import { badge, rowHTML, setRows, safe, showToast } from './helpers.js';
import { api } from './api.js';

const liveSockets = new Map();
let reconcileTimer = null;

function closeForSid(sid) {
  const entry = liveSockets.get(sid);
  if (!entry) return;
  try { entry.obs && entry.obs.close(); } catch {}
  try { entry.task && entry.task.close(); } catch {}
  liveSockets.delete(sid);
}

export function stopAllAdminWatches() {
  if (reconcileTimer) { clearInterval(reconcileTimer); reconcileTimer = null; }
  for (const sid of Array.from(liveSockets.keys())) closeForSid(sid);
}

function setBadge(cell, val) {
  if (!cell) return;
  cell.innerHTML = val;
}

export async function renderVMAdmin() {
  stopAllAdminWatches();

  const data = await api.listAllVmct();
  const arr = Array.isArray(data.all) ? data.all : [];
  const availableNodes = Array.isArray(data.nodes) ? data.nodes : [];
  const tbody = document.querySelector('#vm-admin tbody');
  if (!arr.length) { setRows(tbody, [rowHTML(['Brak VM/CT'])]); return; }

  const rows = arr.map(x => {
    const sid = safe(x.sid), type = safe(x.type), name = safe(x.name), node = safe(x.node);
    const st = /running/i.test(x.status || '') ? badge(x.status,'ok') : badge(x.status || '—','dark');
    const actions = `
      <div class="btn-group btn-group-sm" role="group">
        <button class="btn btn-outline-secondary act-unlock">Unlock</button>
        <button class="btn btn-outline-success act-start">Start</button>
        <button class="btn btn-outline-warning act-shutdown">Shutdown</button>
        <button class="btn btn-outline-danger act-stop">Stop</button>
      </div>`;
    const sel = `<select class="form-select form-select-sm target-node" style="min-width:160px">
      ${availableNodes.map(n => `<option value="${n}" ${n === x.node ? 'disabled selected' : ''}>${n}${n === x.node ? ' (src)' : ''}</option>`).join('')}
    </select>`;
    const tools = `<div class="d-flex align-items-center gap-2">
      <button class="btn btn-outline-primary btn-sm act-migrate">Migrate (offline)</button>
      <button class="btn btn-outline-secondary btn-sm act-status">Status</button>
    </div>`;
    return rowHTML([sid, type.toUpperCase(), name, node, st, actions, sel, tools], `data-sid="${sid}"`);
  });

  setRows(tbody, rows);

  Array.from(tbody.querySelectorAll('tr[data-sid]')).forEach(tr => {
    const sid = tr.getAttribute('data-sid');
    const colSpan = tr.children.length;
    const nodeCell  = tr.children[3];
    const badgeCell = tr.children[4];
    const targetSel = tr.querySelector('.target-node');

    let sub = tr.nextElementSibling;
    if (!sub || !sub.classList.contains('mig-row')) {
      sub = document.createElement('tr'); sub.className = 'mig-row d-none';
      const td = document.createElement('td'); td.colSpan = colSpan;
      td.innerHTML = '<div class="p-3 border rounded bg-body-tertiary"><div class="fw-semibold mb-1">Task status</div><pre class="small mb-0 mig-log">—</pre></div>';
      sub.appendChild(td); tr.parentNode.insertBefore(sub, tr.nextSibling);
    }
    const logPre = sub.querySelector('.mig-log');
    const toggleSub = (show) => sub.classList.toggle('d-none', !show);

    const setRowBusy = (busy) => {
      const nameCell = tr.children[2];
      let spin = nameCell.querySelector('.op-spin');
      if (busy && !spin) {
        const span = document.createElement('span');
        span.className = 'op-spin spinner-border spinner-border-sm align-middle ms-2';
        span.setAttribute('role','status'); span.setAttribute('aria-hidden','true');
        nameCell.appendChild(span);
      }
      if (!busy && spin) spin.remove();
    };

    const rebuildTargetSelect = (currentNode) => {
      if (!targetSel) return;
      const current = currentNode || (nodeCell?.textContent || '').trim();
      const html = availableNodes.map(n =>
        `<option value="${n}" ${n === current ? 'disabled selected' : ''}>${n}${n === current ? ' (src)' : ''}</option>`).join('');
      targetSel.innerHTML = html;
      const idx = Array.from(targetSel.options).findIndex(o => !o.disabled);
      if (idx >= 0) targetSel.selectedIndex = idx;
    };

    const getTarget = () => targetSel?.value || '';

    const openTaskWS = (upid, node) => {
      if (!upid) return;
      toggleSub(true);
      logPre.textContent = `UPID: ${upid} @ ${node}\n`;

      const entry = liveSockets.get(sid) || {};
      try { entry.task && entry.task.close(); } catch {}
      const wsTask = new WebSocket(api.wsTaskURL(upid, node));
      entry.task = wsTask;
      liveSockets.set(sid, entry);

      wsTask.onmessage = (ev) => {
        try {
          const msg = JSON.parse(ev.data);
          if (msg.type === 'log' && msg.line) {
            logPre.textContent += msg.line + '\n';
            logPre.scrollTop = logPre.scrollHeight;
          } else if (msg.type === 'status' && msg.status) {
            const ok = String(msg.status.exitstatus||'').toUpperCase() === 'OK';
            const s  = String(msg.status.status||'').toLowerCase();
            setBadge(badgeCell, ok ? badge('running','ok') :
              (s === 'stopped' ? badge('stopped','dark') : badge('working','info')));
          } else if (msg.type === 'done') {
            const ok = !!msg.ok;
            setBadge(badgeCell, ok ? badge('running','ok') : badge('error','err'));
            setRowBusy(false);
            setTimeout(() => toggleSub(false), 1500);
          }
        } catch {}
      };
    };

