import { BoundingBox, Coordinates } from "@wemap/geo";

export const defaultBounds = new BoundingBox(
    new Coordinates(85, 170),
    new Coordinates(-85, -170)
);

export const correctBounds = (bounds: BoundingBox) => {
    const southWest = bounds.getSouthWest();
    const northEast = bounds.getNorthEast();
    const south = southWest.lat;
    let west = southWest.lng;

    const north = northEast.lat;
    const east = northEast.lng;

    // If bounding box cross the meridian
    // e.g. west longitude 177 become -183
    const crossMeridian = west > east;
    if (crossMeridian) {
        west = -(180 - west + 180);
    }

    const northEastCorrected = new Coordinates(0, 0);
    northEastCorrected.autoWrap = false;

    northEastCorrected.lat = north;
    northEastCorrected.lng = east;

    const southWestCorrected = new Coordinates(0, 0);
    southWestCorrected.autoWrap = false;

    southWestCorrected.lat = south;
    southWestCorrected.lng = west;

    return new BoundingBox(northEastCorrected, southWestCorrected);
};

export const deltaToBounds = (coords?: {
    latitude: number;
    longitude: number;
    latitude_delta: number;
    longitude_delta: number;
} | null) => {

    if (!coords) {
        return defaultBounds;
    }

    const southWest = new Coordinates(
        Number(coords.latitude) - Number(coords.latitude_delta),
        Number(coords.longitude) - Number(coords.longitude_delta)
    );

    const northEast = new Coordinates(
        Number(coords.latitude) + Number(coords.latitude_delta),
        Number(coords.longitude) + Number(coords.longitude_delta)
    );

    return correctBounds(new BoundingBox(northEast, southWest));
};