import { GeoOperations } from "./GeoOperations"
import { Utils } from "../Utils"
import opening_hours from "opening_hours"
import Combine from "../UI/Base/Combine"
import BaseUIElement from "../UI/BaseUIElement"
import Title from "../UI/Base/Title"
import { FixedUiElement } from "../UI/Base/FixedUiElement"
import LayerConfig from "../Models/ThemeConfig/LayerConfig"
import { CountryCoder } from "latlon2country"
import Constants from "../Models/Constants"
import { TagUtils } from "./Tags/TagUtils"
import { Feature, LineString } from "geojson"
import { OsmObject } from "./Osm/OsmObject"

export class SimpleMetaTagger {
    public readonly keys: string[]
    public readonly doc: string
    public readonly isLazy: boolean
    public readonly includesDates: boolean
    public readonly applyMetaTagsOnFeature: (
        feature: any,
        freshness: Date,
        layer: LayerConfig,
        state
    ) => boolean

    /***
     * A function that adds some extra data to a feature
     * @param docs: what does this extra data do?
     * @param f: apply the changes. Returns true if something changed
     */
    constructor(
        docs: {
            keys: string[]
            doc: string
            includesDates?: boolean
            isLazy?: boolean
            cleanupRetagger?: boolean
        },
        f: (feature: any, freshness: Date, layer: LayerConfig, state) => boolean
    ) {
        this.keys = docs.keys
        this.doc = docs.doc
        this.isLazy = docs.isLazy
        this.applyMetaTagsOnFeature = f
        this.includesDates = docs.includesDates ?? false
        if (!docs.cleanupRetagger) {
            for (const key of docs.keys) {
                if (!key.startsWith("_") && key.toLowerCase().indexOf("theme") < 0) {
                    throw `Incorrect key for a calculated meta value '${key}': it should start with underscore (_)`
                }
            }
        }
    }
}

export class CountryTagger extends SimpleMetaTagger {
    private static readonly coder = new CountryCoder(
        Constants.countryCoderEndpoint,
        Utils.downloadJson
    )
    public runningTasks: Set<any>

    constructor() {
        const runningTasks = new Set<any>()
        super(
            {
                keys: ["_country"],
                doc: "The country code of the property (with latlon2country)",
                includesDates: false,
            },
            (feature, _, __, state) => {
                let centerPoint: any = GeoOperations.centerpoint(feature)
                const lat = centerPoint.geometry.coordinates[1]
                const lon = centerPoint.geometry.coordinates[0]
                runningTasks.add(feature)
                CountryTagger.coder
                    .GetCountryCodeAsync(lon, lat)
                    .then((countries) => {
                        runningTasks.delete(feature)
                        try {
                            const oldCountry = feature.properties["_country"]
                            feature.properties["_country"] = countries[0].trim().toLowerCase()
                            if (oldCountry !== feature.properties["_country"]) {
                                const tagsSource = state?.allElements?.getEventSourceById(
                                    feature.properties.id
                                )
                                tagsSource?.ping()
                            }
                        } catch (e) {
                            console.warn(e)
                        }
                    })
                    .catch((_) => {
                        runningTasks.delete(feature)
                    })
                return false
            }
        )
        this.runningTasks = runningTasks
    }
}

export default class SimpleMetaTaggers {
    public static readonly objectMetaInfo = new SimpleMetaTagger(
        {
            keys: [
                "_last_edit:contributor",
                "_last_edit:contributor:uid",
                "_last_edit:changeset",
                "_last_edit:timestamp",
                "_version_number",
                "_backend",
            ],
            doc: "Information about the last edit of this object.",
        },
        (feature) => {
            /*Note: also called by 'UpdateTagsFromOsmAPI'*/

            const tgs = feature.properties
            let movedSomething = false;

            function move(src: string, target: string) {
                if (tgs[src] === undefined) {
                    return
                }
                tgs[target] = tgs[src]
                delete tgs[src]
                movedSomething = true
            }

