import type { PieceSummary } from '../api';

export interface SplitPieces {
  defaults: PieceSummary[];
  customs: PieceSummary[];
}

/**
 * Split a flat list of PieceSummary into Default (built-in) and Custom sections.
 * Pieces with source === 'builtin' go to defaults; all others go to customs.
 */
export function splitPieces(pieces: PieceSummary[]): SplitPieces {
  const defaults: PieceSummary[] = [];
  const customs: PieceSummary[] = [];
  for (const p of pieces) {
    if (p.source === 'builtin') {
      defaults.push(p);
    } else {
      customs.push(p);
    }
  }
  return { defaults, customs };
}

/**
 * De-duplicate a flat list of PieceSummary by name, keeping the highest-priority
 * source for each name — mirroring the executor's resolution order:
 *   user-custom  >  global-custom  >  builtin
 *
 * Use this wherever a piece is SELECTED TO RUN (task creation, scheduled tasks,
 * continue-with-piece dialogs). The result matches what the executor will actually
 * run, so the user sees exactly one "chat" entry rather than two.
 *
 * Do NOT use this in the management/PiecesPage view — that view intentionally
 * shows both the builtin and any same-named custom side-by-side.
 */
export function resolvePieceOptions(pieces: PieceSummary[]): PieceSummary[] {
  const PRIORITY: Record<string, number> = {
    'user-custom': 0,
    'global-custom': 1,
    builtin: 2,
  };
  const seen = new Map<string, PieceSummary>();
  for (const p of pieces) {
    const existing = seen.get(p.name);
    const pPrio = PRIORITY[p.source ?? 'builtin'] ?? 2;
    if (!existing) {
      seen.set(p.name, p);
    } else {
      const existingPrio = PRIORITY[existing.source ?? 'builtin'] ?? 2;
      if (pPrio < existingPrio) {
        seen.set(p.name, p);
      }
    }
  }
  return Array.from(seen.values());
}