import fs from "node:fs";
import path from "node:path";
import { createHash, randomBytes } from "node:crypto";

const exactTargetUrl = "https://legacy-parity.mbn.local/index.html";
const expectedSourceSha256 =
  "1EE76BC464FB1C44C8B6546E99CDC21C726C0E2C24AD344F5C19AE41BFC0D2F2";
const expectedInitialDestinationSha256 =
  "13C07BA64587549EDA9C1A694F3DFA19875CB1F888F02C9E071F17C47739E087";
const expectedImportConfirmation =
  "현재 저장된 비교쌍의 순서는 그대로 유지하고, 원본 프로그램의 비교쌍 중 없는 항목만 뒤에 추가할까요?";
const allowedOutboundTypes = new Set([
  "ready",
  "select-tab",
  "choose-operator-folder",
  "import-legacy-comparison-pairs",
  "confirm-native-dialog"
]);
const forbiddenCdpMethods = new Set([
  "Browser.close",
  "Page.close",
  "Runtime.terminateExecution",
  "Target.closeTarget",
  "Input.dispatchMouseEvent",
  "Input.dispatchKeyEvent"
]);
const targetExpressions = Object.freeze({
  "settings-navigation": 'document.getElementById("workspace-settings-tab")',
  "design-folder-picker": 'document.getElementById("operator-design-folder-select")',
  "resource-folder-picker": 'document.getElementById("operator-resource-folder-select")',
  "background-folder-picker": 'document.getElementById("operator-background-folder-select")',
  "comparison-navigation":
    'document.querySelector("button[data-tab-id=\\"comparison\\"]")',
  "comparison-import":
    'document.querySelector("button[data-comparison-import=\\"true\\"]")',
  "native-confirmation-yes": 'document.getElementById("legacy-dialog-ok")'
});

class SmokeFailure extends Error {
  constructor(category, message) {
    super(`${category}: ${message}`);
    this.name = "SmokeFailure";
    this.category = category;
  }
}

function failKnown(message) {
  throw new SmokeFailure("KNOWN_FAILURE", message);
}

function failUnknown(message) {
  throw new SmokeFailure("OUTCOME_UNKNOWN", message);
}

function parseArguments(argv) {
  const accepted = new Set([
    "port", "output", "screenshot", "exchange-directory", "timeout-ms"
  ]);
  if (argv.length === 0 || argv.length % 2 !== 0) {
    failKnown(
      "Usage: node scripts/Test-LegacyPackageLocalStateSmoke.mjs " +
      "--port <port> --output <absolute.json> --screenshot <absolute.png> " +
      "--exchange-directory <absolute-directory> [--timeout-ms <milliseconds>]");
  }
  const values = new Map();
  for (let index = 0; index < argv.length; index += 2) {
    const rawName = argv[index];
    const value = argv[index + 1];
    if (!rawName?.startsWith("--") || !value) failKnown("Arguments must be --name value pairs.");
    const name = rawName.slice(2);
    if (!accepted.has(name) || values.has(name)) failKnown(`Invalid argument --${name}.`);
    values.set(name, value);
  }
  for (const required of ["port", "output", "screenshot", "exchange-directory"]) {
    if (!values.has(required)) failKnown(`--${required} is required.`);
  }
  const port = Number(values.get("port"));
  const timeoutMilliseconds = Number(values.get("timeout-ms") || "180000");
  if (!Number.isInteger(port) || port < 1024 || port > 65535) {
    failKnown("--port must be from 1024 through 65535.");
  }
  if (!Number.isInteger(timeoutMilliseconds) ||
      timeoutMilliseconds < 30_000 || timeoutMilliseconds > 900_000) {
    failKnown("--timeout-ms must be from 30000 through 900000.");
  }
  const outputPath = path.resolve(values.get("output"));
  const screenshotPath = path.resolve(values.get("screenshot"));
  const exchangeDirectory = path.resolve(values.get("exchange-directory"));
  if (!path.isAbsolute(values.get("output")) || path.extname(outputPath).toLowerCase() !== ".json" ||
      !path.isAbsolute(values.get("screenshot")) || path.extname(screenshotPath).toLowerCase() !== ".png" ||
      !path.isAbsolute(values.get("exchange-directory"))) {
    failKnown("Output, screenshot and exchange paths must be absolute and typed correctly.");
  }
  const unique = new Set([
    outputPath.toLowerCase(), screenshotPath.toLowerCase(), exchangeDirectory.toLowerCase()
  ]);
  if (unique.size !== 3) failKnown("Evidence paths must be distinct.");
  if (fs.existsSync(outputPath) || fs.existsSync(screenshotPath)) {
    failKnown("Evidence files are never overwritten.");
  }
  if (!fs.existsSync(exchangeDirectory) ||
      !fs.statSync(exchangeDirectory).isDirectory() ||
      fs.readdirSync(exchangeDirectory).length !== 0) {
    failKnown("The wrapper must provide one existing empty exchange directory.");
  }
  return { port, timeoutMilliseconds, outputPath, screenshotPath, exchangeDirectory };
}

