/**
 * @module helpers
 */
/**
 * Earth Radius used with the Harvesine formula and approximates using a spherical (non-ellipsoid) Earth.
 *
 * @memberof helpers
 * @type {number}
 */
export var earthRadius = 6371008.8;
/**
 * Unit of measurement factors using a spherical (non-ellipsoid) earth radius.
 *
 * @memberof helpers
 * @type {Object}
 */
export var factors = {
    centimeters: earthRadius * 100,
    centimetres: earthRadius * 100,
    degrees: earthRadius / 111325,
    feet: earthRadius * 3.28084,
    inches: earthRadius * 39.37,
    kilometers: earthRadius / 1000,
    kilometres: earthRadius / 1000,
    meters: earthRadius,
    metres: earthRadius,
    miles: earthRadius / 1609.344,
    millimeters: earthRadius * 1000,
    millimetres: earthRadius * 1000,
    nauticalmiles: earthRadius / 1852,
    radians: 1,
    yards: earthRadius * 1.0936,
};
/**
 * Units of measurement factors based on 1 meter.
 *
 * @memberof helpers
 * @type {Object}
 */
export var unitsFactors = {
    centimeters: 100,
    centimetres: 100,
    degrees: 1 / 111325,
    feet: 3.28084,
    inches: 39.37,
    kilometers: 1 / 1000,
    kilometres: 1 / 1000,
    meters: 1,
    metres: 1,
    miles: 1 / 1609.344,
    millimeters: 1000,
    millimetres: 1000,
    nauticalmiles: 1 / 1852,
    radians: 1 / earthRadius,
    yards: 1.0936133,
};
/**
 * Area of measurement factors based on 1 square meter.
 *
 * @memberof helpers
 * @type {Object}
 */
export var areaFactors = {
    acres: 0.000247105,
    centimeters: 10000,
    centimetres: 10000,
    feet: 10.763910417,
    hectares: 0.0001,
    inches: 1550.003100006,
    kilometers: 0.000001,
    kilometres: 0.000001,
    meters: 1,
    metres: 1,
    miles: 3.86e-7,
    millimeters: 1000000,
    millimetres: 1000000,
    yards: 1.195990046,
};
/**
 * Wraps a GeoJSON {@link Geometry} in a GeoJSON {@link Feature}.
 *
 * @name feature
 * @param {Geometry} geometry input geometry
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature} a GeoJSON Feature
 * @example
 * var geometry = {
 *   "type": "Point",
 *   "coordinates": [110, 50]
 * };
 *
 * var feature = turf.feature(geometry);
 *
 * //=feature
 */
export function feature(geom, properties, options) {
    if (options === void 0) { options = {}; }
    var feat = { type: "Feature" };
    if (options.id === 0 || options.id) {
        feat.id = options.id;
    }
    if (options.bbox) {
        feat.bbox = options.bbox;
    }
    feat.properties = properties || {};
    feat.geometry = geom;
    return feat;
}
/**
 * Creates a GeoJSON {@link Geometry} from a Geometry string type & coordinates.
 * For GeometryCollection type use `helpers.geometryCollection`
 *
 * @name geometry
 * @param {string} type Geometry Type
 * @param {Array<any>} coordinates Coordinates
 * @param {Object} [options={}] Optional Parameters
 * @returns {Geometry} a GeoJSON Geometry
 * @example
 * var type = "Point";
 * var coordinates = [110, 50];
 * var geometry = turf.geometry(type, coordinates);
 * // => geometry
 */
export function geometry(type, coordinates, _options) {
    if (_options === void 0) { _options = {}; }
    switch (type) {
        case "Point":
            return point(coordinates).geometry;
        case "LineString":
            return lineString(coordinates).geometry;
        case "Polygon":
            return polygon(coordinates).geometry;
        case "MultiPoint":
            return multiPoint(coordinates).geometry;
        case "MultiLineString":
            return multiLineString(coordinates).geometry;
        case "MultiPolygon":
            return multiPolygon(coordinates).geometry;
        default:
            throw new Error(type + " is invalid");
    }
}
/**
 * Creates a {@link Point} {@link Feature} from a Position.