            move("user", "_last_edit:contributor")
            move("uid", "_last_edit:contributor:uid")
            move("changeset", "_last_edit:changeset")
            move("timestamp", "_last_edit:timestamp")
            move("version", "_version_number")
            return movedSomething
        }
    )
    public static country = new CountryTagger()
    public static geometryType = new SimpleMetaTagger(
        {
            keys: ["_geometry:type"],
            doc: "Adds the geometry type as property. This is identical to the GoeJson geometry type and is one of `Point`,`LineString`, `Polygon` and exceptionally `MultiPolygon` or `MultiLineString`",
        },
        (feature, _) => {
            const changed = feature.properties["_geometry:type"] === feature.geometry.type
            feature.properties["_geometry:type"] = feature.geometry.type
            return changed
        }
    )
    private static readonly cardinalDirections = {
        N: 0,
        NNE: 22.5,
        NE: 45,
        ENE: 67.5,
        E: 90,
        ESE: 112.5,
        SE: 135,
        SSE: 157.5,
        S: 180,
        SSW: 202.5,
        SW: 225,
        WSW: 247.5,
        W: 270,
        WNW: 292.5,
        NW: 315,
        NNW: 337.5,
    }
    private static latlon = new SimpleMetaTagger(
        {
            keys: ["_lat", "_lon"],
            doc: "The latitude and longitude of the point (or centerpoint in the case of a way/area)",
        },
        (feature) => {
            const centerPoint = GeoOperations.centerpoint(feature)
            const lat = centerPoint.geometry.coordinates[1]
            const lon = centerPoint.geometry.coordinates[0]
            feature.properties["_lat"] = "" + lat
            feature.properties["_lon"] = "" + lon
            feature._lon = lon // This is dirty, I know
            feature._lat = lat
            return true
        }
    )
    private static layerInfo = new SimpleMetaTagger(
        {
            doc: "The layer-id to which this feature belongs. Note that this might be return any applicable if `passAllFeatures` is defined.",
            keys: ["_layer"],
            includesDates: false,
        },
        (feature, freshness, layer) => {
            if (feature.properties._layer === layer.id) {
                return false
            }
            feature.properties._layer = layer.id
            return true
        }
    )
    private static noBothButLeftRight = new SimpleMetaTagger(
        {
            keys: [
                "sidewalk:left",
                "sidewalk:right",
                "generic_key:left:property",
                "generic_key:right:property",
            ],
            doc: "Rewrites tags from 'generic_key:both:property' as 'generic_key:left:property' and 'generic_key:right:property' (and similar for sidewalk tagging). Note that this rewritten tags _will be reuploaded on a change_. To prevent to much unrelated retagging, this is only enabled if the layer has at least some lineRenderings with offset defined",
            includesDates: false,
            cleanupRetagger: true,
        },
        (feature, state, layer) => {
            if (!layer.lineRendering.some((lr) => lr.leftRightSensitive)) {
                return
            }

            return SimpleMetaTaggers.removeBothTagging(feature.properties)
        }
    )
    private static surfaceArea = new SimpleMetaTagger(
        {
            keys: ["_surface", "_surface:ha"],
            doc: "The surface area of the feature, in square meters and in hectare. Not set on points and ways",
            isLazy: true,
        },
        (feature) => {
            Object.defineProperty(feature.properties, "_surface", {
                enumerable: false,
                configurable: true,
                get: () => {
                    const sqMeters = "" + GeoOperations.surfaceAreaInSqMeters(feature)
                    delete feature.properties["_surface"]
                    feature.properties["_surface"] = sqMeters
                    return sqMeters
                },
            })

            Object.defineProperty(feature.properties, "_surface:ha", {
                enumerable: false,
                configurable: true,
                get: () => {
                    const sqMeters = GeoOperations.surfaceAreaInSqMeters(feature)
                    const sqMetersHa = "" + Math.floor(sqMeters / 1000) / 10
                    delete feature.properties["_surface:ha"]
                    feature.properties["_surface:ha"] = sqMetersHa
                    return sqMetersHa
                },
            })

            return true
        }
    )
    private static levels = new SimpleMetaTagger(
        {
            doc: "Extract the 'level'-tag into a normalized, ';'-separated value",
            keys: ["_level"],
        },
        (feature) => {
            if (feature.properties["level"] === undefined) {
                return false
            }

