Cesium-Examples/libs/shapefile/shapefile.js

/*!
 * shapefile Version 0.6.6(https://github.com/mbostock/shapefile)
 * Copyright 2017 Mike Bostock.
 * mbostock/shapefile is licensed under the BSD 3-clause "New" or "Revised" License
 */
(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
        typeof define === 'function' && define.amd ? define(['exports'], factory) :
            (factory((global.shapefile = {})));
}(this, (function (exports) { 'use strict';

    var array_cancel = function() {
        this._array = null;
        return Promise.resolve();
    };

    var array_read = function() {
        var array = this._array;
        this._array = null;
        return Promise.resolve(array ? {done: false, value: array} : {done: true, value: undefined});
    };

    function array(array) {
        return new ArraySource(array instanceof Uint8Array ? array : new Uint8Array(array));
    }

    function ArraySource(array) {
        this._array = array;
    }

    ArraySource.prototype.read = array_read;
    ArraySource.prototype.cancel = array_cancel;

    var fetchPath = function(url) {
        return fetch(url).then(function(response) {
            return response.body && response.body.getReader
                ? response.body.getReader()
                : response.arrayBuffer().then(array);
        });
    };

    var requestPath = function(url) {
        return new Promise(function(resolve, reject) {
            var request = new XMLHttpRequest;
            request.responseType = "arraybuffer";
            request.onload = function() { resolve(array(request.response)); };
            request.onerror = reject;
            request.ontimeout = reject;
            request.open("GET", url, true);
            request.send();
        });
    };

    function path(path) {
        return (typeof fetch === "function" ? fetchPath : requestPath)(path);
    }

    function stream(source) {
        return typeof source.read === "function" ? source : source.getReader();
    }

    var empty = new Uint8Array(0);

    var slice_cancel = function() {
        return this._source.cancel();
    };

    function concat(a, b) {
        if (!a.length) return b;
        if (!b.length) return a;
        var c = new Uint8Array(a.length + b.length);
        c.set(a);
        c.set(b, a.length);
        return c;
    }

    var slice_read = function() {
        var that = this, array = that._array.subarray(that._index);
        return that._source.read().then(function(result) {
            that._array = empty;
            that._index = 0;
            return result.done ? (array.length > 0
                ? {done: false, value: array}
                : {done: true, value: undefined})
                : {done: false, value: concat(array, result.value)};
        });
    };

    var slice_slice = function(length) {
        if ((length |= 0) < 0) throw new Error("invalid length");
        var that = this, index = this._array.length - this._index;

        // If the request fits within the remaining buffer, resolve it immediately.
        if (this._index + length <= this._array.length) {
            return Promise.resolve(this._array.subarray(this._index, this._index += length));
        }

        // Otherwise, read chunks repeatedly until the request is fulfilled.
        var array = new Uint8Array(length);
        array.set(this._array.subarray(this._index));
        return (function read() {
            return that._source.read().then(function(result) {

                // When done, it鈥檚 possible the request wasn鈥檛 fully fullfilled!
                // If so, the pre-allocated array is too big and needs slicing.
                if (result.done) {
                    that._array = empty;
                    that._index = 0;
                    return index > 0 ? array.subarray(0, index) : null;
                }

                // If this chunk fulfills the request, return the resulting array.
                if (index + result.value.length >= length) {
                    that._array = result.value;
                    that._index = length - index;
                    array.set(result.value.subarray(0, length - index), index);
                    return array;
                }

                // Otherwise copy this chunk into the array, then read the next chunk.
                array.set(result.value, index);
                index += result.value.length;
                return read();
            });
        })();
    };

    function slice(source) {
        return typeof source.slice === "function" ? source :
            new SliceSource(typeof source.read === "function" ? source
                : source.getReader());
    }

    function SliceSource(source) {
        this._source = source;
        this._array = empty;
        this._index = 0;
    }

