(function() {
  var C = window.ExplorerCommon;

  var state = {
    currentAddress: '',
    currentPubKey:  '',
    nextOffset:     0,
    hasMore:        false,
    limit:          50
  };

  /* ── Helpers ─────────────────────────────────────────────────────────────── */

  function linkAddress(value, label) {
    return '<a href="/address?address=' + encodeURIComponent(value) + '">' +
           C.esc(label || C.shortAddress(value)) + '</a>';
  }

  function direction(tx, pubKey) {
    if (tx.type === 'BLOCK_REWARD' || tx.type === 'HEARTBEAT') return { cls: 'recv', arrow: '↓' };
    if (tx.type === 'RELAY_PROOF')  return { cls: 'recv', arrow: '↓' };
    if (tx.from === pubKey && (!tx.to || tx.to !== pubKey)) return { cls: 'sent', arrow: '↑' };
    if (tx.to   === pubKey && tx.from !== pubKey)           return { cls: 'recv', arrow: '↓' };
    return { cls: 'neutral', arrow: '·' };
  }

  /* ── Badge builder ───────────────────────────────────────────────────────── */

  function badge(text, variant) {
    return '<span class="addr-badge addr-badge-' + variant + '">' + C.esc(text) + '</span>';
  }

  /* ── Profile render ──────────────────────────────────────────────────────── */

  function renderProfile(addrData, identData, nodeData) {
    var pubKey  = addrData.pub_key  || '';
    var address = addrData.address  || '';

    state.currentPubKey = pubKey;

    // Avatar initials (first letter of nickname or first char of address)
    var name = (identData && identData.nickname) || '';
    var avatarChar = name ? name[0].toUpperCase() : (address ? address[2] || '◆' : '◆');
    document.getElementById('addrAvatar').textContent = avatarChar;

    // Name
    document.getElementById('addrNickname').textContent = name || 'Unknown Wallet';

    // Badges
    var badges = '';
    if (identData && identData.registered) badges += badge('Registered', 'ok');
    if (nodeData  && nodeData.blocks_produced > 0) badges += badge('Validator', 'accent');
    if (nodeData  && nodeData.relay_proofs > 0)    badges += badge('Relay Node', 'relay');
    document.getElementById('addrBadges').innerHTML = badges || badge('Unregistered', 'muted');

    // Balance
    document.getElementById('walletBalance').textContent   = addrData.balance || C.toToken(addrData.balance_ut);
    document.getElementById('walletBalanceSub').textContent = addrData.balance_ut != null
      ? addrData.balance_ut + ' µT' : '';

    // Address field
    document.getElementById('walletAddress').textContent = address;
    document.getElementById('walletAddress').title       = address;

    // Public key field
    document.getElementById('walletPubKey').textContent = pubKey;
    document.getElementById('walletPubKey').title       = pubKey;

    // X25519 key
    if (identData && identData.x25519_pub) {
      document.getElementById('walletX25519').textContent = identData.x25519_pub;
      document.getElementById('walletX25519').title       = identData.x25519_pub;
      document.getElementById('x25519Row').style.display  = '';
    } else {
      document.getElementById('x25519Row').style.display = 'none';
    }

    // Node page link (if address is a node itself)
    if (nodeData && (nodeData.blocks_produced > 0 || nodeData.relay_proofs > 0 || nodeData.heartbeats > 0)) {
      var nodeLink = document.getElementById('nodePageLink');
      nodeLink.href = '/node?node=' + encodeURIComponent(pubKey);
      document.getElementById('nodeLinkRow').style.display = '';
    } else {
      document.getElementById('nodeLinkRow').style.display = 'none';
    }

    // Bound wallet (only for pure node addresses)
    if (nodeData && nodeData.wallet_binding_address && nodeData.wallet_binding_address !== address) {
      var wbl = document.getElementById('walletBindingLink');
      wbl.href = '/address?address=' + encodeURIComponent(nodeData.wallet_binding_address);
      wbl.textContent = nodeData.wallet_binding_address;
      document.getElementById('walletBindingRow').style.display = '';
    } else {
      document.getElementById('walletBindingRow').style.display = 'none';
    }

