LODA MCP Server

/**
 * @file relevance_scorer.js
 * @description Score section relevance to query
 * @atomic ATOM (controlled computation, no state)
 * @component LODA-MCP-COMP-05
 */

/**
 * Calculate relevance score for section against query
 * @implements LODA-MCP-DT-05 (Query + sections → Relevance scores)
 * @param {Object} section - Section object with content
 * @param {string} query - Search query
 * @returns {number} Score 0-1
 */
function calculateRelevance(section, query) {
  if (!query || !section || !section.content) return 0;

  const content = section.content.toLowerCase();
  const header = (section.header || '').toLowerCase();
  const queryTerms = query.toLowerCase().split(/\s+/).filter(t => t.length > 0);

  if (queryTerms.length === 0) return 0;

  let score = 0;
  let matchedTerms = 0;

  for (const term of queryTerms) {
    if (content.includes(term)) {
      matchedTerms++;
      // Bonus for header match
      if (header.includes(term)) {
        score += 0.2;
      }
    }
  }

  // Base score from term coverage
  score += (matchedTerms / queryTerms.length) * 0.8;

  return Math.min(1, score);
}

module.exports = { calculateRelevance };