const DAYS = ['sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat'];
const DAY_LABELS = {
  sun: 'Domingo',
  mon: 'Lunes',
  tue: 'Martes',
  wed: 'Miércoles',
  thu: 'Jueves',
  fri: 'Viernes',
  sat: 'Sábado',
};

export const DAY_KEYS = DAYS;
export const DAY_LABEL = DAY_LABELS;

function parseHM(str) {
  const [h, m] = str.split(':').map(Number);
  if (!Number.isFinite(h) || !Number.isFinite(m)) return null;
  return h * 60 + m;
}

function parseHours(raw) {
  if (!raw) return null;
  try {
    return typeof raw === 'string' ? JSON.parse(raw) : raw;
  } catch {
    return null;
  }
}

function findNextOpenInfo(hours, now) {
  for (let offset = 1; offset <= 7; offset++) {
    const day = DAYS[(now.getDay() + offset) % 7];
    const range = hours[day];
    if (Array.isArray(range) && range.length === 2) {
      return { day, time: range[0], offset };
    }
  }
  return null;
}

export function getOpenStatus(rawHours, now = new Date()) {
  const hours = parseHours(rawHours);
  if (!hours) return { status: 'unknown', label: 'Sin horario', labelKey: 'pharmacy.noHours', labelParams: {} };

  if (isAlwaysOpen(hours)) {
    return { status: 'open', label: 'Abierto 24h', labelKey: 'pharmacy.alwaysOpen', labelParams: {} };
  }

  const day = DAYS[now.getDay()];
  const range = hours[day];

  if (!Array.isArray(range) || range.length !== 2) {
    const next = findNextOpenInfo(hours, now);
    if (!next) {
      return { status: 'closed', label: 'Cerrado', labelKey: 'pharmacy.closedAllDay', labelParams: {} };
    }
    if (next.offset === 1) {
      return { status: 'closed', label: `Cerrado · Abre mañana a las ${next.time}`, labelKey: 'pharmacy.opensTomorrow', labelParams: { time: next.time } };
    }
    return { status: 'closed', label: `Cerrado · Abre el ${DAY_LABELS[next.day]} a las ${next.time}`, labelKey: 'pharmacy.opensDay', labelParams: { day: DAY_LABELS[next.day], time: next.time } };
  }

  const openMins = parseHM(range[0]);
  const closeMins = parseHM(range[1]);
  if (openMins == null || closeMins == null) return null;

  const nowMins = now.getHours() * 60 + now.getMinutes();

  if (nowMins < openMins) {
    return { status: 'closed', label: `Cerrado · Abre a las ${range[0]}`, labelKey: 'pharmacy.opensAt', labelParams: { time: range[0] } };
  }
  if (nowMins >= closeMins) {
    const next = findNextOpenInfo(hours, now);
    if (!next) {
      return { status: 'closed', label: 'Cerrado', labelKey: 'pharmacy.closedAllDay', labelParams: {} };
    }
    if (next.offset === 1) {
      return { status: 'closed', label: `Cerrado · Abre mañana a las ${next.time}`, labelKey: 'pharmacy.opensTomorrow', labelParams: { time: next.time } };
    }
    return { status: 'closed', label: `Cerrado · Abre el ${DAY_LABELS[next.day]} a las ${next.time}`, labelKey: 'pharmacy.opensDay', labelParams: { day: DAY_LABELS[next.day], time: next.time } };
  }
  return { status: 'open', label: `Abierto · Cierra a las ${range[1]}`, labelKey: 'pharmacy.openNow', labelParams: { time: range[1] } };
}

export function emptyHours() {
  return { sun: null, mon: null, tue: null, wed: null, thu: null, fri: null, sat: null };
}

export function emptyHoursDraft() {
  const draft = {};
  for (const day of DAYS) {
    draft[day] = { open: '09:00', close: '21:00', closed: true };
  }
  return draft;
}

export function hoursToDraft(raw) {
  let parsed = null;
  if (raw) {
    try { parsed = typeof raw === 'string' ? JSON.parse(raw) : raw; }
    catch { parsed = null; }
  }
  const draft = {};
  for (const day of DAYS) {
    const v = parsed && parsed[day];
    if (Array.isArray(v) && v.length === 2) {
      draft[day] = { open: v[0], close: v[1], closed: false };
    } else {
      draft[day] = { open: '09:00', close: '21:00', closed: true };
    }
  }
  return draft;
}

export function draftToHours(draft) {
  const out = {};
  let hasAny = false;
  for (const day of DAYS) {
    const d = draft[day];
    if (d && !d.closed && d.open && d.close) {
      out[day] = [d.open, d.close];
      hasAny = true;
    } else {
      out[day] = null;
    }
  }
  return hasAny ? out : null;
}

export function isAlwaysOpen(rawHours) {
  const h = parseHours(rawHours);
  if (!h) return false;
  for (const d of DAYS) {
    const r = h[d];
    if (!Array.isArray(r) || r.length !== 2) return false;
    if (r[0] !== '00:00' || r[1] !== '24:00') return false;
  }
  return true;
}

export function makeAlwaysOpenDraft() {
  const draft = {};
  for (const day of DAYS) {
    draft[day] = { open: '00:00', close: '24:00', closed: false };
  }
  return draft;
}