            const l = feature.properties["level"]
            const newValue = TagUtils.LevelsParser(l).join(";")
            if (l === newValue) {
                return false
            }
            feature.properties["level"] = newValue
            return true
        }
    )

    private static canonicalize = new SimpleMetaTagger(
        {
            doc: "If 'units' is defined in the layoutConfig, then this metatagger will rewrite the specified keys to have the canonical form (e.g. `1meter` will be rewritten to `1m`; `1` will be rewritten to `1m` as well)",
            keys: ["Theme-defined keys"],
        },
        (feature, _, __, state) => {
            const units = Utils.NoNull(
                [].concat(...(state?.layoutToUse?.layers?.map((layer) => layer.units) ?? []))
            )
            if (units.length == 0) {
                return
            }
            let rewritten = false
            for (const key in feature.properties) {
                if (!feature.properties.hasOwnProperty(key)) {
                    continue
                }
                for (const unit of units) {
                    if (unit === undefined) {
                        continue
                    }
                    if (unit.appliesToKeys === undefined) {
                        console.error("The unit ", unit, "has no appliesToKey defined")
                        continue
                    }
                    if (!unit.appliesToKeys.has(key)) {
                        continue
                    }
                    const value = feature.properties[key]
                    const denom = unit.findDenomination(value, () => feature.properties["_country"])
                    if (denom === undefined) {
                        // no valid value found
                        break
                    }
                    const [, denomination] = denom
                    const defaultDenom = unit.getDefaultDenomination(
                        () => feature.properties["_country"]
                    )
                    let canonical =
                        denomination?.canonicalValue(value, defaultDenom == denomination) ??
                        undefined
                    if (canonical === value) {
                        break
                    }
                    console.log("Rewritten ", key, ` from '${value}' into '${canonical}'`)
                    if (canonical === undefined && !unit.eraseInvalid) {
                        break
                    }

                    feature.properties[key] = canonical
                    rewritten = true
                    break
                }
            }
            return rewritten
        }
    )
    private static lngth = new SimpleMetaTagger(
        {
            keys: ["_length", "_length:km"],
            doc: "The total length of a feature in meters (and in kilometers, rounded to one decimal for '_length:km'). For a surface, the length of the perimeter",
        },
        (feature) => {
            const l = GeoOperations.lengthInMeters(feature)
            feature.properties["_length"] = "" + l
            const km = Math.floor(l / 1000)
            const kmRest = Math.round((l - km * 1000) / 100)
            feature.properties["_length:km"] = "" + km + "." + kmRest
            return true
        }
    )
    private static isOpen = new SimpleMetaTagger(
        {
            keys: ["_isOpen"],
            doc: "If 'opening_hours' is present, it will add the current state of the feature (being 'yes' or 'no')",
            includesDates: true,
            isLazy: true,
        },
        (feature, _, __, state) => {
            if (Utils.runningFromConsole) {
                // We are running from console, thus probably creating a cache
                // isOpen is irrelevant
                return false
            }
            if (feature.properties.opening_hours === "24/7") {
                feature.properties._isOpen = "yes"
                return true
            }

            // _isOpen is calculated dynamically on every call
            Object.defineProperty(feature.properties, "_isOpen", {
                enumerable: false,
                configurable: true,
                get: () => {
                    const tags = feature.properties
                    if (tags.opening_hours === undefined) {
                        return
                    }
                    if (tags._country === undefined) {
                        return
                    }

                    try {
                        const [lon, lat] = GeoOperations.centerpointCoordinates(feature)
                        const oh = new opening_hours(
                            tags["opening_hours"],
                            {
                                lat: lat,
                                lon: lon,
                                address: {
                                    country_code: tags._country.toLowerCase(),
                                    state: undefined,
                                },
                            },
                            <any>{ tag_key: "opening_hours" }
                        )

