From a175aa93e7185d929a471ac0ec4173e78be564cf Mon Sep 17 00:00:00 2001
From: CaitSith2 <d_good@caitsith2.com>
Date: Fri, 26 Aug 2022 01:31:30 -0700
Subject: [PATCH] Factorio: Detect if more than one AP factorio mod is loaded.
 (#964)

---
 worlds/factorio/data/mod_template/settings.lua | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/worlds/factorio/data/mod_template/settings.lua b/worlds/factorio/data/mod_template/settings.lua
index 7703ebe2..73e131a6 100644
--- a/worlds/factorio/data/mod_template/settings.lua
+++ b/worlds/factorio/data/mod_template/settings.lua
@@ -1,3 +1,21 @@
+-- Find out if more than one AP mod is loaded, and if so, error out.
+function mod_is_AP(str)
+    -- lua string.match is way more restrictive than regex. Regex would be "^AP-W?\d{20}-P[1-9]\d*-.+$"
+	local result = string.match(str, "^AP%-W?%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%-P[1-9]%d-%-.+$")
+	if result ~= nil then
+		log("Archipelago Mod: " .. result .. " is loaded.")
+	end
+	return result ~= nil
+end
+local ap_mod_count = 0
+for name, _ in pairs(mods) do
+    if mod_is_AP(name) then
+        ap_mod_count = ap_mod_count + 1
+        if ap_mod_count > 1 then
+            error("More than one Archipelago Factorio mod is loaded.")
+        end
+    end
+end
 data:extend({
     {
         type = "bool-setting",