const configuration = parseArguments(process.argv.slice(2));
const hardDeadline = Date.now() + configuration.timeoutMilliseconds;
const startedAt = new Date().toISOString();
let socket = null;
let nextRpcId = 1;
let nextInputSequence = 1;
let probeInstalled = false;
let cancellationRequested = false;
const pendingRpc = new Map();

const evidence = {
  schemaVersion: 1,
  profile: "local-settings-comparison-import",
  result: "RUNNING",
  startedAt,
  completedAt: null,
  target: {
    expectedUrl: exactTargetUrl,
    port: configuration.port,
    id: null,
    url: null
  },
  safety: {
    requiredMode: "dryRun",
    requiredPhase: "idle",
    allowedOutboundTypes: [...allowedOutboundTypes],
    observedOutboundTypes: [],
    blockedOutboundMessages: [],
    stateViolations: [],
    inputRetryCount: 0,
    appCloseRequested: false,
    playoutIntentIssued: false
  },
  files: {
    expectedSourceSha256,
    expectedSourceRowCount: 8,
    expectedInitialDestinationSha256,
    expectedInitialDestinationRowCount: 1,
    settingsBaseline: null,
    destinationAfterFirstImport: null,
    destinationAfterSecondImport: null
  },
  settings: {
    pickerKinds: [],
    allCancelled: false,
    settingsFileUnchanged: false
  },
  comparison: {
    initialPair: null,
    afterFirstImport: null,
    afterSecondImport: null,
    initialPairPreserved: false,
    secondImportIdempotent: false
  },
  exchanges: [],
  checkpoints: [],
  finalSnapshot: null,
  screenshot: null,
  error: null
};

process.stdin.setEncoding("utf8");
process.stdin.on("data", chunk => {
  if (String(chunk).split(/\r?\n/u).includes("CANCEL")) cancellationRequested = true;
});
// The wrapper keeps stdin open so it can fail-stop an in-flight helper. Do not
// let that control channel keep Node alive after PASS or a sealed early failure.
if (typeof process.stdin.unref === "function") process.stdin.unref();

function assertDeadline(label) {
  if (cancellationRequested) failUnknown(`The wrapper cancelled ${label}; no action is retried.`);
  if (Date.now() >= hardDeadline) failUnknown(`The global deadline expired ${label}; no action is retried.`);
}

async function sleep(milliseconds) {
  assertDeadline("before waiting");
  await new Promise(resolve => setTimeout(resolve, Math.min(milliseconds, hardDeadline - Date.now())));
  assertDeadline("after waiting");
}

function sha256(bytes) {
  return createHash("sha256").update(bytes).digest("hex").toUpperCase();
}

function stablePair(pair) {
  if (!pair) return null;
  return {
    rowId: pair.rowId,
    rowNumber: pair.rowNumber,
    displayLabel: pair.displayLabel,
    isSelected: pair.isSelected === true
  };
}

async function discoverTarget() {
  const discoveryUrl = `http://127.0.0.1:${configuration.port}/json/list`;
  let lastError = null;
  while (Date.now() < Math.min(hardDeadline, Date.now() + 15_000)) {
    try {
      const response = await fetch(discoveryUrl, { cache: "no-store" });
      if (!response.ok) throw new Error(`HTTP ${response.status}`);
      const targets = await response.json();
      const exact = targets.filter(target =>
        target?.type === "page" && target.url === exactTargetUrl);
      if (exact.length > 1) failKnown("More than one exact package WebView target exists.");
      if (exact.length === 1) return exact[0];
    } catch (error) {
      if (error instanceof SmokeFailure) throw error;
      lastError = String(error?.message || error);
    }
    await sleep(100);
  }
  failKnown(`The exact package target was not found${lastError ? ` (${lastError})` : ""}.`);
}

