// Siacoin Wallet — bundled Theseus add-on. activate() runs in the main
// process; keys are re-derived from the password vault on every launch and
// live only in memory. Chain access goes through a walletd node the user
// configures (Settings); no default endpoint ships with the add-on.
const NETWORK = "mainnet";
const PURPOSE = "siawallet/mainnet/0";
const EXPLORER_TX = "https://siascan.com/tx/";
const EXPLORER_ADDR = "https://siascan.com/address/";
const SC = 10n ** 24n;
const ALLOWANCES = [100n * SC, 1000n * SC, 10000n * SC];

let ctx = null;   // { api, d, keys, wallet, client, root, phase, error }

async function deps(api) {
  const { ed25519 } = await api.import("@noble/curves/ed25519.js");
  const { blake2b } = await api.import("@noble/hashes/blake2.js");
  const sia = require("./lib/sia.js")({ ed25519, blake2b });
  const keysLib = require("./lib/keys.js")({ sia });
  const walletd = require("./lib/walletd.js")({ log: (...a) => api.log("walletd", ...a) });
  return { sia, keysLib, walletd };
}

const walletdUrl = (api) => String(api.storage.get("walletdUrl", "") || "").trim();
const fmt = (h) => ctx.d.sia.formatSC(h);

function snapshot() {
  const c = ctx;
  const base = {
    network: NETWORK, phase: c.phase, error: c.error,
    server: c.client ? c.client.displayUrl : null,
    hasUrl: !!walletdUrl(c.api),
    explorerTx: EXPLORER_TX, explorerAddr: EXPLORER_ADDR,
  };
  if (c.wallet) Object.assign(base, c.wallet.snapshot());
  return base;
}
function emitState() { try { ctx.api.emit("state", snapshot()); } catch {} }
function setPhase(phase, error = null) { ctx.phase = phase; ctx.error = error; emitState(); }

function buildWallet() {
  const c = ctx;
  if (c.wallet) { c.wallet.dispose(); c.wallet = null; }
  if (!c.keys) c.keys = new c.d.keysLib.WalletKeys(c.root);
  const url = walletdUrl(c.api);
  if (!url) { setPhase("nourl"); return; }
  if (!c.client) c.client = new c.d.walletd.Client(url); else c.client.setBase(url);
  c.wallet = require("./lib/wallet.js")({
    client: c.client, keys: c.keys, sia: c.d.sia, storage: c.api.storage,
    log: (...a) => c.api.log("wallet", ...a), onChange: emitState,
  });
  c.api.log("wallet ready, receive address", c.keys.entry(0).address, "via", c.client.displayUrl);
  setPhase("ready");
  c.wallet.refresh(true).then(() => c.wallet && c.wallet.startPolling());
}

async function deriveAndStart() {
  const c = ctx;
  setPhase("locked");
  try { c.root = await c.api.vault.derive(PURPOSE); }
  catch (e) {
    const msg = e?.message || String(e);
    setPhase(/not set up/i.test(msg) ? "nosetup" : "error", msg);
    return;
  }
  if (ctx !== c) return;
  try { buildWallet(); }
  catch (e) { setPhase("error", e?.message || String(e)); c.api.log("wallet build failed:", e?.message); }
}

function requireReady() {
  if (!ctx || ctx.phase !== "ready" || !ctx.wallet) throw new Error(ctx && ctx.phase === "nourl" ? "no walletd URL configured" : "wallet is not ready (vault locked?)");
  return ctx;
}
const fromPanel = (m) => { if (!m || m.from !== "panel") throw new Error("panel-only message"); };
function planFrom(p) {
  const c = requireReady();
  const spec = p || {};
  const targets = Array.isArray(spec.outputs) && spec.outputs.length
    ? spec.outputs.map((o) => ({ to: o.to, value: toHastings(o.amount ?? o.value) }))
    : [{ to: spec.to, value: toHastings(spec.amount ?? spec.value) }];
  return c.wallet.plan({ targets, feeMultiplier: spec.feeMultiplier, sendMax: !!spec.sendMax });
}
// Amounts arrive as decimal hastings strings (or numbers for small values).
function toHastings(v) {
  if (typeof v === "bigint") return v;
  const s = String(v ?? "0").trim();
  if (!/^\d+$/.test(s)) throw new Error("amount must be an integer number of hastings");
  return BigInt(s);
}
function describePlan(plan) {
  const sent = plan.recipients.reduce((a, r) => a + BigInt(r.value), 0n);
  return { recipients: plan.recipients, fee: plan.fee.toString(), feePerByte: plan.feePerByte.toString(), inputs: plan.tx.inputs.length, change: plan.change.toString(), total: (sent + plan.fee).toString() };
}

