// lib/util/doors.mjs
// The `### Doors` list of a CHANGELOG release section: every delivery says
// whether it is a one-way door (cannot be walked back without a cost to users)
// or a two-way door (can). Moved here from scripts/release-check.mjs, which
// re-exports these names, because lib never imports scripts and the review
// evidence writer reads the door too. Door types are credited to
// mattpocock/skills@c55ee46 (idea only, no text copied).

export const DOOR_LINE_RE = /^- (one-way|two-way): \S/;

/**
 * The CHANGELOG section for `version`, heading line excluded, or null. Matches
 * `## v1.2.3 …`, `## [1.2.3] …` and `## 1.2.3 …` exactly: 1.1.0 is not 1.10.0
 * and not 1.1.0-pre.
 */
export function releaseSection(text, version) {
  if (typeof text !== 'string' || !version) return null;
  const lines = text.split('\n');
  const headingVersion = (line) => {
    const m = line.match(/^##\s+\[?v?([^\]\s(]+)\]?/);
    return m ? m[1] : null;
  };
  let start = -1;
  for (let i = 0; i < lines.length; i++) {
    if (/^##\s/.test(lines[i]) && headingVersion(lines[i]) === version) { start = i + 1; break; }
  }
  if (start === -1) return null;
  let end = lines.length;
  for (let i = start; i < lines.length; i++) {
    if (/^##\s/.test(lines[i])) { end = i; break; }
  }
  return lines.slice(start, end).join('\n');
}

/**
 * The `### Doors` list of a release section. Top-level `- ` lines must read
 * `- one-way: …` or `- two-way: …`; indented lines continue the entry above.
 * @returns {{ found: boolean, entries: Array<{door: string, text: string}>, bad: string[] }}
 */
export function parseDoors(section) {
  const lines = String(section ?? '').split('\n');
  const start = lines.findIndex((l) => /^###\s+Doors\s*$/.test(l));
  if (start === -1) return { found: false, entries: [], bad: [] };
  const entries = [];
  const bad = [];
  for (let i = start + 1; i < lines.length; i++) {
    const line = lines[i];
    if (/^#{2,3}\s/.test(line)) break;
    if (!line.startsWith('- ')) continue;
    const m = line.match(DOOR_LINE_RE);
    if (m) entries.push({ door: m[1], text: line.slice(m[0].length - 1).trim() });
    else bad.push(line);
  }
  return { found: true, entries, bad };
}