const options = { method: "GET", headers: { accept: "application/json" } };
let nextUrl = null;

const transactionHistory = async function (url, address) {
  try {
    if (typeof notify === "function")
      notify("Loading transactions...", "success", 1500);
    const response = await fetch(url, {
      method: "GET",
      headers: { accept: "application/json" },
    });
    const data = await response.json();

    const section = document.getElementById("transactionSection");
    if (section) section.style.display = "block";

    __currentAddress = address;
    __currentUrl = url;
    window.lastUsedUrl = url;

    if (data && data.data) {
      console.log(data.data);

      __currentTxs = data.data;
      // track current per-page from url
      const m = url.match(/limit=(\d+)/);
      if (m) __perPage = parseInt(m[1], 10) || __perPage;
      __renderTransactions();

      if (data.meta && data.meta.fingerprint) {
        __nextUrl = `https://api.trongrid.io/v1/accounts/${address}/transactions?limit=${__perPage}&fingerprint=${encodeURIComponent(
          data.meta.fingerprint
        )}`;
      } else {
        __nextUrl = null;
      }
      __updatePagination();
    }
    return data;
  } catch (e) {
    console.error(e);
    if (typeof __origTransactionHistory === "function") {
      __origTransactionHistory(url, address);
    }
    throw e;
  }
};

function fetchNext(address) {
  if (nextUrl) {
    transactionHistory(nextUrl, address);
  }
}

function truncate(str, len = 12) {
  if (!str) return "";
  return str.length > len ? str.slice(0, 6) + "..." + str.slice(-6) : str;
}

function copyToClipboard(text) {
  navigator.clipboard.writeText(text).then(() => {
    alert("Copied: " + text);
  });
}

// State for filtering and pagination
let __nextUrl = null;
let __prevUrls = [];
let __currentAddress = "";
let __currentTxs = [];
let __currentFilter = "all"; // all | received | sent
let __currentPage = 1;
let __currentUrl = null;
let __perPage = 10;

function __renderTransactions() {
  const list = document.getElementById("txList");
  const legacy = document.getElementById("historyOutput");
  if (!list) {
    if (legacy) legacy.innerHTML = "";
    return;
  }
  list.innerHTML = "";

  const filtered = __currentTxs.filter((tx) => {
    const type = tx.raw_data?.contract?.[0]?.type || "";
    let from = "";
    let to = "";
    if (type === "TransferContract") {
      const v = tx.raw_data.contract[0].parameter.value;
      from = tronWeb.address.fromHex(v.owner_address);
      to = tronWeb.address.fromHex(v.to_address);
    } else if (type === "TriggerSmartContract") {
      const v = tx.raw_data.contract[0].parameter.value;
      from = tronWeb.address.fromHex(v.owner_address);
      const input = (v.data || "").startsWith("0x")
        ? v.data.slice(2)
        : v.data || "";
      const method = input.slice(0, 8).toLowerCase();
      if (method === "a9059cbb" && input.length >= 8 + 64 + 64) {
        const addrSlot = input.slice(8, 8 + 64);
        const evmAddrHex = addrSlot.slice(24);
        const tronHex = "41" + evmAddrHex.toLowerCase();
        to = tronWeb.address.fromHex(tronHex);
      }
    }
    if (__currentFilter === "sent") return from === __currentAddress;
    if (__currentFilter === "received") return to === __currentAddress;
    return true;
  });

  if (filtered.length === 0) {
    list.innerHTML =
      '<div class="no-transactions"><i class="fas fa-inbox"></i>No transactions found</div>';
    return;
  }

  filtered.forEach((tx) => {
    const hash = tx.txID;
    const block = tx.blockNumber;
    const age = new Date(tx.block_timestamp).toLocaleString();
    const type = tx.raw_data.contract[0].type;

    let from = "";
    let to = "";
    let amountText = "";
    let directionClass = "";
    let icon = "fa-arrow-up";

