import { z } from 'zod';
import { NavigationRoute, Waypoint } from '../types/enc.js';
const CalculateRouteSchema = z.object({
waypoints: z
.array(
z.object({
lat: z.number(),
lon: z.number(),
name: z.string().optional(),
})
)
.min(2),
avoidAreas: z
.array(
z.object({
minLat: z.number(),
maxLat: z.number(),
minLon: z.number(),
maxLon: z.number(),
})
)
.optional(),
});
export async function calculateRouteHandler(args: unknown): Promise<{
content: Array<{ type: string; text: string }>;
}> {
const params = CalculateRouteSchema.parse(args);
// TODO: Implement actual route calculation
// This would use navigation algorithms considering:
// - Chart depths
// - Navigation hazards
// - Traffic separation schemes
// - Avoid areas
// Simple great circle distance calculation for mock
const calculateDistance = (wp1: Waypoint, wp2: Waypoint): number => {
const R = 3440.1; // Earth radius in nautical miles
const dLat = ((wp2.lat - wp1.lat) * Math.PI) / 180;
const dLon = ((wp2.lon - wp1.lon) * Math.PI) / 180;
const a =
Math.sin(dLat / 2) * Math.sin(dLat / 2) +
Math.cos((wp1.lat * Math.PI) / 180) *
Math.cos((wp2.lat * Math.PI) / 180) *
Math.sin(dLon / 2) *
Math.sin(dLon / 2);
const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
return R * c;
};
const calculateBearing = (wp1: Waypoint, wp2: Waypoint): number => {
const dLon = ((wp2.lon - wp1.lon) * Math.PI) / 180;
const lat1 = (wp1.lat * Math.PI) / 180;
const lat2 = (wp2.lat * 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);
const bearing = (Math.atan2(y, x) * 180) / Math.PI;
return (bearing + 360) % 360;
};
// Process waypoints
const processedWaypoints: Waypoint[] = [];
let totalDistance = 0;
for (let i = 0; i < params.waypoints.length; i++) {
const wp: Waypoint = { ...params.waypoints[i] };
if (i < params.waypoints.length - 1) {
const nextWp = params.waypoints[i + 1];
wp.bearing = calculateBearing(wp, nextWp);
wp.distance = calculateDistance(wp, nextWp);
totalDistance += wp.distance || 0;
}
processedWaypoints.push(wp);
}
const route: NavigationRoute = {
waypoints: processedWaypoints,
distance: totalDistance,
estimatedTime: totalDistance / 10, // Assuming 10 knots average speed
};
return {
content: [
{
type: 'text',
text: JSON.stringify(
{
route,
totalDistance: `${totalDistance.toFixed(1)} NM`,
estimatedTime: `${route.estimatedTime.toFixed(1)} hours`,
avoidAreasConsidered: params.avoidAreas?.length ?? 0,
},
null,
2
),
},
],
};
}
