// FOSSGIS engine (OSRM based)
// Doesn't yet support hints

function FOSSGISEngine(id, vehicleType) {
  var cachedHints = [];

  return {
    id: id,
    creditline: "<a href=\"https://routing.openstreetmap.de/about.html\" target=\"_blank\">FOSSGIS Routing Service</a>",
    draggable: true,

    _transformSteps: function (input_steps, line) {
      var INSTRUCTION_TEMPLATE = {
        "continue": "javascripts.directions.instructions.continue",
        "merge right": "javascripts.directions.instructions.merge_right",
        "merge left": "javascripts.directions.instructions.merge_left",
        "off ramp right": "javascripts.directions.instructions.offramp_right",
        "off ramp left": "javascripts.directions.instructions.offramp_left",
        "on ramp right": "javascripts.directions.instructions.onramp_right",
        "on ramp left": "javascripts.directions.instructions.onramp_left",
        "fork right": "javascripts.directions.instructions.fork_right",
        "fork left": "javascripts.directions.instructions.fork_left",
        "end of road right": "javascripts.directions.instructions.endofroad_right",
        "end of road left": "javascripts.directions.instructions.endofroad_left",
        "turn straight": "javascripts.directions.instructions.continue",
        "turn slight right": "javascripts.directions.instructions.slight_right",
        "turn right": "javascripts.directions.instructions.turn_right",
        "turn sharp right": "javascripts.directions.instructions.sharp_right",
        "turn uturn": "javascripts.directions.instructions.uturn",
        "turn sharp left": "javascripts.directions.instructions.sharp_left",
        "turn left": "javascripts.directions.instructions.turn_left",
        "turn slight left": "javascripts.directions.instructions.slight_left",
        "roundabout": "javascripts.directions.instructions.roundabout",
        "rotary": "javascripts.directions.instructions.roundabout",
        "exit roundabout": "javascripts.directions.instructions.exit_roundabout",
        "exit rotary": "javascripts.directions.instructions.exit_roundabout",
        "depart": "javascripts.directions.instructions.start",
        "arrive": "javascripts.directions.instructions.destination"
      };
      var ICON_MAP = {
        "continue": 0,
        "merge right": 21,
        "merge left": 20,
        "off ramp right": 24,
        "off ramp left": 25,
        "on ramp right": 2,
        "on ramp left": 6,
        "fork right": 18,
        "fork left": 19,
        "end of road right": 22,
        "end of road left": 23,
        "turn straight": 0,
        "turn slight right": 1,
        "turn right": 2,
        "turn sharp right": 3,
        "turn uturn": 4,
        "turn slight left": 5,
        "turn left": 6,
        "turn sharp left": 7,
        "roundabout": 10,
        "rotary": 10,
        "exit roundabout": 10,
        "exit rotary": 10,
        "depart": 8,
        "arrive": 14
      };
      var numToWord = function (num) {
        return ["first", "second", "third", "fourth", "fifth", "sixth", "seventh", "eighth", "ninth", "tenth"][num - 1];
      };
      var transformed_steps = input_steps.map(function (step, idx) {
        var maneuver_id;

        // special case handling
        switch (step.maneuver.type) {
          case "on ramp":
          case "off ramp":
          case "merge":
          case "end of road":
          case "fork":
            maneuver_id = step.maneuver.type + " " + (step.maneuver.modifier.indexOf("left") >= 0 ? "left" : "right");
            break;
          case "depart":
          case "arrive":
          case "roundabout":
          case "rotary":
          case "exit roundabout":
          case "exit rotary":
            maneuver_id = step.maneuver.type;
            break;
          case "roundabout turn":
          case "turn":
            maneuver_id = "turn " + step.maneuver.modifier;
            break;
          // for unknown types the fallback is turn
          default:
            maneuver_id = "turn " + step.maneuver.modifier;
            break;
        }
        var template = INSTRUCTION_TEMPLATE[maneuver_id];