function validateEndpoint(target) {
  if (!target?.id || !target.webSocketDebuggerUrl) failKnown("The target has no debugger URL.");
  const endpoint = new URL(target.webSocketDebuggerUrl);
  if (endpoint.protocol !== "ws:" || endpoint.hostname !== "127.0.0.1" ||
      Number(endpoint.port) !== configuration.port ||
      endpoint.pathname !== `/devtools/page/${target.id}`) {
    failKnown("The debugger endpoint is not the exact loopback page endpoint.");
  }
  return endpoint;
}

async function connect(endpoint) {
  if (typeof WebSocket !== "function") failKnown("This Node runtime has no WebSocket API.");
  socket = new WebSocket(endpoint.href);
  await new Promise((resolve, reject) => {
    const timer = setTimeout(() => reject(new SmokeFailure(
      "OUTCOME_UNKNOWN", "CDP socket open timed out.")), 5_000);
    socket.addEventListener("open", () => { clearTimeout(timer); resolve(); }, { once: true });
    socket.addEventListener("error", () => { clearTimeout(timer); reject(new SmokeFailure(
      "OUTCOME_UNKNOWN", "CDP socket failed to open.")); }, { once: true });
  });
  socket.addEventListener("message", event => {
    const message = JSON.parse(String(event.data));
    if (!Object.hasOwn(message, "id")) return;
    const pending = pendingRpc.get(message.id);
    if (!pending) return;
    pendingRpc.delete(message.id);
    clearTimeout(pending.timer);
    if (message.error) pending.reject(new SmokeFailure(
      "KNOWN_FAILURE", `${pending.method} failed: ${message.error.message || "CDP error"}`));
    else pending.resolve(message.result);
  });
  socket.addEventListener("close", () => {
    for (const pending of pendingRpc.values()) {
      clearTimeout(pending.timer);
      pending.reject(new SmokeFailure(
        "OUTCOME_UNKNOWN", `CDP closed while waiting for ${pending.method}.`));
    }
    pendingRpc.clear();
  });
}

function rpc(method, params = {}, timeoutMilliseconds = 10_000) {
  assertDeadline(`before ${method}`);
  if (forbiddenCdpMethods.has(method)) {
    if (method.includes("close") || method.includes("terminate")) {
      evidence.safety.appCloseRequested = true;
    }
    failKnown(`Forbidden CDP method ${method} was refused.`);
  }
  if (!socket || socket.readyState !== WebSocket.OPEN) failUnknown("CDP socket is not open.");
  const id = nextRpcId++;
  return new Promise((resolve, reject) => {
    const timer = setTimeout(() => {
      pendingRpc.delete(id);
      reject(new SmokeFailure("OUTCOME_UNKNOWN", `${method} timed out; no retry was attempted.`));
    }, Math.min(timeoutMilliseconds, hardDeadline - Date.now()));
    pendingRpc.set(id, { method, resolve, reject, timer });
    socket.send(JSON.stringify({ id, method, params }));
  });
}

async function evaluate(expression) {
  const response = await rpc("Runtime.evaluate", {
    expression,
    awaitPromise: true,
    returnByValue: true,
    userGesture: false
  });
  if (response.exceptionDetails) {
    failKnown(response.exceptionDetails.exception?.description ||
      response.exceptionDetails.text || "Runtime evaluation failed.");
  }
  return response.result?.value;
}

