1 files changed, 68 insertions, 0 deletions
diff --git a/worldedit_commands/safe.lua b/worldedit_commands/safe.lua
new file mode 100644
index 0000000..e640853
--- /dev/null
+++ b/worldedit_commands/safe.lua
@@ -0,0 +1,68 @@
+local safe_region_callback = {}
+local safe_region_param = {}
+
+local function check_region(name, param)
+	local pos1, pos2 = worldedit.pos1[name], worldedit.pos2[name] --obtain positions
+	if pos1 == nil or pos2 == nil then
+		worldedit.player_notify(name, "no region selected")
+		return nil
+	end
+	return worldedit.volume(pos1, pos2)
+end
+
+--`callback` is a callback to run when the user confirms
+--`nodes_needed` is a function accepting `param`, `pos1`, and `pos2` to calculate the number of nodes needed
+local function safe_region(callback, nodes_needed)
+	--default node volume calculation
+	nodes_needed = nodes_needed or check_region
+
+	return function(name, param)
+		--check if the operation applies to a safe number of nodes
+		local count = nodes_needed(name, param)
+		if count == nil then return end --invalid command
+		if count < 10000 then
+			return callback(name, param)
+		end
+
+		--save callback to call later
+		safe_region_callback[name], safe_region_param[name] = callback, param
+		worldedit.player_notify(name, "WARNING: this operation could affect up to " .. count .. " nodes; type //y to continue or //n to cancel")
+	end
+end
+
+minetest.register_chatcommand("/y", {
+	params = "",
+	description = "Confirm a pending operation",
+	func = function(name)
+		local callback, param = safe_region_callback[name], safe_region_param[name]
+		if not callback then
+			worldedit.player_notify(name, "no operation pending")
+			return
+		end
+
+		--obtain positions
+		local pos1, pos2 = worldedit.pos1[name], worldedit.pos2[name]
+		if pos1 == nil or pos2 == nil then
+			worldedit.player_notify(name, "no region selected")
+			return
+		end
+
+		safe_region_callback[name], safe_region_param[name] = nil, nil --reset pending operation
+		callback(name, param, pos1, pos2)
+	end,
+})
+
+minetest.register_chatcommand("/n", {
+	params = "",
+	description = "Confirm a pending operation",
+	func = function(name)
+		if not safe_region_callback[name] then
+			worldedit.player_notify(name, "no operation pending")
+			return
+		end
+		safe_region_callback[name], safe_region_param[name] = nil, nil
+	end,
+})
+
+return safe_region, check_region
+