import { McpServer, ResourceTemplate } from "@modelcontextprotocol/sdk/server/mcp.js";
import { ValhallaClient } from "../clients/valhalla.js";
import { logger } from "../utils/logger.js";
export function setupTileResource(server: McpServer, valhallaClient: ValhallaClient): void {
server.registerResource(
"tile",
new ResourceTemplate("tile://{z}/{x}/{y}", { list: undefined }),
{
title: "Valhalla Vector Tile",
description: "Provides Valhalla vector tiles in Mapbox protobuf format for client-side rendering",
mimeType: "application/x-protobuf"
},
async (uri: any, params: any) => {
try {
const { z, x, y } = params;
// Validate tile coordinates
const zoom = parseInt(z as string);
const tileX = parseInt(x as string);
const tileY = parseInt(y as string);
if (isNaN(zoom) || isNaN(tileX) || isNaN(tileY)) {
throw new Error("Invalid tile coordinates");
}
if (zoom < 0 || zoom > 18) {
throw new Error("Zoom level must be between 0 and 18");
}
const maxTileIndex = Math.pow(2, zoom) - 1;
if (tileX < 0 || tileX > maxTileIndex || tileY < 0 || tileY > maxTileIndex) {
throw new Error(`Tile coordinates out of range for zoom level ${zoom}`);
}
logger.info(`Fetching tile ${zoom}/${tileX}/${tileY}`);
// Fetch tile data from Valhalla
const tileData = await valhallaClient.tile(zoom, tileX, tileY);
// Convert Buffer to base64 for transport
const base64Data = tileData.toString('base64');
return {
contents: [
{
uri: uri.href,
mimeType: "application/x-protobuf",
blob: base64Data
}
]
};
} catch (error) {
logger.error(`Failed to fetch tile ${params.z}/${params.x}/${params.y}:`, error);
// Return error as JSON
const errorData = {
error: "Failed to fetch tile",
message: error instanceof Error ? error.message : "Unknown error",
type: "tile_error",
tile: {
z: params.z,
x: params.x,
y: params.y
}
};
return {
contents: [
{
uri: uri.href,
mimeType: "application/json",
text: JSON.stringify(errorData, null, 2)
}
]
};
}
}
);
logger.info("Tile resource registered");
}
