// Copyright (C) 2026, Stichting Mapcode Foundation (http://www.mapcode.com)

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

import { Point } from "./point.js";

import { Boundary } from "./boundary.js";

export class MapcodeZone {

private lonFractionMin: number;

private lonFractionMax: number;

private latFractionMin: number;

private latFractionMax: number;

constructor(latFractionMin = 0.0, latFractionMax = 0.0, lonFractionMin = 0.0, lonFractionMax = 0.0) {

this.latFractionMin = latFractionMin;

this.latFractionMax = latFractionMax;

this.lonFractionMin = lonFractionMin;

this.lonFractionMax = lonFractionMax;

}

static copy(z: MapcodeZone): MapcodeZone {

return new MapcodeZone(z.latFractionMin, z.latFractionMax, z.lonFractionMin, z.lonFractionMax);

}

getLonFractionMin(): number { return this.lonFractionMin; }

getLonFractionMax(): number { return this.lonFractionMax; }

getLatFractionMin(): number { return this.latFractionMin; }

getLatFractionMax(): number { return this.latFractionMax; }

setLonFractionMin(v: number): void { this.lonFractionMin = v; }

setLonFractionMax(v: number): void { this.lonFractionMax = v; }

setLatFractionMin(v: number): void { this.latFractionMin = v; }

setLatFractionMax(v: number): void { this.latFractionMax = v; }

setFromFractions(latFraction: number, lonFraction: number, latFractionDelta: number, lonFractionDelta: number): void {

this.lonFractionMin = lonFraction;

this.lonFractionMax = lonFraction + lonFractionDelta;

if (latFractionDelta < 0) {

this.latFractionMin = latFraction + 1 + latFractionDelta;

this.latFractionMax = latFraction + 1;

} else {

this.latFractionMin = latFraction;

this.latFractionMax = latFraction + latFractionDelta;

}

}

isEmpty(): boolean {

return this.lonFractionMax <= this.lonFractionMin || this.latFractionMax <= this.latFractionMin;

}

getCenter(): Point {

if (this.isEmpty()) return Point.undefined();

const latFrac = Math.floor((this.latFractionMin + this.latFractionMax) / 2.0);

const lonFrac = Math.floor((this.lonFractionMin + this.lonFractionMax) / 2.0);

return Point.fromLatLonFractions(latFrac, lonFrac);

}

restrictZoneTo(area: Boundary): MapcodeZone {

const z = new MapcodeZone(this.latFractionMin, this.latFractionMax, this.lonFractionMin, this.lonFractionMax);

const latMin = area.getLatMicroDegMin() * Point.LAT_MICRODEG_TO_FRACTIONS_FACTOR;

if (z.latFractionMin < latMin) z.latFractionMin = latMin;

const latMax = area.getLatMicroDegMax() * Point.LAT_MICRODEG_TO_FRACTIONS_FACTOR;

if (z.latFractionMax > latMax) z.latFractionMax = latMax;

if (z.latFractionMin < z.latFractionMax) {

let lonMin = area.getLonMicroDegMin() * Point.LON_MICRODEG_TO_FRACTIONS_FACTOR;

let lonMax = area.getLonMicroDegMax() * Point.LON_MICRODEG_TO_FRACTIONS_FACTOR;

if (lonMax < 0 && z.lonFractionMin > 0) {

lonMin += Point.MICRO_DEG_360 * Point.LON_MICRODEG_TO_FRACTIONS_FACTOR;

lonMax += Point.MICRO_DEG_360 * Point.LON_MICRODEG_TO_FRACTIONS_FACTOR;

} else if (lonMin > 1 && z.lonFractionMax < 0) {

lonMin -= Point.MICRO_DEG_360 * Point.LON_MICRODEG_TO_FRACTIONS_FACTOR;

lonMax -= Point.MICRO_DEG_360 * Point.LON_MICRODEG_TO_FRACTIONS_FACTOR;

}

if (z.lonFractionMin < lonMin) z.lonFractionMin = lonMin;

if (z.lonFractionMax > lonMax) z.lonFractionMax = lonMax;

}

return z;

}

toString(): string {

return this.isEmpty() ? "empty" :

`[${this.latFractionMin / Point.LAT_TO_FRACTIONS_FACTOR}, ${this.latFractionMax / Point.LAT_TO_FRACTIONS_FACTOR}), [` +

`${this.lonFractionMin / Point.LON_TO_FRACTIONS_FACTOR}, ${this.lonFractionMax / Point.LON_TO_FRACTIONS_FACTOR})`;

}

}