 *
 * @name point
 * @param {Array<number>} coordinates longitude, latitude position (each in decimal degrees)
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature<Point>} a Point feature
 * @example
 * var point = turf.point([-75.343, 39.984]);
 *
 * //=point
 */
export function point(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    if (!coordinates) {
        throw new Error("coordinates is required");
    }
    if (!Array.isArray(coordinates)) {
        throw new Error("coordinates must be an Array");
    }
    if (coordinates.length < 2) {
        throw new Error("coordinates must be at least 2 numbers long");
    }
    if (!isNumber(coordinates[0]) || !isNumber(coordinates[1])) {
        throw new Error("coordinates must contain numbers");
    }
    var geom = {
        type: "Point",
        coordinates: coordinates,
    };
    return feature(geom, properties, options);
}
/**
 * Creates a {@link Point} {@link FeatureCollection} from an Array of Point coordinates.
 *
 * @name points
 * @param {Array<Array<number>>} coordinates an array of Points
 * @param {Object} [properties={}] Translate these properties to each Feature
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north]
 * associated with the FeatureCollection
 * @param {string|number} [options.id] Identifier associated with the FeatureCollection
 * @returns {FeatureCollection<Point>} Point Feature
 * @example
 * var points = turf.points([
 *   [-75, 39],
 *   [-80, 45],
 *   [-78, 50]
 * ]);
 *
 * //=points
 */
export function points(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    return featureCollection(coordinates.map(function (coords) {
        return point(coords, properties);
    }), options);
}
/**
 * Creates a {@link Polygon} {@link Feature} from an Array of LinearRings.
 *
 * @name polygon
 * @param {Array<Array<Array<number>>>} coordinates an array of LinearRings
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature<Polygon>} Polygon Feature
 * @example
 * var polygon = turf.polygon([[[-5, 52], [-4, 56], [-2, 51], [-7, 54], [-5, 52]]], { name: 'poly1' });
 *
 * //=polygon
 */
export function polygon(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    for (var _i = 0, coordinates_1 = coordinates; _i < coordinates_1.length; _i++) {
        var ring = coordinates_1[_i];
        if (ring.length < 4) {
            throw new Error("Each LinearRing of a Polygon must have 4 or more Positions.");
        }
        for (var j = 0; j < ring[ring.length - 1].length; j++) {
            // Check if first point of Polygon contains two numbers
            if (ring[ring.length - 1][j] !== ring[0][j]) {
                throw new Error("First and last Position are not equivalent.");
            }
        }
    }
    var geom = {
        type: "Polygon",
        coordinates: coordinates,
    };
    return feature(geom, properties, options);
}
/**
 * Creates a {@link Polygon} {@link FeatureCollection} from an Array of Polygon coordinates.
 *
 * @name polygons
 * @param {Array<Array<Array<Array<number>>>>} coordinates an array of Polygon coordinates
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the FeatureCollection
 * @returns {FeatureCollection<Polygon>} Polygon FeatureCollection
 * @example
 * var polygons = turf.polygons([
 *   [[[-5, 52], [-4, 56], [-2, 51], [-7, 54], [-5, 52]]],
 *   [[[-15, 42], [-14, 46], [-12, 41], [-17, 44], [-15, 42]]],
 * ]);
 *
 * //=polygons
 */
export function polygons(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    return featureCollection(coordinates.map(function (coords) {
        return polygon(coords, properties);
    }), options);
}
/**
 * Creates a {@link LineString} {@link Feature} from an Array of Positions.
 *
 * @name lineString
 * @param {Array<Array<number>>} coordinates an array of Positions
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature<LineString>} LineString Feature
 * @example
 * var linestring1 = turf.lineString([[-24, 63], [-23, 60], [-25, 65], [-20, 69]], {name: 'line 1'});
 * var linestring2 = turf.lineString([[-14, 43], [-13, 40], [-15, 45], [-10, 49]], {name: 'line 2'});
 *
 * //=linestring1
 * //=linestring2
 */
export function lineString(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    if (coordinates.length < 2) {
        throw new Error("coordinates must be an array of two or more positions");
    }
    var geom = {
        type: "LineString",
        coordinates: coordinates,
    };
    return feature(geom, properties, options);
}
/**
 * Creates a {@link LineString} {@link FeatureCollection} from an Array of LineString coordinates.
