function createTodayWeekReschedule({
  week,
  api,
  getToday,
  adoptToday = () => {},
  operationId = () => globalThis.crypto?.randomUUID?.() || String(Date.now()),
} = {}) {
  let current = null;

  async function open(identity) {
    const today = await api('api/v1/today');
    if (!identity || !today?.ids?.includes(identity)) {
      throw new Error('The active Today item changed. Reopen rescheduling.');
    }
    const loaded = await week.load();
    if (loaded?.offline_snapshot || loaded?.sync_pending) {
      throw new Error('Reconnect before rescheduling Today into Week Ahead.');
    }
    const estimate = Number(today.estimates?.[identity]);
    const estimateMinutes = Number.isFinite(estimate) && estimate > 0 ? estimate : null;
    const days = week.review().days.map(day => {
      const ids = (day.ids || []).filter(id => id !== identity);
      const planned = Number(day.planned_minutes) || 0;
      const existing = Number(day.estimates?.[identity]) || 0;
      return {
        ...day,
        ids,
        planned_minutes: Math.max(0, planned - existing),
        load: `${Math.max(0, planned - existing)} / ${Number(day.capacity_minutes) || 0} min`,
        eligible: ids.length < 5,
      };
    });
    current = {
      identity,
      today_revision: today.revision,
      week_revision: loaded.revision,
      operation_id: operationId(),
      estimate_minutes: estimateMinutes,
      days,
    };
    return {...current, days:days.map(day => ({...day, ids:[...day.ids]}))};
  }

  async function confirm(planDate, estimateMinutes, {allowOverload = false} = {}) {
    if (!current) throw new Error('Open rescheduling before choosing a day.');
    const day = current.days.find(value => value.plan_date === planDate);
    if (!day) throw new Error('Choose one of the next seven days.');
    const estimate = Number(estimateMinutes);
    if (!Number.isFinite(estimate) || estimate < 5 || estimate > 1440) {
      throw new Error('Estimate must be between 5 and 1440 minutes.');
    }
    if (!day.eligible) throw new Error('That Week Ahead day already has five items.');
    const capacity = Number(day.capacity_minutes) || 0;
    if (capacity && day.planned_minutes + estimate > capacity && !allowOverload) {
      throw new Error("That move exceeds the day's capacity. Confirm overload before rescheduling.");
    }
    const result = await api('api/v1/week/reschedule', {
      method:'POST',
      headers:{'Content-Type':'application/json'},
      body:JSON.stringify({
        operation_id:current.operation_id,
        identity:current.identity,
        estimate_minutes:estimate,
        plan_date:planDate,
        today_revision:current.today_revision,
        week_revision:current.week_revision,
        allow_over_capacity:allowOverload,
      }),
    });
    adoptToday(result.today);
    week.adopt(result.week);
    current = null;
    return result;
  }

  function cancel() { current = null; }
  return {open, confirm, cancel, state:() => current};
}

function mountTodayWeekReschedule({
  qs, document=globalThis.document, week, api, getToday, adoptToday, currentTarget, closeActions,
  refresh, warm, continueToday, announce, schedule=callback=>requestAnimationFrame(callback),
}={}) {
  const dialog=qs('#today-week-reschedule'),daysRoot=qs('#today-week-reschedule-days');
  const estimate=qs('#today-week-reschedule-estimate'),status=qs('#today-week-reschedule-status');
  const confirm=qs('#confirm-today-week-reschedule'),launcher=qs('[data-work-session-reschedule-week]');
  let selectedDate=null,allowOverload=false;
  const controller=createTodayWeekReschedule({week,api,getToday,adoptToday});
  function close() {
    controller.cancel();selectedDate=null;allowOverload=false;
    if(dialog.open)dialog.close();schedule(()=>{
      qs('[data-mobile-today-more]').click();launcher.focus();
    });
  }
  function render(opened) {
    daysRoot.replaceChildren(...opened.days.map(day=>{
      const button=document.createElement('button');
      button.type='button';button.dataset.planDate=day.plan_date;button.setAttribute('role','radio');
      button.setAttribute('aria-checked','false');button.disabled=!day.eligible;
      const label=document.createElement('strong');label.textContent=day.label;
      const load=document.createElement('span');load.className='small';
      load.textContent=day.eligible?day.load:'5 items · full';button.append(label,load);
      button.addEventListener('click',()=>{
        selectedDate=day.plan_date;allowOverload=false;
        daysRoot.querySelectorAll('button').forEach(choice=>choice.setAttribute(
          'aria-checked',String(choice===button)
        ));
        status.textContent='';confirm.disabled=false;confirm.textContent='Move to Week Ahead & continue';
      });
      return button;
    }));
  }
  launcher.addEventListener('click',async()=>{
    const target=currentTarget();
    if(!target){announce('Start or resume a checkpointed Today item before rescheduling.');return;}
    closeActions();status.textContent='Loading Week Ahead…';confirm.disabled=true;dialog.showModal();
    try{
      const opened=await controller.open(target.identity);render(opened);
      estimate.value=opened.estimate_minutes||'';
      status.textContent=opened.estimate_minutes?'Choose a future day.':'Add an estimate, then choose a future day.';
      schedule(()=>daysRoot.querySelector('button:not(:disabled)')?.focus());
    }catch(error){status.textContent=error.message;}
  });
  qs('#cancel-today-week-reschedule').addEventListener('click',close);
  dialog.addEventListener('cancel',event=>{event.preventDefault();close();});
  confirm.addEventListener('click',async()=>{
    if(!selectedDate)return;
    confirm.disabled=true;status.textContent='Moving Today into Week Ahead…';
    try{
      await controller.confirm(selectedDate,Number(estimate.value),{allowOverload});
      await refresh();warm();dialog.close();announce('Moved to Week Ahead. Continuing Today.');
      await continueToday();
    }catch(error){
      const overload=error.message.includes('Confirm overload');allowOverload=overload;
      status.textContent=error.message;
      confirm.textContent=overload?'Confirm overload & continue':'Move to Week Ahead & continue';
      confirm.disabled=false;
    }
  });
  return {controller,close};
}

if (typeof module !== 'undefined' && module.exports) {
  module.exports = createTodayWeekReschedule;
  module.exports.mount = mountTodayWeekReschedule;
}