                        // Recalculate!
                        return oh.getState() ? "yes" : "no"
                    } catch (e) {
                        console.warn("Error while parsing opening hours of ", tags.id, e)
                        delete tags._isOpen
                        tags["_isOpen"] = "parse_error"
                    }
                },
            })

            const tagsSource = state.allElements.getEventSourceById(feature.properties.id)
        }
    )
    private static directionSimplified = new SimpleMetaTagger(
        {
            keys: ["_direction:numerical", "_direction:leftright"],
            doc: "_direction:numerical is a normalized, numerical direction based on 'camera:direction' or on 'direction'; it is only present if a valid direction is found (e.g. 38.5 or NE). _direction:leftright is either 'left' or 'right', which is left-looking on the map or 'right-looking' on the map",
        },
        (feature) => {
            const tags = feature.properties
            const direction = tags["camera:direction"] ?? tags["direction"]
            if (direction === undefined) {
                return false
            }
            const n = SimpleMetaTaggers.cardinalDirections[direction] ?? Number(direction)
            if (isNaN(n)) {
                return false
            }

            // The % operator has range (-360, 360). We apply a trick to get [0, 360).
            const normalized = ((n % 360) + 360) % 360

            tags["_direction:numerical"] = normalized
            tags["_direction:leftright"] = normalized <= 180 ? "right" : "left"
            return true
        }
    )

    private static directionCenterpoint = new SimpleMetaTagger(
        {
            keys: ["_direction:centerpoint"],
            isLazy: true,
            doc: "_direction:centerpoint is the direction of the linestring (in degrees) if one were standing at the projected centerpoint.",
        },
        (feature: Feature) => {
            if (feature.geometry.type !== "LineString") {
                return false
            }

            const ls = <Feature<LineString>>feature

            Object.defineProperty(feature.properties, "_direction:centerpoint", {
                enumerable: false,
                configurable: true,
                get: () => {
                    const centroid = GeoOperations.centerpoint(feature)
                    const projected = GeoOperations.nearestPoint(
                        ls,
                        <[number, number]>centroid.geometry.coordinates
                    )
                    const nextPoint = ls.geometry.coordinates[projected.properties.index + 1]
                    const bearing = GeoOperations.bearing(projected.geometry.coordinates, nextPoint)
                    delete feature.properties["_direction:centerpoint"]
                    feature.properties["_direction:centerpoint"] = bearing
                    return bearing
                },
            })

            return true
        }
    )

    private static currentTime = new SimpleMetaTagger(
        {
            keys: ["_now:date", "_now:datetime", "_loaded:date", "_loaded:_datetime"],
            doc: "Adds the time that the data got loaded - pretty much the time of downloading from overpass. The format is YYYY-MM-DD hh:mm, aka 'sortable' aka ISO-8601-but-not-entirely",
            includesDates: true,
        },
        (feature, freshness) => {
            const now = new Date()

            if (typeof freshness === "string") {
                freshness = new Date(freshness)
            }

            function date(d: Date) {
                return d.toISOString().slice(0, 10)
            }

            function datetime(d: Date) {
                return d.toISOString().slice(0, -5).replace("T", " ")
            }

            feature.properties["_now:date"] = date(now)
            feature.properties["_now:datetime"] = datetime(now)
            feature.properties["_loaded:date"] = date(freshness)
            feature.properties["_loaded:datetime"] = datetime(freshness)
            return true
        }
    )

    public static referencingWays = new SimpleMetaTagger(
        {
            keys: ["_referencing_ways"],
            isLazy: true,
            doc: "_referencing_ways contains - for a node - which ways use this this node as point in their geometry. ",
        },
        (feature, _, __, state) => {
            //this function has some extra code to make it work in SimpleAddUI.ts to also work for newly added points
            const id = feature.properties.id
            if (!id.startsWith("node/")) {
                return false
            }
            OsmObject.DownloadReferencingWays(id).then((referencingWays) => {
                const currentTagsSource = state.allElements?.getEventSourceById(id) ?? []
                const wayIds = referencingWays.map((w) => "way/" + w.id)
                wayIds.sort()
                const wayIdsStr = wayIds.join(";")
                if (wayIdsStr !== "" && currentTagsSource.data["_referencing_ways"] !== wayIdsStr) {
                    currentTagsSource.data["_referencing_ways"] = wayIdsStr
                    currentTagsSource.ping()
                }
            })