        // convert lat,lng pairs to LatLng objects
        var step_geometry = L.PolylineUtil.decode(step.geometry, { precision: 5 }).map(function (a) { return L.latLng(a); });
        // append step_geometry on line
        Array.prototype.push.apply(line, step_geometry);

        var instText = "<b>" + (idx + 1) + ".</b> ";
        var destinations = "<b>" + step.destinations + "</b>";
        var namedRoad = true;
        var name;

        if (step.name && step.ref) {
          name = "<b>" + step.name + " (" + step.ref + ")</b>";
        } else if (step.name) {
          name = "<b>" + step.name + "</b>";
        } else if (step.ref) {
          name = "<b>" + step.ref + "</b>";
        } else {
          name = I18n.t("javascripts.directions.instructions.unnamed");
          namedRoad = false;
        }

        if (step.maneuver.type.match(/^exit (rotary|roundabout)$/)) {
          instText += I18n.t(template, { name: name });
        } else if (step.maneuver.type.match(/^(rotary|roundabout)$/)) {
          if (step.maneuver.exit) {
            if (step.maneuver.exit <= 10) {
              instText += I18n.t(template + "_with_exit_ordinal", { exit: I18n.t("javascripts.directions.instructions.exit_counts." + numToWord(step.maneuver.exit)), name: name });
            } else {
              instText += I18n.t(template + "_with_exit", { exit: step.maneuver.exit, name: name });
            }
          } else {
            instText += I18n.t(template + "_without_exit", { name: name });
          }
        } else if (step.maneuver.type.match(/^(on ramp|off ramp)$/)) {
          var params = {};
          if (step.exits && step.maneuver.type.match(/^(off ramp)$/)) params.exit = step.exits;
          if (step.destinations) params.directions = destinations;
          if (namedRoad) params.directions = name;
          if (Object.keys(params).length > 0) {
            template = template + "_with_" + Object.keys(params).join("_");
          }
          instText += I18n.t(template, params);
        } else {
          instText += I18n.t(template + "_without_exit", { name: name });
        }
        return [[step.maneuver.location[1], step.maneuver.location[0]], ICON_MAP[maneuver_id], instText, step.distance, step_geometry];
      });

      return transformed_steps;
    },

    getRoute: function (points, callback) {
      var params = [
        { name: "overview", value: "false" },
        { name: "geometries", value: "polyline" },
        { name: "steps", value: true }
      ];


      if (cachedHints.length === points.length) {
        params.push({ name: "hints", value: cachedHints.join(";") });
      } else {
        // invalidate cache
        cachedHints = [];
      }

      var encoded_coords = points.map(function (p) {
        return p.lng + "," + p.lat;
      }).join(";");

      var req_url = OSM.FOSSGIS_OSRM_URL + "routed-" + vehicleType + "/route/v1/driving/" + encoded_coords;

      var onResponse = function (data) {
        if (data.code !== "Ok") {
          return callback(true);
        }

        cachedHints = data.waypoints.map(function (wp) {
          return wp.hint;
        });

        var line = [];
        var transformLeg = function (leg) {
          return this._transformSteps(leg.steps, line);
        };

        var steps = [].concat.apply([], data.routes[0].legs.map(transformLeg.bind(this)));

        callback(false, {
          line: line,
          steps: steps,
          distance: data.routes[0].distance,
          time: data.routes[0].duration
        });
      };

      return $.ajax({
        url: req_url,
        data: params,
        dataType: "json",
        success: onResponse.bind(this),
        error: function () {
          callback(true);
        }
      });
    }
  };
}

OSM.Directions.addEngine(new FOSSGISEngine("fossgis_osrm_car", "car"), true);
OSM.Directions.addEngine(new FOSSGISEngine("fossgis_osrm_bike", "bike"), true);
OSM.Directions.addEngine(new FOSSGISEngine("fossgis_osrm_foot", "foot"), true);