-module(osrm).
-export([get_route/1, get_route/2, read_route/1]).
-import(polyline, [decode/1]).
%https://github.com/Project-OSRM/osrm-backend/wiki/Server-api
%For now, get weather for one location (probably good enough as relatively short distances weather wise; ultimately consider time as well?)
%To get lats and longs could also do a query for here: http://www.uk-postcodes.com/ (json again)
-define(BASE_URL,
"http://router.project-osrm.org/").
-define(VIAROUTE,
"viaroute").
%Need hints and checksum
%First one for command line usage
%%These will be strings from the command line
get_route([Start_lat, Start_lon, Finish_lat, Finish_lon]) ->
get_route([Start_lat, Start_lon], [Finish_lat, Finish_lon]).
get_route([Start_lat, Start_lon], [Finish_lat, Finish_lon]) ->
inets:start(),
URL = ?BASE_URL ++ ?VIAROUTE ++ "?loc=" ++ Start_lat ++ "," ++ Start_lon ++ "&loc=" ++ Finish_lat ++ "," ++ Finish_lon,
%Need UA to work with OSRM API
UA = "Mozilla/5.0 (X11; NetBSD i386; rv:28.0) Gecko/20100101 Firefox/28.0",
try
%Handling timeouts: http://stackoverflow.com/a/14143762/208793
{ ok, {_Status, _Headers, Body }} = httpc:request(get, {URL, [{"User-Agent", UA}]}, [{timeout, timer:seconds(10)}], []),
%For development purposes, write this out and keep it
_Write_status = file:write_file(os:getenv("HOME") ++ "/.headsilose_route", Body),
%Need to catch file write errors as well
Body
catch
_:Reason ->
io:format("API Might be down~n"),
Reason
after
maybe_quit()
end.
read_route(Route_choice) ->
{_Status, Route} = file:read_file(os:getenv("HOME") ++ "/.headsilose_route"),
%Use jiffy
%http://www.snip2code.com/Snippet/51463/how-to-support-chinese-in-http-request-b/
{ Props } = jiffy:decode(Route),
Route_geometry = if Route_choice =:= "route_geometry" ->
proplists:get_value(binary:list_to_bin(Route_choice), Props);
Route_choice =:= "alternative_geometries" ->
%hd only if alternative though!
%for now I think there is only ever one alternative so that is why we pick hd
hd(proplists:get_value(binary:list_to_bin(Route_choice), Props))
end,
%That is all for now? Because...
%And these don't seem to actually be returned, hence having to go down the route of polyline decoding
%Route_Instructions = proplists:get_value(<<"route_instructions">>, Props),
%Total_Distance = proplists:get_value(<<"total_distance">>, proplists:get_value(<<"route_summary">>, Props)),
%And need to figure out how to get nested values. I.e like xpath. Just nest the queries? Nope that doesn't work
%Like so:
{Hint_data} = proplists:get_value(<<"hint_data">>, Props),
Checksum = proplists:get_value(<<"checksum">>, Hint_data),
Route_geometry_as_string = binary:bin_to_list(Route_geometry),
{Checksum, Route_geometry_as_string}.
maybe_quit() ->
Args = init:get_arguments(),
Found = lists:keyfind(noshell, 1, Args),
if Found =:= false ->
dont_quit;
true ->
init:stop()
end.