// Orchestrates the trip page: header + calendar, then map + summary.
// Owns the shared trip context passed to the calendar, map, summary and
// day-editor sub-views: { state, navigate, tripId, trip, route, refreshTrip,
// openDay }. After any mutation, refreshTrip() re-fetches the trip and its
// derived /route data so all three panels stay in sync.
import { api } from '../api.js';
import { el, clear, mount, loading, errorBox, toast } from '../dom.js';
import { formatRange, daysBetweenInclusive, pluralize, groupCode } from '../format.js';
import { renderCalendar } from './calendar.js';
import { renderMap } from './map.js';
import { renderSummary } from './summary.js';
import { renderCosts } from './costs.js';
import { renderExpenses } from './expenses.js';
import { renderChecklist } from './checklist.js';
import { renderCountdown } from './flipclock.js';
import { openDayEditor } from './dayEditor.js';

export function renderTripDetail(container, ctx, id) {
  const tctx = {
    ...ctx,
    tripId: id,
    trip: null,
    route: null,
    costs: null,
    _onModalRefresh: null,
  };

  // The mounted Costs section node, so refreshCosts() can swap it in place
  // without redrawing the whole page (self-fetching cards like Expenses
  // trigger this instead of tctx.refreshTrip()).
  let costsSection = null;

  mount(container, loading('Loading trip…'));
  init();

  async function load() {
    const [trip, route, costs] = await Promise.all([
      api.trips.get(id),
      api.trips.route(id),
      api.trips.costs(id),
    ]);
    tctx.trip = trip;
    tctx.route = route;
    tctx.costs = costs;
  }

  tctx.refreshTrip = async () => {
    try {
      await load();
      draw();
      if (typeof tctx._onModalRefresh === 'function') tctx._onModalRefresh();
    } catch (err) {
      toast(err.message);
    }
  };

  // Lighter-weight than refreshTrip(): re-fetches only /costs and swaps the
  // Costs section in place, so a self-fetching card (Expenses) can keep the
  // settle-up numbers current without re-fetching the trip/route or
  // re-mounting every other panel.
  tctx.refreshCosts = async () => {
    try {
      tctx.costs = await api.trips.costs(id);
      if (costsSection && costsSection.isConnected) {
        const next = renderCosts(tctx);
        costsSection.replaceWith(next);
        costsSection = next;
      }
    } catch (err) {
      toast(err.message);
    }
  };

  tctx.openDay = (date) => openDayEditor(tctx, date);

  async function init() {
    try {
      await load();
      draw();
    } catch (err) {
      clear(container);
      if (err.status === 404) {
        toast('Trip not found (or you are not a member).');
        ctx.navigate('#/trips');
        return;
      }
      mount(container, errorBox(err.message, init));
    }
  }

  function draw() {
    const page = el('div', { class: 'page' });
    page.appendChild(renderHeader());
    page.appendChild(renderCountdown(tctx));
    page.appendChild(renderCalendar(tctx));
    costsSection = renderCosts(tctx);
    page.appendChild(
      el(
        'div',
        { class: 'detail-grid' },
        renderMap(tctx),
        el(
          'div',
          { class: 'detail-side' },
          renderSummary(tctx),
          costsSection,
          renderExpenses(tctx),
          renderChecklist(tctx),
        ),
      ),
    );
    mount(container, page);
  }

  function renderHeader() {
    const { trip, members } = tctx.trip;
    const isOwner = trip.owner_id === tctx.state.user.id;
    const dayCount = daysBetweenInclusive(trip.start_date, trip.end_date);

    const header = el('div', { class: 'trip-header card' });

    const titleRow = el(
      'div',
      { class: 'trip-header-top' },
      el(
        'div',
        {},
        el(
          'a',
          { class: 'back-link', href: '#/trips' },
          '← All trips',
        ),
        el('h1', { class: 'trip-title' }, trip.name),
        el(
          'p',
          { class: 'trip-subtitle muted' },
          '📅 ', formatRange(trip.start_date, trip.end_date),
          '  ·  ', pluralize(dayCount, 'day', 'days'),
          '  ·  ', el('span', { class: 'currency-tag' }, trip.currency || 'USD'),
        ),
      ),
      el(
        'div',
        { class: 'trip-header-actions' },
        el('button', { class: 'btn btn-ghost', onClick: () => toggleEdit(header) }, '✎ Edit'),
        isOwner
          ? el('button', { class: 'btn btn-danger-ghost', onClick: onDelete }, 'Delete')
          : null,
      ),
    );

    const membersRow = el(
      'div',
      { class: 'members-row' },
      el('span', { class: 'members-label' }, 'Members:'),
      ...members.map((m) =>
        el(
          'span',
          { class: `member-chip${m.role === 'owner' ? ' member-owner' : ''}` },
          el('span', { class: 'member-avatar' }, (m.display_name || '?').charAt(0).toUpperCase()),
          m.display_name,
          isOwner && m.role !== 'owner'
            ? el('button', {
                class: 'member-remove',
                title: `Remove ${m.display_name}`,
                onClick: () => onRemoveMember(m),
              }, '×')
            : null,
        ),
      ),
    );

    header.appendChild(titleRow);
    header.appendChild(joinCodeRow(trip, isOwner));
    header.appendChild(membersRow);
    return header;
  }

