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Your IP : 3.15.18.157
'use strict'
/* const FIGURE = {
INTERIOR_RING: 0x00,
STROKE: 0x01,
EXTERIOR_RING: 0x02
};
const FIGURE_V2 = {
POINT: 0x00,
LINE: 0x01,
ARC: 0x02,
COMPOSITE_CURVE: 0x03
};
const SHAPE = {
POINT: 0x01,
LINESTRING: 0x02,
POLYGON: 0x03,
MULTIPOINT: 0x04,
MULTILINESTRING: 0x05,
MULTIPOLYGON: 0x06,
GEOMETRY_COLLECTION: 0x07
};
const SHAPE_V2 = {
POINT: 0x01,
LINESTRING: 0x02,
POLYGON: 0x03,
MULTIPOINT: 0x04,
MULTILINESTRING: 0x05,
MULTIPOLYGON: 0x06,
GEOMETRY_COLLECTION: 0x07,
CIRCULAR_STRING: 0x08,
COMPOUND_CURVE: 0x09,
CURVE_POLYGON: 0x0A,
FULL_GLOBE: 0x0B
};
const SEGMENT = {
LINE: 0x00,
ARC: 0x01,
FIRST_LINE: 0x02,
FIRST_ARC: 0x03
}; */
class Point {
constructor () {
this.x = 0
this.y = 0
this.z = null
this.m = null
}
}
const parsePoints = (buffer, count, isGeometryPoint) => {
// s2.1.5 + s2.1.6
// The key distinction for parsing is that a GEOGRAPHY POINT is ordered Lat (y) then Long (x),
// while a GEOMETRY POINT is ordered x then y.
// Further, there are additional range constraints on GEOGRAPHY POINT that are useful for testing that the coordinate order has not been flipped, such as that Lat must be in the range [-90, +90].
const points = []
if (count < 1) {
return points
}
if (isGeometryPoint) {
// GEOMETRY POINT (s2.1.6): x then y.
for (let i = 1; i <= count; i++) {
const point = new Point()
points.push(point)
point.x = buffer.readDoubleLE(buffer.position)
point.y = buffer.readDoubleLE(buffer.position + 8)
buffer.position += 16
}
} else {
// GEOGRAPHY POINT (s2.1.5): Lat (y) then Long (x).
for (let i = 1; i <= count; i++) {
const point = new Point()
points.push(point)
point.lat = buffer.readDoubleLE(buffer.position)
point.lng = buffer.readDoubleLE(buffer.position + 8)
// For backwards compatibility, preserve the coordinate inversion in x and y.
// A future breaking change likely eliminate x and y for geography points in favor of just the lat and lng fields, as they've proven marvelously confusing.
// See discussion at: https://github.com/tediousjs/node-mssql/pull/1282#discussion_r677769531
point.x = point.lat
point.y = point.lng
buffer.position += 16
}
}
return points
}
const parseZ = (buffer, points) => {
// s2.1.1 + s.2.1.2
if (points < 1) {
return
}
points.forEach(point => {
point.z = buffer.readDoubleLE(buffer.position)
buffer.position += 8
})
}
const parseM = (buffer, points) => {
// s2.1.1 + s.2.1.2
if (points < 1) {
return
}
points.forEach(point => {
point.m = buffer.readDoubleLE(buffer.position)
buffer.position += 8
})
}
const parseFigures = (buffer, count, properties) => {
// s2.1.3
const figures = []
if (count < 1) {
return figures
}
if (properties.P) {
figures.push({
attribute: 0x01,
pointOffset: 0
})
} else if (properties.L) {
figures.push({
attribute: 0x01,
pointOffset: 0
})
} else {
for (let i = 1; i <= count; i++) {
figures.push({
attribute: buffer.readUInt8(buffer.position),
pointOffset: buffer.readInt32LE(buffer.position + 1)
})
buffer.position += 5
}
}
return figures
}
const parseShapes = (buffer, count, properties) => {
// s2.1.4
const shapes = []
if (count < 1) {
return shapes
}
if (properties.P) {
shapes.push({
parentOffset: -1,
figureOffset: 0,
type: 0x01
})
} else if (properties.L) {
shapes.push({
parentOffset: -1,
figureOffset: 0,
type: 0x02
})
} else {
for (let i = 1; i <= count; i++) {
shapes.push({
parentOffset: buffer.readInt32LE(buffer.position),
figureOffset: buffer.readInt32LE(buffer.position + 4),
type: buffer.readUInt8(buffer.position + 8)
})
buffer.position += 9
}
}
return shapes
}
const parseSegments = (buffer, count) => {
// s2.1.7
const segments = []
if (count < 1) {
return segments
}
for (let i = 1; i <= count; i++) {
segments.push({ type: buffer.readUInt8(buffer.position) })
buffer.position++
}
return segments
}
const parseGeography = (buffer, isUsingGeometryPoints) => {
// s2.1.1 + s.2.1.2
const srid = buffer.readInt32LE(0)
if (srid === -1) {
return null
}
const value = {
srid,
version: buffer.readUInt8(4)
}
const flags = buffer.readUInt8(5)
buffer.position = 6
// console.log("srid", srid)
// console.log("version", version)
const properties = {
Z: (flags & (1 << 0)) > 0,
M: (flags & (1 << 1)) > 0,
V: (flags & (1 << 2)) > 0,
P: (flags & (1 << 3)) > 0,
L: (flags & (1 << 4)) > 0
}
if (value.version === 2) {
properties.H = (flags & (1 << 3)) > 0
}
// console.log("properties", properties);
let numberOfPoints
if (properties.P) {
numberOfPoints = 1
} else if (properties.L) {
numberOfPoints = 2
} else {
numberOfPoints = buffer.readUInt32LE(buffer.position)
buffer.position += 4
}
// console.log("numberOfPoints", numberOfPoints)
value.points = parsePoints(buffer, numberOfPoints, isUsingGeometryPoints)
if (properties.Z) {
parseZ(buffer, value.points)
}
if (properties.M) {
parseM(buffer, value.points)
}
// console.log("points", points)
let numberOfFigures
if (properties.P) {
numberOfFigures = 1
} else if (properties.L) {
numberOfFigures = 1
} else {
numberOfFigures = buffer.readUInt32LE(buffer.position)
buffer.position += 4
}
// console.log("numberOfFigures", numberOfFigures)
value.figures = parseFigures(buffer, numberOfFigures, properties)
// console.log("figures", figures)
let numberOfShapes
if (properties.P) {
numberOfShapes = 1
} else if (properties.L) {
numberOfShapes = 1
} else {
numberOfShapes = buffer.readUInt32LE(buffer.position)
buffer.position += 4
}
// console.log("numberOfShapes", numberOfShapes)
value.shapes = parseShapes(buffer, numberOfShapes, properties)
// console.log( "shapes", shapes)
if (value.version === 2 && buffer.position < buffer.length) {
const numberOfSegments = buffer.readUInt32LE(buffer.position)
buffer.position += 4
// console.log("numberOfSegments", numberOfSegments)
value.segments = parseSegments(buffer, numberOfSegments)
// console.log("segments", segments)
} else {
value.segments = []
}
return value
}
module.exports.PARSERS = {
geography (buffer) {
return parseGeography(buffer, /* isUsingGeometryPoints: */false)
},
geometry (buffer) {
return parseGeography(buffer, /* isUsingGeometryPoints: */true)
}
}