            return true
        }
    )

    public static metatags: SimpleMetaTagger[] = [
        SimpleMetaTaggers.latlon,
        SimpleMetaTaggers.layerInfo,
        SimpleMetaTaggers.surfaceArea,
        SimpleMetaTaggers.lngth,
        SimpleMetaTaggers.canonicalize,
        SimpleMetaTaggers.country,
        SimpleMetaTaggers.isOpen,
        SimpleMetaTaggers.directionSimplified,
        SimpleMetaTaggers.directionCenterpoint,
        SimpleMetaTaggers.currentTime,
        SimpleMetaTaggers.objectMetaInfo,
        SimpleMetaTaggers.noBothButLeftRight,
        SimpleMetaTaggers.geometryType,
        SimpleMetaTaggers.levels,
        SimpleMetaTaggers.referencingWays,
    ]
    public static readonly lazyTags: string[] = [].concat(
        ...SimpleMetaTaggers.metatags.filter((tagger) => tagger.isLazy).map((tagger) => tagger.keys)
    )

    /**
     * Edits the given object to rewrite 'both'-tagging into a 'left-right' tagging scheme.
     * These changes are performed in-place.
     *
     * Returns 'true' is at least one change has been made
     * @param tags
     */
    public static removeBothTagging(tags: any): boolean {
        let somethingChanged = false

        /**
         * Sets the key onto the properties (but doesn't overwrite if already existing)
         */
        function set(k, value) {
            if (tags[k] === undefined || tags[k] === "") {
                tags[k] = value
                somethingChanged = true
            }
        }

        if (tags["sidewalk"]) {
            const v = tags["sidewalk"]
            switch (v) {
                case "none":
                case "no":
                    set("sidewalk:left", "no")
                    set("sidewalk:right", "no")
                    break
                case "both":
                    set("sidewalk:left", "yes")
                    set("sidewalk:right", "yes")
                    break
                case "left":
                    set("sidewalk:left", "yes")
                    set("sidewalk:right", "no")
                    break
                case "right":
                    set("sidewalk:left", "no")
                    set("sidewalk:right", "yes")
                    break
                default:
                    set("sidewalk:left", v)
                    set("sidewalk:right", v)
                    break
            }
            delete tags["sidewalk"]
            somethingChanged = true
        }

        const regex = /\([^:]*\):both:\(.*\)/
        for (const key in tags) {
            const v = tags[key]
            if (key.endsWith(":both")) {
                const strippedKey = key.substring(0, key.length - ":both".length)
                set(strippedKey + ":left", v)
                set(strippedKey + ":right", v)
                delete tags[key]
                continue
            }

            const match = key.match(regex)
            if (match !== null) {
                const strippedKey = match[1]
                const property = match[1]
                set(strippedKey + ":left:" + property, v)
                set(strippedKey + ":right:" + property, v)
                console.log("Left-right rewritten " + key)
                delete tags[key]
            }
        }

        return somethingChanged
    }

    public static HelpText(): BaseUIElement {
        const subElements: (string | BaseUIElement)[] = [
            new Combine([
                "Metatags are extra tags available, in order to display more data or to give better questions.",
                "They are calculated automatically on every feature when the data arrives in the webbrowser. This document gives an overview of the available metatags.",
                "**Hint:** when using metatags, add the [query parameter](URL_Parameters.md) `debug=true` to the URL. This will include a box in the popup for features which shows all the properties of the object",
            ]).SetClass("flex-col"),
        ]

        subElements.push(new Title("Metatags calculated by MapComplete", 2))
        subElements.push(
            new FixedUiElement(
                "The following values are always calculated, by default, by MapComplete and are available automatically on all elements in every theme"
            )
        )
        for (const metatag of SimpleMetaTaggers.metatags) {
            subElements.push(
                new Title(metatag.keys.join(", "), 3),
                metatag.doc,
                metatag.isLazy ? "This is a lazy metatag and is only calculated when needed" : ""
            )
        }

        return new Combine(subElements).SetClass("flex-col")
    }
}