// ── Friends page ──────────────────────────────────────────────────────────────

const addFriendModal = new bootstrap.Modal('#addFriendModal');
let _currentTab = 'friends';

// ── Tab switching ─────────────────────────────────────────────────────────────

document.querySelectorAll('#friendTabs .nav-link').forEach(btn => {
  btn.addEventListener('click', () => {
    document.querySelectorAll('#friendTabs .nav-link').forEach(b => b.classList.remove('active'));
    btn.classList.add('active');
    _currentTab = btn.dataset.tab;
    document.getElementById('tabFriends').classList.toggle('d-none',   _currentTab !== 'friends');
    document.getElementById('tabRequests').classList.toggle('d-none',  _currentTab !== 'requests');
    document.getElementById('tabSent').classList.toggle('d-none',      _currentTab !== 'sent');
  });
});

// ── Helpers ───────────────────────────────────────────────────────────────────

function initials(detail) {
  const name = detail?.display_name || detail?.username || '?';
  return name.slice(0, 2).toUpperCase();
}

function displayName(detail) {
  return esc(detail?.display_name || detail?.username || '—');
}

// ── Friends ───────────────────────────────────────────────────────────────────

async function loadFriends() {
  try {
    const data = await apiGet('/social/friends/');
    const grid = document.getElementById('friendsGrid');
    const count = document.getElementById('friendsCount');
    count.textContent = data.length;

    if (!data.length) {
      grid.innerHTML = '<div class="col-12 text-center text-muted py-5"><i class="bi bi-people" style="font-size:2.5rem;opacity:.2;"></i><p class="mt-2 mb-0">No friends yet. Use "Add friend" to get started.</p></div>';
      return;
    }

    // We need to know which side is "us" — resolved via unread-count trick:
    // actually we can figure it out since from_user or to_user is the current user.
    // But we don't have current user id here. Let's show both sides gracefully.
    grid.innerHTML = data.map(f => {
      // Show the "other" person — API returns both sides; we show both names
      const fromD = f.from_user_detail;
      const toD   = f.to_user_detail;
      return `
        <div class="col-sm-6 col-md-4 col-lg-3">
          <div class="card border-0 shadow-sm friend-card h-100">
            <div class="card-body d-flex flex-column gap-2">
              <div class="d-flex align-items-center gap-3">
                <div class="avatar-lg">${initials(fromD)}</div>
                <div class="overflow-hidden">
                  <div class="fw-semibold text-truncate">${displayName(fromD)}</div>
                  <div class="text-muted small">@${esc(fromD?.username || '—')}</div>
                </div>
              </div>
              <div class="d-flex align-items-center gap-3">
                <div class="avatar-lg" style="background:#e8f5e9;color:#2e7d32;">${initials(toD)}</div>
                <div class="overflow-hidden">
                  <div class="fw-semibold text-truncate">${displayName(toD)}</div>
                  <div class="text-muted small">@${esc(toD?.username || '—')}</div>
                </div>
              </div>
              <div class="mt-auto d-flex gap-2">
                <button class="btn btn-sm btn-outline-danger flex-grow-1"
                        onclick="unfriend(${f.id})">
                  <i class="bi bi-person-dash me-1"></i>Unfriend
                </button>
                <a class="btn btn-sm btn-outline-primary" href="/messages.html"
                   title="Send message"><i class="bi bi-envelope"></i></a>
              </div>
            </div>
          </div>
        </div>`;
    }).join('');
  } catch (e) {
    document.getElementById('friendsGrid').innerHTML =
      '<div class="col-12 text-danger text-center py-3 small">Failed to load friends.</div>';
  }
}

async function unfriend(id) {
  if (!confirm('Remove this friendship?')) return;
  try {
    await apiDelete(`/social/friends/${id}/`);
    showToast('Friendship removed.');
    loadFriends();
  } catch (e) {
    showToast('Failed to remove friendship.', 'danger');
  }
}

// ── Incoming requests ─────────────────────────────────────────────────────────

async function loadRequests() {
  try {
    const data  = await apiGet('/social/friends/requests/');
    const el    = document.getElementById('requestsList');
    const badge = document.getElementById('requestsCount');

    if (data.length > 0) {
      badge.textContent = data.length;
      badge.classList.remove('d-none');
    } else {
      badge.classList.add('d-none');
    }

    if (!data.length) {
      el.innerHTML = '<div class="text-center text-muted py-5"><p class="mb-0">No pending requests.</p></div>';
      return;
    }

    el.innerHTML = data.map(f => `
      <div class="req-card d-flex align-items-center gap-3 mb-2" id="req-${f.id}">
        <div class="avatar-lg">${initials(f.from_user_detail)}</div>
        <div class="flex-grow-1 overflow-hidden">
          <div class="fw-semibold text-truncate">${displayName(f.from_user_detail)}</div>
          <div class="text-muted small">@${esc(f.from_user_detail?.username || '—')}</div>
        </div>
        <div class="d-flex gap-2 flex-shrink-0">
          <button class="btn btn-sm btn-success" onclick="acceptRequest(${f.id})">
            <i class="bi bi-check-lg"></i> Accept
          </button>
          <button class="btn btn-sm btn-outline-danger" onclick="declineRequest(${f.id})">
            <i class="bi bi-x-lg"></i>
          </button>
        </div>
      </div>`
    ).join('');
  } catch (e) {
    document.getElementById('requestsList').innerHTML =
      '<div class="text-danger text-center py-3 small">Failed to load requests.</div>';
  }
}

