// Wallet plumbing: EIP-1193 connect, chain add/switch, SIWE sign-in, and raw
// calldata builders for the contract's tx functions (no library needed).
window.IAPWallet = (function () {
  const SEL_BUY = '0xfd095e97';      // buy(uint32,uint32)
  const SEL_ACTIVATE = '0x1a93ec95'; // activate(uint32)
  const pad = v => BigInt(v).toString(16).padStart(64, '0');

  // ── multi-wallet: EIP-6963 discovery + a picker; falls back to window.ethereum.
  //    Supports Trust, MetaMask, SafePal, Phantom, OKX, TokenPocket and any 6963 wallet.
  const discovered = [];
  try {
    window.addEventListener('eip6963:announceProvider', e => {
      const d = e.detail;
      if (d && d.provider && !discovered.some(x => x.info && d.info && x.info.uuid === d.info.uuid)) discovered.push(d);
    });
    window.dispatchEvent(new Event('eip6963:requestProvider'));
  } catch (e) {}
  let CHOSEN = null;
  function providerList() {
    const seen = new Set(), out = [];
    for (const d of discovered) { const k = (d.info && (d.info.rdns || d.info.uuid)) || Math.random(); if (!seen.has(k)) { seen.add(k); out.push(d); } }
    const add = (p, name) => { if (p && !out.some(x => x.provider === p)) out.push({ info: { name }, provider: p }); };
    if (window.ethereum) {
      if (Array.isArray(window.ethereum.providers)) window.ethereum.providers.forEach(p => add(p, p.isMetaMask ? 'MetaMask' : p.isTrust || p.isTrustWallet ? 'Trust Wallet' : 'Injected wallet'));
      else add(window.ethereum, window.ethereum.isMetaMask ? 'MetaMask' : window.ethereum.isTrust || window.ethereum.isTrustWallet ? 'Trust Wallet' : 'Injected wallet');
    }
    try { add(window.phantom && window.phantom.ethereum, 'Phantom'); } catch (e) {}
    add(window.okxwallet, 'OKX Wallet');
    try { add(window.tokenpocket && window.tokenpocket.ethereum, 'TokenPocket'); } catch (e) {}
    add(window.safepal, 'SafePal');
    return out;
  }
  function pickModal(list) {
    return new Promise(resolve => {
      const back = document.createElement('div');
      back.style.cssText = 'position:fixed;inset:0;z-index:200;display:grid;place-items:center;background:rgba(2,10,8,.72)';
      const card = document.createElement('div');
      card.style.cssText = 'background:var(--panel-solid,#0b1512);border:1px solid var(--line-strong,#2c5044);border-radius:16px;padding:20px;max-width:360px;width:92%';
      card.innerHTML = '<h3 style="margin:0 0 12px">Choose your wallet</h3>';
      const close = v => { if (back.parentNode) document.body.removeChild(back); resolve(v); };
      list.forEach(d => {
        const b = document.createElement('button');
        b.className = 'btn sec'; b.type = 'button';
        b.style.cssText = 'display:flex;align-items:center;gap:10px;width:100%;justify-content:flex-start;margin:6px 0';
        b.innerHTML = (d.info && d.info.icon ? '<img src="' + d.info.icon + '" alt="" width="22" height="22" style="border-radius:5px">' : '') + '<span>' + ((d.info && d.info.name) || 'Wallet') + '</span>';
        b.addEventListener('click', () => close(d));
        card.appendChild(b);
      });
      const cancel = document.createElement('button');
      cancel.className = 'btn sec small'; cancel.type = 'button'; cancel.textContent = 'Cancel'; cancel.style.marginTop = '10px';
      cancel.addEventListener('click', () => close(null));
      card.appendChild(cancel); back.appendChild(card); document.body.appendChild(back);
    });
  }
  // ── WalletConnect: works in any normal mobile browser (no in-app dApp browser
  //    needed) and on desktop via QR. Lazy-loaded UMD; the returned object is a
  //    plain EIP-1193 provider, so everything downstream is unchanged.
