-- Configurable NPC
-- This is a configurable NPC
--  

-- Translator
local S = mobs.translator

local vlog = mobs.vlog or "action" --"info"
local vlog =  "action" --"info"
-- Mod related infos
local modname = minetest.get_current_modname()
local modpath = minetest.get_modpath(modname)

local mob_name = "npc_idler"
local icprefix=modname..'_icon_'

local mod_storage = minetest.get_mod_storage()

local serialized_mob_data = mod_storage:get_string('mob_data')
mobs.npcs.mob_data = minetest.deserialize(serialized_mob_data) or {}

-- ------------------
--
-- helper function
--


local function find_in_array(needle,stack)
    if needle and stack then
        for k,v in ipairs(stack) do
          if v == needle then
            return k
          end
        end
    end
    return nil
end


data_values = {
	"nametag_color",
	"nametag",
	"infotext",
	"textures",
	"infotext",
	"wield_item",
	"visual_size",
	"action",
	}
data_serialize = {
	textures = true,
	action = true,
	}

local function save_node_meta(pos,data)

	local meta = minetest.get_meta(pos)

	for _,v in ipairs(data_values) do
		if data_serialize[v] then
			local szv = minetest.serialize(data[v])
			meta:set_string(v,szv)
		else
			meta:set_string(v,data[v])
		end

	end
end

local function get_data_from_node_meta(pos)
	local meta = minetest.get_meta(pos)
	local data = {}

	for _,v in ipairs(data_values) do
		if data_serialize[v] then
			data[v] = minetest.deserialize(meta:get_string(v))
		else
			data[v] = meta:get_string(v)
		end
	end
	return data
end

local function get_mob_data(pos)
    local key = minetest.pos_to_string(pos)
    return mobs.npcs.mob_data[key] or get_data_from_node_meta(pos)		
end

local function set_mob_data(pos,data)
    local key = minetest.pos_to_string(pos)
    mobs.npcs.mob_data[key] = data
    save_node_meta(pos,data)
    -- local sz = minetest.serialize(mobs.npcs.mob_data)
	-- mod_storage:set_string('mob_data',sz)
end



-- ------------------
--
-- helper function
--

-- ------------------
--
-- helper function
--


mobs.npcs.interactions = {
    default = { 
        icon = icprefix..'chat_random.png',
        desc = S("Say one of the default random chat message strings"),
        on_rightclick = mobs.npcs.random_message_on_rightclick
        },
    say = { 
        icon = icprefix..'chat.png',
        desc = S("Say one of the lines below as a chat message"),
        formfields = {
            {'textarea','message','',4},
            },
        on_rightclick = mobs.npcs.message_on_rightclick,
    },
	-- DONE: Set a timeout between heals with a different message too
	-- TODO: Or set a limit per player per days 
    heal = { 
        icon = icprefix..'healer.png',
        desc = S("Heal the player"),
        formfields = {
            {'label','Say one of theses sentences while healing',0.5},
            {'textarea','message_heal','',3},
            {'label','Say one of theses sentences during cooldown',0.5},
            {'textarea','message_cooldown','',2},
            },
        message_heal = S("There you go... good as new !") 
						.. "\n" .. S("Oh you look bad, let fix you...")
						.. "\n" .. S("Not what I was expecting but... good for you !")
						.. '',
        message_cooldown = S("I'm tired.") 
						.. "\n" .. S("I'm resting for a bit...")
						.. "\n" .. S("I can't help you now.")
						.. "\n" .. S("Come back later.")
						.. '',
        on_rightclick = mobs.npcs.heal_on_rightclick,
    },
	-- Following actions are planned but do not exist at the moment
    --
    dialog = { 
        icon = icprefix..'dialog.png',
        desc = S("Open a dialog menu with a text and a choice of answers"),
        disabled = true,
    },
    ai = { 
        icon = icprefix..'ai.png',
        desc = S("Try to mimic an intercation with the player"),
        disabled = true,
    },
    craft = { 
        icon = icprefix..'crafter.png',
        desc = S("Open a special inventory where the player can give item and received some transformed output"),
        disabled = true,
    },
    give = { 
        icon = icprefix..'giver.png',
        desc = S("Give something to the player"),
        disabled = true,
    },
    alert_owner = { 
        icon = icprefix..'giver.png',
        desc = S("Send an alert to the owner (allowing)"),
        hidden = true,
    },
}    

