// Search past conversations (devdesk#24): every Claude conversation on this host
// (DevDesk and code-server), by what you asked, what Claude said, the commands
// it ran and their output. Resume one in a new session, or fork it.

import { runCommand, sessionAction } from './connection.js';
import { parseListOutput, slugify } from './protocol.js';
import { el } from './dom.js';
import { ago } from './sessions.js';
import { openDialog, toast } from './ui.js';

const ROLE = { you: 'You', claude: 'Claude', command: 'Ran', output: 'Output' };

// Text with every case-insensitive occurrence of `query` in <mark>.
function highlight(text, query) {
  const nodes = [];
  const lower = text.toLowerCase();
  const q = query.toLowerCase();
  let at = 0;
  for (let i = lower.indexOf(q); i >= 0 && q; i = lower.indexOf(q, at)) {
    if (i > at) nodes.push(text.slice(at, i));
    nodes.push(el('mark', {}, text.slice(i, i + q.length)));
    at = i + q.length;
  }
  nodes.push(text.slice(at));
  return nodes;
}

const day = (iso) => (iso ? new Date(iso).toLocaleDateString(undefined, { year: 'numeric', month: 'short', day: 'numeric' }) : '');

// hooks: sessions() -> session list, open(name), refresh()
export function openHistory(hooks) {
  const input = el('input', { class: 'lt-input dd-history-input', type: 'search', placeholder: 'What did you work on? e.g. "NFS mount", "pct exec 167", "no_root_squash"', spellcheck: 'false', autocomplete: 'off' });
  const status = el('div', { class: 'dd-dialog-hint' }, 'Searches every Claude conversation on this host: your prompts, Claude\'s answers, the commands it ran and their output.');
  const results = el('div', { class: 'dd-history-results' });
  let seq = 0;
  let timer = 0;
  let close = null;

  const liveSessionFor = (id) => hooks.sessions().find((s) => s.running && s.claude_session_id === id)?.name;

  // Resume or fork: confirm the new session's name inline, then open it.
  const start = (result, fork, holder) => {
    const name = el('input', { class: 'lt-input', value: slugify(`${fork ? 'fork-' : ''}${result.title}`).slice(0, 40) || 'resumed', spellcheck: 'false' });
    const go = async () => {
      const value = slugify(name.value);
      if (!value) return;
      try {
        await sessionAction('resume-convo', value, result.id, ...(fork ? ['fork'] : []));
        close?.();
        toast.success(`${fork ? 'Forked' : 'Resumed'} “${result.title.slice(0, 40)}” in ${value}`);
        hooks.refresh();
        hooks.open(value);
      } catch (error) {
        toast.error(error.message);
      }
    };
    name.addEventListener('keydown', (event) => {
      if (event.key === 'Enter') {
        event.preventDefault();
        go();
      }
    });
    holder.replaceChildren(el('span', { class: 'dd-dialog-hint' }, `New session for ${fork ? 'a fork of ' : ''}this conversation:`), name,
      el('button', { type: 'button', class: 'lt-btn lt-btn-primary lt-btn-sm', onclick: go }, fork ? 'Fork' : 'Resume'));
    name.focus();
    name.select();
  };

  const render = (data) => {
    if (!data.results.length) {
      results.replaceChildren(el('div', { class: 'dd-files-msg' }, `Nothing found for “${data.query}”.`));
      return;
    }
    results.replaceChildren(...data.results.map((r) => {
      const live = liveSessionFor(r.id);
      const actions = el('div', { class: 'dd-history-actions' });
      const fill = () => actions.replaceChildren(
        live
          ? el('button', { type: 'button', class: 'lt-btn lt-btn-primary lt-btn-sm', onclick: () => { close?.(); hooks.open(live); } }, `Open ${live}`)
          : el('button', { type: 'button', class: 'lt-btn lt-btn-primary lt-btn-sm', onclick: () => start(r, false, actions) }, 'Resume…'),
        el('button', { type: 'button', class: 'lt-btn lt-btn-sm', onclick: () => start(r, true, actions), title: 'Continue as a new conversation; the original stays as it is' }, 'Fork…'),
        el('button', {
          type: 'button', class: 'lt-btn lt-btn-ghost lt-btn-sm',
          onclick: () => navigator.clipboard?.writeText(`claude --resume ${r.id}`).then(() => toast.success('Copied the resume command')),
        }, 'Copy command'));
      fill();
      return el('div', { class: 'dd-history-item' },
        el('div', { class: 'dd-history-title' }, r.title),
        el('div', { class: 'dd-history-meta' },
          [r.cwd, day(r.started), `updated ${ago(r.updated)}${ago(r.updated) === 'now' ? '' : ' ago'}`, `${r.hits} match${r.hits === 1 ? '' : 'es'}`, live ? `open in ${live}` : '']
            .filter(Boolean).join(' · ')),
        ...r.matches.map((m) => el('div', { class: `dd-history-snippet is-${m.role}` },
          el('span', { class: 'dd-history-role' }, ROLE[m.role] ?? m.role), el('span', {}, ...highlight(m.snippet, data.query)))),
        actions);
    }));
  };

  const search = async () => {
    const query = input.value.trim();
    if (query.length < 2) return;
    const mine = ++seq;
    status.textContent = `Searching for “${query}”…`;
    try {
      const data = parseListOutput(await runCommand(['--search', query], 30000));
      if (mine !== seq) return;
      const n = data.results.length;
      status.textContent = `${n}${n === 25 ? '+' : ''} conversation${n === 1 ? ' mentions' : 's mention'} “${query}”, newest first.`;
      render(data);
    } catch (error) {
      if (mine === seq) status.textContent = error.message;
    }
  };
  input.addEventListener('input', () => {
    clearTimeout(timer);
    timer = setTimeout(search, 500);
  });
  input.addEventListener('keydown', (event) => {
    if (event.key === 'Enter') {
      event.preventDefault();
      clearTimeout(timer);
      search();
    }
  });

  openDialog({
    title: 'Search past conversations',
    className: 'is-wide',
    body: el('div', { class: 'dd-history' }, input, status, results),
    actions: [{ label: 'Close', value: null }],
    onOpen: (overlay) => {
      close = () => overlay.querySelector('.lt-modal-close')?.click();
      return input;
    },
  });
}