  let wcSdkPromise = null, wcProvider = null;
  function loadWcSdk() {
    const ready = () => (window['@walletconnect/ethereum-provider'] || {}).EthereumProvider;
    if (ready()) return Promise.resolve(ready());
    if (wcSdkPromise) return wcSdkPromise;
    wcSdkPromise = new Promise((resolve, reject) => {
      const s = document.createElement('script');
      s.src = 'https://cdn.jsdelivr.net/npm/@walletconnect/ethereum-provider@2.21.1/dist/index.umd.js';
      s.async = true;
      s.onload = () => { const EP = ready(); EP ? resolve(EP) : reject(new Error('WalletConnect failed to load.')); };
      s.onerror = () => reject(new Error('Could not load WalletConnect. Check your connection and try again.'));
      document.head.appendChild(s);
    });
    return wcSdkPromise;
  }
  async function makeWalletConnect(c) {
    const projectId = String(c.walletConnectProjectId || '').trim();
    if (!projectId) throw new Error('WalletConnect is not configured yet.');
    const EP = await loadWcSdk();
    const chainId = Number(c.chainId);
    if (!wcProvider) {
      // optionalChains (not required): testnet wallets like Trust hang or reject
      // a session that REQUIRES a chain they don't natively list (Amoy 80002).
      // Optional lets the session establish; we switch/add the chain after.
      wcProvider = await EP.init({
        projectId, optionalChains: [chainId], showQrModal: true,
        rpcMap: { [chainId]: c.rpc },
        metadata: { name: c.siteName || 'InstantAdPay', description: c.tagline || 'Advertise and earn, paid on-chain.',
          url: location.origin, icons: [location.origin + '/logo-icon.png'],
          // ask the wallet to bounce back to the dashboard after each approval
          redirect: { native: '', universal: location.origin + '/my' } }
      });
    }
    // WalletConnect remembers the last wallet and auto-deep-links to it, which
    // traps users on a wallet that won't finish (e.g. Trust on a testnet). Clear
    // that choice so the picker ("All Wallets") shows every time.
    try { localStorage.removeItem('WALLETCONNECT_DEEPLINK_CHOICE'); } catch (e) {}
    if (!wcProvider.session) await wcProvider.connect(); // QR on desktop, opens the wallet app on mobile
    return wcProvider;
  }
  async function ensureProvider() {
    if (CHOSEN && CHOSEN.provider) return CHOSEN.provider;
    const list = providerList();
    let cfg = null;
    try { cfg = await IAP.getConfig(); } catch (e) {}
    // WalletConnect only works on chains external wallets recognize (Polygon
    // mainnet 137 / Amoy testnet 80002). On the private rehearsal chain (31337)
    // wallets reject the session ("user rejected"), so we keep to the injected
    // path there and light WC up automatically once we're on a public chain.
    const WC_CHAINS = [137, 80002];
    const wcOn = !!(cfg && String(cfg.walletConnectProjectId || '').trim() && WC_CHAINS.includes(Number(cfg.chainId)));
    if (wcOn) list.push({ info: { name: 'WalletConnect — scan a QR or open your wallet app', __wc: true } });
    if (!list.length) throw new Error('No wallet found. Open this page in your wallet app (Trust, MetaMask, SafePal, Phantom, OKX, TokenPocket) or install a wallet extension.');
    const pick = list.length === 1 ? list[0] : await pickModal(list);
    if (!pick) throw new Error('No wallet selected.');
    CHOSEN = (pick.info && pick.info.__wc) ? { info: pick.info, provider: await makeWalletConnect(cfg) } : pick;
    return CHOSEN.provider;
  }
  function eth() {
    if (CHOSEN && CHOSEN.provider) return CHOSEN.provider;
    if (window.ethereum) return window.ethereum;
    throw new Error('No wallet found. Open this page in your wallet app or install a wallet extension.');
  }
  async function ensureChain(c) {
    const want = '0x' + Number(c.chainId).toString(16);
    const cur = await eth().request({ method: 'eth_chainId' });
    if (cur === want) return;
    try {
      await eth().request({ method: 'wallet_switchEthereumChain', params: [{ chainId: want }] });
    } catch (e) {
      if (e.code !== 4902) throw e;
      const addParams = {
        chainId: want, chainName: c.chainName, nativeCurrency: { name: 'POL', symbol: 'POL', decimals: 18 },
        rpcUrls: [c.rpc] };
      // only include a block explorer when it's a real URL — an empty string here
      // makes wallets (Trust Wallet especially) reject with "invalid method parameters"
      if (c.explorer && /^https?:\/\//i.test(c.explorer)) addParams.blockExplorerUrls = [c.explorer];
      await eth().request({ method: 'wallet_addEthereumChain', params: [addParams] });
    }
  }
  async function connect() {
    const c = await IAP.getConfig();
    await ensureProvider();
    const [addr] = await eth().request({ method: 'eth_requestAccounts' });
    await ensureChain(c);
    return addr;
  }
  // SIWE: challenge -> personal_sign -> verify (server sets the session cookie)
  async function signIn() {
    const addr = await connect();
    const ch = await (await fetch('/api/auth/challenge', { method: 'POST',
      headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ address: addr }) })).json();
    if (ch.error) throw new Error(ch.error);
    // hex-encode the message: MetaMask accepts a raw string, but Trust Wallet and
    // others require hex for personal_sign (else "invalid method parameters").