--
-- Specific mob informations
--

local mob_id = modname..':'..mob_name
local spawner_id = modname..':'..mob_name..'_spawner'


-- Get base defintion
local mob_def = mobs.npcs.base_def
mob_def._spawner_pos = nil
local textures_string

-- Get textures
-- local textures = mobs.npcs.get_textures_array("character_lambda_",modname)
-- if textures then 
    -- mob_def.textures = textures
-- end




--
-- Register Spawn condition and egg
--


-- More usable texture array
local ta = {}
for k,v in ipairs(mob_def.textures) do
    ta[k] = v[1]
end

    
local function get_npc_formspec(pos,n)
	
    local spos = pos.x .. "," .. pos.y .. "," .. pos.z
    local ww=8      -- window width
    local wh=9      -- window height
    local fw=5      -- field_width 
    local iy=0.5    -- index y

    -- Texture list as a sring
    local ts = table.concat(ta,',')
    
    local data = get_mob_data(pos) or {}

    if data.last_tab then n = data.last_tab end
    if not n then n = 1 end
    
    local n = tonumber(n)
    minetest.log(vlog, '['..modname..'] '..'Showing formspec '..n)

    -- print(dump(data))

    local ti = 1
    -- Get texture index
    if data.textures then ti = find_in_array(data.textures[1],ta) or 1 end
    


    local forms = {}
    -- Not empty data values
    local dv = {
       nametag = data.nametag or '',
       nametag_color = data.nametag_color or '',
       infotext = data.infotext or '',
       texture = ts or '',
       wield_item = data.wield_item or '',
       nametag = data.nametag or '',
    }
    forms[1] = 
        -- 'label[0,'.. iy - 0.5  ..';'..S('-- Menu de configuration --')..']' ..
        -- 'container[0,0]'..
        -- tooltip[<gui_element_name>;<tooltip_text>;<bgcolor>;<fontcolor>]
        'field[0.3,'.. iy+1 ..';'..fw..',0.3;nametag;'..S('Nom')..';'..dv.nametag..']' ..
        
        -- 'textarea[0.3,'.. iy+1.6 ..';'..fw..',1.6;infotext;'..S('InfoText')..';'..dv.infotext..']'..
        -- 'field[0.3,'.. iy+2.5 ..';'..fw..',0.5;nametag_color;'..S('Nametag Color')..';#61ff0170]' ..
        -- 'label[0,'.. iy+1.5 ..';'..S('Nametag Color')..']' ..
        -- 'dropdown[0,'.. iy+2 ..';'..fw..';nametag_color;<item 1>,<item 2>,<item n>;1]' ..

        'label[0,'.. iy+3 ..';'..S('Texture')..']' ..
        'dropdown[0,'.. iy+3.5 ..';'..fw..';texture;'..dv.texture..';'..ti..']' ..

        -- 'field[0.3,'.. iy+5 ..';'..fw..',0.3;wield_item;'..S('wield_item')..';'..dv.wield_item..']' ..
        --~ 'button[0.1,2;2,1;form01;'..S('Look')..']' ..
        --~ 'button[0.1,3;2,1;form01;'..S('Actions')..']' ..
        -- 'button[0,'.. iy+5 ..';'..fw..',0.5;action;'..S('configurer les interactions')..']' ..
        'button_exit['.. ww - 1 ..','.. wh - 1 ..';1,1;ok;ok]'..
        ''

    forms[2] = 
		default.gui_slots ..
		"list[nodemeta:" .. spos .. ";main;0,0.3;8,4;]" ..
		"list[current_player;main;0,4.85;8,1;]" ..
		"list[current_player;main;0,6.08;8,3;8]" ..
		"listring[nodemeta:" .. spos .. ";main]" ..
		"listring[current_player;main]" ..
		default.get_hotbar_bg(0,4.85) ..
        ''
        

