Function setupSignatureHelp

packages/lsp/src/server/signatureHelp.ts:24–51

(connection: Connection, documents: TextDocuments<AlphaTexTextDocument>)

import { binaryNodeSearch, parameterToSyntax } from '@coderline/alphatab-language-server/server/utils';

export function setupSignatureHelp(connection: Connection, documents: TextDocuments<AlphaTexTextDocument>) {
    connection.onSignatureHelp(params => {
        const document = documents.get(params.textDocument.uri);
        if (!document?.ast) {
            return null;
        }

        const offset = document.offsetAt(params.position);

        // lookup bar at location
        const bar = binaryNodeSearch(document.ast.bars, offset);
        if (!bar) {
            return null;
        }

        const metaData = binaryNodeSearch(bar.metaData, offset);
        if (metaData) {
            return createMetaDataSignatureHelp(metaData, offset);
        }

        const beat = binaryNodeSearch(bar.beats, offset);
        if (beat) {
            return createBeatSignatureHelp(beat, offset);
        }

        return null;
    });
}

function createMetaDataSignatureHelp(
    metaData: alphaTab.importer.alphaTex.AlphaTexMetaDataNode,