 *
 * @name lineStrings
 * @param {Array<Array<Array<number>>>} coordinates an array of LinearRings
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north]
 * associated with the FeatureCollection
 * @param {string|number} [options.id] Identifier associated with the FeatureCollection
 * @returns {FeatureCollection<LineString>} LineString FeatureCollection
 * @example
 * var linestrings = turf.lineStrings([
 *   [[-24, 63], [-23, 60], [-25, 65], [-20, 69]],
 *   [[-14, 43], [-13, 40], [-15, 45], [-10, 49]]
 * ]);
 *
 * //=linestrings
 */
export function lineStrings(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    return featureCollection(coordinates.map(function (coords) {
        return lineString(coords, properties);
    }), options);
}
/**
 * Takes one or more {@link Feature|Features} and creates a {@link FeatureCollection}.
 *
 * @name featureCollection
 * @param {Feature[]} features input features
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {FeatureCollection} FeatureCollection of Features
 * @example
 * var locationA = turf.point([-75.343, 39.984], {name: 'Location A'});
 * var locationB = turf.point([-75.833, 39.284], {name: 'Location B'});
 * var locationC = turf.point([-75.534, 39.123], {name: 'Location C'});
 *
 * var collection = turf.featureCollection([
 *   locationA,
 *   locationB,
 *   locationC
 * ]);
 *
 * //=collection
 */
export function featureCollection(features, options) {
    if (options === void 0) { options = {}; }
    var fc = { type: "FeatureCollection" };
    if (options.id) {
        fc.id = options.id;
    }
    if (options.bbox) {
        fc.bbox = options.bbox;
    }
    fc.features = features;
    return fc;
}
/**
 * Creates a {@link Feature<MultiLineString>} based on a
 * coordinate array. Properties can be added optionally.
 *
 * @name multiLineString
 * @param {Array<Array<Array<number>>>} coordinates an array of LineStrings
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature<MultiLineString>} a MultiLineString feature
 * @throws {Error} if no coordinates are passed
 * @example
 * var multiLine = turf.multiLineString([[[0,0],[10,10]]]);
 *
 * //=multiLine
 */
export function multiLineString(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    var geom = {
        type: "MultiLineString",
        coordinates: coordinates,
    };
    return feature(geom, properties, options);
}
/**
 * Creates a {@link Feature<MultiPoint>} based on a
 * coordinate array. Properties can be added optionally.
 *
 * @name multiPoint
 * @param {Array<Array<number>>} coordinates an array of Positions
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature<MultiPoint>} a MultiPoint feature
 * @throws {Error} if no coordinates are passed
 * @example
 * var multiPt = turf.multiPoint([[0,0],[10,10]]);
 *
 * //=multiPt
 */
export function multiPoint(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    var geom = {
        type: "MultiPoint",
        coordinates: coordinates,
    };
    return feature(geom, properties, options);
}
/**
 * Creates a {@link Feature<MultiPolygon>} based on a
 * coordinate array. Properties can be added optionally.
 *
 * @name multiPolygon
 * @param {Array<Array<Array<Array<number>>>>} coordinates an array of Polygons
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature<MultiPolygon>} a multipolygon feature
 * @throws {Error} if no coordinates are passed
 * @example
 * var multiPoly = turf.multiPolygon([[[[0,0],[0,10],[10,10],[10,0],[0,0]]]]);
 *
 * //=multiPoly
 *
 */
export function multiPolygon(coordinates, properties, options) {
    if (options === void 0) { options = {}; }
    var geom = {
        type: "MultiPolygon",
        coordinates: coordinates,
    };
    return feature(geom, properties, options);
}
/**
 * Creates a {@link Feature<GeometryCollection>} based on a
 * coordinate array. Properties can be added optionally.
