Add selfaware functions for E2 extensions (#2823)

* Add selfaware functions for E2 extensions

* Optimize

* Lessons in futility

lua/entities/gmod_wire_expression2/core/selfaware.lua

@@ -203,6 +203,48 @@ e2function number entity:canSetName(string name)
 	return IsValid(this) and isOwner(self, this) and canSetName(self, this, name) and 1 or 0
 end
 
+--[[******************************************************************************]]--
+-- Extensions
+
+local getExtensionStatus = E2Lib.GetExtensionStatus
+local e2Extensions
+local e2ExtensionsTable
+-- See postinit for these getting initialized
+
+__e2setcost(30)
+
+[nodiscard]
+e2function array getExtensions()
+	local ret = {}
+	for k, v in ipairs(e2Extensions) do -- Optimized copy
+		ret[k] = v
+	end
+	return ret
+end
+
+__e2setcost(60)
+
+[nodiscard]
+e2function table getExtensionStatus()
+	local ret = E2Lib.newE2Table()
+	local s, stypes = ret.s, ret.stypes
+	ret.size = e2ExtensionsTable.size
+
+	for k, v in pairs(e2ExtensionsTable.s) do
+		s[k] = v
+		stypes[k] = "n"
+	end
+
+	return ret
+end
+
+__e2setcost(5)
+
+[nodiscard]
+e2function number getExtensionStatus(string extension)
+	return getExtensionStatus(extension) and 1 or 0
+end
+
 
 --[[******************************************************************************]]--
 
@@ -287,6 +329,18 @@ registerCallback("postinit", function()
 			end
 		end
 	end
+
+	e2Extensions = E2Lib.GetExtensions()
+	e2ExtensionsTable = E2Lib.newE2Table()
+	do
+		local s, stypes, size = e2ExtensionsTable.s, e2ExtensionsTable.stypes, 0
+		for _, ext in ipairs(e2Extensions) do
+			s[ext] = getExtensionStatus(ext) and 1 or 0
+			stypes[ext] = "n"
+			size = size + 1
+		end
+		e2ExtensionsTable.size = size
+	end
 end)
 
 --[[******************************************************************************]]--

lua/wire/client/e2descriptions.lua

@@ -908,6 +908,9 @@ E2Helper.Descriptions["ioOutputEntities(s)"] = "Returns an array of all entities
 E2Helper.Descriptions["runOnLast(n)"] = "If set to 1, the chip will run once when it is removed, setting the last() flag when it does"
 E2Helper.Descriptions["selfDestruct()"] = "Removes the expression"
 E2Helper.Descriptions["selfDestructAll()"] = "Removes the expression and all constrained props"
+E2Helper.Descriptions["getExtensions()"] = "Returns an array of all the extensions that the server has. This includes disabled extensions!"
+E2Helper.Descriptions["getExtensionStatus()"] = "Returns a table of extension names with their statuses"
+E2Helper.Descriptions["getExtensionStatus(s)"] = "Returns 1 if the extension is enabled, otherwise 0"
 
 -- Debug
 E2Helper.Descriptions["playerCanPrint()"] = "Returns whether or not the next print-message will be printed or omitted by antispam"