mapcomplete/Logic/ExtraFunctions.ts

429 lines
18 KiB
TypeScript

import {GeoOperations} from "./GeoOperations";
import Combine from "../UI/Base/Combine";
import RelationsTracker from "./Osm/RelationsTracker";
import BaseUIElement from "../UI/BaseUIElement";
import List from "../UI/Base/List";
import Title from "../UI/Base/Title";
import {BBox} from "./BBox";
export interface ExtraFuncParams {
/**
* Gets all the features from the given layer within the given BBOX.
* Note that more features then requested can be given back.
* Format: [ [ geojson, geojson, geojson, ... ], [geojson, ...], ...]
*/
getFeaturesWithin: (layerId: string, bbox: BBox) => any[][],
memberships: RelationsTracker
getFeatureById: (id: string) => any
}
/**
* Describes a function that is added to a geojson object in order to calculate calculated tags
*/
interface ExtraFunction {
readonly _name: string;
readonly _args: string[];
readonly _doc: string;
readonly _f: (params: ExtraFuncParams, feat: any) => any;
}
class OverlapFunc implements ExtraFunction {
_name = "overlapWith";
_doc = "Gives a list of features from the specified layer which this feature (partly) overlaps with. A point which is embedded in the feature is detected as well." +
"If the current feature is a point, all features that this point is embeded in are given.\n\n" +
"The returned value is `{ feat: GeoJSONFeature, overlap: number}[]` where `overlap` is the overlapping surface are (in m²) for areas, the overlapping length (in meter) if the current feature is a line or `undefined` if the current feature is a point.\n" +
"The resulting list is sorted in descending order by overlap. The feature with the most overlap will thus be the first in the list\n" +
"\n" +
"For example to get all objects which overlap or embed from a layer, use `_contained_climbing_routes_properties=feat.overlapWith('climbing_route')`"
_args = ["...layerIds - one or more layer ids of the layer from which every feature is checked for overlap)"]
_f(params, feat) {
return (...layerIds: string[]) => {
const result: { feat: any, overlap: number }[] = []
const bbox = BBox.get(feat)
for (const layerId of layerIds) {
const otherLayers = params.getFeaturesWithin(layerId, bbox)
if (otherLayers === undefined) {
continue;
}
if (otherLayers.length === 0) {
continue;
}
for (const otherLayer of otherLayers) {
result.push(...GeoOperations.calculateOverlap(feat, otherLayer));
}
}
result.sort((a, b) => b.overlap - a.overlap)
return result;
}
}
}
class IntersectionFunc implements ExtraFunction {
_name = "intersectionsWith";
_doc = "Gives the intersection points with selected features. Only works with (Multi)Polygons and LineStrings.\n\n" +
"Returns a `{feat: GeoJson, intersections: [number,number][]}` where `feat` is the full, original feature. This list is in random order.\n\n" +
"If the current feature is a point, this function will return an empty list.\n" +
"Points from other layers are ignored - even if the points are parts of the current linestring."
_args = ["...layerIds - one or more layer ids of the layer from which every feature is checked for intersection)"]
_f(params: ExtraFuncParams, feat) {
return (...layerIds: string[]) => {
const result: { feat: any, intersections: [number, number][] }[] = []
const bbox = BBox.get(feat)
for (const layerId of layerIds) {
const otherLayers = params.getFeaturesWithin(layerId, bbox)
if (otherLayers === undefined) {
continue;
}
if (otherLayers.length === 0) {
continue;
}
for (const tile of otherLayers) {
for (const otherFeature of tile) {
const intersections = GeoOperations.LineIntersections(feat, otherFeature)
if (intersections.length === 0) {
continue
}
result.push({feat: otherFeature, intersections})
}
}
}
return result;
}
}
}
class DistanceToFunc implements ExtraFunction {
_name = "distanceTo";
_doc = "Calculates the distance between the feature and a specified point in meter. The input should either be a pair of coordinates, a geojson feature or the ID of an object";
_args = ["feature OR featureID OR longitude", "undefined OR latitude"]
_f(featuresPerLayer, feature) {
return (arg0, lat) => {
if (arg0 === undefined) {
return undefined;
}
if (typeof arg0 === "number") {
// Feature._lon and ._lat is conveniently place by one of the other metatags
return GeoOperations.distanceBetween([arg0, lat], GeoOperations.centerpointCoordinates(feature));
}
if (typeof arg0 === "string") {
// This is an identifier
const feature = featuresPerLayer.getFeatureById(arg0)
if (feature === undefined) {
return undefined;
}
arg0 = feature;
}
// arg0 is probably a geojsonfeature
return GeoOperations.distanceBetween(GeoOperations.centerpointCoordinates(arg0), GeoOperations.centerpointCoordinates(feature))
}
}
}
class ClosestObjectFunc implements ExtraFunction {
_name = "closest"
_doc = "Given either a list of geojson features or a single layer name, gives the single object which is nearest to the feature. In the case of ways/polygons, only the centerpoint is considered. Returns a single geojson feature or undefined if nothing is found (or not yet laoded)"
_args = ["list of features or a layer name or '*' to get all features"]
_f(params, feature) {
return (features) => ClosestNObjectFunc.GetClosestNFeatures(params, feature, features)?.[0]?.feat
}
}
class ClosestNObjectFunc implements ExtraFunction {
_name = "closestn"
_doc = "Given either a list of geojson features or a single layer name, gives the n closest objects which are nearest to the feature (excluding the feature itself). In the case of ways/polygons, only the centerpoint is considered. " +
"Returns a list of `{feat: geojson, distance:number}` the empty list if nothing is found (or not yet loaded)\n\n" +
"If a 'unique tag key' is given, the tag with this key will only appear once (e.g. if 'name' is given, all features will have a different name)"
_args = ["list of features or layer name or '*' to get all features", "amount of features", "unique tag key (optional)", "maxDistanceInMeters (optional)"]
/**
* Gets the closes N features, sorted by ascending distance.
