";
+	for (int c = 0; c < 16; ++c) {
+		ss << "        <AvailableChannel Channel=\"" << (c + 1) << "\" Available=\"true\"/>\n";
+	}
+	ss <<
+		"      </AvailableForChannels>\n"
+		"      <UsesNoteNameList Name=\"Notes\"/>\n"
+		"      <PatchBank Name=\"User Patches\">\n"
+		"        <PatchNameList Name=\"User Patches\"/>\n"
+		"       </PatchBank>\n"
+		"    </ChannelNameSet>\n"
+		"    <NoteNameList Name=\"Notes\">\n";
+
+	// XXX TODO  ask plugin_lv2, iterate over mapped samples
+	ss << "      <Note Number=\"36\" Name=\"KickDrum\"/>\n";
+	ss << "      <Note Number=\"38\" Name=\"Snare\"/>\n";
+	// XXX
+
+	ss <<
+		"    </NoteNameList>\n"
+		"  </MasterDeviceNames>\n"
+		"</MIDINameDocument>";
+
+	return strdup (ss.str().c_str());
+}
+
+char* PluginLV2::MidnamModel (LV2_Handle instance)
+{
+	char* rv = (char*) malloc (64 * sizeof (char));
+	snprintf (rv, 64, "Drumgizmo:%p", (void*) instance);
+	rv[63] = 0;
+	return rv;
+}
+
+void  PluginLV2::MidnamFree  (char* v)
+{
+	free (v);
+}
+#endif
+
 const void* PluginLV2::extensionData(const char *uri)
 {
 	if(!strcmp(uri, LV2_STATE__interface))
@@ -485,6 +566,14 @@ const void* PluginLV2::extensionData(const char *uri)
 	}
 #endif
 
+#ifdef MIDNAME_INTERFACE
+	static const LV2_Midnam_Interface midnam = { MidnamFile, MidnamModel, MidnamFree };
+	if (!strcmp (uri, LV2_MIDNAM__interface))
+	{
+		return &midnam;
+	}
+#endif
+
 	return nullptr;
 }
 
diff --git a/pluginlv2.h b/pluginlv2.h
index 86a661e..10f816e 100644
--- a/pluginlv2.h
+++ b/pluginlv2.h
@@ -36,11 +36,16 @@
 #include <lv2/lv2plug.in/ns/extensions/ui/ui.h>
 
 #define DISPLAY_INTERFACE
+#define MIDNAME_INTERFACE
 
 #ifdef DISPLAY_INTERFACE
 #include "inline-display.h"
 #endif
 
+#ifdef MIDNAME_INTERFACE
+#include "midnam_lv2.h"
+#endif
+
 enum class LV2Ports
 {
 	FreeWheel = 0,
@@ -256,6 +261,13 @@ private:
 	                                                      uint32_t max_h);
 #endif
 
+#ifdef MIDNAME_INTERFACE
+	LV2_Midnam* midnam{nullptr};
+	static char* MidnamFile  (LV2_Handle instance);
+	static char* MidnamModel (LV2_Handle instance);
+	static void  MidnamFree  (char*);
+#endif
+
 	bool active{false};
 
 	//
-- 
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