async function acceptRequest(id) {
  try {
    await apiPost(`/social/friends/${id}/accept/`, {});
    showToast('Friend request accepted!');
    document.getElementById(`req-${id}`)?.remove();
    loadFriends();
    loadRequests();
  } catch (e) {
    showToast('Failed to accept request.', 'danger');
  }
}

async function declineRequest(id) {
  try {
    await apiPost(`/social/friends/${id}/decline/`, {});
    showToast('Request declined.');
    document.getElementById(`req-${id}`)?.remove();
    loadRequests();
  } catch (e) {
    showToast('Failed to decline request.', 'danger');
  }
}

// ── Sent requests ─────────────────────────────────────────────────────────────

async function loadSentRequests() {
  try {
    const data  = await apiGet('/social/friends/sent-requests/');
    const el    = document.getElementById('sentList');
    const badge = document.getElementById('sentCount');

    if (data.length > 0) {
      badge.textContent = data.length;
      badge.classList.remove('d-none');
    } else {
      badge.classList.add('d-none');
    }

    if (!data.length) {
      el.innerHTML = '<div class="text-center text-muted py-5"><p class="mb-0">No sent requests.</p></div>';
      return;
    }

    el.innerHTML = data.map(f => `
      <div class="req-card d-flex align-items-center gap-3 mb-2" id="sent-${f.id}">
        <div class="avatar-lg" style="background:#fff3cd;color:#856404;">${initials(f.to_user_detail)}</div>
        <div class="flex-grow-1 overflow-hidden">
          <div class="fw-semibold text-truncate">${displayName(f.to_user_detail)}</div>
          <div class="text-muted small">@${esc(f.to_user_detail?.username || '—')}</div>
        </div>
        <span class="badge bg-warning text-dark me-2">Pending</span>
        <button class="btn btn-sm btn-outline-secondary" onclick="cancelRequest(${f.id})">
          Cancel
        </button>
      </div>`
    ).join('');
  } catch (e) {
    document.getElementById('sentList').innerHTML =
      '<div class="text-danger text-center py-3 small">Failed to load sent requests.</div>';
  }
}

async function cancelRequest(id) {
  if (!confirm('Cancel this friend request?')) return;
  try {
    await apiPost(`/social/friends/${id}/decline/`, {});
    showToast('Request cancelled.');
    document.getElementById(`sent-${id}`)?.remove();
    loadSentRequests();
  } catch (e) {
    showToast('Failed to cancel request.', 'danger');
  }
}

// ── Add friend modal ──────────────────────────────────────────────────────────

document.getElementById('addFriendBtn').addEventListener('click', () => {
  document.getElementById('friendSearch').value = '';
  document.getElementById('friendSearchResults').innerHTML = '';
  document.getElementById('addAlert').classList.add('d-none');
  addFriendModal.show();
  setTimeout(() => document.getElementById('friendSearch').focus(), 300);
});

let _friendSearchTimer = null;
document.getElementById('friendSearch').addEventListener('input', function () {
  clearTimeout(_friendSearchTimer);
  const q = this.value.trim();
  const resultsEl = document.getElementById('friendSearchResults');
  if (q.length < 2) { resultsEl.innerHTML = ''; return; }

  _friendSearchTimer = setTimeout(async () => {
    try {
      const results = await apiGet(`/social/members/?q=${encodeURIComponent(q)}`);
      if (!results.length) {
        resultsEl.innerHTML = '<div class="list-group-item text-muted small">No users found.</div>';
        return;
      }
      resultsEl.innerHTML = results.map(u => `
        <div class="list-group-item list-group-item-action d-flex align-items-center justify-content-between py-2">
          <div>
            <strong>${esc(u.display_name || u.username)}</strong>
            <span class="text-muted ms-1 small">@${esc(u.username)}</span>
          </div>
          <button class="btn btn-sm btn-primary" onclick="sendRequest(${u.id}, this)">
            <i class="bi bi-person-plus-fill me-1"></i>Add
          </button>
        </div>`
      ).join('');
    } catch (e) { /* ignore */ }
  }, 300);
});

async function sendRequest(userId, btn) {
  const alertEl = document.getElementById('addAlert');
  alertEl.classList.add('d-none');
  btn.disabled = true;
  btn.innerHTML = '<span class="spinner-border spinner-border-sm"></span>';
  try {
    await apiPost('/social/friends/', { to_user: userId });
    btn.outerHTML = '<span class="badge bg-success">Request sent</span>';
    showToast('Friend request sent!');
    loadSentRequests();
  } catch (e) {
    if (e.status === 409) {
      btn.outerHTML = '<span class="badge bg-secondary">Already connected</span>';
    } else {
      alertEl.textContent = 'Failed to send request.';
      alertEl.classList.remove('d-none');
      btn.disabled = false;
      btn.innerHTML = '<i class="bi bi-person-plus-fill me-1"></i>Add';
    }
  }
}

// ── Boot ──────────────────────────────────────────────────────────────────────

loadFriends();
loadRequests();
loadSentRequests();