// Plan 5: per-Space companion chat. Chat mechanics live in agent_chat.js; this
// file owns only the collapsible rail chrome + Space-change re-init.
import { el, mount } from '../dom.js';
import { state, on } from '../state.js';
import { wireAgentChat } from './agent_chat.js';

const COLLAPSE_KEY = 'void_rail_collapsed';
const COMPANION_LABELS = {
  search: '🔍 searching', read: '📄 reading',
  context: '🧭 looking at this view', propose_change: '📝 drafting a change'
};

export async function renderRightrail(root) {
  const shell = document.getElementById('shell');
  let collapsed = localStorage.getItem(COLLAPSE_KEY) === 'true';
  if (collapsed) shell.classList.add('rail-collapsed');
  const toggle = () => {
    collapsed = !collapsed;
    localStorage.setItem(COLLAPSE_KEY, String(collapsed));
    shell.classList.toggle('rail-collapsed', collapsed);
  };

  const log = el('div', { class: 'rail-log' });
  const input = el('textarea', { class: 'rail-input', rows: 1, placeholder: 'Ask the companion…' });
  const header = el('div', { class: 'rail-hd' },
    el('span', { class: 'who' }, '◆ Companion'),
    el('span', { class: 'chev', onclick: toggle, title: 'Collapse' }, '⟩'));

  mount(root, el('div', { class: 'rail-toggle', onclick: toggle, title: 'Companion' }, 'CRADLE'),
    el('div', { class: 'rail-chat' }, header, log, el('div', { class: 'rail-inputwrap' }, input)));

  // (Re)wire the chat whenever the active Space changes.
  async function initChat(spaceId) {
    if (!spaceId) {
      mount(log, el('p', { class: 'muted' }, 'Open a Space to chat with its companion.'));
      return;
    }
    const chat = wireAgentChat({
      logEl: log, inputEl: input,
      historyUrl: `/api/spaces/${spaceId}/companion`,
      turnUrl: `/api/spaces/${spaceId}/companion/turn`,
      agentName: 'Companion', showDrafts: true, toolLabels: COMPANION_LABELS,
      turnBody: (text) => ({ text, view: state.view || null })
    });
    await chat.load();
  }

  // The state bus replays its last value on subscribe, so this fires for the
  // initial route() call and every later navigation. Only re-init when the id
  // actually changes so navigating within a Space doesn't wipe the conversation.
  let lastSpaceId; let inited = false;
  on('space-active', (spaceId) => {
    if (inited && spaceId === lastSpaceId) return;
    inited = true;
    lastSpaceId = spaceId;
    initChat(spaceId);
  });
}