    -- local action_buttons=''
    -- local l = 0.1
    -- for k,v in pairs(mobs.npcs.interactions) do
        -- action_buttons = action_buttons..'image_button['..l..',0;1,1;'..v.icon..';'..k..';]'
        -- l = l + 1
    -- end
    local acts={}
    for k,v in pairs(mobs.npcs.interactions) do
        if not ( v.disabled or v.hidden ) then
            acts[#acts+1] = k
        end
    end

    local action = data.action or {}
    if not data.action then data.action = {} end
    action.id = data.action.id or  "default"
    action.desc = mobs.npcs.interactions[action.id].desc
    
    local actstr=table.concat(acts,',')
    local ai = find_in_array(action.id,acts) or 1
    local actionf = ''
    local ayi = iy+2
    local action_arr = mobs.npcs.interactions[action.id]
    if action_arr and action_arr.formfields then
        for _,v in ipairs(action_arr.formfields) do
            if v[1] == 'label' then
                actionf = actionf .. 'label[0,'.. ayi ..';'..v[2]..']'
                ayi = ayi + 0.5
            elseif v[1] == 'textarea' then
	            -- {'textarea','message_cooldown','',2},
                local aname = v[2] 
                local dstr = action_arr[aname] or S("Hello").."\n"..S("Hi").."\n"..S("Hey")
                actionf = actionf .. 'textarea[0.3,'.. ayi ..';'..fw..','..v[4]..';action_'..v[2]..';'..v[3]..';'..dstr..']'
			   -- print(dump(actionf))
                ayi = ayi + v[4] + 0.1
            end
        end
    end
    forms[3] = 
        'label[0,'.. iy-0.5 ..';'..S('When a player interact with this character :')..']' ..
        'dropdown[0,'.. iy+0.5 ..';'..fw..';action_id;'..actstr..';'..ai..']' ..
        'label[0,'.. iy+1.5 ..';'..action.desc..']' ..
        actionf..
        -- textlist[<X>,<Y>;<W>,<H>;<name>;<listelem 1>,<listelem 2>,...,<listelem n>;<selected idx>;<transparent>]
        -- 'textlist[0,0;'..ww - 3*(ww/4)..','.. wh-1 ..';stagelist;action_1,stage_2,stage_3;1;false]'..
        -- 'container['..ww - 3*(ww/4)..',0]'..
        -- image_button[<X>,<Y>;<W>,<H>;<texture name>;<name>;<label>]
        -- 'image_button[0.1,0;1,1;'..icprefix..'chat.png^'..icprefix..'selected.png'..';act1;]'..
        -- action_buttons ..
        
        
        -- 'container_end[]'..
        -- 'button[0,'.. wh-1 ..';1,1;add_stage;+]'..
        -- 'button[1,'.. wh-1 ..';1,1;help_stage;?]'..
        'button_exit['.. ww - 1 ..','.. wh - 1 ..';1,1;ok;ok]'..
        ''
        
    forms[4] = 
        'textarea[0.3,'.. iy+1.6 ..';'..fw..',1.6;infotext;'..S('InfoText')..';'..dv.infotext..']'..
		'button_exit['.. ww - 1 ..','.. wh - 1 ..';1,1;ok;ok]'..
        ''






    local content = forms[n] or ''


	local formspec =
		'size['..ww..','..wh..']' ..
        -- default.gui_bg ..
		-- default.gui_bg_img ..
        'field[-1,-1;0,0.5;key;;'..minetest.pos_to_string(pos)..']' ..
        'tabheader[0,'.. iy - 0.5  ..';tab;Apparence,Inventaire,Action,Misc;'..    n..';false;false]'..
        content..
    -- tabheader[<X>,<Y>;<name>;<caption 1>,<caption 2>,...,<caption n>;<current_tab>;<transparent>;<draw_border>]
		

		--~ default.get_hotbar_bg(0,4.85)
        --~ button[<X>,<Y>;<W>,<H>;<name>;<label>]
        --~ field[<X>,<Y>;<W>,<H>;<name>;<label>;<default>]
        --~ textarea[<X>,<Y>;<W>,<H>;<name>;<label>;<default>]
        --~ label[<X>,<Y>;<label>]
        --~ dropdown[<X>,<Y>;<W>;<name>;<item 1>,<item 2>, ...,<item n>;<selected idx>]
        
        -- 'button_exit['.. ww - 1 ..',0;1,1;close;x]'..
        ''
	return formspec
end



-- Function to initialize spawner : add entity and update metadata
-- Called after place node and on rightclick



mobs.npcs.update_cmob_properties = function(pos, player, mob)
    
    minetest.log(vlog, '['..modname..'] '..'Updating mob properties from data at '..minetest.pos_to_string(pos))
    local data = get_mob_data(pos) or {}

    if data.obj and not mob then mob = data.obj end
    
    --- -- FIXEME: Seem to return true even when entity isn't there
	--- -- Probably because it's there just before being removed by the do_custom funtion
    local self
    if mob then self = mob:get_luaentity() end
    if not self then return false end
    