    // Node stats panel
    if (nodeData && (nodeData.blocks_produced > 0 || nodeData.relay_proofs > 0 || nodeData.heartbeats > 0)) {
      document.getElementById('nodeBlocks').textContent      = nodeData.blocks_produced  || 0;
      document.getElementById('nodeRelayProofs').textContent = nodeData.relay_proofs     || 0;
      document.getElementById('nodeRepScore').textContent    = nodeData.reputation_score || 0;
      document.getElementById('nodeRepRank').textContent     = nodeData.reputation_rank  || '—';
      document.getElementById('nodeHeartbeats').textContent  = nodeData.heartbeats       || 0;
      document.getElementById('nodeSlashes').textContent     = nodeData.slash_count      || 0;
      document.getElementById('nodeRecentRewards').textContent = nodeData.recent_rewards || '—';
      var window_ = nodeData.recent_window_blocks || 0;
      var produced = nodeData.recent_blocks_produced || 0;
      document.getElementById('nodeRecentWindow').textContent =
        'last ' + window_ + ' blocks, produced ' + produced;
      document.getElementById('nodeStatsPanel').style.display = '';
    } else {
      document.getElementById('nodeStatsPanel').style.display = 'none';
    }
  }

  /* ── Transaction row builder ─────────────────────────────────────────────── */

  function txTypeIcon(type) {
    var icons = {
      TRANSFER:       'arrow-left-right',
      REGISTER_KEY:   'user-check',
      RELAY_PROOF:    'zap',
      HEARTBEAT:      'activity',
      BLOCK_REWARD:   'layers-3',
      BIND_WALLET:    'link',
      REGISTER_RELAY: 'radio',
      SLASH:          'alert-triangle',
      ADD_VALIDATOR:  'shield-plus',
      REMOVE_VALIDATOR: 'shield-minus',
    };
    return icons[type] || 'circle';
  }

  function appendTxRows(txs) {
    var body = document.getElementById('walletTxBody');
    for (var i = 0; i < txs.length; i++) {
      var tx  = txs[i];
      var dir = direction(tx, state.currentPubKey);

      var fromAddr  = tx.from_addr || (tx.from ? C.shortAddress(tx.from) : '—');
      var toAddr    = tx.to_addr   || (tx.to   ? C.shortAddress(tx.to)   : '—');
      var fromCell  = tx.from ? linkAddress(tx.from, tx.from_addr || C.shortAddress(tx.from)) : '<span class="text-muted">—</span>';
      var toCell    = tx.to   ? linkAddress(tx.to,   tx.to_addr   || C.shortAddress(tx.to))   : '<span class="text-muted">—</span>';

      var amount    = Number(tx.amount_ut || 0);
      var amountStr = amount > 0 ? C.toToken(amount) : '—';
      var amountCls = dir.cls === 'recv' ? 'pos' : (dir.cls === 'sent' ? 'neg' : 'neutral');
      var amountSign = dir.cls === 'recv' ? '+' : (dir.cls === 'sent' ? '−' : '');

      var memo = tx.memo ? C.esc(tx.memo) : '';
      var blockRef = tx.block_index != null
        ? '<span class="tx-block-ref">block #' + tx.block_index + '</span>'
        : '';

      var tr = document.createElement('tr');
      tr.className = 'tx-row';
      tr.dataset.txid = tx.id || '';
      tr.innerHTML =
        '<td title="' + C.esc(C.fmtTime(tx.time)) + '">' +
          '<div class="tx-time">' + C.esc(C.timeAgo(tx.time)) + '</div>' +
        '</td>' +
        '<td>' +
          '<div class="tx-type-cell">' +
            '<span class="tx-type-icon tx-icon-' + C.esc(dir.cls) + '">' +
              '<i data-lucide="' + txTypeIcon(tx.type) + '"></i>' +
            '</span>' +
            '<div>' +
              '<div class="tx-type-name">' + C.esc(C.txLabel(tx.type)) + '</div>' +
              '<div class="tx-type-raw">' + C.esc(tx.type || '') + '</div>' +
            '</div>' +
          '</div>' +
        '</td>' +
        '<td>' +
          '<div class="tx-route">' +
            '<span class="tx-route-item">' + fromCell + '</span>' +
            '<i data-lucide="arrow-right" class="tx-route-arrow"></i>' +
            '<span class="tx-route-item">' + toCell + '</span>' +
          '</div>' +
        '</td>' +
        '<td>' +
          (memo ? '<div class="tx-memo-block">' + memo + '</div>' : '') +
          blockRef +
        '</td>' +
        '<td style="text-align:right">' +
          '<div class="tx-amount ' + amountCls + '">' + amountSign + C.esc(amountStr) + '</div>' +
          (tx.fee_ut ? '<div class="tx-fee">fee ' + C.esc(C.toToken(tx.fee_ut)) + '</div>' : '') +
        '</td>';
      body.appendChild(tr);
    }
    C.refreshIcons();
  }

