Merge plugin back into main repository (#49)

plugin/src/RouteMap.lua

@@ -0,0 +1,103 @@
+--[[
+	A map from Route objects (given by the server) to Roblox instances (created
+	by the plugin).
+]]
+
+local function hashRoute(route)
+	return table.concat(route, "/")
+end
+
+local RouteMap = {}
+RouteMap.__index = RouteMap
+
+function RouteMap.new()
+	local self = {
+		_map = {},
+		_reverseMap = {},
+		_connectionsByRbx = {},
+	}
+
+	setmetatable(self, RouteMap)
+
+	return self
+end
+
+function RouteMap:insert(route, rbx)
+	local hashed = hashRoute(route)
+
+	self._map[hashed] = rbx
+	self._reverseMap[rbx] = hashed
+	self._connectionsByRbx[rbx] = rbx.AncestryChanged:Connect(function(_, parent)
+		if parent == nil then
+			self:removeByRbx(rbx)
+		end
+	end)
+end
+
+function RouteMap:get(route)
+	return self._map[hashRoute(route)]
+end
+
+function RouteMap:removeByRoute(route)
+	local hashedRoute = hashRoute(route)
+	local rbx = self._map[hashedRoute]
+
+	if rbx then
+		self._map[hashedRoute] = nil
+		self._reverseMap[rbx] = nil
+		self._connectionsByRbx[rbx] = nil
+	end
+end
+
+function RouteMap:removeByRbx(rbx)
+	local hashedRoute = self._reverseMap[rbx]
+
+	if hashedRoute then
+		self._map[hashedRoute] = nil
+		self._reverseMap[rbx] = nil
+		self._connectionsByRbx[rbx] = nil
+	end
+end
+
+function RouteMap:removeRbxDescendants(parentRbx)
+	for rbx in pairs(self._reverseMap) do
+		if rbx:IsDescendantOf(parentRbx) then
+			self:removeByRbx(rbx)
+		end
+	end
+end
+
+function RouteMap:clear()
+	self._map = {}
+	self._reverseMap = {}
+
+	for object in pairs(self._connectionsByRbx) do
+		object:Disconnect()
+	end
+
+	self._connectionsByRbx = {}
+end
+
+function RouteMap:visualize()
+	-- Log all of our keys so that the visualization has a stable order.
+	local keys = {}
+
+	for key in pairs(self._map) do
+		table.insert(keys, key)
+	end
+
+	table.sort(keys)
+
+	local buffer = {}
+	for _, key in ipairs(keys) do
+		local visualized = ("- %s: %s"):format(
+			key,
+			self._map[key]:GetFullName()
+		)
+		table.insert(buffer, visualized)
+	end
+
+	return table.concat(buffer, "\n")
+end
+
+return RouteMap