    -- mob:set_pos({ x= pos.x, y= pos.y + 1, z= pos.z, })
    minetest.log(vlog, '['..modname..'] '..'Mob entity exist')


    -- print(dump(data))

    -- Set owner
    -- TODO: check that node is the correct node
    local player_name
    if not player then
		player_name = data.owner
    else
		player_name = player:get_player_name()
    end
    -- Set node meta
    local meta = minetest.get_meta(pos)
    local owner_name = data.owner or player_name
    meta:set_string("owner", owner_name)

    -- Set mob properties
    -- print(dump(self))

    if data.nametag then
        mob:set_nametag_attributes({
            color = data.nametag_color or 'green',
            text = data.nametag,
        })
    end
            
    mob:set_properties({ 
        infotext = data.infotext or nil,
        owner = owner_name,
        textures = data.textures or self.textures,
        infotext = data.infotext or self.infotext,
        wield_item = data.wield_item or self.wield_item,
        visual_size = data.visual_size or self.visual_size,
    })
	-- self = mob:get_luaentity()
    self._mobname = data.nametag or nil
    self._owner = owner_name
    self._spawner_pos = pos
    
    data.obj = mob
    -- Register to global table
    set_mob_data(pos,data)
   
    -- print(dump(self))

end

mobs.npcs.update_cmob_data = function(pos)

    minetest.log(vlog, '['..modname..'] '..'Updating mob data from current properties at '..minetest.pos_to_string(pos))

    local data = get_mob_data(pos)

    if data and data.obj then
        minetest.log(vlog, '['..modname..'] '..'Mob data exist')

        local self = data.obj:get_luaentity()
        -- If self is nil, the mob isn't there anymore...
        if not self then return false end
        minetest.log(vlog, '['..modname..'] '..'Mob entity too')

        local prop = data.obj:get_properties() or {}
        -- print(dump(prop))

        data.nametag = prop.nametag or nil
        data.nametag_color = prop.nametag_color or 'green'
        data.owner = prop.owner
        data.textures = prop.textures or self.textures
        data.infotext = prop.infotext or nil
        data.spawner_pos = pos
        data.wield_item = prop.wield_item or nil
        data.visual_size = prop.visual_size or nil

    end

    set_mob_data(pos,data)
    return data
end

mobs.npcs.add_cmob = function(pos, player, _)

    minetest.log(vlog, '['..modname..'] '..'Adding new mob at :'..minetest.pos_to_string(pos))

    -- Place mob
    local above = { x=pos.x, y=pos.y+1, z=pos.z }
    local mob = minetest.add_entity(above, modname..':'..mob_name,minetest.write_json({_spawner_pos = pos}))

    mobs.npcs.update_cmob_properties(pos, player, mob)
    mobs.npcs.update_cmob_data(pos)
    -- Get Data
    --~ local data = {}
    --~ data.nametag =  meta:get_string('npc_nametag')
    --~ data.nametag_color =  meta:get_string('npc_nametag_color')
    
    -- Apply it to the mob
    --~ local self = mob:get_luaentity()
    --~ mob:set_properties({ 
        --~ owner = owner,
        --~ _spawner_pos = pos,
        --~ })
    --~ if data.nametag then 
        --~ if not data.nametag_color then data.nametag_color = 'green' end
        --~ mob:set_nametag_attributes({
            --~ color = data.nametag_color,
            --~ text = data.nametag,
        --~ })
    --~ end
    
end


local function cmob_data_update(pos,player,itemstack,mob,playername)

	-- Update mob properties
	mobs.npcs.update_cmob_properties(pos, player, mob)
	local data = mobs.npcs.update_cmob_data(pos)
				
	local meta = minetest.get_meta(pos)
	local owner = meta:get_string('owner') 

	-- Re-call the after_place_node function if needed
	if not ( data and data.obj ) then
		
		 -- Get infos about the owner
		local powner = minetest.get_player_by_name(owner)
		if player and (not powner) then
			powner = player
		end
		
