// services/callReport/collapseDisplayCalls.js
// Collapse repetitive AA-only bursts for readable /callreport output.

import { formatLocalTime } from './formatCallLine.js';

function callerKey(call) {
  return [
    call.callingLineId || call.leftParty?.lineId || '',
    call.callingNumber || call.leftParty?.number || '',
    call.aaKeyPress || '',
  ].join('|');
}

/**
 * Collapse 3+ AA-only calls from the same caller into a single summary row.
 * @param {object[]} calls
 * @param {{ timeZone?: string, minBurst?: number }} opts
 * @returns {Array<object|{ kind: 'burst', calls: object[], summary: string }>}
 */
export function collapseAaBursts(calls, opts = {}) {
  const minBurst = opts.minBurst ?? 3;
  const timeZone = opts.timeZone;
  const out = [];
  let i = 0;

  while (i < (calls || []).length) {
    const call = calls[i];
    const key = callerKey(call);
    let j = i + 1;
    while (j < calls.length && callerKey(calls[j]) === key) j += 1;
    const group = calls.slice(i, j);

    if (group.length >= minBurst) {
      const first = group[0];
      const last = group[group.length - 1];
      const left = first.callingLineId && String(first.callingLineId).toUpperCase() !== 'NA'
        ? `${first.callingLineId} (${first.callingNumber || ''})`
        : (first.callingNumber || '?');
      const main = first.storeMainNumber || first.calledNumber || '?';
      const start = formatLocalTime(first.start, timeZone);
      const end = formatLocalTime(last.start, timeZone);
      const keyLabel = first.aaKeyPress ? ` (AA key ${first.aaKeyPress})` : '';
      out.push({
        kind: 'burst',
        calls: group,
        summary:
          `⚠️ ${start}–${end}: ${left} → ${main}${keyLabel} — ` +
          `${group.length} calls stopped at auto-attendant`,
      });
    } else {
      out.push(...group);
    }
    i = j;
  }

  return out;
}