// ── DOM Helpers ──

const $ = (sel) => document.querySelector(sel);
const chatEl = () => $('#chat');
const metaEl = () => $('#meta');

// ── Markdown ──

marked.setOptions({ breaks: true, gfm: true });

function renderMarkdown(text) {
  if (!text) return '';
  return marked.parse(text.trim());
}

function scrollDown() {
  const chat = chatEl();
  chat.scrollTop = chat.scrollHeight;
}

function esc(s) {
  const d = document.createElement('div');
  d.textContent = s;
  return d.innerHTML;
}

function truncate(s, max) {
  return s && s.length > max ? s.substring(0, max) + '...' : (s || '');
}

// ── Message Bubbles ──

function addUserBubble(text, streamed = false) {
  const div = document.createElement('div');
  div.className = 'msg user';
  if (streamed) div.classList.add('streamed');
  div.textContent = (text || '').trim();
  chatEl().appendChild(div);
  scrollDown();
}

function addAssistantBubble(text) {
  const div = document.createElement('div');
  div.className = 'msg assistant markdown';
  div.innerHTML = renderMarkdown(text);
  chatEl().appendChild(div);
  scrollDown();
  return div;
}

function addErrorBubble(text, streamed = false) {
  const div = document.createElement('div');
  div.className = 'msg system-info';
  if (streamed) div.classList.add('streamed');
  div.style.color = 'var(--dangerous)';
  div.textContent = (text || '').trim();
  chatEl().appendChild(div);
  scrollDown();
}

function addWarningBubble(text, streamed = false) {
  const div = document.createElement('div');
  div.className = 'msg system-info';
  if (streamed) div.classList.add('streamed');
  div.style.color = 'var(--warning)';
  div.textContent = (text || '').trim();
  chatEl().appendChild(div);
  scrollDown();
}

// ── Streaming Bubble ──

let _streamDiv = null;
let _streamText = '';

function startStreamBubble() {
  _streamDiv = document.createElement('div');
  _streamDiv.className = 'msg assistant markdown streamed';
  _streamDiv.innerHTML = '<span class="cursor"></span>';
  _streamText = '';
  chatEl().appendChild(_streamDiv);
  scrollDown();
}

function appendToStream(text) {
  if (!_streamDiv) startStreamBubble();
  _streamText += text;
  _streamDiv.innerHTML = renderMarkdown(_streamText);
  const cursor = document.createElement('span');
  cursor.className = 'cursor';
  _streamDiv.appendChild(cursor);
  scrollDown();
}

function endStreamBubble() {
  if (_streamDiv) {
    const cursor = _streamDiv.querySelector('.cursor');
    if (cursor) cursor.remove();
    if (!_streamText.trim()) _streamDiv.remove();
    else _streamDiv.innerHTML = renderMarkdown(_streamText);
  }
  _streamDiv = null;
  _streamText = '';
}

// ── Tool Boxes ──

function addToolBoxLoading(name) {
  const div = document.createElement('div');
  div.className = 'tool-box streamed';
  div.innerHTML = '<span class="tool-name">' + esc(name) + '</span> <span class="tool-spinner">⏳</span>';
  chatEl().appendChild(div);
  scrollDown();
  return div;
}

function renderToolBoxContent(div, name, inputJson, result, isError) {
  let parsedInput = null;
  try { parsedInput = JSON.parse(inputJson); } catch {}

  const header = document.createElement('div');
  header.className = 'tool-box-header';

  const nameSpan = document.createElement('span');
  nameSpan.className = 'tool-name';
  nameSpan.textContent = name;
  header.appendChild(nameSpan);

  if (isError) {
    const errSpan = document.createElement('span');
    errSpan.className = 'tool-error-badge';
    errSpan.textContent = 'error';
    header.appendChild(errSpan);
  }

  div.innerHTML = '';
  div.appendChild(header);

  let foldTarget = null;

  if (name === 'edit_file' && parsedInput && parsedInput.path) {
    const pathSpan = document.createElement('span');
    pathSpan.className = 'tool-input';
    pathSpan.textContent = parsedInput.path;
    header.appendChild(pathSpan);

    const diff = buildEditDiff(parsedInput.old_text || '', parsedInput.new_text || '');
    diff.hidden = true;
    div.appendChild(diff);
    foldTarget = diff;

