import { Store, UIEventSource } from "../UIEventSource"
import GeocodingProvider, { SearchResult, GeocodingOptions } from "./GeocodingProvider"
import { OsmId } from "../../Models/OsmFeature"
import { SpecialVisualizationState } from "../../UI/SpecialVisualization"

export default class OpenStreetMapIdSearch implements GeocodingProvider {
    private static regex = /((https?:\/\/)?(www.)?(osm|openstreetmap).org\/)?(node|way|relation)\/([0-9]+)/

    private readonly _state: SpecialVisualizationState

    constructor(state: SpecialVisualizationState) {
        this._state = state
    }

    /**
     *
     * OpenStreetMapIdSearch.extractId("osm.org/node/42") // => "node/42"
     * OpenStreetMapIdSearch.extractId("https://openstreetmap.org/node/42#map=19/51.204245/3.212731") // => "node/42"
     * OpenStreetMapIdSearch.extractId("node/42") // => "node/42"
     * OpenStreetMapIdSearch.extractId("way/42") // => "way/42"
     * OpenStreetMapIdSearch.extractId("https://www.openstreetmap.org/node/5212733638") // => "node/5212733638"
     */
    public static extractId(query: string): OsmId | undefined {
        const match = query.match(OpenStreetMapIdSearch.regex)
        if (match) {
            const type = match.at(-2)
            const id = match.at(-1)
            return <OsmId>(type + "/" + id)
        }
        return undefined
    }

    async search(query: string, options?: GeocodingOptions): Promise<SearchResult[]> {
        const id = OpenStreetMapIdSearch.extractId(query)
        if (!id) {
            return []
        }
        const [osm_type, osm_id] = id.split("/")
        const obj = await this._state.osmObjectDownloader.DownloadObjectAsync(id)
        if (obj === "deleted") {
            return [{
                display_name: id + " was deleted",
                category: "coordinate",
                osm_type: <"node" | "way" | "relation">osm_type,
                osm_id,
                lat: 0, lon: 0,
                source: "osmid"

            }]
        }
        const [lat, lon] = obj.centerpoint()
        return [{
            lat, lon,
            display_name: obj.tags.name ?? obj.tags.alt_name ?? obj.tags.local_name ?? obj.tags.ref ?? id,
            osm_type: <"node" | "way" | "relation">osm_type,
            osm_id,
            source: "osmid"

        }]
    }

    suggest?(query: string, options?: GeocodingOptions): Store<SearchResult[]> {
        return UIEventSource.FromPromise(this.search(query, options))
    }

}