  // Share code for inviting others — display only, not a credential.
  function joinCodeRow(trip, isOwner) {
    const grouped = groupCode(trip.join_code, 4);
    const copyBtn = el('button', { class: 'btn btn-sm', type: 'button', title: 'Copy join code' }, '📋 Copy');
    copyBtn.addEventListener('click', async () => {
      try {
        await navigator.clipboard.writeText(grouped);
        toast('Join code copied', 'success');
      } catch {
        toast('Copy failed — select and copy it manually');
      }
    });

    async function onRegenerate() {
      if (!window.confirm('Regenerate the join code? The old code will stop working immediately.')) return;
      try {
        await api.trips.regenerateJoinCode(tctx.tripId);
        toast('Join code regenerated', 'success');
        await tctx.refreshTrip();
      } catch (err) {
        toast(err.message);
      }
    }

    return el(
      'div',
      { class: 'joincode-row' },
      el('span', { class: 'members-label' }, 'Join code:'),
      el('span', { class: 'joincode-chip' }, grouped),
      copyBtn,
      isOwner
        ? el('button', { class: 'btn btn-sm btn-ghost', type: 'button', onClick: onRegenerate }, '↻ Regenerate')
        : null,
    );
  }

  function toggleEdit(header) {
    const existing = header.querySelector('.trip-edit');
    if (existing) {
      existing.remove();
      return;
    }
    const { trip } = tctx.trip;
    const nameInput = el('input', { class: 'input', type: 'text', maxlength: '120', value: trip.name });
    const startInput = el('input', { class: 'input', type: 'date', value: trip.start_date });
    const endInput = el('input', { class: 'input', type: 'date', value: trip.end_date });
    const currencyInput = el('input', { class: 'input input-currency', type: 'text', maxlength: '3', value: trip.currency || 'USD', 'aria-label': 'Currency code' });
    const errorEl = el('p', { class: 'form-error' });
    const saveBtn = el('button', { class: 'btn btn-primary', type: 'submit' }, 'Save changes');

    async function onSubmit(e) {
      e.preventDefault();
      errorEl.textContent = '';
      const name = nameInput.value.trim();
      const start_date = startInput.value;
      const end_date = endInput.value;
      const currency = currencyInput.value.trim().toUpperCase() || 'USD';
      if (!name) return (errorEl.textContent = 'Name cannot be empty.');
      if (end_date < start_date) return (errorEl.textContent = 'End date must be on or after the start date.');
      if (!/^[A-Z]{3}$/.test(currency)) return (errorEl.textContent = 'Currency must be a 3-letter code, e.g. USD.');
      saveBtn.disabled = true;
      saveBtn.textContent = 'Saving…';
      try {
        await api.trips.update(tctx.tripId, { name, start_date, end_date, currency });
        toast('Trip updated', 'success');
        await tctx.refreshTrip();
      } catch (err) {
        errorEl.textContent = err.message;
        saveBtn.disabled = false;
        saveBtn.textContent = 'Save changes';
      }
    }

    const editBox = el(
      'form',
      { class: 'trip-edit', onSubmit },
      el(
        'div',
        { class: 'form-row' },
        el('label', { class: 'field field-grow' }, el('span', { class: 'field-label' }, 'Name'), nameInput),
      ),
      el(
        'div',
        { class: 'form-row' },
        el('label', { class: 'field' }, el('span', { class: 'field-label' }, 'Start date'), startInput),
        el('label', { class: 'field' }, el('span', { class: 'field-label' }, 'End date'), endInput),
        el('label', { class: 'field field-currency' }, el('span', { class: 'field-label' }, 'Currency'), currencyInput),
      ),
      el('p', { class: 'hint muted' }, 'Changing the range regenerates the calendar; entries outside the new range are kept and flagged.'),
      errorEl,
      el('div', { class: 'form-actions' }, saveBtn),
    );
    header.appendChild(editBox);
  }

  async function onRemoveMember(member) {
    if (!window.confirm(`Remove ${member.display_name} from this trip?`)) return;
    try {
      await api.trips.removeMember(tctx.tripId, member.id);
      toast(`${member.display_name} removed`, 'success');
      await tctx.refreshTrip();
    } catch (err) {
      toast(err.message);
    }
  }

  async function onDelete() {
    const { trip } = tctx.trip;
    if (!window.confirm(`Delete "${trip.name}"? This removes all its entries and cannot be undone.`)) return;
    try {
      await api.trips.remove(tctx.tripId);
      toast('Trip deleted', 'success');
      ctx.navigate('#/trips');
    } catch (err) {
      toast(err.message);
    }
  }
}