  } else if (name === 'write_file' && parsedInput && parsedInput.path) {
    const pathSpan = document.createElement('span');
    pathSpan.className = 'tool-input';
    pathSpan.textContent = parsedInput.path;
    header.appendChild(pathSpan);

    const content = parsedInput.content || '';
    const lines = content.split('\n');
    const lineCount = lines.length;
    const charCount = content.length;

    const meta = document.createElement('span');
    meta.className = 'tool-write-meta';
    meta.textContent = lineCount + ' Zeilen, ' + charCount + ' Zeichen';
    header.appendChild(meta);

    const preview = buildWritePreview(content);
    preview.hidden = true;
    div.appendChild(preview);
    foldTarget = preview;

  } else {
    // Standard: path/command als input anzeigen
    let inputLabel = '';
    if (parsedInput) {
      inputLabel = parsedInput.path || parsedInput.command || JSON.stringify(parsedInput).substring(0, 120);
    } else {
      inputLabel = truncate(inputJson, 120);
    }
    if (inputLabel) {
      const inputSpan = document.createElement('span');
      inputSpan.className = 'tool-input';
      inputSpan.textContent = inputLabel;
      header.appendChild(inputSpan);
    }

    const resultDiv = document.createElement('div');
    resultDiv.className = 'tool-result' + (isError ? ' tool-error' : '');
    resultDiv.textContent = result ? truncate(result, 300) : '';
    resultDiv.hidden = true;
    div.appendChild(resultDiv);
    foldTarget = resultDiv;
  }

  if (foldTarget) {
    header.style.cursor = 'pointer';
    header.addEventListener('click', () => {
      foldTarget.hidden = !foldTarget.hidden;
    });
  }
}

function buildEditDiff(oldText, newText) {
  const oldLines = oldText.split('\n');
  const newLines = newText.split('\n');

  const container = document.createElement('div');
  container.className = 'tool-diff';

  // Entfernte Zeilen (-)
  for (const line of oldLines) {
    const row = document.createElement('div');
    row.className = 'diff-line diff-removed';
    const marker = document.createElement('span');
    marker.className = 'diff-marker';
    marker.textContent = '-';
    const content = document.createElement('span');
    content.className = 'diff-content';
    content.textContent = line;
    row.appendChild(marker);
    row.appendChild(content);
    container.appendChild(row);
  }

  // Hinzugefügte Zeilen (+)
  for (const line of newLines) {
    const row = document.createElement('div');
    row.className = 'diff-line diff-added';
    const marker = document.createElement('span');
    marker.className = 'diff-marker';
    marker.textContent = '+';
    const content = document.createElement('span');
    content.className = 'diff-content';
    content.textContent = line;
    row.appendChild(marker);
    row.appendChild(content);
    container.appendChild(row);
  }

  return container;
}

function buildWritePreview(content) {
  const lines = content.split('\n');

  const container = document.createElement('div');
  container.className = 'tool-diff';

  for (const line of lines) {
    const row = document.createElement('div');
    row.className = 'diff-line diff-added';
    const marker = document.createElement('span');
    marker.className = 'diff-marker';
    marker.textContent = '+';
    const contentSpan = document.createElement('span');
    contentSpan.className = 'diff-content';
    contentSpan.textContent = line;
    row.appendChild(marker);
    row.appendChild(contentSpan);
    container.appendChild(row);
  }

  return container;
}

function finishToolBox(div, data) {
  if (!div) return;
  renderToolBoxContent(div, data.name, data.input, data.result, data.isError);
  scrollDown();
}

function addToolBoxStatic(name, input, result, isError) {
  const div = document.createElement('div');
  div.className = 'tool-box';
  renderToolBoxContent(div, name, input, result, isError);
  chatEl().appendChild(div);
  scrollDown();
}

function appendToolResult(result, isError) {
  // Letzten tool-box im Chat finden und Result in die bereits vorhandene .tool-result-Div schreiben
  const boxes = chatEl().querySelectorAll('.tool-box');
  const lastBox = boxes[boxes.length - 1];
  if (!lastBox) return;

