gluon osm openstreetmap lookups

osm.js

(function() {
  // descriptor
  return {name:"osm"}
})

// osm json
//{"bearing":345.9410965462545,"distance":355.0966239302687,
// "node":{"id":1963188104,"lat":45.5233261,"lon":-122.6584695,"tags":{...

function go(msg) {
  if (msg.method == "irc.privmsg") {
    var cmd = /^!osm(\s+(.*))?/.exec(msg.params.message)
    if(cmd) {
      if(cmd[2]) {
        bot.say(bot.admin_channel, "osm: "+msg.params.nick+' '+cmd[2])
        track(msg.params.nick, function(track){
          if (track) {
            //bot.say(msg.params.channel, msg.params.nick+' '+JSON.stringify(track.location))
            var data = osmtag(cmd[2], track.location.latitude, track.location.longitude, 0.01)
            bot.say(msg.params.channel, 'search +/-0.01 deg lat/lng of ['+
                    track.location.latitude.toFixed(4)+','+track.location.longitude.toFixed(4)+'] nodes found: '
                    +data.elements.length)
            if(data.elements.length == 0) { // try again, a bit wider
              data = osmtag(cmd[2], track.location.latitude, track.location.longitude, 0.1)
              bot.say(msg.params.channel, 'search +/-0.1 deg lat/lng of ['+
                      track.location.latitude.toFixed(4)+','+track.location.longitude.toFixed(4)+'] nodes found: '
                      +data.elements.length)
            }
            if(data.elements.length > 0) {
              var winner = closest(track.location, data.elements)
              var name = winner.node.tags['name'] ? winner.node.tags['name'] : "[no name]"
              var direction = headingDirection(winner.bearing) + "(" + winner.bearing.toFixed(0) + "°)" 
              var info = name+" is "+winner.distance.toFixed(0)+"m "+direction+" "+
                        " https://www.openstreetmap.org/node/"+winner.node.id
              bot.say(msg.params.channel, msg.params.nick+': '+info)
              var route = 'https://maps.openrouteservice.org/directions?c=0&a='
              route = route + [track.location.latitude, track.location.longitude, winner.node.lat, winner.node.lon].join(',')
              //bot.say(msg.params.channel, msg.params.nick+': route '+route)
            } else {
              bot.say(msg.params.channel, msg.params.nick+' no '+cmd[2]+' in your vicinity.')
            }
          } else {
            bot.say(msg.params.channel, 'no icecondor track for '+msg.params.nick)
          }
        })
      } else {
        bot.say(msg.params.channel, "!osm <tag_name>=<tag_value>")
      }
    }

    var barcmd = /^!nearestbar/.exec(msg.params.message)
    if(barcmd) {
      bot.say(bot.admin_channel, "osm: "+msg.params.nick+' !nearestbar')
      track(msg.params.nick, function(track){
        if (track) {
          var barfind = 'amenity~"^bar$|^pub$"'
          var data = osmtag(barfind, track.location.latitude, track.location.longitude, 0.02)
          if(data.elements.length > 0) {
            var winner = closest(track.location, data.elements)
            var name = winner.node.tags['name'] ? winner.node.tags['name'] : ""
            var direction = winner.distance.toFixed(0) + ' meters ' + headingDirection(winner.bearing)
            bot.say(msg.params.channel, msg.params.nick+': '+name+'. '+direction)
          } else {
            bot.say(msg.params.channel, msg.params.nick+": nothing within 0.02deg of you.")
          }
        }
      })
    }
    
    var nearest = /^!nearest(\s+(.*))/.exec(msg.params.message)
    if(nearest) {
      track(msg.params.nick, function(track){
        if (track) {
          var query = 'amenity~"'+nearest[2]+'"'
          bot.say(msg.params.channel, msg.params.nick+": "+query)
          var data = osmtag(query, track.location.latitude, track.location.longitude, 0.02)
          if(data.elements.length > 0) {
            var winner = closest(track.location, data.elements)
            var name = winner.node.tags['name'] ? winner.node.tags['name'] : ""
            var direction = winner.distance.toFixed(0) + ' meters ' + headingDirection(winner.bearing)
            var node_url = "https://www.openstreetmap.org/node/"+winner.node.id
            bot.say(msg.params.channel, msg.params.nick+': '+name+'. '+direction+' '+node_url)
          } else {
            bot.say(msg.params.channel, msg.params.nick+": nothing within 0.02deg of you.")
          }
        }
      })
    }    
  }
}

