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96bba34 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 | import type { PathPoint } from "../api";
export type AlertKind = "hijack" | "goaround" | "holding" | "altitude" | "route" | "anomaly";
export interface AlertClassification {
kind: AlertKind;
label: string;
short: string;
reason: string;
critical: boolean;
}
const LEMD_LAT = 40.4936;
const LEMD_LON = -3.5668;
function distanceNm(lat: number, lon: number): number {
const R = 6371;
const dLat = ((lat - LEMD_LAT) * Math.PI) / 180;
const dLon = ((lon - LEMD_LON) * Math.PI) / 180;
const a = (LEMD_LAT * Math.PI) / 180;
const b = (lat * Math.PI) / 180;
const h = Math.sin(dLat / 2) ** 2 + Math.cos(a) * Math.cos(b) * Math.sin(dLon / 2) ** 2;
return (2 * R * Math.asin(Math.sqrt(h))) / 1.852;
}
function headingDeg(a: PathPoint, b: PathPoint): number {
const lat1 = (a.lat * Math.PI) / 180;
const lat2 = (b.lat * Math.PI) / 180;
const dLon = ((b.lon - a.lon) * Math.PI) / 180;
const y = Math.sin(dLon) * Math.cos(lat2);
const x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) * Math.cos(lat2) * Math.cos(dLon);
return ((Math.atan2(y, x) * 180) / Math.PI + 360) % 360;
}
function angularDiff(a: number, b: number): number {
let d = Math.abs(a - b) % 360;
if (d > 180) d = 360 - d;
return d;
}
export function classify(path: PathPoint[], currentStep: number): AlertClassification {
const window = path.slice(Math.max(0, currentStep - 5), currentStep + 1);
if (window.length < 2) {
return {
kind: "anomaly",
label: "UNCLASSIFIED ANOMALY",
short: "ANOM",
reason: "insufficient history",
critical: false,
};
}
const latVar = variance(window.map((p) => p.lat));
const lonVar = variance(window.map((p) => p.lon));
const altVar = variance(window.map((p) => p.alt));
const frozenSteps = window.length;
if (latVar < 1e-9 && lonVar < 1e-9 && altVar < 1e-2 && frozenSteps >= 3) {
return {
kind: "hijack",
label: "POSSIBLE HIJACK SIGNATURE",
short: "HIJK?",
reason: `transponder frozen ${frozenSteps} steps`,
critical: true,
};
}
const altsM = window.map((p) => p.alt);
const minAlt = Math.min(...altsM);
const lastAlt = altsM[altsM.length - 1];
const altRise = lastAlt - minAlt;
if (minAlt < 1500 && altRise > 250 && altsM[altsM.length - 1] > altsM[altsM.length - 2]) {
return {
kind: "goaround",
label: "GO-AROUND PATTERN",
short: "GA",
reason: `climb after low pass (${Math.round(minAlt)} m)`,
critical: false,
};
}
const headings: number[] = [];
for (let i = 1; i < window.length; i++) headings.push(headingDeg(window[i - 1], window[i]));
let totalTurn = 0;
for (let i = 1; i < headings.length; i++) totalTurn += angularDiff(headings[i], headings[i - 1]);
if (totalTurn > 180) {
return {
kind: "holding",
label: "HOLDING PATTERN",
short: "HOLD",
reason: `cumulative turn ${Math.round(totalTurn)}°`,
critical: false,
};
}
const current = path[currentStep];
const dist = distanceNm(current.lat, current.lon);
if (dist < 5 && current.alt > 3000) {
return {
kind: "altitude",
label: "ALTITUDE ANOMALY",
short: "ALT!",
reason: `${Math.round(current.alt)} m at ${dist.toFixed(1)} NM`,
critical: false,
};
}
if (dist > 20 && current.alt < 500) {
return {
kind: "altitude",
label: "ALTITUDE ANOMALY",
short: "ALT!",
reason: `${Math.round(current.alt)} m at ${dist.toFixed(1)} NM`,
critical: false,
};
}
if (headings.length >= 2) {
const meanHeading = circularMean(headings);
const lastHeading = headings[headings.length - 1];
if (angularDiff(meanHeading, lastHeading) > 30) {
return {
kind: "route",
label: "ROUTE DEVIATION",
short: "ROUTE",
reason: `heading drift ${Math.round(angularDiff(meanHeading, lastHeading))}°`,
critical: false,
};
}
}
return {
kind: "anomaly",
label: "UNCLASSIFIED ANOMALY",
short: "ANOM",
reason: "score above threshold, no clear signature",
critical: false,
};
}
function variance(values: number[]): number {
if (values.length === 0) return 0;
const mean = values.reduce((a, b) => a + b, 0) / values.length;
return values.reduce((acc, v) => acc + (v - mean) ** 2, 0) / values.length;
}
function circularMean(degrees: number[]): number {
let sx = 0;
let sy = 0;
for (const d of degrees) {
sx += Math.cos((d * Math.PI) / 180);
sy += Math.sin((d * Math.PI) / 180);
}
return ((Math.atan2(sy / degrees.length, sx / degrees.length) * 180) / Math.PI + 360) % 360;
}
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