async function installProbe() {
  const token = `local-state-${Date.now()}-${randomBytes(8).toString("hex")}`;
  const installed = await evaluate(`(() => {
    if (!window.chrome?.webview) throw new Error("WebView2 bridge is unavailable.");
    if (globalThis.__legacyLocalStateProbe) throw new Error("Probe already exists.");
    const allowed = new Set(${JSON.stringify([...allowedOutboundTypes])});
    const probe = {
      token: ${JSON.stringify(token)}, states: [], outboundMessages: [], pointerEvents: [],
      blockedOutboundMessages: [], stateViolations: [], originalPostMessage: null,
      postMessageWrapper: null, listener: null, pointerListener: null
    };
    probe.listener = event => {
      if (event.data?.type !== "state" || !event.data.payload) return;
      const payload = event.data.payload;
      probe.states.push(structuredClone(payload));
      if (probe.states.length > 500) probe.states.shift();
      const playout = payload.playout;
      const reasons = [];
      if (!playout) reasons.push("missing-playout");
      else {
        if (playout.mode !== "dryRun") reasons.push("mode");
        if (playout.phase !== "idle") reasons.push("phase");
        if (playout.isConnected === true) reasons.push("connected");
        if (playout.preparedCode != null) reasons.push("prepared");
        if (playout.onAirCode != null) reasons.push("on-air");
        if (playout.outcomeUnknown === true) reasons.push("outcome-unknown");
        if (playout.isPlayCompletionPending === true) reasons.push("play-pending");
        if (playout.isTakeOutCompletionPending === true) reasons.push("takeout-pending");
        if (playout.isBusy === true) reasons.push("playout-busy");
        if (playout.refreshActive === true) reasons.push("refresh-active");
      }
      if (reasons.length) probe.stateViolations.push({
        at: new Date().toISOString(), revision: payload.revision ?? null, reasons
      });
    };
    probe.originalPostMessage = window.chrome.webview.postMessage;
    probe.pointerListener = event => {
      const element = event.target instanceof Element ? event.target : null;
      let targetId = null;
      if (element?.closest("#workspace-settings-tab")) targetId = "settings-navigation";
      else if (element?.closest("#operator-design-folder-select")) {
        targetId = "design-folder-picker";
      } else if (element?.closest("#operator-resource-folder-select")) {
        targetId = "resource-folder-picker";
      } else if (element?.closest("#operator-background-folder-select")) {
        targetId = "background-folder-picker";
      } else if (element?.closest('button[data-tab-id="comparison"]')) {
        targetId = "comparison-navigation";
      } else if (element?.closest('button[data-comparison-import="true"]')) {
        targetId = "comparison-import";
      } else if (element?.closest("#legacy-dialog-ok")) {
        targetId = "native-confirmation-yes";
      }
      probe.pointerEvents.push({
        sequence: probe.pointerEvents.length + 1,
        type: event.type,
        targetId,
        isTrusted: event.isTrusted === true,
        pointerType: event.pointerType,
        button: event.button,
        buttons: event.buttons,
        at: new Date().toISOString()
      });
      if (probe.pointerEvents.length > 100) probe.pointerEvents.shift();
    };
    probe.postMessageWrapper = message => {
      const record = {
        sequence: probe.outboundMessages.length + 1,
        type: typeof message?.type === "string" ? message.type : null,
        at: new Date().toISOString()
      };
      probe.outboundMessages.push(record);
      if (!record.type || !allowed.has(record.type)) {
        probe.blockedOutboundMessages.push(record);
        return;
      }
      return probe.originalPostMessage.call(window.chrome.webview, message);
    };
    try {
      window.chrome.webview.postMessage = probe.postMessageWrapper;
      if (window.chrome.webview.postMessage !== probe.postMessageWrapper) {
        throw new Error("The outbound safety gate could not be installed.");
      }
      globalThis.__legacyLocalStateProbe = probe;
      window.chrome.webview.addEventListener("message", probe.listener);
      document.addEventListener("pointerdown", probe.pointerListener, true);
      document.addEventListener("pointerup", probe.pointerListener, true);
      window.chrome.webview.postMessage({ type: "ready", payload: {} });
    } catch (error) {
      window.chrome.webview.postMessage = probe.originalPostMessage;
      delete globalThis.__legacyLocalStateProbe;
      throw error;
    }
    return probe.token;
  })()`);
  if (installed !== token) failKnown("The probe was not installed exactly once.");
  probeInstalled = true;
}

async function removeProbe() {
  if (!probeInstalled || !socket || socket.readyState !== WebSocket.OPEN) return;
  const removed = await evaluate(`(() => {
    const probe = globalThis.__legacyLocalStateProbe;
    if (!probe) return false;
    window.chrome.webview.removeEventListener("message", probe.listener);
    document.removeEventListener("pointerdown", probe.pointerListener, true);
    document.removeEventListener("pointerup", probe.pointerListener, true);
    if (window.chrome.webview.postMessage !== probe.postMessageWrapper) {
      throw new Error("The outbound safety gate identity changed.");
    }
    window.chrome.webview.postMessage = probe.originalPostMessage;
    delete globalThis.__legacyLocalStateProbe;
    return true;
  })()`);
  if (removed !== true) failUnknown("The safety probe was not restored exactly once.");
  probeInstalled = false;
}

