Enhanced Knowledge Graph Memory Server

/** * Search Suggestions * * Provides "did you mean?" suggestions using Levenshtein distance. * * @module search/SearchSuggestions */ import type { GraphStorage } from '../core/GraphStorage.js'; import { levenshteinDistance } from '../utils/levenshtein.js'; /** * Internal suggestion with similarity score. */ interface Suggestion { text: string; similarity: number; } /** * Generates search suggestions based on entity names and types. */ export class SearchSuggestions { constructor(private storage: GraphStorage) {} /** * Get "did you mean?" suggestions for a query. * * Returns similar entity names and types that might be what the user intended. * Excludes exact matches (similarity < 1.0) and very dissimilar strings (similarity > 0.5). * * @param query - The search query * @param maxSuggestions - Maximum number of suggestions to return (default 5) * @returns Array of suggested entity/type names sorted by similarity */ async getSearchSuggestions(query: string, maxSuggestions: number = 5): Promise<string[]> { const graph = await this.storage.loadGraph(); const queryLower = query.toLowerCase(); const suggestions: Suggestion[] = []; // Check entity names for (const entity of graph.entities) { const distance = levenshteinDistance(queryLower, entity.name.toLowerCase()); const maxLength = Math.max(queryLower.length, entity.name.length); const similarity = 1 - distance / maxLength; if (similarity > 0.5 && similarity < 1.0) { // Not exact match but similar suggestions.push({ text: entity.name, similarity }); } } // Check entity types const uniqueTypes = [...new Set(graph.entities.map(e => e.entityType))]; for (const type of uniqueTypes) { const distance = levenshteinDistance(queryLower, type.toLowerCase()); const maxLength = Math.max(queryLower.length, type.length); const similarity = 1 - distance / maxLength; if (similarity > 0.5 && similarity < 1.0) { suggestions.push({ text: type, similarity }); } } // Sort by similarity and return top suggestions return suggestions .sort((a, b) => b.similarity - a.similarity) .slice(0, maxSuggestions) .map(s => s.text); } }