From e486a1ba6421c62bf3bf1a4c54cad9451d44d051 Mon Sep 17 00:00:00 2001
From: BuckarooBanzay <BuckarooBanzay@users.noreply.github.com>
Date: Fri, 15 Mar 2024 08:04:00 +0100
Subject: [PATCH] add `pick_and_place.register_on_deserialize`

---
 readme.md     | 15 +++++++++++++++
 serialize.lua | 12 ++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/readme.md b/readme.md
index cdd3b24..8c16b8e 100644
--- a/readme.md
+++ b/readme.md
@@ -57,6 +57,21 @@ If you pick-and-place a replacement node the default node-placement is replaced
 Grid-snapping can be enabled with `/pnp_snap on` while holding a place-tool.
 Disabling it can be done with `/pnp_snap off`
 
+# Modding api
+
+## pick_and_place.register_on_deserialize(fn)
+
+register a function callback for after deserialization
+
+```lua
+local mynodeid = minetest.get_content_id("my:node")
+pick_and_place.register_on_deserialize(function(pos1, pos2, nodeids)
+ if nodeids[mynodeid] then
+  -- nodeid matches, do something after the schematic has been placed into the world
+ end
+end)
+```
+
 # Portability
 
 The placement tool can be shared across worlds if the nodes are available there.
diff --git a/serialize.lua b/serialize.lua
index 6f27dd6..5eec759 100644
--- a/serialize.lua
+++ b/serialize.lua
@@ -51,6 +51,8 @@ function pick_and_place.serialize(pos1, pos2)
     }
 end
 
+-- table: fn(pos1, pos2, node_ids)
+local deserialization_callbacks = {}
 
 function pick_and_place.deserialize(pos1, schematic, disable_replacements)
     local pos2 = vector.add(pos1, vector.subtract(schematic.size, 1))
@@ -61,6 +63,7 @@ function pick_and_place.deserialize(pos1, schematic, disable_replacements)
 
     local node_data = manip:get_data()
 	local param2 = manip:get_param2_data()
+    local node_ids = {}
 
     local ctx = {}
     local j = 1
@@ -69,6 +72,7 @@ function pick_and_place.deserialize(pos1, schematic, disable_replacements)
     for x=pos1.x,pos2.x do
         local i = area:index(x,y,z)
         local nodeid = schematic.node_id_data[j]
+        node_ids[nodeid] = true
 
         if nodeid == replacement_cid and not disable_replacements then
             -- replacement placement
@@ -107,5 +111,13 @@ function pick_and_place.deserialize(pos1, schematic, disable_replacements)
     manip:set_param2_data(param2)
     manip:write_to_map()
 
+    for _, fn in ipairs(deserialization_callbacks) do
+        fn(pos1, pos2, node_ids)
+    end
+
     return true
 end
+
+function pick_and_place.register_on_deserialize(fn)
+    table.insert(deserialization_callbacks, fn)
+end
\ No newline at end of file