  /* ── Load wallet ─────────────────────────────────────────────────────────── */

  function showEmpty() {
    var es = document.getElementById('emptyState');
    var mc = document.getElementById('mainContent');
    if (es) es.style.display = '';
    if (mc) mc.style.display = 'none';
  }

  function showError(msg) {
    var es  = document.getElementById('emptyState');
    var mc  = document.getElementById('mainContent');
    var eb  = document.getElementById('errorBanner');
    var em  = document.getElementById('errorMsg');
    var ps  = document.getElementById('profileSection');
    if (es) es.style.display = 'none';
    if (eb) { eb.style.display = ''; if (em) em.textContent = msg; }
    if (ps) ps.style.display = 'none';
    if (mc) mc.style.display = '';
    C.refreshIcons();
  }

  async function loadWallet(address) {
    if (!address) return;
    state.currentAddress = address;
    state.nextOffset     = 0;
    state.hasMore        = false;

    // Hide empty state, hide main, show loading
    var es = document.getElementById('emptyState');
    if (es) es.style.display = 'none';
    document.getElementById('mainContent').style.display = 'none';
    document.getElementById('errorBanner').style.display = 'none';
    document.getElementById('profileSection').style.display = '';
    document.getElementById('walletTxBody').innerHTML    = '';
    document.getElementById('walletTxCount').textContent = '';
    C.setStatus('Loading…', 'warn');

    try {
      // Parallel fetch: address data + identity + node info
      var results = await Promise.all([
        C.fetchJSON('/api/address/' + encodeURIComponent(address) +
                    '?limit=' + state.limit + '&offset=0'),
        C.fetchJSON('/api/identity/' + encodeURIComponent(address)).catch(function() { return null; }),
        C.fetchJSON('/api/node/'     + encodeURIComponent(address)).catch(function() { return null; }),
        C.fetchJSON('/api/tokens').catch(function() { return null; }),
        C.fetchJSON('/api/nfts/owner/' + encodeURIComponent(address)).catch(function() { return null; }),
      ]);
      var addrData  = results[0];
      var identData = results[1];
      var nodeData  = results[2];
      var tokensAll = results[3];
      var nftsOwned = results[4];

      renderProfile(addrData, identData, nodeData);

      // ── Token balances ──────────────────────────────────────────────────
      var pubKey = addrData.pub_key || address;
      var allTokens = (tokensAll && Array.isArray(tokensAll.tokens)) ? tokensAll.tokens : [];
      if (allTokens.length) {
        var balFetches = allTokens.map(function(t) {
          return C.fetchJSON('/api/tokens/' + t.token_id + '/balance/' + encodeURIComponent(pubKey))
            .then(function(b) { return { token: t, balance: b && b.balance != null ? b.balance : 0 }; })
            .catch(function() { return { token: t, balance: 0 }; });
        });
        var balResults = await Promise.all(balFetches);
        var nonZero = balResults.filter(function(r) { return r.balance > 0; });
        if (nonZero.length) {
          var rows = '';
          nonZero.forEach(function(r) {
            var t = r.token;
            var d = t.decimals || 0;
            var sup = r.balance;
            var whole = d > 0 ? Math.floor(sup / Math.pow(10, d)) : sup;
            var frac  = d > 0 ? sup % Math.pow(10, d) : 0;
            var balFmt = whole.toLocaleString() +
              (frac > 0 ? '.' + String(frac).padStart(d, '0').replace(/0+$/, '') : '');
            rows += '<tr>' +
              '<td><a href="/token?id=' + encodeURIComponent(t.token_id) + '" class="token-sym">' + C.esc(t.symbol) + '</a></td>' +
              '<td>' + C.esc(t.name) + '</td>' +
              '<td style="text-align:right" class="mono">' + C.esc(balFmt) + '</td>' +
              '<td><a href="/token?id=' + encodeURIComponent(t.token_id) + '" class="pill-link" style="font-size:12px;padding:4px 10px">Details</a></td>' +
              '</tr>';
          });
          document.getElementById('tokenBalBody').innerHTML = rows;
          document.getElementById('tokenBalPanel').style.display = '';
        }
      }

