lua: refactor destination helper

profiles/debug.lua

@@ -43,7 +43,7 @@ mode = {
 
 -- input tags, normally extracted from OSM data
 local way = {
-  highway = 'primary',
+  highway = 'motorway',
   name = 'Main Street',
   --width = '3',
   --maxspeed = '30',
@@ -57,6 +57,9 @@ local way = {
   --duration = '00:01:00',
   --hov = 'designated',
   --access = 'no'
+  --destination = 'Berlin',
+  ["destination:ref"] = 'Nuremberg',
+  --["destination:ref:forward"] = 'Hamburg;Dresden',
 }
 -- tag function normally provided via C++
 function way:get_value_by_key(k)

profiles/lib/destination.lua

@@ -1,53 +1,32 @@
 local Destination = {}
 
+function Destination.get_directional_tag(way, is_forward, tag)
+  local v
+  if is_forward then
+    v = way:get_value_by_key(tag .. ':forward') or way:get_value_by_key(tag)
+  else
+    v = way:get_value_by_key(tag .. ':backward') or way:get_value_by_key(tag)
+  end
+  if v then
+    return v.gsub(v, ';', ', ')
+  end
+end
+
+function Destination.join(a,b)
+  if a and b then
+    return a .. ': ' .. b
+  else
+    return a or b
+  end
+end
+
+-- Assemble destination as: "A59: Düsseldorf, Köln"
+--          destination:ref  ^    ^  destination
+
 function Destination.get_destination(way, is_forward)
-  local destination = way:get_value_by_key("destination")
+  destination_ref = Destination.get_directional_tag(way, is_forward, 'destination:ref')
-  local destination_forward = way:get_value_by_key("destination:forward")
+  destination     = Destination.get_directional_tag(way, is_forward, 'destination')
-  local destination_backward = way:get_value_by_key("destination:backward")
+  return Destination.join(destination_ref, destination) or ''
-  local destination_ref = way:get_value_by_key("destination:ref")
-  local destination_ref_forward = way:get_value_by_key("destination:ref:forward")
-  local destination_ref_backward = way:get_value_by_key("destination:ref:backward")
-
-  -- Assemble destination as: "A59: Düsseldorf, Köln"
-  --          destination:ref  ^    ^  destination
-  
-  local rv = ""
-
-  if destination_ref then
-    if is_forward == true and destination_ref == "" then
-      if destination_ref_forward then
-        destination_ref = destination_ref_forward
-      end
-    elseif is_forward == false then
-      if destination_ref_backward then
-        destination_ref = destination_ref_backward
-      end
-    end
-
-    rv = rv .. string.gsub(destination_ref, ";", ", ")
-  end
-
-  if destination then 
-    if is_forward == true and destination == "" then
-      if destination_forward then
-        destination = destination_forward
-      end
-    elseif is_forward == false then
-      if destination_backward then
-        destination = destination_backward
-      end
-    end
-
-    if destination ~= "" then
-      if rv ~= "" then
-          rv = rv .. ": "
-      end
-
-      rv = rv .. string.gsub(destination, ";", ", ")
-    end
-  end
-
-  return rv
 end
 
 return Destination

profiles/lib/guidance.lua

@@ -61,7 +61,7 @@ function Guidance.set_classification (highway, result, input_way)
     end
 
     local lane_count = input_way:get_value_by_key("lanes")
-    if lane_count and lane_count ~= "" then
+    if lane_count then
         local lc = tonumber(lane_count)
         if lc ~= nil then
             result.road_classification.num_lanes = lc
@@ -69,14 +69,14 @@ function Guidance.set_classification (highway, result, input_way)
     else
         local total_count = 0
         local forward_count = input_way:get_value_by_key("lanes:forward")
-        if forward_count and forward_count ~= "" then
+        if forward_count then
             local fc = tonumber(forward_count)
             if fc ~= nil then
                 total_count = fc
             end
         end
         local backward_count = input_way:get_value_by_key("lanes:backward")
-        if backward_count and backward_count ~= "" then
+        if backward_count then
             local bc = tonumber(backward_count)
             if bc ~= nil then
                 total_count = total_count + bc
@@ -96,19 +96,19 @@ local function get_psv_counts(way)
 
     local fw = 0;
     local bw = 0;
-    if  psv and psv ~= ""  then
+    if  psv then
         fw = tonumber(psv)
         if( fw == nil ) then
             fw = 0
         end
     end
-    if psv_forward and psv_forward ~= "" then
+    if psv_forward then
         fw = tonumber(psv_forward)
         if( fw == nil ) then
             fw = 0
         end
     end
-    if psv_backward and psv_backward ~= "" then
+    if psv_backward then
         bw = tonumber(psv_backward);
         if( bw == nil ) then
             bw = 0
@@ -119,8 +119,8 @@ end
 
 -- trims lane string with regard to supported lanes
 local function process_lanes(turn_lane,vehicle_lane,first_count,second_count)
-    if turn_lane and turn_lane ~= "" then
+    if turn_lane then
-        if vehicle_lane and vehicle_lane ~= "" then
+        if vehicle_lane then
             turn_lane = applyAccessTokens(turn_lane,vehicle_lane)
         elseif first_count ~= 0 or second_count ~= 0 then
             turn_lane = trimLaneString(turn_lane, first_count, second_count)