import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { z } from 'zod';
import { readFile } from 'node:fs/promises';
import { parseDefinitions } from './parse-utils.js';
export function registerDocumentSymbolsTool(server: McpServer): void {
server.registerTool(
'gerbil_document_symbols',
{
title: 'Document Symbols with Positions',
description:
'List all definitions in a Gerbil source file with name, kind, and line number. ' +
'Returns structs, classes, procedures, macros, methods, constants, imports, and exports.',
inputSchema: {
file_path: z
.string()
.describe(
'Absolute path to a Gerbil source file (.ss or .scm)',
),
},
},
async ({ file_path }) => {
let content: string;
try {
content = await readFile(file_path, 'utf-8');
} catch (err) {
const msg =
err instanceof Error ? err.message : 'Unknown error';
return {
content: [
{ type: 'text' as const, text: `Failed to read file: ${msg}` },
],
isError: true,
};
}
if (!content.trim()) {
return {
content: [{ type: 'text' as const, text: 'File is empty.' }],
};
}
const analysis = parseDefinitions(content);
const sections: string[] = [`File: ${file_path}`, ''];
if (analysis.imports.length > 0) {
sections.push(`Imports (${analysis.imports.length}):`);
for (const imp of analysis.imports) {
const display =
imp.raw.length > 120 ? imp.raw.slice(0, 120) + '...' : imp.raw;
sections.push(` L${imp.line}: ${display}`);
}
sections.push('');
}
if (analysis.exports.length > 0) {
sections.push(`Exports (${analysis.exports.length}):`);
for (const exp of analysis.exports) {
const display =
exp.raw.length > 120 ? exp.raw.slice(0, 120) + '...' : exp.raw;
sections.push(` L${exp.line}: ${display}`);
}
sections.push('');
}
if (analysis.definitions.length > 0) {
sections.push(`Definitions (${analysis.definitions.length}):`);
for (const def of analysis.definitions) {
sections.push(` L${def.line}: ${def.name} (${def.kind})`);
}
}
if (
analysis.definitions.length === 0 &&
analysis.imports.length === 0 &&
analysis.exports.length === 0
) {
return {
content: [
{
type: 'text' as const,
text: `No definitions found in ${file_path}.`,
},
],
};
}
return {
content: [{ type: 'text' as const, text: sections.join('\n') }],
};
},
);
}