*
* @param params: The link to mapcomplete state
* @param feature: The central feature under consideration
* @param features: The other features
* @param options: maxFeatures: The maximum amount of features to be returned. Default: 1; uniqueTag: returned features are not allowed to have the same value for this key; maxDistance: stop searching if it is too far away (in meter). Default: 500m
* @constructor
* @private
*/
static GetClosestNFeatures(params: ExtraFuncParams,
feature: any,
features: string | any[],
options?: { maxFeatures?: number, uniqueTag?: string | undefined, maxDistance?: number }): { feat: any, distance: number }[] {
const maxFeatures = options?.maxFeatures ?? 1
const maxDistance = options?.maxDistance ?? 500
const uniqueTag: string | undefined = options?.uniqueTag
if (typeof features === "string") {
const name = features
const bbox = GeoOperations.bbox(GeoOperations.buffer(GeoOperations.bbox(feature), maxDistance))
features = params.getFeaturesWithin(name, new BBox(bbox.geometry.coordinates))
} else {
features = [features]
}
if (features === undefined) {
return;
}
const selfCenter = GeoOperations.centerpointCoordinates(feature)
let closestFeatures: { feat: any, distance: number }[] = [];
for (const featureList of features) {
// Features is provided by 'getFeaturesWithin' which returns a list of lists of features, hence the double loop here
for (const otherFeature of featureList) {
if (otherFeature === feature || otherFeature.properties.id === feature.properties.id) {
continue; // We ignore self
}
const distance = GeoOperations.distanceBetween(
GeoOperations.centerpointCoordinates(otherFeature),
selfCenter
)
if (distance === undefined || distance === null || isNaN(distance)) {
console.error("Could not calculate the distance between", feature, "and", otherFeature)
throw "Undefined distance!"
}
if (distance === 0) {
console.trace("Got a suspiciously zero distance between", otherFeature, "and self-feature", feature)
}
if (distance > maxDistance) {
continue
}
if (closestFeatures.length === 0) {
// This is the first matching feature we find - always add it
closestFeatures.push({
feat: otherFeature,
distance: distance
})
continue;
}
if (closestFeatures.length >= maxFeatures && closestFeatures[maxFeatures - 1].distance < distance) {
// The last feature of the list (and thus the furthest away is still closer
// No use for checking, as we already have plenty of features!