    const ensureWatchOn = () => {
      const existing = liveSockets.get(sid);
      if (existing && existing.obs && existing.obs.readyState <= 1) return;

      closeForSid(sid);

      const wsObs = new WebSocket(api.wsObserveURL(sid));
      liveSockets.set(sid, { obs: wsObs, task: null });

      wsObs.onmessage = (ev) => {
        try {
          const msg = JSON.parse(ev.data);

          if (msg.type === 'vm' && msg.current) {
            const st = String(msg.current.status || msg.current.qmpstatus || '').toLowerCase();
            const ok = /running|online|started/.test(st);
            setBadge(badgeCell, ok ? badge('running','ok') :
              (/stopp|shutdown|offline/.test(st) ? badge('stopped','dark') : badge(st||'—','info')));
          }
          else if (msg.type === 'task-start' && msg.upid && msg.node) {
            openTaskWS(msg.upid, msg.node);
          }
          else if (msg.type === 'task' && msg.upid && msg.status) {
            const stopped = String(msg.status||'').toLowerCase() === 'stopped';
            if (stopped && typeof msg.exitstatus !== 'undefined') {
              const ok = String(msg.exitstatus||'').toUpperCase() === 'OK';
              setBadge(badgeCell, ok ? badge('running','ok') : badge('error','err'));
            } else {
              setBadge(badgeCell, badge('working','info'));
            }
          }
          else if (msg.type === 'moved' && msg.new_node) {
            if (nodeCell) nodeCell.textContent = msg.new_node;
            rebuildTargetSelect(msg.new_node);
          }
          else if (msg.type === 'done' && typeof msg.ok === 'boolean') {
            setBadge(badgeCell, msg.ok ? badge('running','ok') : badge('error','err'));
          }

        } catch {}
      };

      wsObs.onclose = () => {
        const e = liveSockets.get(sid);
        if (e && e.obs === wsObs) {
          liveSockets.set(sid, { obs: null, task: e.task || null });
        }
      };
    };

    const doAction = async (action, withTarget=false) => {
      setRowBusy(true);
      try {
        const target = withTarget ? getTarget() : undefined;

        ensureWatchOn();
        if (action !== 'unlock') {
          setBadge(badgeCell, badge('working','info'));
          toggleSub(true);
        }

        const resp = await api.vmAction(sid, action, target);
        if (!resp.ok) throw new Error(resp.error || 'unknown');

        if (!resp.upid) {
          logPre.textContent = `Waiting for task… (${action})\n`;
          setRowBusy(false);
          return;
        }

        openTaskWS(resp.upid, resp.source_node);

      } catch (e) {
        showToast('Error', 'ERROR: ' + (e.message || e), 'danger');
        setRowBusy(false);
        toggleSub(false);
      }
    };

    tr.querySelector('.act-unlock')?.addEventListener('click', () => doAction('unlock'));
    tr.querySelector('.act-start')?.addEventListener('click',   () => doAction('start'));
    tr.querySelector('.act-stop')?.addEventListener('click',    () => doAction('stop'));
    tr.querySelector('.act-shutdown')?.addEventListener('click',() => doAction('shutdown'));
    tr.querySelector('.act-migrate')?.addEventListener('click', () => doAction('migrate', true));

    tr.querySelector('.act-status')?.addEventListener('click', () => toggleSub(sub.classList.contains('d-none')));

    ensureWatchOn();
  });

  reconcileTimer = setInterval(async () => {
    try {
      const latest = await api.listAllVmct();
      const all = Array.isArray(latest.all) ? latest.all : [];
      const bySid = new Map(all.map(x => [String(x.sid), x]));

      Array.from(tbody.querySelectorAll('tr[data-sid]')).forEach(tr => {
        const sid = tr.getAttribute('data-sid');
        const rowData = bySid.get(sid);
        if (!rowData) return;

        const nodeCell  = tr.children[3];
        const badgeCell = tr.children[4];
        const targetSel = tr.querySelector('.target-node');

        const newNode = String(rowData.node || '').trim();
        if (nodeCell && newNode && nodeCell.textContent.trim() !== newNode) {
          nodeCell.textContent = newNode;
          if (targetSel) {
            const options = Array.from(targetSel.options);
            options.forEach(o => { o.disabled = (o.value === newNode); o.selected = (o.value === newNode); });
            const idx = options.findIndex(o => !o.disabled);
            if (idx >= 0) targetSel.selectedIndex = idx;
          }
        }

        const running = /running/i.test(rowData.status || '');
        const currentBadge = badgeCell?.innerText?.toLowerCase() || '';
        const isWorking = currentBadge.includes('working');
        if (badgeCell && !isWorking) {
          setBadge(badgeCell, running ? badge('running','ok') : badge(rowData.status || '—','dark'));
        }

        const existing = liveSockets.get(sid);
        if (!(existing && existing.obs && existing.obs.readyState <= 1)) {
          const wsObs = new WebSocket(api.wsObserveURL(sid));
          liveSockets.set(sid, { obs: wsObs, task: existing?.task || null });
          wsObs.onmessage = () => {};
          wsObs.onerror = () => {};
        }
      });

    } catch {}
  }, 3000);

  window.addEventListener('beforeunload', stopAllAdminWatches, { once: true });
}