 *
 * @name geometryCollection
 * @param {Array<Geometry>} geometries an array of GeoJSON Geometries
 * @param {Object} [properties={}] an Object of key-value pairs to add as properties
 * @param {Object} [options={}] Optional Parameters
 * @param {Array<number>} [options.bbox] Bounding Box Array [west, south, east, north] associated with the Feature
 * @param {string|number} [options.id] Identifier associated with the Feature
 * @returns {Feature<GeometryCollection>} a GeoJSON GeometryCollection Feature
 * @example
 * var pt = turf.geometry("Point", [100, 0]);
 * var line = turf.geometry("LineString", [[101, 0], [102, 1]]);
 * var collection = turf.geometryCollection([pt, line]);
 *
 * // => collection
 */
export function geometryCollection(geometries, properties, options) {
    if (options === void 0) { options = {}; }
    var geom = {
        type: "GeometryCollection",
        geometries: geometries,
    };
    return feature(geom, properties, options);
}
/**
 * Round number to precision
 *
 * @param {number} num Number
 * @param {number} [precision=0] Precision
 * @returns {number} rounded number
 * @example
 * turf.round(120.4321)
 * //=120
 *
 * turf.round(120.4321, 2)
 * //=120.43
 */
export function round(num, precision) {
    if (precision === void 0) { precision = 0; }
    if (precision && !(precision >= 0)) {
        throw new Error("precision must be a positive number");
    }
    var multiplier = Math.pow(10, precision || 0);
    return Math.round(num * multiplier) / multiplier;
}
/**
 * Convert a distance measurement (assuming a spherical Earth) from radians to a more friendly unit.
 * Valid units: miles, nauticalmiles, inches, yards, meters, metres, kilometers, centimeters, feet
 *
 * @name radiansToLength
 * @param {number} radians in radians across the sphere
 * @param {string} [units="kilometers"] can be degrees, radians, miles, inches, yards, metres,
 * meters, kilometres, kilometers.
 * @returns {number} distance
 */
export function radiansToLength(radians, units) {
    if (units === void 0) { units = "kilometers"; }
    var factor = factors[units];
    if (!factor) {
        throw new Error(units + " units is invalid");
    }
    return radians * factor;
}
/**
 * Convert a distance measurement (assuming a spherical Earth) from a real-world unit into radians
 * Valid units: miles, nauticalmiles, inches, yards, meters, metres, kilometers, centimeters, feet
 *
 * @name lengthToRadians
 * @param {number} distance in real units
 * @param {string} [units="kilometers"] can be degrees, radians, miles, inches, yards, metres,
 * meters, kilometres, kilometers.
 * @returns {number} radians
 */
export function lengthToRadians(distance, units) {
    if (units === void 0) { units = "kilometers"; }
    var factor = factors[units];
    if (!factor) {
        throw new Error(units + " units is invalid");
    }
    return distance / factor;
}
/**
 * Convert a distance measurement (assuming a spherical Earth) from a real-world unit into degrees
 * Valid units: miles, nauticalmiles, inches, yards, meters, metres, centimeters, kilometres, feet
 *
 * @name lengthToDegrees
 * @param {number} distance in real units
 * @param {string} [units="kilometers"] can be degrees, radians, miles, inches, yards, metres,
 * meters, kilometres, kilometers.
 * @returns {number} degrees
 */
export function lengthToDegrees(distance, units) {
    return radiansToDegrees(lengthToRadians(distance, units));
}
/**
 * Converts any bearing angle from the north line direction (positive clockwise)
 * and returns an angle between 0-360 degrees (positive clockwise), 0 being the north line
 *
 * @name bearingToAzimuth
 * @param {number} bearing angle, between -180 and +180 degrees
 * @returns {number} angle between 0 and 360 degrees
 */
export function bearingToAzimuth(bearing) {
    var angle = bearing % 360;
    if (angle < 0) {
        angle += 360;
    }
    return angle;
}
/**
 * Converts an angle in radians to degrees
 *
 * @name radiansToDegrees
 * @param {number} radians angle in radians
 * @returns {number} degrees between 0 and 360 degrees
 */
export function radiansToDegrees(radians) {
    var degrees = radians % (2 * Math.PI);
    return (degrees * 180) / Math.PI;
}
/**
 * Converts an angle in degrees to radians
 *
 * @name degreesToRadians
 * @param {number} degrees angle between 0 and 360 degrees
 * @returns {number} angle in radians
 */
export function degreesToRadians(degrees) {
    var radians = degrees % 360;
    return (radians * Math.PI) / 180;
}
/**
 * Converts a length to the requested unit.