    if (type === "TransferContract") {
      const v = tx.raw_data.contract[0].parameter.value;
      from = tronWeb.address.fromHex(v.owner_address);
      to = tronWeb.address.fromHex(v.to_address);
      const amount = v.amount / 1e6;
      amountText = amount + " TRX";
    } else if (type === "TriggerSmartContract") {
      const v = tx.raw_data.contract[0].parameter.value;
      from = tronWeb.address.fromHex(v.owner_address);
      const input = (v.data || "").startsWith("0x")
        ? v.data.slice(2)
        : v.data || "";
      const method = input.slice(0, 8).toLowerCase();
      if (method === "a9059cbb" && input.length >= 8 + 64 + 64) {
        const addrSlot = input.slice(8, 8 + 64);
        const amountSlot = input.slice(8 + 64, 8 + 64 + 64);
        const evmAddrHex = addrSlot.slice(24);
        const tronHex = "41" + evmAddrHex.toLowerCase();
        to = tronWeb.address.fromHex(tronHex);
        const raw = BigInt("0x" + amountSlot);
        amountText = Number(raw) / 1e6 + " USDT";
      }
      icon = "fa-file-signature";
    } else if (
      type === "DelegateResourceContract" ||
      type === "UnDelegateResourceContract"
    ) {
      // Handle resource delegation/undelegation
      const v = tx.raw_data.contract[0].parameter.value;
      from = tronWeb.address.fromHex(v.owner_address);
      to = v.receiver_address
        ? tronWeb.address.fromHex(v.receiver_address)
        : "";
      amountText =
        v.balance / 1e6 +
        " TRX (" +
        (v.resource ? v.resource : "Bandwidth") +
        ")";
      directionClass = "resource";
    }

    // Set direction and icon based on transaction direction
    if (type === "DelegateResourceContract") {
      directionClass = "delegate-resource";
      icon = "fa-exchange-alt"; // custom icon for delegate
    } else if (type === "UnDelegateResourceContract") {
      directionClass = "reclaim-resource";
      icon = "fa-exchange-alt"; // custom icon for undelegate
    } else if (from === __currentAddress) {
      directionClass = "outgoing";
      icon = "fa-arrow-up"; // upward arrow for sent
    } else if (to === __currentAddress) {
      directionClass = "incoming";
      icon = "fa-arrow-down"; // downward arrow for received
    } else {
      directionClass = "";
      icon = "fa-exchange-alt"; // default for other transactions
    }
    const result = tx.ret?.[0]?.contractRet || "UNKNOWN";
    const statusClass = result === "SUCCESS" ? "success" : "failed";

    const card = document.createElement("div");
    card.className = `transaction-card ${directionClass}`;
    card.innerHTML = `
      <div class="tx-main">
        <div class="tx-icon"><i class="fas ${icon}"></i></div>
        <div class="tx-info">
          <div class="tx-header">
            <div>
              <div class="tx-direction">${
                directionClass === "delegate-resource"
                  ? "Delegate Resources"
                  : directionClass === "reclaim-resource"
                  ? "Reclaim Resources"
                  : directionClass === "incoming"
                  ? "Received"
                  : directionClass === "outgoing"
                  ? "Sent"
                  : type
              }</div>
              <div class="tx-date">${age}</div>
            </div>
            <div class="tx-right-info">
              <div class="tx-amount ${
                directionClass === "incoming" ? "incoming" : "outgoing"
              }">${amountText}</div>
              <div class="tx-status ${statusClass}">${result}</div>
            </div>
          </div>
          <div class="tx-addresses">
            <div class="tx-address-row"><span class="address-label">From</span><span class="address-value" 
                onclick="window.open('index.html?page=transactions&address=${from}','_blank')" 
                title="View address details">${from}</span></div>
            <div class="tx-address-row"><span class="address-label">To</span><span class="address-value" 
                onclick="window.open('index.html?page=transactions&address=${to}','_blank')" 
                title="View address details">${to}</span></div>
            <div class="tx-hash"><span class="hash-label">Hash</span><span class="hash-value"><span class="detail-link"
                onclick="window.open('index.html?page=transactions&tx=${hash}','_blank')" 
                title="View transaction details">${hash}</span></span></div>
          </div>
        </div>
      </div>`;
    list.appendChild(card);
  });
}

function __updatePagination() {
  const nextBtn = document.getElementById("nextBtn");
  const prevBtn = document.getElementById("prevBtn");
  const info = document.getElementById("paginationInfo");
  const pageNumbers = document.getElementById("pageNumbers");