    SliceSource.prototype.read = slice_read;
    SliceSource.prototype.slice = slice_slice;
    SliceSource.prototype.cancel = slice_cancel;

    var dbf_cancel = function() {
        return this._source.cancel();
    };

    var readBoolean = function(value) {
        return /^[nf]$/i.test(value) ? false
            : /^[yt]$/i.test(value) ? true
                : null;
    };

    var readDate = function(value) {
        return new Date(+value.substring(0, 4), value.substring(4, 6) - 1, +value.substring(6, 8));
    };

    var readNumber = function(value) {
        return !(value = value.trim()) || isNaN(value = +value) ? null : value;
    };

    var readString = function(value) {
        return value.trim() || null;
    };

    var types = {
        B: readNumber,
        C: readString,
        D: readDate,
        F: readNumber,
        L: readBoolean,
        M: readNumber,
        N: readNumber
    };

    var dbf_read = function() {
        var that = this, i = 1;
        return that._source.slice(that._recordLength).then(function(value) {
            return value && (value[0] !== 0x1a) ? {done: false, value: that._fields.reduce(function(p, f) {
                p[f.name] = types[f.type](that._decode(value.subarray(i, i += f.length)));
                return p;
            }, {})} : {done: true, value: undefined};
        });
    };

    var view = function(array) {
        return new DataView(array.buffer, array.byteOffset, array.byteLength);
    };

    var dbf = function(source, decoder) {
        source = slice(source);
        return source.slice(32).then(function(array) {
            var head = view(array);
            return source.slice(head.getUint16(8, true) - 32).then(function(array) {
                return new Dbf(source, decoder, head, view(array));
            });
        });
    };

    function Dbf(source, decoder, head, body) {
        this._source = source;
        this._decode = decoder.decode.bind(decoder);
        this._recordLength = head.getUint16(10, true);
        this._fields = [];
        for (var n = 0; body.getUint8(n) !== 0x0d; n += 32) {
            for (var j = 0; j < 11; ++j) if (body.getUint8(n + j) === 0) break;
            this._fields.push({
                name: this._decode(new Uint8Array(body.buffer, body.byteOffset + n, j)),
                type: String.fromCharCode(body.getUint8(n + 11)),
                length: body.getUint8(n + 16)
            });
        }
    }

    var prototype = Dbf.prototype;
    prototype.read = dbf_read;
    prototype.cancel = dbf_cancel;

    function cancel() {
        return this._source.cancel();
    }

    var parseMultiPoint = function(record) {
        var i = 40, j, n = record.getInt32(36, true), coordinates = new Array(n);
        for (j = 0; j < n; ++j, i += 16) coordinates[j] = [record.getFloat64(i, true), record.getFloat64(i + 8, true)];
        return {type: "MultiPoint", coordinates: coordinates};
    };

    var parseNull = function() {
        return null;
    };

    var parsePoint = function(record) {
        return {type: "Point", coordinates: [record.getFloat64(4, true), record.getFloat64(12, true)]};
    };

    var parsePolygon = function(record) {
        var i = 44, j, n = record.getInt32(36, true), m = record.getInt32(40, true), parts = new Array(n), points = new Array(m), polygons = [], holes = [];
        for (j = 0; j < n; ++j, i += 4) parts[j] = record.getInt32(i, true);
        for (j = 0; j < m; ++j, i += 16) points[j] = [record.getFloat64(i, true), record.getFloat64(i + 8, true)];

        parts.forEach(function(i, j) {
            var ring = points.slice(i, parts[j + 1]);
            if (ringClockwise(ring)) polygons.push([ring]);
            else holes.push(ring);
        });

        holes.forEach(function(hole) {
            polygons.some(function(polygon) {
                if (ringContainsSome(polygon[0], hole)) {
                    polygon.push(hole);
                    return true;
                }
            }) || polygons.push([hole]);
        });

        return polygons.length === 1
            ? {type: "Polygon", coordinates: polygons[0]}
            : {type: "MultiPolygon", coordinates: polygons};
    };

    function ringClockwise(ring) {
        if ((n = ring.length) < 4) return false;
        var i = 0, n, area = ring[n - 1][1] * ring[0][0] - ring[n - 1][0] * ring[0][1];
        while (++i < n) area += ring[i - 1][1] * ring[i][0] - ring[i - 1][0] * ring[i][1];
        return area >= 0;
    }

    function ringContainsSome(ring, hole) {
        var i = -1, n = hole.length, c;
        while (++i < n) {
            if (c = ringContains(ring, hole[i])) {
                return c > 0;
            }
        }
        return false;
    }