function closest(me, nodes) {
  var winner = {node: null, distance: null}
  nodes.forEach(function(node){
    var meDistance = pointDistance(me, {latitude: node.lat, longitude: node.lon})
    if(!winner.node || meDistance < winner.distance) {
      winner.node = node
      winner.distance = meDistance
      winner.bearing = segmentBearing(me, {latitude: node.lat, longitude: node.lon})
    }
  })
  return winner
}

function osmtag(tag, lat, lng, delta) {
  var url = 'http://overpass-api.de/api/interpreter'
  var coords = [lat-delta, lng-delta, lat+delta, lng+delta]
  var tagquery
  if(tag.indexOf('=') > 0 || tag.indexOf('~') > 0) {
    tagquery = tag
  } else {
    tagquery = "\"name\"~\""+tag+"\",i"
  }
  var overpass = '[out:json];' +
                 //'node('+coords.join(',')+')['+tagquery+'];'+
                 '(node('+coords.join(',')+')['+tagquery+'];'+
                 'way('+coords.join(',')+')['+tagquery+'];);'+
                 '(._;>;);'+
                 'out;'
  //(node(45.5016018,-122.6960055,45.6216018,-122.57600549999999) [aeroway=aerodrome];
  // way(45.5016018,-122.6960055,46.5216018,-122.57600549999999) [aeroway=aerodrome];);
  //(._;>;);
  bot.say(bot.admin_channel, overpass)
  var resp =  http.get({url:url+'?data='+encodeURIComponent(overpass)})
  bot.say(bot.admin_channel, url+'?data='+encodeURIComponent(overpass))
  if(resp.status != 200) {
    bot.say(bot.admin_channel, "osm http "+resp.status)
  }
  
  var data = JSON.parse(resp.body)
  var filtered = data.elements.filter(function(n){return n.tags})
  bot.say(bot.admin_channel, "osm found "+data.elements.length+" nodes and "+filtered.length+" nodes with tags")
  data.elements = filtered
  return data
}

function track(username, cb) {
  db.get('icecondor:user'+':'+username+':track', function(trackJson){
    var track
    if (trackJson) { 
      cb(JSON.parse(trackJson))
    } else { cb() }
  })
}

// from http://www.movable-type.co.uk/scripts/latlong.html
function pointDistance(la, lb) {
  var lat1 = la.latitude, lon1 = la.longitude
  var lat2 = lb.latitude, lon2 = lb.longitude
  
  var dLat = numberToRadius(lat2 - lat1),
      dLon = numberToRadius(lon2 - lon1),
      a = Math.pow(Math.sin(dLat / 2), 2) + Math.cos(numberToRadius(lat1))
        * Math.cos(numberToRadius(lat2)) * Math.pow(Math.sin(dLon / 2), 2),
      c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    return (6371 * c) * 1000; // returns meters
}

function numberToRadius(number) {
    return number * Math.PI / 180;
}

function numberToDegree(number) {
    return number * 180 / Math.PI
}

function segmentBearing(loc1, loc2) {
  var λ1 = numberToRadius(loc1.longitude)
  var λ2 = numberToRadius(loc2.longitude)
  var φ1 = numberToRadius(loc1.latitude)
  var φ2 = numberToRadius(loc2.latitude)  
  var y = Math.sin(λ2-λ1) * Math.cos(φ2);
  var x = Math.cos(φ1)*Math.sin(φ2) -
        Math.sin(φ1)*Math.cos(φ2)*Math.cos(λ2-λ1);
  var brng = Math.atan2(y, x)// .toDegrees()
  var bearingDegrees = numberToDegree(brng)
  var offset = (bearingDegrees < 0) ? 360 : 0
  return offset + bearingDegrees
}

function headingDirection(degrees) {
  var directions = ["north", "northeast", "east", "southeast", "south", "southwest", "west", "northwest"]
  var anglewidth = 360 / directions.length
  var halfwidth = anglewidth/2
  for(var i=0; i < directions.length; i++) {
    var j = i == 0 ? directions.length-1 : i-1
    var min = (anglewidth*j)+halfwidth
    var max = (anglewidth*i)+halfwidth    
    var inside
    if(i==0) {
      inside = degrees <= max || degrees > min
    } else {
      inside = degrees <= max && degrees > min
    }
    if(inside) return directions[i]
  }
}