Module:GeoSetsNav

 local p = {}

 function p.renderMap(frame)
 -- Try to get parameters from the current frame; if empty, check the parent frame.
 local args = frame.args
 if not next(args) then
 args = frame:getParent().args
 end

 local markers = {}
 for k, v in pairs(args) do
 if k:match("^marker%d+$") then
 -- Expect each value in the format: lat,lon,label
 local lat, lon, label = v:match("^%s*([%-%.%d]+)%s*,%s*([%-%.%d]+)%s*,%s*(.+)%s*$")
 if lat and lon and label then
 table.insert(markers, { lat = lat, lon = lon, label = label })
 end
 end
 end

 if #markers == 0 then
 return "No markers provided."
 end

 -- Build parameters for Template:Maplink.
 local params = {}
 params.frame = "yes" -- display the map in a frame
 params.plain = "no" -- include the surrounding frame (set to "yes" for no frame)
 params.zoom = args.zoom or "18" -- default zoom level; adjust as needed
 params["frame-width"] = args["frame-width"] or "800" -- default width if not set
 params["frame-height"] = args["frame-height"] or "600" -- default height if not set

 -- Function to convert a coordinate value (as string) into the expected format
 local function formatCoord(value, isLat)
 local num = tonumber(value)
 if not num then return nil end
 local absVal = tostring(math.abs(num))
 local hemisphere = ""
 if isLat then
 hemisphere = num < 0 and "S" or "N"
 else
 hemisphere = num < 0 and "W" or "E"
 end
 return absVal .. "_" .. hemisphere
 end

 for i, marker in ipairs(markers) do
 local latStr = formatCoord(marker.lat, true)
 local lonStr = formatCoord(marker.lon, false)
 if not (latStr and lonStr) then
 -- Skip markers with invalid numeric coordinates.
 else
 local coordStr = latStr .. "_" .. lonStr -- e.g. "19.928323_N_43.938624_W"
 if i == 1 then
 params.type = "point"
 params.coord = coordStr
 params.title = marker.label
 else
 params["type" .. i] = "point"
 params["coord" .. i] = coordStr
 params["title" .. i] = marker.label
 end
 end
 end

 return frame:expandTemplate{
 title = "Maplink",
 args = params
 }
 end

 return p