 * Valid units: miles, nauticalmiles, inches, yards, meters, metres, kilometers, centimeters, feet
 *
 * @param {number} length to be converted
 * @param {Units} [originalUnit="kilometers"] of the length
 * @param {Units} [finalUnit="kilometers"] returned unit
 * @returns {number} the converted length
 */
export function convertLength(length, originalUnit, finalUnit) {
    if (originalUnit === void 0) { originalUnit = "kilometers"; }
    if (finalUnit === void 0) { finalUnit = "kilometers"; }
    if (!(length >= 0)) {
        throw new Error("length must be a positive number");
    }
    return radiansToLength(lengthToRadians(length, originalUnit), finalUnit);
}
/**
 * Converts a area to the requested unit.
 * Valid units: kilometers, kilometres, meters, metres, centimetres, millimeters, acres, miles, yards, feet, inches, hectares
 * @param {number} area to be converted
 * @param {Units} [originalUnit="meters"] of the distance
 * @param {Units} [finalUnit="kilometers"] returned unit
 * @returns {number} the converted area
 */
export function convertArea(area, originalUnit, finalUnit) {
    if (originalUnit === void 0) { originalUnit = "meters"; }
    if (finalUnit === void 0) { finalUnit = "kilometers"; }
    if (!(area >= 0)) {
        throw new Error("area must be a positive number");
    }
    var startFactor = areaFactors[originalUnit];
    if (!startFactor) {
        throw new Error("invalid original units");
    }
    var finalFactor = areaFactors[finalUnit];
    if (!finalFactor) {
        throw new Error("invalid final units");
    }
    return (area / startFactor) * finalFactor;
}
/**
 * isNumber
 *
 * @param {*} num Number to validate
 * @returns {boolean} true/false
 * @example
 * turf.isNumber(123)
 * //=true
 * turf.isNumber('foo')
 * //=false
 */
export function isNumber(num) {
    return !isNaN(num) && num !== null && !Array.isArray(num);
}
/**
 * isObject
 *
 * @param {*} input variable to validate
 * @returns {boolean} true/false
 * @example
 * turf.isObject({elevation: 10})
 * //=true
 * turf.isObject('foo')
 * //=false
 */
export function isObject(input) {
    return !!input && input.constructor === Object;
}
/**
 * Validate BBox
 *
 * @private
 * @param {Array<number>} bbox BBox to validate
 * @returns {void}
 * @throws Error if BBox is not valid
 * @example
 * validateBBox([-180, -40, 110, 50])
 * //=OK
 * validateBBox([-180, -40])
 * //=Error
 * validateBBox('Foo')
 * //=Error
 * validateBBox(5)
 * //=Error
 * validateBBox(null)
 * //=Error
 * validateBBox(undefined)
 * //=Error
 */
export function validateBBox(bbox) {
    if (!bbox) {
        throw new Error("bbox is required");
    }
    if (!Array.isArray(bbox)) {
        throw new Error("bbox must be an Array");
    }
    if (bbox.length !== 4 && bbox.length !== 6) {
        throw new Error("bbox must be an Array of 4 or 6 numbers");
    }
    bbox.forEach(function (num) {
        if (!isNumber(num)) {
            throw new Error("bbox must only contain numbers");
        }
    });
}
/**
 * Validate Id
 *
 * @private
 * @param {string|number} id Id to validate
 * @returns {void}
 * @throws Error if Id is not valid
 * @example
 * validateId([-180, -40, 110, 50])
 * //=Error
 * validateId([-180, -40])
 * //=Error
 * validateId('Foo')
 * //=OK
 * validateId(5)
 * //=OK
 * validateId(null)
 * //=Error
 * validateId(undefined)
 * //=Error
 */
export function validateId(id) {
    if (!id) {
        throw new Error("id is required");
    }
    if (["string", "number"].indexOf(typeof id) === -1) {
        throw new Error("id must be a number or a string");
    }
}