path: root/advtrains_interlocking/signal_api.lua

-- Signal API implementation

local F = advtrains.formspec

local signal = {}

signal.MASP_HALT = {
	name = "_halt",
	halt = true,
}

signal.MASP_DEFAULT = {
	name = "_default",
	default = true,
}

signal.ASPI_HALT = {
	main = 0,
	shunt = false,
}

signal.ASPI_FREE = {
	main = -1,
	shunt = false,
	proceed_as_main = true,
}

--[[
Implementation plan orwell 2024-01-28:
Most parts of ywang's implementation are fine, especially I like the formspecs. But I would like to change a few aspects (no pun intended) of this.
- Signal gets distant assigned via field in signal aspect table (instead of explicitly)
- Signal speed/shunt are no longer free-text but rather they need to be predefined in the node definition
To do this: Differentiation between:
== Main Aspect ==
This is what a signal is assigned by either the route system or the user.
It is a string key which has an appropriate entry in the node definition (where it has a description assigned)
The signal mod defines a function to set a signal to the most appropriate aspect. This function gets
a) the main aspect table (straight from node def)
b) the distant signal's aspect group name & aspect table

== Aspect ==
One concrete combination of lights/shapes that a signal signal shows. Handling these is at the discretion of
the signal mod defining the signal, and they are typically combinations of main aspect and distant aspect
Example:
- A Ks signal has the main_aspect="proceed_12" set for a route
- The signal at the end of the route shows main_aspect="proceed_8", advtrains also passes on that this means {main=8, shunt=false}
- The ndef.afunction(pos, node, main_aspect, rem_aspect, rem_aspinfo) determines that the signal should now show
		blinking green with main indicator 12 and dst indicator 8, and sets the nodes accordingly.
		This function can now return the Aspect Info table, which will be cached by advtrains until the aspect changes again
		and will be used when a train approaches the signal. If nil is returned, then the aspect will be queried next time
		by calling ndef.advtrains.get_aspect_info(pos)

Note that once apply_aspect returns, there is no need for advtrains anymore to query the aspect info.
When the signal, for any reason, wants to change its aspect by itself *without* going through the signal API then
it should update the aspect info cache by calling advtrains.interlocking.signal.update_aspect_info(pos)

Apply_aspect may also receive the special main aspect { name = "_halt", halt = true }. It usually means that the signal is not assigned to anything particular,
and it should cause the signal to show its most restrictive aspect. Typically it is a halt aspect, but e.g. for distant-only
signals this would be "expect stop".

A special case occurs for pure distant signals: Such signals must set apply_aspect, but must not set main_aspects. Behavior is as follows:
- Signal is uninitialized, distant signal is not assigned to a main signal, or no route is set: main_aspect == { name = "_halt", halt = true } and rem_aspect == nil
- A remote main signal is assigned (either by user or by route): main_aspect is always { name = "_default" } and rem_aspect / rem_aspinfo give the correct information

Main aspect names starting with underscore (e.g. "_default") are reserved and must not be used!
n class="hl str">"textarea[0.8,4.2;7,2;ars;Trains stopping here (ARS rules);"..advtrains.interlocking.ars_to_text(stdata.ars).."]"
	form = form.."button[0.5,6;7,1;save;"..attrans("Save").."]"
	
	minetest.show_formspec(pname, "at_lines_stop_"..pe, form)
end
local tmp_checkboxes = {}
minetest.register_on_player_receive_fields(function(player, formname, fields)
	local pname = player:get_player_name()
	local pe = string.match(formname, "^at_lines_stop_(............)$")
	local pos = advtrains.decode_pos(pe)
	if pos then
		if minetest.is_protected(pos, pname) then
			minetest.chat_send_player(pname, attrans("You are not allowed to configure this track."))
			return
		end
		
		local stdata = advtrains.lines.stops[pe]
		if not tmp_checkboxes[pe] then
			tmp_checkboxes[pe] = {}
		end
		if fields.kick then			-- handle checkboxes due to MT's weird handling
			tmp_checkboxes[pe].kick = (fields.kick == "true")
		end
		if fields.reverse then
			tmp_checkboxes[pe].reverse = (fields.reverse == "true")
		end
		if fields.save then
			if fields.stn and stdata.stn ~= fields.stn and fields.stn ~= "" then
				local stn = advtrains.lines.stations[fields.stn]
				if stn then
					if (stn.owner == pname or minetest.check_player_privs(pname, "train_admin")) then
						stdata.stn = fields.stn
					else
						minetest.chat_send_player(pname, attrans("Station code \"@1\" already exists and is owned by @2.", fields.stn, stn.owner))
						show_stoprailform(pos,player)
						return
					end
				else
					advtrains.lines.stations[fields.stn] = {name = fields.stnname, owner = pname}
					stdata.stn = fields.stn
				end
			end
			local stn = advtrains.lines.stations[stdata.stn]
			if stn and fields.stnname and fields.stnname~="" and fields.stnname ~= stn.name then
				if (stn.owner == pname or minetest.check_player_privs(pname, "train_admin")) then
					stn.name = fields.stnname
				else
					minetest.chat_send_player(pname, attrans("This station is owned by @1. You are not allowed to edit its name.", stn.owner))
				end
			end
			