async function readSnapshot() {
  return await evaluate(`(() => {
    const probe = globalThis.__legacyLocalStateProbe;
    const state = probe?.states?.at(-1) || null;
    const active = document.activeElement;
    return {
      state: state ? structuredClone(state) : null,
      safety: {
        wrapped: probe?.postMessageWrapper != null &&
          window.chrome?.webview?.postMessage === probe.postMessageWrapper,
        outboundMessages: (probe?.outboundMessages || []).map(value => ({ ...value })),
        blockedOutboundMessages: (probe?.blockedOutboundMessages || []).map(value => ({ ...value })),
        stateViolations: (probe?.stateViolations || []).map(value => ({
          ...value, reasons: [...value.reasons]
        }))
      },
      dom: {
        url: location.href,
        readyState: document.readyState,
        bodyBusy: document.body.getAttribute("aria-busy"),
        connectionText: (document.getElementById("playout-connection-state")?.textContent || "").trim(),
        settingsVisible: document.getElementById("settings-workspace")?.hidden === false &&
          document.getElementById("settings-workspace")?.inert !== true,
        settingsCurrent: document.getElementById("workspace-settings-tab")
          ?.getAttribute("aria-current"),
        activeTabId: state?.tabs?.find(tab => tab.isActive === true)?.id || null,
        legacyDialogHidden: document.getElementById("legacy-dialog")?.hidden === true,
        legacyDialogText: (document.getElementById("legacy-dialog-message")?.textContent || "").trim(),
        legacyDialogOkText: (document.getElementById("legacy-dialog-ok")?.textContent || "").trim(),
        importStatus: (document.querySelector(".comparison-import-status")?.textContent || "").trim(),
        activeElementId: active?.id || null
      }
    };
  })()`);
}

function assertSafety(snapshot, label, { allowBusy = false, allowDialog = false } = {}) {
  if (!snapshot?.state?.playout) failKnown(`Native state is missing at ${label}.`);
  const playout = snapshot.state.playout;
  if (snapshot.safety.wrapped !== true) failUnknown(`The safety gate is absent at ${label}.`);
  evidence.safety.observedOutboundTypes = snapshot.safety.outboundMessages.map(row => row.type);
  evidence.safety.blockedOutboundMessages = snapshot.safety.blockedOutboundMessages;
  evidence.safety.stateViolations = snapshot.safety.stateViolations;
  evidence.safety.playoutIntentIssued = snapshot.safety.outboundMessages.some(row =>
    ["prepare-playout", "take-in", "next-playout", "take-out",
      "choose-background", "toggle-background"].includes(row.type));
  if (snapshot.safety.blockedOutboundMessages.length) {
    failKnown(`An unapproved outbound message was blocked at ${label}.`);
  }
  if (snapshot.safety.stateViolations.length) failUnknown(`DryRun left its safe state at ${label}.`);
  if (playout.mode !== "dryRun" || playout.phase !== "idle" ||
      playout.isConnected === true || playout.preparedCode != null ||
      playout.onAirCode != null || playout.outcomeUnknown === true ||
      playout.isPlayCompletionPending === true ||
      playout.isTakeOutCompletionPending === true || playout.isBusy === true ||
      playout.refreshActive === true) {
    failUnknown(`Playout is not exact DryRun IDLE at ${label}.`);
  }
  if (!allowBusy && snapshot.state.isBusy === true) failKnown(`The UI is busy at ${label}.`);
  if (!allowDialog && snapshot.dom.legacyDialogHidden !== true) {
    failKnown(`An unexpected native dialog is visible at ${label}.`);
  }
  if (snapshot.dom.url !== exactTargetUrl || snapshot.dom.readyState !== "complete" ||
      snapshot.dom.connectionText !== "DRY RUN") {
    failKnown(`The exact DryRun document is not ready at ${label}.`);
  }
}