      // ── NFTs owned ──────────────────────────────────────────────────────
      var ownedNFTs = (nftsOwned && Array.isArray(nftsOwned.nfts)) ? nftsOwned.nfts : [];
      if (ownedNFTs.length) {
        document.getElementById('nftOwnedCount').textContent = ownedNFTs.length + ' NFT' + (ownedNFTs.length !== 1 ? 's' : '');
        var cards = '';
        ownedNFTs.forEach(function(n) {
          var imgHtml = (n.uri && /\.(png|jpg|jpeg|gif|svg|webp)/i.test(n.uri))
            ? '<img class="nft-card-img" src="' + C.esc(n.uri) + '" alt="" loading="lazy">'
            : '<div class="nft-card-img nft-card-placeholder"><i data-lucide="image"></i></div>';
          cards += '<a class="nft-card" href="/token?nft=' + encodeURIComponent(n.nft_id) + '">' +
            imgHtml +
            '<div class="nft-card-body">' +
              '<div class="nft-card-name">' + C.esc(n.name) + '</div>' +
              '<div class="nft-card-id mono">' + C.short(n.nft_id, 16) + '</div>' +
            '</div>' +
            '</a>';
        });
        document.getElementById('addrNFTGrid').innerHTML = cards;
        document.getElementById('nftPanel').style.display = '';
      }

      var txs = addrData.transactions || [];
      if (!txs.length) {
        document.getElementById('walletTxBody').innerHTML =
          '<tr><td colspan="5" class="tbl-empty">No transactions for this wallet.</td></tr>';
      } else {
        appendTxRows(txs);
      }

      state.nextOffset = addrData.next_offset || txs.length;
      state.hasMore    = !!addrData.has_more;
      setLoadMoreVisible(state.hasMore);

      var countText = txs.length + (state.hasMore ? '+' : '') + ' transaction' +
                      (txs.length !== 1 ? 's' : '');
      document.getElementById('walletTxCount').textContent = countText;

      // Update page title and URL
      var displayName = (identData && identData.nickname) || addrData.address || address;
      document.title = displayName + ' | DChain Explorer';
      window.history.replaceState({}, '',
        '/address?address=' + encodeURIComponent(addrData.pub_key || address));

      document.getElementById('mainContent').style.display = '';
      C.setStatus('', '');
      C.refreshIcons();

    } catch (e) {
      showError(e.message || 'Unknown error');
      C.setStatus('', '');
    }
  }

  async function loadMore() {
    if (!state.currentAddress || !state.hasMore) return;
    C.setStatus('Loading more…', 'warn');
    setLoadMoreVisible(false);
    try {
      var data = await C.fetchJSON('/api/address/' + encodeURIComponent(state.currentAddress) +
        '?limit=' + state.limit + '&offset=' + state.nextOffset);
      var txs = data.transactions || [];
      appendTxRows(txs);
      state.nextOffset = data.next_offset || (state.nextOffset + txs.length);
      state.hasMore    = !!data.has_more;

      var prev = parseInt((document.getElementById('walletTxCount').textContent || '0'), 10) || 0;
      var total = prev + txs.length;
      document.getElementById('walletTxCount').textContent =
        total + (state.hasMore ? '+' : '') + ' transactions';
      setLoadMoreVisible(state.hasMore);
      C.setStatus('', '');
    } catch (e) {
      C.setStatus('Load failed: ' + e.message, 'err');
      setLoadMoreVisible(true);
    }
  }

  function setLoadMoreVisible(v) {
    var btn = document.getElementById('loadMoreBtn');
    if (btn) btn.style.display = v ? '' : 'none';
  }

  /* ── Copy buttons ────────────────────────────────────────────────────────── */

  document.addEventListener('click', function(e) {
    var t = e.target;
    if (!t) return;

    // Copy button
    var btn = t.closest ? t.closest('.copy-btn') : null;
    if (btn) {
      var src = document.getElementById(btn.dataset.copyId);
      if (src) {
        navigator.clipboard.writeText(src.textContent || src.title || '').catch(function() {});
        btn.classList.add('copy-btn-done');
        setTimeout(function() { btn.classList.remove('copy-btn-done'); }, 1200);
      }
      return;
    }

    // TX row click → tx detail page
    var link = t.closest ? t.closest('a') : null;
    if (link) return;
    var row = t.closest ? t.closest('tr.tx-row') : null;
    if (row && row.dataset && row.dataset.txid) {
      window.location.href = '/tx?id=' + encodeURIComponent(row.dataset.txid);
    }
  });

  /* ── Event wiring ────────────────────────────────────────────────────────── */

  document.getElementById('addressBtn').addEventListener('click', function() {
    var val = (document.getElementById('addressInput').value || '').trim();
    if (val) loadWallet(val);
  });

  document.getElementById('addressInput').addEventListener('keydown', function(e) {
    if (e.key === 'Enter') document.getElementById('addressBtn').click();
  });

  document.getElementById('loadMoreBtn').addEventListener('click', loadMore);

  /* ── Auto-load from URL param ────────────────────────────────────────────── */

  var initial = C.q('address');
  if (initial) {
    document.getElementById('addressInput').value = initial;
    loadWallet(initial);
  } else {
    showEmpty();
  }

})();