		
		-- Call the function 
		--~ local spw_init = minetest.registered_nodes[node.name].after_place_node
		--~ if spw_init and player then
			--~ spw_init(pos, player, itemstack)
		--~ end
		for _,obj in ipairs(minetest.get_objects_inside_radius(pos, 1)) do
			if obj:get_luaentity().name == mob_id then
				obj:remove()
			end
		end
		mobs.npcs.add_cmob(pos, powner, itemstack)                
	end

	return data
end

local function cmob_show_formspec(pos,player,data)
	local tab = 1
	if data and data.last_tab then
		tab = data.last_tab
	end 
	minetest.after(0.2, 
			minetest.show_formspec,
			player:get_player_name(),
			modname..':'..mob_name..'_form0'..tab,
			get_npc_formspec(pos,tab))
end
--
-- Register Npc
--

mob_def.walk_chance = 0
mob_def.jump = false
local dtstep = 15
local dt = 0
mob_def.do_custom = function(self, dtime)

	-- Save memory by runing only 1/dtstep times
	if dt < dtstep then 
		dt = dt + 1
		return false
	else
		dt = 0
	end
	
	
	-- Make sure that cooldown is a number
	if type(self._cooldown) ~= 'number'
		or self._cooldown <= 0 
		then 
		self._cooldown = 0
	-- Cooldown if needed
	else
		self._cooldown = self._cooldown - ( dtstep * dtime )
		-- print('Cooldown : '..dump(self._cooldown))
	end

	--- Get mob pos
	local pos = self.object:get_pos()
	local spawner_pos = self._spawner_pos
	
	--- Look for reasons to remove the mob:
	--- Spawner pos is not set...
	--- ... try to find it
	-- if not spawner_pos then 	
		-- for i=-1,1 do
			-- local spos = { x= pos.x, y= pos.y + i, z= pos.z, } 
			-- if ( minetest.get_node(spos).name == spawner_id ) then
				-- spawner_pos = spos
				-- break
			-- end
		-- end
	-- end
	
	--- Spawner pos is not set...
	if ( not spawner_pos )	
	--- Or mob is away from spawner 
	 or ( vector.distance(pos, spawner_pos) > 1 )
	--- Or spawner has been removed
	 or ( minetest.get_node(spawner_pos).name ~= spawner_id )
	 then
		self.object:remove()
		return false
	end

	-- local meta = minetest.get_meta(spawner_pos)
	local data = get_mob_data(spawner_pos)
	if not data.obj then 
		self.object:remove()
		mobs.npcs.add_cmob(spawner_pos, data.owner) 
	end
	-- set_mob_data(spawner_pos,data)
	-- mobs.npcs.update_cmob_properties(spawner_pos, nil, self.obj)
	
	-- Make sure that it is still on the spawner (or at least 'in' it, or 'above' it)
	-- for i=-1,1 do
		-- local spos = { x= pos.x, y= pos.y + i, z= pos.z, } 
		-- if ( minetest.get_node(spos).name == spawner_id ) then
			-- --- Stop function when spawner is found
			-- mobs.npcs.update_cmob_properties(pos, nil, self.obj)
			-- return false
		-- end
	-- end
	
	-- Remove mob if it is away from spawner
	-- self.object:remove()
	return false
end

-- Set on_right_click interaction
mob_def.on_rightclick = function(self, clicker)

    -- Look at the player
    mobs.npcs.turn_to_player(self, clicker)

    -- Find spawner 
    local spawner_pos = self._spawner_pos    

    -- Edit and update
    local edit_key = 'sneak'
	if spawner_pos and clicker:get_player_control()[edit_key] then
		data = cmob_data_update(spawner_pos,clicker,nil,self.object)	
		cmob_show_formspec(spawner_pos,clicker,data)
		return
	end

    if spawner_pos then 
        -- Do custom action
        local data = get_mob_data(spawner_pos) or {}
        if data.action and data.action.id then
            local id = data.action.id
            local ref = mobs.npcs.interactions
            if ref[id] and ref[id].on_rightclick then
               return ref[id].on_rightclick(self, clicker, data)
            end
        end
    end