			-- dropdowns
			if fields.doors then
				stdata.doors = door_dropdown_rev[fields.doors] or "C"
			end
			
			if fields.track then
				stdata.track = fields.track
			end
			if fields.wait then
				stdata.wait = to_int(fields.wait) or 10
			end
			
			if fields.ars then
				stdata.ars = advtrains.interlocking.text_to_ars(fields.ars)
			end

			if fields.ddelay then
				stdata.ddelay = to_int(fields.ddelay) or 1
			end
			if fields.speed then
				stdata.speed = to_int(fields.speed) or "M"
			end

			for k,v in pairs(tmp_checkboxes[pe]) do --handle checkboxes
				stdata[k] = v or nil
			end
			tmp_checkboxes[pe] = nil
			--TODO: signal
			updatemeta(pos)
			show_stoprailform(pos, player)
		end
	end			
	
end)


local adefunc = function(def, preset, suffix, rotation)
		return {
			after_place_node=function(pos)
				local pe = advtrains.encode_pos(pos)
				advtrains.lines.stops[pe] = {
					stn="", track="", doors="R", wait=10
				}
				updatemeta(pos)
			end,
			after_dig_node=function(pos)
				local pe = advtrains.encode_pos(pos)
				advtrains.lines.stops[pe] = nil
			end,
			on_rightclick = function(pos, node, player)
				show_stoprailform(pos, player)
			end,
			advtrains = {
				on_train_approach = function(pos,train_id, train, index, has_entered)
					if has_entered then return end -- do not stop again!
					if train.path_cn[index] == 1 then
						local pe = advtrains.encode_pos(pos)
						local stdata = advtrains.lines.stops[pe]
						if stdata and stdata.stn then
						
							--TODO REMOVE AFTER SOME TIME (only migration)
							if not stdata.ars then
								stdata.ars = {default=true}
							end
							if stdata.ars and (stdata.ars.default or advtrains.interlocking.ars_check_rule_match(stdata.ars, train) ) then
								advtrains.lzb_add_checkpoint(train, index, 2, nil)
								local stn = advtrains.lines.stations[stdata.stn]
								local stnname = stn and stn.name or "Unknown Station"
								train.text_inside = "Next Stop:\n"..stnname
								advtrains.interlocking.ars_set_disable(train, true)
							end
						end
					end
				end,
				on_train_enter = function(pos, train_id, train, index)
					if train.path_cn[index] == 1 then
						local pe = advtrains.encode_pos(pos)
						local stdata = advtrains.lines.stops[pe]
						if not stdata then
							return
						end
						
						if stdata.ars and (stdata.ars.default or advtrains.interlocking.ars_check_rule_match(stdata.ars, train) ) then
							local stn = advtrains.lines.stations[stdata.stn]
							local stnname = stn and stn.name or "Unknown Station"
							
							-- Send ATC command and set text
							advtrains.atc.train_set_command(train, "B0 W O"..stdata.doors..(stdata.kick and "K" or "").." D"..stdata.wait.." "..(stdata.reverse and "R" or "").." A1 G OC D"..(stdata.ddelay or 1) .. " S" ..(stdata.speed or "M"), true)
							train.text_inside = stnname
							if tonumber(stdata.wait) then
								minetest.after(tonumber(stdata.wait), function() train.text_inside = "" end)
							end
						end
					end
				end
			},
		}
end

if minetest.get_modpath("advtrains_train_track") ~= nil then
	advtrains.register_tracks("default", {
		nodename_prefix="advtrains_line_automation:dtrack_stop",
		texture_prefix="advtrains_dtrack_stop",
		models_prefix="advtrains_dtrack",
		models_suffix=".b3d",
		shared_texture="advtrains_dtrack_shared_stop.png",
		description=attrans("Station/Stop Track"),
		formats={},
		get_additional_definiton = adefunc,
	}, advtrains.trackpresets.t_30deg_straightonly)
end