Update CC-to-Automation script: use Lua-Dialog for parameters

scripts/_midi_cc_to_automation.lua

@@ -1,17 +1,65 @@
 ardour { ["type"] = "Snippet", name = "MIDI CC to Plugin Automation" }
 
 function factory () return function ()
-	-- target automation lane: a plugin parameter on a track
-	local tgt = Session:route_by_name('Audio') -- get track
-	assert (not tgt:isnil ())
-	-- get AutomationList, ControlList and ParameterDescriptor
-	-- of the first plugin's 2nd parameter
-	local al, _, pd = ARDOUR.LuaAPI.plugin_automation (tgt:nth_plugin (0), 1)
+	-- find target parameters
+	local targets = {}
+	local have_entries = false
+	for r in Session:get_routes():iter() do -- for every track/bus
+		local i = 0;
+		while 1 do -- iterate over all plugins on the route
+			local proc = r:nth_plugin (i)
+			if proc:isnil () then break end
+			if not targets [r:name ()] then targets [r:name ()] = {} end
+			targets [r:name ()][proc:display_name ()] = {};
+			local plug = proc:to_insert ():plugin (0)
+			local n = 0
+			for j = 0, plug:parameter_count () - 1 do -- iterate over all plugin parameters
+				if plug:parameter_is_control(j) then
+					if plug:parameter_is_input(j) then
+						local nn = n
+						targets [r:name ()][proc:display_name ()][plug:parameter_label(j)] = function () return {["p"] = proc, ["n"] = nn} end
+						have_entries = true
+					end
+					n = n + 1
+				end
+			end
+			i = i + 1
+		end
+	end
 
-	-- Source MIDI CC parameter
-	local midi_channel = 0 -- 0..15
-	local cc_param = 0x56
+	-- bail out if there are no parameters
+	if not have_entries then
+		LuaDialog.Message ("CC to Plugin", "No Plugins found", LuaDialog.MessageType.Info, LuaDialog.ButtonType.Close):run()
+		collectgarbage ()
+		return
+	end
 
+	-- create a dialog, ask user which MIDI-CC to map and to what parameter
+	local dialog_options = {
+		{ type = "dropdown", key = "param", title = "Target Parameter", values = targets },
+		{ type = "number", key = "channel", title = "Channel",  min = 1, max = 16, step = 1, digits = 0 },
+		{ type = "number", key = "ccparam", title = "CC Parameter",  min = 0, max = 127, step = 1, digits = 0 }
+	}
+	local od = LuaDialog.Dialog ("Select Taget", dialog_options)
+	local rv = od:run()
+
+	if not rv then
+		od = nil collectgarbage ()
+		return;
+	end
+
+	-- parse user response
+
+	local midi_channel = rv["channel"] - 1
+	local cc_param = rv["ccparam"]
+	local pp = rv["param"]()
+	local al, _, pd = ARDOUR.LuaAPI.plugin_automation (pp["p"], pp["n"])
+	od = nil collectgarbage ()
+	assert (al)
+	assert (midi_channel >= 0 and midi_channel < 16)
+	assert (cc_param >= 0 and cc_param < 128)
+
+	-- all systems go
 	local add_undo = false
 	Session:begin_reversible_command ("CC to Automation")
 	local before = al:get_state()