// "💡 Suggestions" modal for the checklist card — fetches the deterministic
// packing advice (GET .../checklist/suggestions), lets the user tick which
// ones to add and whether they go in as shared or personal items, then bulk
// adds them (POST .../checklist/suggestions). Kept as its own module so
// checklist.js stays small (mirrors dayEditor.js's costForm/waypoints split).
import { api } from '../api.js';
import { el, mount, loading, errorBox, toast } from '../dom.js';

export function openSuggestionsModal(tctx, onAdded) {
  const overlay = el('div', { class: 'overlay overlay-center' });
  const modal = el('div', { class: 'modal', role: 'dialog', 'aria-modal': 'true' });
  overlay.appendChild(modal);
  document.body.appendChild(overlay);
  document.body.classList.add('no-scroll');

  function close() {
    document.body.classList.remove('no-scroll');
    overlay.remove();
    document.removeEventListener('keydown', onKey);
  }
  function onKey(e) {
    if (e.key === 'Escape') close();
  }
  document.addEventListener('keydown', onKey);
  overlay.addEventListener('click', (e) => {
    if (e.target === overlay) close();
  });

  load();

  async function load() {
    mount(modal, modalHead(), loading('Loading suggestions…'));
    try {
      const data = await api.checklist.suggestions(tctx.tripId);
      draw(data.suggestions || []);
    } catch (err) {
      mount(modal, modalHead(), errorBox(err.message, load));
    }
  }

  function modalHead() {
    return el(
      'div',
      { class: 'slideover-head' },
      el('h2', {}, '💡 Packing suggestions'),
      el('button', { class: 'icon-btn', type: 'button', title: 'Close', onClick: close }, '×'),
    );
  }

  function draw(suggestions) {
    let scope = 'shared'; // 'shared' | 'personal' — applies to the whole batch
    const checks = new Map(); // suggestion key -> its (enabled) checkbox

    const groups = new Map();
    for (const s of suggestions) {
      if (!groups.has(s.category)) groups.set(s.category, []);
      groups.get(s.category).push(s);
    }

    const listEl = el('div', { class: 'suggest-list' });
    if (!suggestions.length) {
      listEl.appendChild(el('p', { class: 'muted' }, 'No suggestions yet — add some entries to the trip first.'));
    }
    for (const [category, items] of groups) {
      const rows = el('div', { class: 'suggest-rows' });
      for (const s of items) {
        rows.appendChild(suggestionRow(s, checks));
      }
      listEl.appendChild(el('div', { class: 'suggest-category' }, el('h3', {}, category), rows));
    }

    const sharedRadio = el('input', { type: 'radio', name: 'suggest-scope', checked: true });
    const personalRadio = el('input', { type: 'radio', name: 'suggest-scope' });
    sharedRadio.addEventListener('change', () => { if (sharedRadio.checked) scope = 'shared'; });
    personalRadio.addEventListener('change', () => { if (personalRadio.checked) scope = 'personal'; });
    const scopeRow = el(
      'div',
      { class: 'suggest-scope' },
      el('label', {}, sharedRadio, 'Shared'),
      el('label', {}, personalRadio, '🔒 Personal to me'),
    );

    const errorEl = el('p', { class: 'form-error' });
    const cancelBtn = el('button', { class: 'btn btn-ghost', type: 'button', onClick: close }, 'Cancel');
    const addBtn = el('button', { class: 'btn btn-primary', type: 'button', onClick: onAddSelected }, 'Add selected');

    async function onAddSelected() {
      errorEl.textContent = '';
      const keys = [...checks.entries()].filter(([, cb]) => cb.checked).map(([key]) => key);
      if (!keys.length) return (errorEl.textContent = 'Pick at least one suggestion.');
      addBtn.disabled = true;
      addBtn.textContent = 'Adding…';
      try {
        await api.checklist.addSuggestions(tctx.tripId, keys, scope === 'personal');
        toast(`Added ${keys.length} item${keys.length === 1 ? '' : 's'}`, 'success');
        close();
        await onAdded();
      } catch (err) {
        errorEl.textContent = err.message;
        addBtn.disabled = false;
        addBtn.textContent = 'Add selected';
      }
    }

    mount(modal, modalHead(), listEl, suggestions.length ? scopeRow : null, errorEl, el('div', { class: 'form-actions' }, cancelBtn, addBtn));
  }

  // One suggestion row: checkbox (ticked + disabled if already added), text +
  // qty, and the reason as muted subtext. Registers its checkbox in `checks`
  // only when selectable (not already added), for onAddSelected to read.
  function suggestionRow(s, checks) {
    const disabled = !!s.added;
    const check = el('input', {
      type: 'checkbox', class: 'suggest-check', checked: disabled, disabled,
    });
    if (!disabled) checks.set(s.key, check);
    return el(
      'label',
      { class: `suggest-row${disabled ? ' added' : ''}` },
      check,
      el(
        'div',
        { class: 'suggest-body' },
        el('span', { class: 'suggest-text' }, s.text, s.qty != null ? el('span', { class: 'suggest-qty' }, `×${s.qty}`) : null),
        el('div', { class: 'suggest-reason muted' }, s.reason),
      ),
    );
  }
}