import type { ProjectRecord } from '../index'; import type { EmbeddingProvider, ProjectRepository } from '../providers/types';

export type SemanticRanker = { /**

• Compute similarity scores for the provided projects given the natural-language query. */ scoreProjects(projects: ProjectRecord[], query: string): Promise<Map<string, number>>; };

type EmbeddingSemanticRankerOptions = { embeddingProvider: EmbeddingProvider; projectRepository: Pick<ProjectRepository, 'getEmbedding'>; scoreScale?: number; };

function normalizeQuery(query: string): string { return typeof query === 'string' ? query.trim() : ''; }

export function cosineSimilarity(a: number[] | undefined, b: number[] | undefined): number { if (!a?.length || !b?.length || a.length !== b.length) { return 0; }

let dot = 0; let magA = 0; let magB = 0; for (let i = 0; i < a.length; i += 1) { const valA = a[i]!; const valB = b[i]!; dot += valA * valB; magA += valA * valA; magB += valB * valB; }

if (!magA || !magB) { return 0; }

return dot / (Math.sqrt(magA) * Math.sqrt(magB)); }

export function createEmbeddingSemanticRanker(options: EmbeddingSemanticRankerOptions): SemanticRanker { const { embeddingProvider, projectRepository, scoreScale = 12 } = options;

return { async scoreProjects(projects, query) { if (!projects.length) { return new Map(); }

  const normalized = normalizeQuery(query);
  if (!normalized) {
    return new Map();
  }

  const embeddings = await embeddingProvider.embedTexts([normalized]);
  const queryEmbedding = embeddings[0];
  if (!queryEmbedding?.length) {
    return new Map();
  }

  const scores = new Map<string, number>();
  for (const project of projects) {
    const projectEmbedding = projectRepository.getEmbedding
      ? await projectRepository.getEmbedding(project)
      : undefined;
    if (!projectEmbedding?.length) {
      continue;
    }
    const similarity = cosineSimilarity(queryEmbedding, projectEmbedding);
    if (similarity > 0) {
      scores.set(project.id, similarity * scoreScale);
    }
  }

  return scores;
},

}; }