  if (nextBtn) nextBtn.disabled = !__nextUrl;
  if (prevBtn) prevBtn.disabled = __prevUrls.length === 0;
  if (info) info.textContent = `Page ${__currentPage} • ${__perPage} / page`;

  if (pageNumbers) {
    pageNumbers.innerHTML = __renderPageNumbers();

    document.querySelectorAll(".page-number").forEach((button) => {
      const pageNum = parseInt(button.textContent);
      if (!isNaN(pageNum)) {
        button.style.cursor = "pointer";
        button.addEventListener("click", () => goToPage(pageNum));
      }
    });
  }
}

function setTransactionFilter(filter) {
  __currentFilter = filter;
  document.querySelectorAll(".filter-btn").forEach((btn) => {
    btn.classList.toggle("active", btn.getAttribute("data-filter") === filter);
  });
  __renderTransactions();
}

function goToNextPage() {
  if (__nextUrl) {
    if (__currentUrl) {
      __prevUrls.push({ url: __currentUrl, page: __currentPage });
    }
    __currentPage += 1;
    transactionHistory(__nextUrl, __currentAddress);
  }
}

function goToPreviousPage() {
  if (__prevUrls.length === 0) return;
  const prev = __prevUrls.pop();
  const prevUrl = prev.url;
  __currentPage = Math.max(1, prev.page || __currentPage - 1);
  if (prevUrl) {
    window.lastUsedUrl = prevUrl;
    transactionHistory(prevUrl, __currentAddress);
  }
}

// simple numeric pagination with ellipses
function __renderPageNumbers() {
  const parts = [];
  const push = (n, active) =>
    `<div class="page-number ${
      active ? "active" : ""
    }" onclick="goToPage(${n})">${n}</div>`;
  // Always show 1
  if (__currentPage === 1) parts.push(push(1, true));
  else parts.push(push(1, false));
  // Ellipsis if we're beyond page 3
  if (__currentPage > 3) parts.push('<div class="page-ellipsis">…</div>');
  // Middle window
  const start = Math.max(2, __currentPage - 1);
  const end = __nextUrl ? __currentPage + 1 : __currentPage; // if has next, show one ahead
  for (let n = start; n <= end; n++) {
    parts.push(push(n, n === __currentPage));
  }

  if (__nextUrl) parts.push('<div class="page-ellipsis">…</div>');
  return parts.join("");
}

function resetHistoryState(perPage) {
  __prevUrls = [];
  __currentPage = 1;
  __currentUrl = null;
  __nextUrl = null;
  __perPage = perPage || 10;
}

// Function to go to a specific page number
function goToPage(pageNumber) {
  if (pageNumber === __currentPage) {
    return; // Already on the page
  }

  // If going to page 1, just reset and load initial data
  if (pageNumber === 1) {
    __prevUrls = [];
    __currentPage = 1;
    const baseUrl = `https://api.trongrid.io/v1/accounts/${__currentAddress}/transactions?limit=${__perPage}`;
    transactionHistory(baseUrl, __currentAddress);
    return;
  }

  // If trying to go forward
  if (pageNumber > __currentPage) {
    // We can only go one page forward at a time due to API pagination limitations
    if (pageNumber === __currentPage + 1 && __nextUrl) {
      goToNextPage();
      return;
    }
  }

  // If trying to go backward
  if (pageNumber < __currentPage) {
    // Check if we have the page in our history
    const targetPrevUrl = __prevUrls.find((prev) => prev.page === pageNumber);
    if (targetPrevUrl) {
      // We found the exact page in history
      while (
        __prevUrls.length > 0 &&
        __prevUrls[__prevUrls.length - 1].page >= pageNumber
      ) {
        __prevUrls.pop();
      }
      __currentPage = pageNumber;
      transactionHistory(targetPrevUrl.url, __currentAddress);
      return;
    } else {
      // We need to go back to page 1 and build our way up
      const baseUrl = `https://api.trongrid.io/v1/accounts/${__currentAddress}/transactions?limit=${__perPage}`;
      __prevUrls = [];
      __currentPage = 1;
      transactionHistory(baseUrl, __currentAddress);

      if (typeof notify === "function") {
        notify(
          "Navigating to page 1 due to API pagination limitations",
          "info",
          3000
        );
      }
    }
  }
}