function registerPanelMessages(api) {
  api.onMessage("state", (_p, m) => { fromPanel(m); return snapshot(); });
  api.onMessage("refresh", async (_p, m) => { fromPanel(m); const c = requireReady(); await c.wallet.refresh(true); return snapshot(); });
  api.onMessage("nextAddress", (_p, m) => { fromPanel(m); const c = requireReady(); c.wallet.nextUnusedAddress(); return snapshot(); });
  api.onMessage("openUrl", (p, m) => { fromPanel(m); api.openTab(String(p && p.url || "")); return true; });
  api.onMessage("settings", (_p, m) => { fromPanel(m); return { walletdUrl: walletdUrl(api) }; });
  api.onMessage("setSettings", (p, m) => {
    fromPanel(m);
    const patch = p || {};
    if ("walletdUrl" in patch) {
      const v = String(patch.walletdUrl || "").trim();
      if (v && !/^https?:\/\/[^\s]+$/i.test(v)) throw new Error("walletd URL must start with http:// or https://");
      api.storage.set("walletdUrl", v);
    }
    if (ctx && ctx.root) buildWallet();
    return snapshot();
  });
  api.onMessage("planSend", (p, m) => { fromPanel(m); return describePlan(planFrom(p)); });
  api.onMessage("send", async (p, m) => {
    fromPanel(m);
    const c = requireReady();
    const plan = planFrom(p);
    const d = describePlan(plan);
    const pick = await api.approvalModal({
      title: "Send Siacoin?",
      origin: "Theseus wallet panel",
      rows: [
        { label: "To", value: d.recipients[0].to, mono: true },
        { label: "Amount", value: fmt(d.recipients[0].value) + " SC", strong: true },
        { label: "Fee", value: fmt(d.fee) + " SC" },
        { label: "Total", value: fmt(d.total) + " SC" },
      ],
      actions: [{ id: "send", label: "Send", primary: true }],
    });
    if (pick !== "send") throw new Error("cancelled");
    return c.wallet.signAndBroadcast(plan);
  });
  // Recovery: the 32-byte wallet seed (walletd KeyFromSeed scheme), only
  // after an explicit confirmation in the approval overlay.
  api.onMessage("recovery", async (p, m) => {
    fromPanel(m);
    const c = requireReady();
    const out = { purpose: PURPOSE, scheme: "walletd KeyFromSeed(seed, index); address = standard unlock hash", firstAddress: c.keys.entry(0).address };
    if (p && p.reveal) {
      const pick = await api.approvalModal({
        title: "Reveal the wallet seed?",
        origin: "Theseus wallet panel",
        body: "Anyone holding this seed can spend every coin in this wallet. It stays on screen until you close the Settings tab.",
        actions: [{ id: "reveal", label: "Reveal", danger: true }],
      });
      if (pick === "reveal") out.seedHex = c.keys.seedHex;
    }
    return out;
  });
}

// ---- dapp bridge (window.siacoin) ------------------------------------------
// permissions: { [origin]: { readAddress: true, sendTx: { cap, used, grantedAt } } }
// cap/used are hastings as decimal strings. No unlimited option; signing
// always asks.
const pendingByOrigin = new Set();
function permissions(api) { const p = api.storage.get("permissions", {}); return p && typeof p === "object" ? p : {}; }
const fromPage = (m) => { if (!m || m.from !== "page" || !m.origin) throw new Error("page-only message"); return m.origin; };
async function withOriginLock(origin, fn) {
  if (pendingByOrigin.has(origin)) throw new Error("a wallet request from this site is already waiting for approval");
  pendingByOrigin.add(origin);
  try { return await fn(); } finally { pendingByOrigin.delete(origin); }
}