    function ringContains(ring, point) {
        var x = point[0], y = point[1], contains = -1;
        for (var i = 0, n = ring.length, j = n - 1; i < n; j = i++) {
            var pi = ring[i], xi = pi[0], yi = pi[1],
                pj = ring[j], xj = pj[0], yj = pj[1];
            if (segmentContains(pi, pj, point)) {
                return 0;
            }
            if (((yi > y) !== (yj > y)) && ((x < (xj - xi) * (y - yi) / (yj - yi) + xi))) {
                contains = -contains;
            }
        }
        return contains;
    }

    function segmentContains(p0, p1, p2) {
        var x20 = p2[0] - p0[0], y20 = p2[1] - p0[1];
        if (x20 === 0 && y20 === 0) return true;
        var x10 = p1[0] - p0[0], y10 = p1[1] - p0[1];
        if (x10 === 0 && y10 === 0) return false;
        var t = (x20 * x10 + y20 * y10) / (x10 * x10 + y10 * y10);
        return t < 0 || t > 1 ? false : t === 0 || t === 1 ? true : t * x10 === x20 && t * y10 === y20;
    }

    var parsePolyLine = function(record) {
        var i = 44, j, n = record.getInt32(36, true), m = record.getInt32(40, true), parts = new Array(n), points = new Array(m);
        for (j = 0; j < n; ++j, i += 4) parts[j] = record.getInt32(i, true);
        for (j = 0; j < m; ++j, i += 16) points[j] = [record.getFloat64(i, true), record.getFloat64(i + 8, true)];
        return n === 1
            ? {type: "LineString", coordinates: points}
            : {type: "MultiLineString", coordinates: parts.map(function(i, j) { return points.slice(i, parts[j + 1]); })};
    };

    var concat$1 = function(a, b) {
        var ab = new Uint8Array(a.length + b.length);
        ab.set(a, 0);
        ab.set(b, a.length);
        return ab;
    };

    var shp_read = function() {
        var that = this;
        ++that._index;
        return that._source.slice(12).then(function(array) {
            if (array == null) return {done: true, value: undefined};
            var header = view(array);

            // If the record starts with an invalid shape type (see #36), scan ahead in
            // four-byte increments to find the next valid record, identified by the
            // expected index, a non-empty content length and a valid shape type.
            function skip() {
                return that._source.slice(4).then(function(chunk) {
                    if (chunk == null) return {done: true, value: undefined};
                    header = view(array = concat$1(array.slice(4), chunk));
                    return header.getInt32(0, false) !== that._index ? skip() : read();
                });
            }

            // All records should have at least four bytes (for the record shape type),
            // so an invalid content length indicates corruption.
            function read() {
                var length = header.getInt32(4, false) * 2 - 4, type = header.getInt32(8, true);
                return length < 0 || (type && type !== that._type) ? skip() : that._source.slice(length).then(function(chunk) {
                    return {done: false, value: type ? that._parse(view(concat$1(array.slice(8), chunk))) : null};
                });
            }

            return read();
        });
    };

    var parsers = {
        0: parseNull,
        1: parsePoint,
        3: parsePolyLine,
        5: parsePolygon,
        8: parseMultiPoint,
        11: parsePoint, // PointZ
        13: parsePolyLine, // PolyLineZ
        15: parsePolygon, // PolygonZ
        18: parseMultiPoint, // MultiPointZ
        21: parsePoint, // PointM
        23: parsePolyLine, // PolyLineM
        25: parsePolygon, // PolygonM
        28: parseMultiPoint // MultiPointM
    };

    var shp = function(source) {
        source = slice(source);
        return source.slice(100).then(function(array) {
            return new Shp(source, view(array));
        });
    };

    function Shp(source, header) {
        var type = header.getInt32(32, true);
        if (!(type in parsers)) throw new Error("unsupported shape type: " + type);
        this._source = source;
        this._type = type;
        this._index = 0;
        this._parse = parsers[type];
        this.bbox = [header.getFloat64(36, true), header.getFloat64(44, true), header.getFloat64(52, true), header.getFloat64(60, true)];
    }

