--- Auto Audio Source Mute
-- 
-- Mutes selected audio source (if unmuted) 

 
obs = obslua
bit = require("bit")

source_def = {}
source_def.id = "Auto_Mute_Source"
source_def.type = OBS_SOURCE_TYPE_INPUT
source_def.output_flags = bit.bor(obs.OBS_SOURCE_CUSTOM_DRAW)
muted = false
changed = true
volume = 0
source_ptr = nil
incallback = false
duck = false
muteActive = 0
duckVolume = 0
audio_source_name = ""
fade_direction = true
fade2Volume = 0
fade_speed = 1

source_def.get_name = function()
	return "Auto Mute/Duck Audio" 
end

source_def.create = function(settings, source)
    data = {}
	sh = obs.obs_source_get_signal_handler(source)
	obs.signal_handler_connect(sh,"activate",active)   --Set Active Callback
	obs.signal_handler_connect(sh,"deactivate",deactive)	   --Set Preview Callback
	source_ptr = source
	return data
end

function rename_callback()
   obs.timer_remove(rename_callback)
   local sources = obs.obs_enum_sources()
    if (sources ~= nil) then
        local t = 0
        for _, source in ipairs(sources) do
            local source_id = obs.obs_source_get_id(source)
            if source_id == "Auto_Mute_Source" then
				t = t + 1
			end
		end
		if t>0 then
			for _, source in ipairs(sources) do
				local source_id = obs.obs_source_get_id(source)
				if source_id == "Auto_Mute_Source" then
					local settings = obs.obs_source_get_settings(source)
	                local audio_source_name = obs.obs_data_get_string(settings, "audio_prop")					
					local direction = obs.obs_data_get_bool(settings,"dir")
					local duck = obs.obs_data_get_bool(settings,"duck")
					local duckVolume = 60+obs.obs_data_get_int(settings,"duckVolume")

					
					local value = duckVolume
					if (direction) then 
					    value = volume
					end
					local color = "50FF00"
					if (value > 40) then color = "FADB2C" end
					if (value > 51) then color = "FF4319" end
					local newname = ""
					if direction then 
					    if duck then
						  newname = "(" .. t .. ") <b>" ..  audio_source_name .. "</b> Vol set to " .. 60-duckVolume ..  string.format(" (<span style='color:#%s;'>%.1f db</span>)",color,per_to_db(duckVolume))
						else
						  newname = "(" .. t .. ") UnMute: <b>" .. audio_source_name .. "</b>"
						end
					else
					    if duck then
						  newname = "(" .. t .. ") <b>" ..  audio_source_name .. "</b> Vol set to " .. 60-duckVolume .. string.format(" (<span style='color:#%s;'>%.1f db</span>)",color,per_to_db(duckVolume))
						else					
						  newname = "(" .. t .. ") Mute: <b>" .. audio_source_name .. "</b>"
						end
					end
					t = t - 1
					
					obs.obs_source_set_name(source, newname)						
					obs.obs_data_release(settings) -- release memory
				end
			end	
		end
	end
    obs.source_list_release(sources)
end

function start_fade_timer()
    obs.timer_add(fade_callback, 50)
end

function fade_callback()
	local audio_source = obs.obs_get_source_by_name(audio_source_name)	
	if audio_source ~= nil then 
		local volume = mul_to_db(obs.obs_source_get_volume(audio_source))
		local nextVol = volume
		if volume ~= fade2Volume then 
			if (fade2Volume > volume) then
				nextVol = volume+fade_speed
				if (nextVol > fade2Volume) then
				    nextVol = fade2Volume
					obs.remove_current_callback()
				end
			else
				nextVol = volume-fade_speed
				if (nextVol < fade2Volume) then
				    nextVol = fade2Volume
					obs.remove_current_callback()
				end				
			end
			obs.obs_source_set_volume(audio_source,db_to_mul(nextVol))  
		end	
	obs.obs_source_release(audio_source)	
	end
end	

source_def.save = function (data, settings)
	if changed then 
		obs.timer_add(rename_callback, 3000) -- wait long enough for save to complete so callback is only once
	end
	changed = false
end


function change_duck_property(props, prop, settings)
    obs.obs_property_set_visible(obs.obs_properties_get(props, "duckVolume"), obs.obs_data_get_bool(settings, "duck"))	
    obs.obs_property_set_visible(obs.obs_properties_get(props, "fadeOutSpeed"), obs.obs_data_get_bool(settings, "duck"))	
    obs.obs_property_set_visible(obs.obs_properties_get(props, "fadeInSpeed"), obs.obs_data_get_bool(settings, "duck"))	
    return true
end

source_def.get_properties = function (data)
	changed = true
	props = obs.obs_properties_create()
	local source_prop = obs.obs_properties_add_list(props, "audio_prop", "Set Audio Source", obs.OBS_COMBO_TYPE_LIST, obs.OBS_COMBO_FORMAT_STRING)	
	local sources = obs.obs_enum_sources()