continue
}
let targetIndex = closestFeatures.length
for (let i = 0; i < closestFeatures.length; i++) {
const closestFeature = closestFeatures[i];
if (uniqueTag !== undefined) {
const uniqueTagsMatch = otherFeature.properties[uniqueTag] !== undefined &&
closestFeature.feat.properties[uniqueTag] === otherFeature.properties[uniqueTag]
if (uniqueTagsMatch) {
targetIndex = -1
if (closestFeature.distance > distance) {
// This is a very special situation:
// We want to see the tag `uniquetag=some_value` only once in the entire list (e.g. to prevent road segements of identical names to fill up the list of 'names of nearby roads')
// AT this point, we have found a closer segment with the same, identical tag
// so we replace directly
closestFeatures[i] = {feat: otherFeature, distance: distance}
}
break;
}
}
if (closestFeature.distance > distance) {
targetIndex = i
if (uniqueTag !== undefined) {
const uniqueValue = otherFeature.properties[uniqueTag]
// We might still have some other values later one with the same uniquetag that have to be cleaned
for (let j = i; j < closestFeatures.length; j++) {
if (closestFeatures[j].feat.properties[uniqueTag] === uniqueValue) {
closestFeatures.splice(j, 1)
}
}
}
break;
}
}
if (targetIndex == -1) {
continue; // value is already swapped by the unique tag
}
if (targetIndex < maxFeatures) {
// insert and drop one
closestFeatures.splice(targetIndex, 0, {
feat: otherFeature,
distance: distance
})
if (closestFeatures.length >= maxFeatures) {
closestFeatures.splice(maxFeatures, 1)
}
} else {
// Overwrite the last element
closestFeatures[targetIndex] = {
feat: otherFeature,
distance: distance
}
}
}
}
return closestFeatures;
}
_f(params, feature) {
return (features, amount, uniqueTag, maxDistanceInMeters) => {
let distance: number = Number(maxDistanceInMeters)
if (isNaN(distance)) {
distance = undefined
}
return ClosestNObjectFunc.GetClosestNFeatures(params, feature, features, {
maxFeatures: Number(amount),
uniqueTag: uniqueTag,
maxDistance: distance
});
}
}
}
class Memberships implements ExtraFunction {
_name = "memberships"
_doc = "Gives a list of `{role: string, relation: Relation}`-objects, containing all the relations that this feature is part of. " +
"\n\n" +
"For example: `_part_of_walking_routes=feat.memberships().map(r => r.relation.tags.name).join(';')`"
_args = []
_f(params, feat) {
return () =>
params.memberships.knownRelations.data.get(feat.properties.id) ?? []
}
}
class GetParsed implements ExtraFunction {
_name = "get"
_doc = "Gets the property of the feature, parses it (as JSON) and returns it. Might return 'undefined' if not defined, null, ..."
_args = ["key"]
_f(params, feat) {
return key => {
const value = feat.properties[key]
if (value === undefined) {
return undefined;
}
try {
const parsed = JSON.parse(value)
if (parsed === null) {
return undefined;
}
return parsed;
} catch (e) {
console.warn("Could not parse property " + key + " due to: " + e + ", the value is " + value)
return undefined;
}
}
}
}
export class ExtraFunctions {
static readonly intro = new Combine([
new Title("Calculating tags with Javascript", 2),
"In some cases, it is useful to have some tags calculated based on other properties. Some useful tags are available by default (e.g. `lat`, `lon`, `_country`), as detailed above.",
"It is also possible to calculate your own tags - but this requires some javascript knowledge.",
"",
"Before proceeding, some warnings:",
new List([
"DO NOT DO THIS AS BEGINNER",
"**Only do this if all other techniques fail** This should _not_ be done to create a rendering effect, only to calculate a specific value",
"**THIS MIGHT BE DISABLED WITHOUT ANY NOTICE ON UNOFFICIAL THEMES** As unofficial themes might be loaded from the internet, this is the equivalent of injecting arbitrary code into the client. It'll be disabled if abuse occurs."
]),
"To enable this feature, add a field `calculatedTags` in the layer object, e.g.:",
"````",
"\"calculatedTags\": [",
" \"_someKey=javascript-expression\",",
" \"name=feat.properties.name ?? feat.properties.ref ?? feat.properties.operator\",",
" \"_distanceCloserThen3Km=feat.distanceTo( some_lon, some_lat) < 3 ? 'yes' : 'no'\" ",
" ]",
"````",
"",
"The above code will be executed for every feature in the layer. The feature is accessible as `feat` and is an amended geojson object:",
new List([
"`area` contains the surface area (in square meters) of the object",
"`lat` and `lon` contain the latitude and longitude"
]),
"Some advanced functions are available on **feat** as well:"
]).SetClass("flex-col").AsMarkdown();
private static readonly allFuncs: ExtraFunction[] = [
new DistanceToFunc(),
new OverlapFunc(),
new IntersectionFunc(),
new ClosestObjectFunc(),
new ClosestNObjectFunc(),
new Memberships(),
new GetParsed()
];
public static FullPatchFeature(params: ExtraFuncParams, feature) {
if (feature._is_patched) {
return
}
feature._is_patched = true
for (const func of ExtraFunctions.allFuncs) {
feature[func._name] = func._f(params, feature)
}
}
public static HelpText(): BaseUIElement {
const elems = []
for (const func of ExtraFunctions.allFuncs) {
elems.push(new Title(func._name, 3),
func._doc,
new List(func._args ?? [], true))
}
return new Combine([
ExtraFunctions.intro,
new List(ExtraFunctions.allFuncs.map(func => `[${func._name}](#${func._name})`)),
...elems
]);
}
}