    // The signed bytes are identical, so server-side recovery is unchanged.
    const hexMsg = '0x' + Array.from(new TextEncoder().encode(ch.message)).map(b => b.toString(16).padStart(2, '0')).join('');
    const sig = await eth().request({ method: 'personal_sign', params: [hexMsg, addr] });
    const r = await (await fetch('/api/auth/verify', { method: 'POST',
      headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ address: addr, signature: sig }) })).json();
    if (r.error) throw new Error(r.error);
    return r; // {address, memberId, sponsorId}
  }
  async function sendTx(data, valueWei) {
    const c = await IAP.getConfig();
    await ensureProvider();
    const [addr] = await eth().request({ method: 'eth_requestAccounts' });
    await ensureChain(c);
    const tx = { from: addr, to: c.contract, data };
    if (valueWei) tx.value = '0x' + BigInt(valueWei).toString(16);
    // Polygon (mainnet + Amoy) enforce a ~25 gwei minimum priority fee; wallets
    // routinely lowball it and the RPC rejects "gas tip below minimum". Set
    // explicit EIP-1559 fees above the floor, plus a safe gas limit so the wallet
    // doesn't mis-estimate. Unused gas is never charged.
    tx.maxPriorityFeePerGas = '0x' + (30n * 10n ** 9n).toString(16); // 30 gwei (> Polygon's ~25 gwei floor)
    tx.maxFeePerGas = '0x' + (50n * 10n ** 9n).toString(16);         // 50 gwei ceiling (Amoy base fee is ~0; avoids MetaMask "fee too high" alert)
    tx.gas = '0x' + (600000n).toString(16);                          // 600k limit
    return eth().request({ method: 'eth_sendTransaction', params: [tx] });
  }
  async function waitTx(hash) {
    // poll our own server (CSP-friendly); it relays the receipt from the RPC
    for (let i = 0; i < 60; i++) {
      const r = await (await fetch('/api/tx/' + hash)).json();
      if (r.found) return { status: r.status, blockNumber: r.blockNumber };
      await new Promise(res => setTimeout(res, 2500));
    }
    throw new Error('Timed out waiting for the transaction. Check the explorer.');
  }
  // buy: quote is read live server-side; pad 2% for oracle drift, contract
  // refunds every wei of excess in the same transaction.
  async function buy(productId, sponsorId, costWei) {
    const value = BigInt(costWei) + BigInt(costWei) / 50n;
    const data = SEL_BUY + pad(productId) + pad(sponsorId || 0);
    const hash = await sendTx(data, value);
    return { hash, receipt: await waitTx(hash) };
  }
  async function activate(sponsorId) {
    const data = SEL_ACTIVATE + pad(sponsorId || 0);
    const hash = await sendTx(data, null);
    return { hash, receipt: await waitTx(hash) };
  }
  // Drop the WalletConnect session + any stuck pending request, and forget the
  // chosen provider so the next connect re-offers the wallet picker.
  async function disconnect() {
    try { if (wcProvider && wcProvider.disconnect) await wcProvider.disconnect(); } catch (e) {}
    wcProvider = null; CHOSEN = null; wcSdkPromise = null;
    // WalletConnect caches the last-used wallet + session in localStorage; clear
    // it all so the next connect re-opens the picker instead of auto-reconnecting.
    try { Object.keys(localStorage).forEach(k => { if (/wc@2|walletconnect|w3m|wcm|reown|ethereum_provider/i.test(k)) localStorage.removeItem(k); }); } catch (e) {}
  }
  return { connect, signIn, buy, activate, waitTx, disconnect };
})();