-- based on my mobf_trader mod - but does not require any other mods


-- find out the right mesh; if the wrong one is used, the traders become invisible
npc_talk.talking_npc_mesh = "character.b3d";
-- 3darmor/wieldview is great
if( minetest.get_modpath( '3d_armor' )) then
	npc_talk.talking_npc_mesh = "3d_armor_character.b3d";
end
npc_talk.talking_npc_texture = "character.png"
npc_talk.talking_npc_inventory_image = "character.png"


-- look at the player
npc_talk.look_at_player = function(self, player)
	if(not(player) or not(self)) then
		return
	end
	-- look at the player
	local v1 = self.object:get_pos()
	local v2 = player:get_pos()
	local dx = v1.x - v2.x
	local dz = v2.z - v1.z
	self.object:set_yaw(math.atan2(dx, dz))
end


npc_talk.talking_npc_entity_prototype = {
	initial_properties = {
		-- so far, this is more or less the redefinition of the standard player model
		physical     = true,
		collisionbox = {-0.30, 0.0,-0.30, 0.30,1.8,0.30},
		visual       = "mesh";
		visual_size  = {x=1, y=1, z=1},
		mesh         = npc_talk.talking_npc_mesh,
		textures     = {npc_talk.talking_npc_texture},
		inventory_image = npc_talk.talking_npc_inventory_image,

		description  = 'Talking NPC (right-click to talk)',
		-- the NPC needs an owner
		owner = "",

	        armor_groups = {immortal=1},
		hp_max       = 100, -- just to be sure

		-- this mob only has to stand around and talk to players
		animation = {
			stand_START     =   0,
			stand_END       =  79,
			sit_START       =  81,
			sit_END         = 160,
			sleep_START     = 162,
			sleep_END       = 166,
			walk_START      = 168,
			walk_END        = 187,
			mine_START      = 189,
			mine_END        = 198,
			walkmine_START  = 200,
			walkmine_END    = 219,
		},
		animation_speed = 30,
	}, -- end of initial_properties

	get_staticdata = function(self)
		return npc_talk.talking_npc_get_staticdata(self)
	end,

	on_activate = function(self, staticdata, dtime)
		return npc_talk.talking_npc_on_activate(self, staticdata, dtime)
	end,

	-- actually talk to the NPC
	on_rightclick = function(self, clicker)
		npc_talk.look_at_player(self, clicker)
		return yl_speak_up.talk(self, clicker)
	end,
}

npc_talk.talking_npc_get_staticdata = function(self)
	-- taken basicly from mobs_redo
	local data = {}
	for _, v in pairs(self) do
		local t = type(v)
		if( t ~= "function" and t ~= "nil" and t ~= "userdata" and _ ~= "object" and _ ~= "_cmi_components") then
			data[_] = self[_]
		end
	end
	return minetest.serialize(data)
end


npc_talk.talking_npc_on_activate = function(self, staticdata, dtime)
	-- this is taken from mobs_redo and copies all staticdata to self
	local tmp = minetest.deserialize(staticdata)
	if tmp then
		for _,stat in pairs(tmp) do
			local t = type(stat)
			if t ~= "function" and t ~= "nil" and t ~= "userdata" then
				self[_] = stat
			end
		end
	end

	if(self.yl_speak_up) then
		-- set texture
		if(self.yl_speak_up.skin) then
			local tex = self.yl_speak_up.skin
			self.textures = {tex[1]}
		end
		-- set animation
		if(self.yl_speak_up.animation) then
			self.object:set_animation(self.yl_speak_up.animation)
		end
		-- set infotext
		if(yl_speak_up.infotext) then
			local i_text = ""
			if(self.yl_speak_up.npc_name) then
				i_text = i_text .. self.yl_speak_up.npc_name .. "\n"
			end
			if(self.yl_speak_up.npc_description) then
				i_text = i_text .. self.yl_speak_up.npc_description .. "\n"
			end
			i_text = i_text .. yl_speak_up.infotext
			self.infotext = i_text
		end
	end
	-- set anything changed above
	self.object:set_properties(self)
	-- the NPC is subject to gravity but does not move around
	self.object:set_velocity(    {x=0, y=  0, z=0})
	self.object:set_acceleration({x=0, y=-10, z=0})
	-- show the nametag (or not - depending on the mob's configuration)
	if(self.yl_speak_up) then
		yl_speak_up.update_nametag(self)
	end
end

-- the mob as entity
minetest.register_entity( "npc_talk:talking_npc", npc_talk.talking_npc_entity_prototype)


-- the mob as an item - carried in the inventory
-- If you want to add mobs with diffrent names/descriptions/inventory images/entities, just add your
-- own register_craftitem and use this as an example.
minetest.register_craftitem("npc_talk:talking_npc_item", {
	name            = "Talking NPC",
	description     = "Talking NPC. Place somewhere and right-click in order to talk to him.",
	groups          = {},
	stack_max       = 1,
	inventory_image = npc_talk.talking_npc_inventory_image,
	wield_image     = npc_talk.talking_npc_inventory_image,
	drawtype        = "mesh",
	mesh            = npc_talk.talking_npc_mesh,
	textures        = {npc_talk.talking_npc_texture},
	on_place        = function(itemstack, placer, pointed_thing)
				return npc_talk.talking_npc_on_place(itemstack, placer, pointed_thing)
			  end,
})


