add parsePolyline to default profile

lib/default-profile.js

@@ -6,6 +6,7 @@ const parseJourneyLeg = require('../parse/journey-leg')
 const parseJourney = require('../parse/journey')
 const parseLine = require('../parse/line')
 const parseLocation = require('../parse/location')
+const parsePolyline = require('../parse/polyline')
 const parseMovement = require('../parse/movement')
 const parseNearby = require('../parse/nearby')
 const parseOperator = require('../parse/operator')
@@ -42,6 +43,7 @@ const defaultProfile = {
 	parseLine,
 	parseStationName: id,
 	parseLocation,
+	parsePolyline,
 	parseMovement,
 	parseNearby,
 	parseOperator,

package.json

@@ -32,8 +32,10 @@
 		"node": ">=6"
 	},
 	"dependencies": {
+		"@mapbox/polyline": "^1.0.0",
 		"capture-stack-trace": "^1.0.0",
 		"fetch-ponyfill": "^6.0.0",
+		"gps-distance": "0.0.4",
 		"lodash": "^4.17.5",
 		"luxon": "^0.5.8",
 		"p-throttle": "^1.1.0",

parse/polyline.js

@@ -0,0 +1,53 @@
+'use strict'
+
+const {toGeoJSON} = require('@mapbox/polyline')
+const distance = require('gps-distance')
+
+const createParsePolyline = (locations) => {
+	// todo: what is p.delta?
+	// todo: what is p.type?
+	// todo: what is p.crdEncS?
+	// todo: what is p.crdEncF?
+	const parsePolyline = (p) => {
+		const shape = toGeoJSON(p.crdEncYX)
+		if (shape.coordinates.length === 0) return null
+
+		const res = shape.coordinates.map(crd => ({
+			type: 'Feature',
+			properties: {},
+			geometry: {
+				type: 'Point',
+				coordinates: crd
+			}
+		}))
+
+		if (Array.isArray(p.ppLocRefL)) {
+			for (let ref of p.ppLocRefL) {
+				const p = res[ref.ppIdx]
+				const loc = locations[ref.locX]
+				if (p && loc) p.properties = loc
+			}
+
+			// Often there is one more point right next to each point at a station.
+			// We filter them here if they are < 5m from each other.
+			for (let i = 1; i < res.length; i++) {
+				const p1 = res[i - 1].geometry.coordinates
+				const p2 = res[i].geometry.coordinates
+				const d = distance(p1[1], p1[0], p2[1], p2[0])
+				if (d >= .005) continue
+				const l1 = Object.keys(res[i - 1].properties).length
+				const l2 = Object.keys(res[i].properties).length
+				if (l1 === 0 && l2 > 0) res.splice(i - 1, 1)
+				else if (l2 === 0 && l1 > 0) res.splice(i, 1)
+			}
+		}
+
+		return {
+			type: 'FeatureCollection',
+			features: res
+		}
+	}
+	return parsePolyline
+}
+
+module.exports = createParsePolyline