function registerPageMessages(api) {
  api.onMessage("getAddress", async (_p, m) => {
    const origin = fromPage(m);
    const c = requireReady();
    const perms = permissions(api);
    if (perms[origin] && perms[origin].readAddress) return c.wallet.current().address;
    return withOriginLock(origin, async () => {
      const pick = await api.approvalModal({
        title: "Share your Siacoin address?",
        origin,
        body: "The site will see your current receiving address and can look up its balance and history on the public chain.",
        rows: [{ label: "Address", value: c.wallet.current().address, mono: true }],
        actions: [{ id: "allow", label: "Share", primary: true }],
        checkbox: { id: "always", label: "Always allow this site to see my address" },
      });
      if (!pick.startsWith("allow")) throw new Error("user rejected");
      if (pick === "allow+always") { perms[origin] = { ...(perms[origin] || {}), readAddress: true }; api.storage.set("permissions", perms); emitState(); }
      return c.wallet.current().address;
    });
  });
  api.onMessage("signAndSend", async (p, m) => {
    const origin = fromPage(m);
    const c = requireReady();
    return withOriginLock(origin, async () => {
      let plan;
      try { plan = planFrom(p); }
      catch (e) { throw new Error(/insufficient funds|balance/i.test(e?.message) ? "insufficient funds" : e?.message || String(e)); }
      const d = describePlan(plan);
      if (d.recipients.length > 8) throw new Error("too many outputs");
      const perms = permissions(api);
      const budget = perms[origin] && perms[origin].sendTx;
      const remaining = budget ? BigInt(budget.cap) - BigInt(budget.used || "0") : 0n;
      const total = BigInt(d.total);
      if (budget && total <= remaining) {
        const r = await c.wallet.signAndBroadcast(plan);
        budget.used = (BigInt(budget.used || "0") + total).toString();
        api.storage.set("permissions", perms);
        emitState();
        api.log(`silent send ${fmt(total)} SC for ${origin}, ${fmt(remaining - total)} SC of allowance left`);
        return { txid: r.txid };
      }
      const rows = d.recipients.map((r, i) => ({ label: d.recipients.length > 1 ? `To #${i + 1}` : "To", value: r.to, mono: true }));
      rows.push({ label: "Amount", value: fmt(d.recipients.reduce((a, r) => a + BigInt(r.value), 0n)) + " SC", strong: true });
      rows.push({ label: "Fee", value: fmt(d.fee) + " SC" });
      rows.push({ label: "Total", value: fmt(d.total) + " SC" });
      const pick = await api.approvalModal({
        title: "Send Siacoin?",
        origin,
        body: budget
          ? `This payment is over what is left of the site's allowance (${fmt(remaining)} SC). Check the address and amount.`
          : "This site is asking your wallet to pay. Check the address and amount.",
        rows,
        actions: [{ id: "send", label: "Send", primary: true }],
        select: {
          id: "cap", label: "Afterwards",
          options: [{ value: "", label: "ask every time" }, ...ALLOWANCES.map((s) => ({ value: s.toString(), label: `allow up to ${fmt(s)} SC more without asking` }))],
        },
      });
      const [action, ...flags] = pick.split("+");
      if (action !== "send") throw new Error("user rejected");
      const cap = flags.find((f) => f.startsWith("cap="));
      const capValue = cap ? cap.slice(4) : "";
      if (ALLOWANCES.some((a) => a.toString() === capValue)) {
        perms[origin] = { ...(perms[origin] || {}), sendTx: { cap: capValue, used: "0", grantedAt: Date.now() } };
        api.storage.set("permissions", perms);
      } else if (budget) {
        delete perms[origin].sendTx;
        api.storage.set("permissions", perms);
      }
      emitState();
      const r = await c.wallet.signAndBroadcast(plan);
      return { txid: r.txid };
    });
  });
  api.onMessage("signMessage", async (p, m) => {
    const origin = fromPage(m);
    const c = requireReady();
    const message = String(p && p.message != null ? p.message : "");
    if (message.length > 4096) throw new Error("message too long");
    return withOriginLock(origin, async () => {
      const entry = c.wallet.current();
      const pick = await api.approvalModal({
        title: "Sign a message?",
        origin,
        body: "Signing proves you control the address below. It moves no coins.",
        rows: [{ label: "Message", value: message.length > 400 ? message.slice(0, 400) + "…" : message, mono: true }, { label: "Address", value: entry.address, mono: true }],
        actions: [{ id: "sign", label: "Sign", primary: true }],
      });
      if (pick !== "sign") throw new Error("user rejected");
      const digest = c.d.sia.b256(new TextEncoder().encode(message));
      const sig = c.keys.sign(entry, digest);
      return { address: entry.address, publicKey: "ed25519:" + c.d.sia.toHex(entry.pub), signature: c.d.sia.toHex(sig) };
    });
  });
  api.onMessage("permissions", (_p, m) => { fromPanel(m); return permissions(api); });
  api.onMessage("revoke", (p, m) => {
    fromPanel(m);
    const perms = permissions(api);
    delete perms[String(p && p.origin || "")];
    api.storage.set("permissions", perms);
    return perms;
  });
}

module.exports = {
  activate(api) {
    api.registerSidebarPanel({ id: "main", title: "Sia", icon: "Ⓢ", page: "panel.html" });
    const c = ctx = { api, d: null, keys: null, wallet: null, client: null, root: null, phase: "locked", error: null };
    registerPanelMessages(api);
    registerPageMessages(api);
    deps(api).then((d) => { if (ctx !== c) return; c.d = d; return deriveAndStart(); })
      .catch((e) => { if (ctx !== c) return; setPhase("error", e?.message || String(e)); api.log("startup failed:", e?.message); });
  },
  deactivate() {
    const c = ctx; ctx = null;
    if (!c) return;
    try { c.wallet && c.wallet.dispose(); } catch {}
    try { c.keys && c.keys.wipe(); } catch {}
    if (c.root) c.root.fill(0);
  },
};