-- place the craftitem from your inventory to get the NPC entity in the world
npc_talk.talking_npc_on_place = function(itemstack, placer, pointed_thing)
	-- taken from mobs_redo
	local pos = pointed_thing.above
	-- does existing on_rightclick function exist?
	local under = minetest.get_node(pointed_thing.under)
	local def = minetest.registered_nodes[under.name]
	if(def and def.on_rightclick)then
		return def.on_rightclick(pointed_thing.under, under, placer, itemstack, pointed_thing)
	end
	if(pos and not minetest.is_protected(pos, placer:get_player_name())) then

		local mob = "npc_talk:talking_npc"
		pos.y = pos.y + 1
		local data_str = itemstack:get_metadata()
		local data = minetest.deserialize(data_str)
		local smob = minetest.add_entity(pos, mob, data)
		local ent = smob and smob:get_luaentity()
		if(not(ent)) then
			return
		end
		ent.owner = placer:get_player_name()
		ent.tamed = true
		itemstack:take_item()
	end
	return itemstack
end


npc_talk.talking_npc_pick_up = function(self, player)
	-- taken from/inspired by mobs_redo as well
	if(not(self) or not(player:is_player()) or not(player:get_inventory())) then
		return false
	end
	local pname = player:get_player_name()
	if(not(minetest.check_player_privs(pname, "protection_bypass"))
	  and self.owner ~= pname) then
		minetest.chat_send_player(pname, "This NPC is owned by "..tostring(self.owner or "?")..".")
		return false
	end
	local mobname = "npc_talk:talking_npc_item"
	if(not(player:get_inventory():room_for_item("main", mobname))) then
		minetest.chat_send_player(pname, "You have not enough room in your inventory.")
		return false
	end
	local stack = ItemStack(mobname)
	local data = minetest.serialize(npc_talk.talking_npc_get_staticdata(self))
	stack:set_metadata(data)
	local inv = player:get_inventory()
	if(inv:room_for_item("main", stack)) then
		inv:add_item("main", stack)
	else
		minetest.add_item(player:get_pos(), stack)
	end
	self.object:remove()
	return stack
end


-- add the necessary data for skin configuration etc.
npc_talk.enable_talk_to_talking_npc = function()
	-- the following information is needed in order to handle skin changes

	-- this model is used by mobs_npc
	yl_speak_up.mesh_data["character.b3d"] = {
		-- the first texture is the skin
		texture_index = 1,
		-- there is no support for capes or wielded items
		can_show_wielded_items = false,
		-- textures are applied directly
		textures_to_skin = false,
		-- this information needed so that the animation of the mob can be set (i.e. them sitting)
		animation = {
			-- {x = start_frame, y = end_frame, collisionbox}
			stand_still = {x =   0, y =   0, collisionbox = {-0.3, 0.0, -0.3, 0.3, 1.7, 0.3}},
			stand       = {x =   0, y =  79, collisionbox = {-0.3, 0.0, -0.3, 0.3, 1.7, 0.3}},
			sit         = {x =  81, y = 160, collisionbox = {-0.3, 0.0, -0.3, 0.3, 1.0, 0.3}},
			lay         = {x = 162, y = 166, collisionbox = {-0.6, 0.0, -0.6, 0.6, 0.3, 0.6}},
			walk        = {x = 168, y = 187, collisionbox = {-0.3, 0.0, -0.3, 0.3, 1.7, 0.3}},
			mine        = {x = 189, y = 198, collisionbox = {-0.3, 0.0, -0.3, 0.3, 1.7, 0.3}},
			walk_mine   = {x = 200, y = 219, collisionbox = {-0.3, 0.0, -0.3, 0.3, 1.7, 0.3}},
	        },
	}

	-- list all textures that shall be available as skins for this particular npc:
	-- the normal NPC (can be fed and tamed with bread)
	yl_speak_up.mob_skins["npc_talk:talking_npc"] = {
		npc_talk.talking_npc_texture,
		-- at least add some variety - even if we have no textures
		npc_talk.talking_npc_texture.."^[colorizehsl:0",
		npc_talk.talking_npc_texture.."^[colorizehsl:60",
		npc_talk.talking_npc_texture.."^[colorizehsl:120",
		npc_talk.talking_npc_texture.."^[colorizehsl:180",
		npc_talk.talking_npc_texture.."^[colorizehsl:-60",
		npc_talk.talking_npc_texture.."^[colorizehsl:-120",
		npc_talk.talking_npc_texture.."^[colorizehsl:-180",
		}


	yl_speak_up.add_on_rightclick_entry["npc_talk:talking_npc"] = {
		text_if_true     = "[Pick this NPC up.]",
		text_if_false    = "[Something wrent wrong. This is for picking the mob up.]",
		condition        = true,
		execute_function = npc_talk.talking_npc_pick_up,
	}
end


if(not(minetest.get_modpath("player_api"))) then
	minetest.log("warn", "[npc_talk] Optional dependency \"player_api\" not found. "..
			"NPC npc_talk:talking_npc will not work if there is no other mod "..
			"providing character.b3d and character.png.")
end


-- make sure the NPC can be configured regarding its skin
yl_speak_up.register_on_reload(npc_talk.enable_talk_to_talking_npc, "npc_talk.enable_talk_to_talking_npc()")