    -- Or at least say something
    local mobname = mobs.npcs.get_mobname(self)
    local clickername = clicker:get_player_name()
    local msg = mobs.npcs.messages.get_random()
    mobs.npcs.send_chat_message(clickername,msg,mobname)
    
end


mob_def.after_activate =  function(self, staticdata, def, dtime)
	-- Update mob after activate
	local pos = self._spawner_pos
	if pos then	
		local playername, player
		if self._owner then
			playername = self._owner
			player = minetest.get_player_by_name(playername)
		end
		local mob = self.object
		cmob_data_update(pos,player,nil,mob)
	end
end

mobs:register_mob(mob_id, mob_def)
    
-- This one doesn't spawn naturally, instead it spawn
minetest.register_node(spawner_id, {
		description = 'Place this to spawn a configurable npc',
		drawtype = "nodebox",
		tiles = {"default_stone_block.png"},
		paramtype = "light",
		paramtype2 = "facedir",
		is_ground_content = false,
		groups = {oddly_breakable_by_hand = 2},
		sounds = default.node_sound_stone_defaults(),
		node_box = {
			type = "fixed",
			fixed = {-0.5, -0.48, -0.5, 0.5, -0.5, 0.5},
		},
        on_construct = function(pos)
            -- minetest.get_node_timer(pos):start(20)
			local meta = minetest.get_meta(pos)
			-- meta:set_string("infotext", "Chest")
			local inv = meta:get_inventory()
			inv:set_size("main", 8*3)
	    end,

		after_place_node = mobs.npcs.add_cmob,
        
        --~ after_dig_node = function(pos, node, metadata, digger)
            --~ mobs.npcs.remove_custom_mob(pos, placer)
        --~ end,
        can_dig = function(pos,player)
			local meta = minetest.get_meta(pos);
			local inv = meta:get_inventory()
			return inv:is_empty("main") and default.can_interact_with_node(player, pos)
		end,
        on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)

            -- --
            -- Check that the npc is still there
            -- --
            local data = cmob_data_update(pos, clicker, itemstack)
            
            -- --
            -- Stop there if not allowed to interact
            -- --
            if not default.can_interact_with_node(clicker, pos) then
                return itemstack
            end

            -- Show customisation form
			cmob_show_formspec(pos,clicker,data)
        end,

        -- on_receive_fields = function(pos, formname, fields, sender)
        -- end
})


-- Register egg
-- mobs:register_egg(mob_id, "npc", "character_lambda_inv.png", 0)
--~ mobs:doc_identifier_compat(mob_id, longdesc, usagehelp)

mobs:alias_mob("mobs:"..mob_name, mob_id) -- compatibility

local on_receive_fields = function(player, formname, fields)
        
    local playername = player:get_player_name()
    
    if not string.match(formname, modname..':'..mob_name..'_form0%d') then
        return false
    end
    -- print('-------- FIELDS ------------')
    -- print(dump(fields))

    local pos
    if fields.key then
        pos = minetest.string_to_pos(fields.key)
    end
    
    if not pos then return false end
    local data = get_mob_data(pos) or {}
    
    -- Update data without overiding it
    if fields.texture then data.textures = { fields.texture } end
    if fields.action_id then 
    -- if fields.action_id and (( not data.action ) or ( fields.action_id ~= data.action.id )) then 
        data.action = data.action or {}
        -- data.action.id = fields.action_id
        -- data.action.message = fields.action_message or data.action.message
        -- data.action = mobs.npcs.interactions[fields.action_id]
        for k,v in pairs(fields) do
            for l in string.gmatch(k,"action_([A-Za-z0-9_]+)") do
                -- print('action '..dump(l)..' : '..dump(v))
                data.action[l] = v or data.action[l]
            end
        end
    end
    local fk = {
        'nametag','nametag_color','allowed','infotext','wield_item',
    }
    for _,v in ipairs(fk) do
        if fields[v] then data[v] = fields[v] end
    end
    data.last_tab = fields.tab or data.last_tab
    
    -- data.visual_size = {x = 1, y = 1.1}
    
	-- print('-------- DATA ------------')
	-- print(dump(data))

    set_mob_data(pos,data)
    mobs.npcs.update_cmob_properties(pos,player,data.obj)
    
    local tb = data.last_tab
    if ( fields.tab or fields.action_id ) and not fields.quit then 
        minetest.after(0.2, 
            minetest.show_formspec,
            playername,
            modname..':'..mob_name..'_form0'..tb,
            get_npc_formspec(pos,tb))
 
    end

        
end

minetest.register_on_player_receive_fields(on_receive_fields)