  // Wenn Diff vorhanden (edit_file/write_file) → kein Result anhängen
  if (lastBox.querySelector('.tool-diff')) return;

  const existing = lastBox.querySelector('.tool-result');
  if (existing) {
    existing.textContent = truncate(result, 300);
    if (isError) existing.classList.add('tool-error');
  } else {
    const resultDiv = document.createElement('div');
    resultDiv.className = 'tool-result' + (isError ? ' tool-error' : '');
    resultDiv.textContent = truncate(result, 300);
    resultDiv.hidden = true;
    lastBox.appendChild(resultDiv);
  }
}

// ── Streamed Elements ──

function removeStreamedElements() {
  chatEl().querySelectorAll('.streamed').forEach(el => el.remove());
}

// ── Attachment Indicator ──

function addAttachmentIndicator(messageId, count, namesJson) {
  const chat = chatEl();
  const lastMsg = chat.lastElementChild;
  if (!lastMsg) return;

  let names = [];
  try { if (namesJson) names = JSON.parse(namesJson); } catch {}

  const indicator = document.createElement('div');
  indicator.className = 'attachment-indicator';

  const nameList = names.filter(n => n).join(', ');
  indicator.textContent = `📎 ${count} Datei${count > 1 ? 'en' : ''}` + (nameList ? `: ${nameList}` : '');
  indicator.style.cursor = 'pointer';
  indicator.title = 'Klicken zum Anzeigen';
  indicator.addEventListener('click', () => loadAndShowAttachments(messageId, indicator));
  lastMsg.appendChild(indicator);
}

async function loadAndShowAttachments(messageId, indicator) {
  if (indicator.dataset.loaded) return;
  indicator.dataset.loaded = '1';
  indicator.textContent = '📎 Laden...';

  try {
    const resp = await fetch(`/api/attachments/${messageId}`);
    const attachments = await resp.json();

    const container = document.createElement('div');
    container.className = 'attachment-container';

    for (const att of attachments) {
      if (att.type === 'image') {
        const img = document.createElement('img');
        img.src = `data:${att.mediaType};base64,${att.data}`;
        img.className = 'attachment-image';
        img.title = att.fileName || 'Bild';
        container.appendChild(img);
      } else {
        const link = document.createElement('a');
        link.href = `data:${att.mediaType};base64,${att.data}`;
        link.download = att.fileName || 'datei';
        link.className = 'attachment-file';
        link.textContent = `📄 ${att.fileName || 'Dokument'}`;
        container.appendChild(link);
      }
    }

    indicator.textContent = `📎 ${attachments.length} Datei${attachments.length > 1 ? 'en' : ''}`;
    indicator.parentElement.appendChild(container);
  } catch (e) {
    indicator.textContent = '📎 Fehler beim Laden';
    indicator.dataset.loaded = '';
  }
}

// ── Meta Bar ──

function setMeta(text) {
  metaEl().textContent = text;
}

function setMetaHtml(html) {
  metaEl().innerHTML = html;
}

// ── Archive Button ──

function showArchiveLoadButton() {
  const existing = chatEl().querySelector('.archive-load-btn');
  if (existing) existing.remove();

  const btn = document.createElement('button');
  btn.className = 'archive-load-btn';
  btn.textContent = '📦 Archivierte Nachrichten laden';
  btn.addEventListener('click', loadLatestArchive);

  // Immer ganz oben im Chat
  chatEl().prepend(btn);
}

function removeArchiveLoadButton() {
  const btn = chatEl().querySelector('.archive-load-btn');
  if (btn) btn.remove();
}