// owasp-map.mjs — Scanner-prefix to OWASP LLM Top 10 map, built from vendored commons.
//
// v8 Phase 5 step 4, second consumer swap. `OWASP_MAP` was a hardcoded
// constant in severity.mjs; it is now built once, here, from
// `mapping/owasp-map.json` in the vendored llm-security-commons subtree.
// Verified byte-equal to the pre-swap constant before the swap: the same 16
// prefixes, in the same order, with the same code arrays.
//
// commons publishes four parallel maps in that one artifact. This module
// builds ONE of them, and the omission is a measurement, not an oversight:
//
//   - `taxonomies.llm` (OWASP_MAP) has a production consumer —
//     `owaspCategorize()` reads it as the per-scanner fallback, and that
//     function reaches real report output via output.mjs's `owasp_breakdown`.
//   - `taxonomies.agentic` / `.skills` / `.mcp` (OWASP_AGENTIC_MAP,
//     OWASP_SKILLS_MAP, OWASP_MCP_MAP) have none. Measured tree-wide at
//     b1ba1fb: every reference is a test or a golden artifact. They stay
//     source literals in severity.mjs — loading data no runtime consumes
//     would move it into the load path for nothing, the same call already
//     made for `cyrillic_confusables` in the first swap.
//
// Graceful-empty, matching commons-loader.mjs's contract: severity.mjs is on
// the import path of output.mjs and of every orchestrated scanner, so a
// module-load throw here would abort a scan rather than degrade it. An empty
// map degrades `owaspCategorize` to 'Unmapped' for findings that carry no
// explicit `owasp` field — visible in a report, not fatal. The cost of that
// choice is that a lost commons is silent at runtime, so the loud half lives
// in `tests/lib/owasp-map.test.mjs`, which asserts the exact prefix count and
// named entries through the real default root.
//
// Zero external dependencies — Node.js builtins only.

import { loadArtifact } from './commons-loader.mjs';

/**
 * Build the OWASP LLM prefix map from a commons root.
 *
 * Entries are validated rather than trusted: commons is vendored data, and a
 * value that is not an array of strings would be spread straight into
 * `owaspCategorize`'s category list. A malformed entry is dropped, not
 * published.
 *
 * @param {object} [opts]
 * @param {string} [opts.commonsRoot] - explicit commons root (tests, dev checkout).
 * @returns {Readonly<Record<string, readonly string[]>>} prefix -> OWASP LLM codes
 */
export function buildOwaspMap(opts = {}) {
  const artifact = loadArtifact('mapping/owasp-map', { fallback: {}, commonsRoot: opts.commonsRoot });
  const source = artifact?.taxonomies?.llm?.map;

  const map = {};
  if (source !== null && typeof source === 'object') {
    for (const [prefix, codes] of Object.entries(source)) {
      if (!Array.isArray(codes)) continue;
      if (!codes.every((code) => typeof code === 'string')) continue;
      // Array order is semantic — it reaches report output in this order — so
      // the codes are copied, never sorted.
      map[prefix] = Object.freeze([...codes]);
    }
  }
  return Object.freeze(map);
}

/**
 * Scanner prefix to OWASP LLM Top 10 category mapping.
 *
 * An empty array is data, not a gap: it records that the seed implementation
 * deliberately maps that prefix to nothing in this taxonomy.
 */
export const OWASP_MAP = buildOwaspMap();