	if sources ~= nil then
		local n = {}
		local source_id = nil
		for _, source in ipairs(sources) do
			if bit.band(obs.obs_source_get_output_flags(source),obs.OBS_SOURCE_AUDIO) > 0  then
				n[#n+1] = obs.obs_source_get_name(source)
			end
		end
		table.sort(n)
		for _, name in ipairs(n) do
			obs.obs_property_list_add_string(source_prop, name, name)
		end
	end
	obs.source_list_release(sources)
	obs.obs_properties_add_button(props, "show_help_button", "SHOW HELP", show_help_button)
	obs.obs_properties_add_bool(props,"dir","Unmute if Muted (Default is Mute if Unmuted): ")
	obs.obs_properties_add_bool(props,"restore","Restore Mute State/Volume Level on Exit: ")
	local duck_prop = obs.obs_properties_add_bool(props,"duck","Duck Volume instead of Mute: ")
    obs.obs_property_set_modified_callback(duck_prop, change_duck_property)	
	local dv = obs.obs_properties_add_int_slider(props,"duckVolume","Ducking Volume:",-60,0,1)
	local dv = obs.obs_properties_add_int_slider(props,"fadeOutSpeed","Fade Speed Activating   Source (1-10):",1,10,1)
	local dv = obs.obs_properties_add_int_slider(props,"fadeInSpeed", "Fade Speed Deactivating Source (1-10):",1,10,1)
	return props
end	


help =
    "▪▪▪▪▪ USAGE HELP ▪▪▪▪▪▲- CLICK TO CLOSE -▲▪▪▪▪▪\n\n" ..
    "Settings for Auto Mute/Duck Source \n" ..
    "==============================\n" ..
    "Normal operation is to mute selected source when then scene loads\n" ..
    "Check 'Unmute if Muted:' to unmute a selected source when the scene loads\n" ..
    "Check 'Restore Mute State/Volume level on Exit:' to restore original volume setting on scene close\n" ..
    "Check 'Duck Volume instead of Mute:' to set volume level for the selected source for this scene\n" ..
    "Ducking sets source volume to the selected Ducking Volume\n\n" ..
    "Note: OBS opens the next scene BEFORE it closes the prior scene!\n" ..
	"      For this reason, Restore option is ignored if next scene sets the same source.\n"


-----------------------------------------------------------------------------------------------------------------------
-- Show/Hide the Help Button Text
-----------------------------------------------------------------------------------------------------------------------
function show_help_button(props, prop, settings)
    local hb = obs.obs_properties_get(props, "show_help_button")
    showhelp = not showhelp
    if showhelp then
        obs.obs_property_set_description(hb, help)
    else
        obs.obs_property_set_description(hb, "SHOW HELP")
    end
    return true
end

function script_description()
	return [[<span style="color: #FFD966;"><b>AUTO MUTE-DUCK AUDIO SOURCE</b></span><br><B>Ver 1.3</B> &nbsp; &nbsp;by DCStrato<br><br><span style="color: #9DFB9D;">Mutes/Unmutes or sets Audio level for a Selected Audio<br>Source during the Current Scene with optional Restore.<br></span><br><span style="color: #FB9D9D;">Property options are in the Source when added to a Scene</span>]]
end

function per_to_db(level)
  local def = level / 60.0
  local db = 0
  if (def >= 1.0) then 
	    db = 0.0
  elseif (def <= 0.0) then
		db = -100;
  else
		db = 6 - (102 * (1/(17 ^ def)))
  end
  return db
end

function db_to_mul(db)
	if ( db == 0) then
	  return 0
	else
	  return  10 ^ (db / 20.0)
	end
end

function mul_to_db(mul)
     if (mul == 0) then
	   return 1;
	 else
       return 20 * math.log10(mul)
 	 end
end

function update(cd)
	changed = true
end

function active(cd)
    muteActive = muteActive + 1
	local source = obs.calldata_source(cd,"source")
	local settings = obs.obs_source_get_settings(source)
	audio_source_name = obs.obs_data_get_string(settings, "audio_prop")
	fade_direction = obs.obs_data_get_bool(settings,"dir")
	duck = obs.obs_data_get_bool(settings,"duck")
	duckVolume = per_to_db(60+obs.obs_data_get_int(settings,"duckVolume"))
	fade_speed = obs.obs_data_get_int(settings,"fadeInSpeed")
	obs.obs_data_release(settings)			
	local audio_source = obs.obs_get_source_by_name(audio_source_name)	
	if audio_source ~= nil then 
		muted = obs.obs_source_muted(audio_source)
		volume = mul_to_db(obs.obs_source_get_volume(audio_source))
		if duck then 
			if volume ~= duckVolume then 
				fade2Volume = duckVolume
				start_fade_timer()
			end	
        else 			
			if not fade_direction then 
				if not muted then
					obs.obs_source_set_muted(audio_source,true)  -- mute if unmuted
				end
			else
				if muted then
					obs.obs_source_set_muted(audio_source,false)  -- unmute if muted  
				end
			end
		end
		obs.obs_source_release(audio_source)	
	end
end

function deactive(cd)
	local source = obs.calldata_source(cd,"source")
	local settings = obs.obs_source_get_settings(source)
	local audio_source_name = obs.obs_data_get_string(settings, "audio_prop")
	local direction = obs.obs_data_get_bool(settings,"dir")
	local force = obs.obs_data_get_bool(settings,"force")
	local restore = obs.obs_data_get_bool(settings,"restore")	
	local duck = obs.obs_data_get_bool(settings,"duck")
	local duckVolume = per_to_db(60+obs.obs_data_get_int(settings,"duckVolume"))
	fade_speed = obs.obs_data_get_int(settings,"fadeOutSpeed")	
	obs.obs_data_release(settings)			
	local audio_source = obs.obs_get_source_by_name(audio_source_name)	
	if audio_source ~= nil and restore and (muteActive == 1 or (audio_source_name ~= loaded_source_name)) then 
		if duck then 
		   fade2Volume = volume -- restore prior volume				
		   start_fade_timer()
		else
		   obs.obs_source_set_muted(audio_source,muted)  -- restore prior mute state
		end
		obs.obs_source_release(audio_source)		
	end
	muteActive = muteActive - 1
end

obs.obs_register_source(source_def)