From c4bad91b8c61aa038ebccda1ba29b0e89b3e2685 Mon Sep 17 00:00:00 2001
From: cora <coradelamouche@gmx.ch>
Date: Fri, 23 Sep 2022 05:41:52 +0200
Subject: [PATCH] Add entity inventories

---
 mods/ENTITIES/mcl_entity_invs/api.txt  |  8 +++
 mods/ENTITIES/mcl_entity_invs/init.lua | 90 ++++++++++++++++++++++++++
 mods/ENTITIES/mcl_entity_invs/mod.conf |  3 +
 3 files changed, 101 insertions(+)
 create mode 100644 mods/ENTITIES/mcl_entity_invs/api.txt
 create mode 100644 mods/ENTITIES/mcl_entity_invs/init.lua
 create mode 100644 mods/ENTITIES/mcl_entity_invs/mod.conf

diff --git a/mods/ENTITIES/mcl_entity_invs/api.txt b/mods/ENTITIES/mcl_entity_invs/api.txt
new file mode 100644
index 000000000..4bfc66c3b
--- /dev/null
+++ b/mods/ENTITIES/mcl_entity_invs/api.txt
@@ -0,0 +1,8 @@
+mcl_entity_invs
+===============
+
+Inventories for your entities. It's simple. Depend on mcl_entity_invs and register your entity like so:
+
+* mcl_entity_invs.register_inv("entity:name","Title shown in formspec",inventory_size)
+
+It works by setting up a detached inventory per entity which is accessed by an id/hash generated from the entities position at creation, the progressed gametime at creation and a random salt.
diff --git a/mods/ENTITIES/mcl_entity_invs/init.lua b/mods/ENTITIES/mcl_entity_invs/init.lua
new file mode 100644
index 000000000..52ee636f3
--- /dev/null
+++ b/mods/ENTITIES/mcl_entity_invs/init.lua
@@ -0,0 +1,90 @@
+mcl_entity_invs = {}
+
+local function check_distance(inv,player,count)
+	for _,o in pairs(minetest.get_objects_inside_radius(player:get_pos(),5)) do
+		local l = o:get_luaentity()
+		if l and l._inv_id and inv:get_location().name == l._inv_id then return count end
+	end
+	return 0
+end
+
+local inv_callbacks = {
+	allow_take = function(inv, listname, index, stack, player)
+		return check_distance(inv,player,stack:get_count())
+	end,
+	allow_move = function(inv, from_list, from_index, to_list, to_index, count, player)
+		return check_distance(inv,player,count)
+	end,
+	allow_put = function(inv, listname, index, stack, player)
+		return check_distance(inv,player,stack:get_count())
+	end,
+}
+
+local function load_inv(ent,size)
+	if not ent._inv_id then return end
+	local inv = minetest.get_inventory({type="detached", name=ent._inv_id})
+	if not inv then
+		inv =  minetest.create_detached_inventory(ent._inv_id, inv_callbacks)
+		inv:set_size("main", size)
+		if ent._items then
+			inv:set_list("main",ent._items)
+		end
+	end
+	return inv
+end
+
+local function show_form(ent,player,show_name)
+	if not ent._inv_id then return end
+	local playername = player:get_player_name()
+	local formspec = "size[9,8.75]"
+	.. "label[0,0;" .. minetest.formspec_escape(
+			minetest.colorize("#313131", show_name)) .. "]"
+	.. "list[detached:"..ent._inv_id..";main;0,0.5;9,3;]"
+	.. mcl_formspec.get_itemslot_bg(0,0.5,9,3)
+	.. "label[0,4.0;" .. minetest.formspec_escape(
+			minetest.colorize("#313131", "Inventory")) .. "]"
+	.. "list[current_player;main;0,4.5;9,3;9]"
+	.. mcl_formspec.get_itemslot_bg(0,4.5,9,3)
+	.. "list[current_player;main;0,7.74;9,1;]"
+	.. mcl_formspec.get_itemslot_bg(0,7.74,9,1)
+	.. "listring[detached:"..ent._inv_id..";main]"
+	.. "listring[current_player;main]"
+	minetest.show_formspec(playername,ent._inv_id,formspec)
+end
+
+function mcl_entity_invs.register_inv(entity_name,show_name,size)
+	local old_oa = minetest.registered_entities[entity_name].on_activate
+	minetest.registered_entities[entity_name].on_activate  = function(self,staticdata,dtime_s)
+		local d = minetest.deserialize(staticdata)
+		if type(d) == "table" and d._inv_id then
+			self._inv_id = d._inv_id
+			self._items = d._items
+		else
+			self._inv_id="entity_inv_"..minetest.sha1(minetest.get_gametime()..minetest.pos_to_string(self.object:get_pos())..tostring(math.random()))
+			--gametime and position for collision safety and math.random salt to protect against position brute-force
+		end
+		if self._inv_id then
+			self._inv = load_inv(self,size)
+		end
+		if old_oa then return old_oa(self,clicker) end
+	end
+
+	local old_rc = minetest.registered_entities[entity_name].on_rightclick
+	minetest.registered_entities[entity_name].on_rightclick = function(self,clicker)
+		show_form(self,clicker,show_name)
+		if old_rc then return old_rc(self,clicker) end
+	end
+	local old_gsd = minetest.registered_entities[entity_name].get_staticdata
+	minetest.registered_entities[entity_name].get_staticdata  = function(self)
+		local old_sd = old_gsd(self)
+		local d = minetest.deserialize(old_sd)
+		assert(type(d) == "table","Entyinvs currently only works with entities that return a (serialized) table in get_staticdata. "..tostring(self.name).." returned: "..tostring(old_sd))
+		d._inv_id = self._inv_id
+		d._items = {}
+		for i,it in pairs(self._inv:get_list("main")) do
+			d._items[i] = it:to_string()
+		end
+		return minetest.serialize(d)
+	end
+
+end
diff --git a/mods/ENTITIES/mcl_entity_invs/mod.conf b/mods/ENTITIES/mcl_entity_invs/mod.conf
new file mode 100644
index 000000000..8e94d6b1e
--- /dev/null
+++ b/mods/ENTITIES/mcl_entity_invs/mod.conf
@@ -0,0 +1,3 @@
+name = mcl_entity_invs
+author = cora
+depends = mcl_formspec