    var prototype$2 = Shp.prototype;
    prototype$2.read = shp_read;
    prototype$2.cancel = cancel;

    function noop() {}

    var shapefile_cancel = function() {
        return Promise.all([
            this._dbf && this._dbf.cancel(),
            this._shp.cancel()
        ]).then(noop);
    };

    var shapefile_read = function() {
        var that = this;
        return Promise.all([
            that._dbf ? that._dbf.read() : {value: {}},
            that._shp.read()
        ]).then(function(results) {
            var dbf = results[0], shp = results[1];
            return shp.done ? shp : {
                done: false,
                value: {
                    type: "Feature",
                    properties: dbf.value,
                    geometry: shp.value
                }
            };
        });
    };

    var shapefile = function(shpSource, dbfSource, decoder) {
        return Promise.all([
            shp(shpSource),
            dbfSource && dbf(dbfSource, decoder)
        ]).then(function(sources) {
            return new Shapefile(sources[0], sources[1]);
        });
    };

    function Shapefile(shp$$1, dbf$$1) {
        this._shp = shp$$1;
        this._dbf = dbf$$1;
        this.bbox = shp$$1.bbox;
    }

    var prototype$1 = Shapefile.prototype;
    prototype$1.read = shapefile_read;
    prototype$1.cancel = shapefile_cancel;

    function open(shp$$1, dbf$$1, options) {
        if (typeof dbf$$1 === "string") {
            if (!/\.dbf$/.test(dbf$$1)) dbf$$1 += ".dbf";
            dbf$$1 = path(dbf$$1, options);
        } else if (dbf$$1 instanceof ArrayBuffer || dbf$$1 instanceof Uint8Array) {
            dbf$$1 = array(dbf$$1);
        } else if (dbf$$1 != null) {
            dbf$$1 = stream(dbf$$1);
        }
        if (typeof shp$$1 === "string") {
            if (!/\.shp$/.test(shp$$1)) shp$$1 += ".shp";
            if (dbf$$1 === undefined) dbf$$1 = path(shp$$1.substring(0, shp$$1.length - 4) + ".dbf", options).catch(function() {});
            shp$$1 = path(shp$$1, options);
        } else if (shp$$1 instanceof ArrayBuffer || shp$$1 instanceof Uint8Array) {
            shp$$1 = array(shp$$1);
        } else {
            shp$$1 = stream(shp$$1);
        }
        return Promise.all([shp$$1, dbf$$1]).then(function(sources) {
            var shp$$1 = sources[0], dbf$$1 = sources[1], encoding = "windows-1252";
            if (options && options.encoding != null) encoding = options.encoding;
            return shapefile(shp$$1, dbf$$1, dbf$$1 && new TextDecoder(encoding));
        });
    }

    function openShp(source, options) {
        if (typeof source === "string") {
            if (!/\.shp$/.test(source)) source += ".shp";
            source = path(source, options);
        } else if (source instanceof ArrayBuffer || source instanceof Uint8Array) {
            source = array(source);
        } else {
            source = stream(source);
        }
        return Promise.resolve(source).then(shp);
    }

    function openDbf(source, options) {
        var encoding = "windows-1252";
        if (options && options.encoding != null) encoding = options.encoding;
        encoding = new TextDecoder(encoding);
        if (typeof source === "string") {
            if (!/\.dbf$/.test(source)) source += ".dbf";
            source = path(source, options);
        } else if (source instanceof ArrayBuffer || source instanceof Uint8Array) {
            source = array(source);
        } else {
            source = stream(source);
        }
        return Promise.resolve(source).then(function(source) {
            return dbf(source, encoding);
        });
    }

    function read(shp$$1, dbf$$1, options) {
        return open(shp$$1, dbf$$1, options).then(function(source) {
            var features = [], collection = {type: "FeatureCollection", features: features, bbox: source.bbox};
            return source.read().then(function read(result) {
                if (result.done) return collection;
                features.push(result.value);
                return source.read().then(read);
            });
        });
    }

    exports.open = open;
    exports.openShp = openShp;
    exports.openDbf = openDbf;
    exports.read = read;

    Object.defineProperty(exports, '__esModule', { value: true });

})));