SmartRoute: Implement auto route search and first prototype

1 files changed, 149 insertions, 0 deletions

diff --git a/advtrains_interlocking/smartroute.lua b/advtrains_interlocking/smartroute.lua
new file mode 100644
index 0000000..770c379
--- /dev/null
+++ b/advtrains_interlocking/smartroute.lua
@@ -0,0 +1,149 @@
+-- smartroute.lua
+-- Implementation of the advtrains auto-route search
+
+local atil = advtrains.interlocking
+local ildb = atil.db
+local sr = {}
+
+
+local function otherside(s)
+	if s==1 then return 2 else return 1 end
+end
+
+--route search implementation
+-- Note this is similar to recursively_find_routes in database.lua, there used for the rscache
+
+local function recursively_find_routes(s_pos, s_connid, searching_shunt, tcbseq, mark_pos, result_table, scan_limit)
+	--atdebug("Recursively restarting at ",s_pos, s_connid, "limit left", scan_limit)
+	local ti = advtrains.get_track_iterator(s_pos, s_connid, scan_limit, false)
+	local pos, connid, bconnid = ti:next_branch()
+	pos, connid, bconnid = ti:next_track()-- step once to get ahead of previous turnout
+	local last_pos
+	repeat
+		-- record position in mark_pos
+		local pts = advtrains.encode_pos(pos)
+		mark_pos[pts] = true
+		
+		local node = advtrains.ndb.get_node_or_nil(pos)
+		atdebug("(SmartRoute) Walk ",pos, "nodename", node.name, "entering at conn",bconnid)
+		local ndef = minetest.registered_nodes[node.name]
+		if ndef.advtrains and ndef.advtrains.node_state_map then
+			-- Stop, this is a switchable node. Find out which conns we can go at
+			atdebug("(SmartRoute) Found turnout ",pos, "nodename", node.name, "entering at conn",bconnid)
+			local out_conns = ildb.get_possible_out_connids(node.name, bconnid)
+			for oconnid, state in pairs(out_conns) do
+				--atdebug("Going in direction",oconnid,"state",state)
+				recursively_find_routes(pos, oconnid, searching_shunt, table.copy(tcbseq), table.copy(mark_pos), result_table, ti.limit)
+			end
+			return
+		end
+		--otherwise, this might be a tcb
+		local tcb = ildb.get_tcb(pos)
+		if tcb then
+			local fsigd = { p = pos, s = connid }
+			atdebug("(SmartRoute) Encounter TCB ",fsigd)
+			tcbseq[#tcbseq+1] = fsigd
+			-- check if this is a possible route endpoint
+			local tcbs = tcb[connid]
+			if tcbs.signal then
+				local ndef = advtrains.ndb.get_ndef(tcbs.signal)
+				if ndef and ndef.advtrains then
+					if ndef.advtrains.route_role == "main" or ndef.advtrains.route_role == "main_distant"
+							or ndef.advtrains.route_role == "end" or ndef.advtrains.route_role == "shunt" then
+						-- signal is suitable target
+						local is_mainsignal = ndef.advtrains.route_role ~= "shunt"
+						-- record the found route in the results
+						result_table[#result_table+1] = {
+							tcbseq = table.copy(tcbseq),
+							mark_pos = table.copy(mark_pos),
+							shunt_route = not is_mainsignal,
+							to_end_of_track = false,
+							name = tcbs.signal_name or atil.sigd_to_string(fsigd)
+						}
+						-- if this is a main signal and/or we are only searching shunt routes, stop the search here
+						if is_mainsignal or searching_shunt then
+							atdebug("(SmartRoute) Terminating here because it is main or only shunt routes searched")
+							return
+						end
+					end
+				end
+			end
+		end
+		-- Go forward
+		last_pos = pos
+		pos, connid, bconnid = ti:next_track()
+	until not pos -- this stops the loop when either the track end is reached or the limit is hit
+	--atdebug("recursively_find_routes: Reached track end or limit at", last_pos, ". This path is not saved, returning")
+end
+
+local function build_route_from_foundroute(froute, name)
+	local route = {
+		name = froute.name,
+		use_rscache = true,
+		smartroute_generated = true,
+	}
+	for _, sigd in ipairs(froute.tcbseq) do
+		route[#route+1] = { next = sigd, locks = {} }
+	end
+	return route
+end
+
+-- Maximum scan length for track iterator
+local TS_MAX_SCAN = 1000
+
+function sr.init(pname, sigd)
+	-- is start signal a shunt signal?
+	local is_startsignal_shunt = false
+	local tcbs = ildb.get_tcbs(sigd)
+	if tcbs.signal then
+		local ndef = advtrains.ndb.get_ndef(tcbs.signal)
+		if ndef and ndef.advtrains then
+			if ndef.advtrains.route_role == "shunt" then
+				is_startsignal_shunt = true
+			end
+		end
+	end
+	local result_table = {}
+	recursively_find_routes(sigd.p, sigd.s, is_startsignal_shunt, {}, {}, result_table, TS_MAX_SCAN)
+	
+	atdebug("Smartroute search finished:",result_table)
+	
+	-- Short-circuit logic right now for testing
+	-- go through and delete all routes that are autogenerated
+	local i = 1
+	while i<=#tcbs.routes do
+		if tcbs.routes[i].smartroute_generated then
+			table.remove(tcbs.routes, i)
+		else
+			i=i+1
+		end
+	end
+	-- just plainly create routes!
+	for idx, froute in ipairs(result_table) do
+		tcbs.routes[#tcbs.routes+1] = build_route_from_foundroute(froute)
+	end
+	atwarn("Smartroute done!")
+end
+
+
+
+--[[
+	player1 = {
+		origin = <sigd>
+		found_routes = {
+			{ tcbseq = {<sigd1>, <sigd2>, <end_sigd>}, mark_pos = { table with keys being encoded_pos of rails constituting route }, to_end_of_track = false, shunt_route = false }
+		}
+	}
+]]--
+local player_smartroute = {}
+
+minetest.register_on_punchnode(function(pos, node, player, pointed_thing)
+	local pname = player:get_player_name()
+	if not minetest.check_player_privs(pname, "interlocking") then
+		return
+	end
+	-- TODO
+end)
+
+
+advtrains.interlocking.smartroute = sr