async function waitFor(label, predicate, options = {}) {
  const allowMissingState = options.allowMissingState === true;
  if (allowMissingState && label !== "DryRun IDLE preflight") {
    failKnown("Only the input-free initial preflight may await the first native state.");
  }
  const deadline = Math.min(hardDeadline, Date.now() + (options.timeoutMilliseconds || 45_000));
  let last = null;
  while (Date.now() < deadline) {
    last = await readSnapshot();
    if (!last?.state?.playout && allowMissingState) {
      if (last?.safety?.wrapped !== true) {
        failUnknown("The safety gate is absent while awaiting the first native state.");
      }
      evidence.safety.observedOutboundTypes =
        last.safety.outboundMessages.map(row => row.type);
      evidence.safety.blockedOutboundMessages = last.safety.blockedOutboundMessages;
      evidence.safety.stateViolations = last.safety.stateViolations;
      if (last.safety.blockedOutboundMessages.length) {
        failKnown("An unapproved outbound message was blocked before initial state.");
      }
      if (last.safety.stateViolations.length) {
        failUnknown("A native state violation was observed before initial state.");
      }
      if (last.dom.url !== exactTargetUrl || last.dom.readyState !== "complete" ||
          last.dom.connectionText !== "DRY RUN") {
        failKnown("The exact DryRun document changed while awaiting initial state.");
      }
      await sleep(100);
      continue;
    }
    assertSafety(last, label, options);
    if (predicate(last)) return last;
    await sleep(100);
  }
  failUnknown(`Timed out waiting for ${label}; no input was retried.`);
}

function exchangePath(sequence, suffix) {
  return path.join(configuration.exchangeDirectory,
    `${String(sequence).padStart(2, "0")}.${suffix}.json`);
}

function readSmallJson(filePath, label) {
  const stat = fs.statSync(filePath);
  if (!stat.isFile() || stat.size <= 0 || stat.size > 64 * 1024) {
    failKnown(`${label} is empty or too large.`);
  }
  const bytes = fs.readFileSync(filePath);
  let value;
  try { value = JSON.parse(bytes.toString("utf8")); }
  catch { failKnown(`${label} is not strict JSON.`); }
  return { bytes, value, sha256: sha256(bytes) };
}

async function elementGeometry(targetId) {
  const expression = targetExpressions[targetId];
  if (!expression) failKnown(`Closed target ${targetId} is unavailable.`);
  const value = await evaluate(`(() => {
    const element = ${expression};
    if (!element) return null;
    element.scrollIntoView({ block: "nearest", inline: "nearest" });
    const rect = element.getBoundingClientRect();
    return {
      x: rect.left + rect.width / 2, y: rect.top + rect.height / 2,
      width: rect.width, height: rect.height,
      viewport: { width: document.documentElement.clientWidth,
        height: document.documentElement.clientHeight },
      devicePixelRatio: window.devicePixelRatio,
      disabled: element.disabled === true,
      hidden: element.hidden === true || element.closest("[hidden]") != null,
      text: (element.textContent || "").trim(),
      ariaCurrent: element.getAttribute("aria-current")
    };
  })()`);
  if (!value || value.disabled || value.hidden || value.width <= 0 || value.height <= 0 ||
      !Number.isFinite(value.x) || !Number.isFinite(value.y) ||
      value.x < 0 || value.y < 0 || value.x >= value.viewport.width ||
      value.y >= value.viewport.height ||
      value.devicePixelRatio < 0.25 || value.devicePixelRatio > 5) {
    failKnown(`${targetId} is not a unique visible input target.`);
  }
  return value;
}

async function requestExchange(operation, targetId = null, folderKind = null) {
  const sequence = nextInputSequence++;
  const token = randomBytes(16).toString("hex").toUpperCase();
  const geometry = targetId ? await elementGeometry(targetId) : null;
  const pointerEventStart = operation === "observe-local-files" ? null :
    await evaluate("globalThis.__legacyLocalStateProbe?.pointerEvents?.length ?? null");
  if (operation !== "observe-local-files" && !Number.isInteger(pointerEventStart)) {
    failUnknown("The trusted pointer evidence baseline is unavailable.");
  }
  const request = {
    schemaVersion: 1,
    token,
    sequence,
    targetUrl: exactTargetUrl,
    operation,
    targetId,
    folderKind,
    point: geometry ? { x: geometry.x, y: geometry.y } : null,
    viewport: geometry ? geometry.viewport : null,
    devicePixelRatio: geometry ? geometry.devicePixelRatio : null,
    mouseDownCalls: operation === "observe-local-files" ? 0 : 1,
    mouseUpCalls: operation === "observe-local-files" ? 0 : 1,
    escapeKeyCalls: operation === "folder-picker-click-cancel" ? 1 : 0,
    inputRetryCount: 0
  };
  const requestPath = exchangePath(sequence, "request");
  const acknowledgementPath = exchangePath(sequence, "ack");
  const requestBytes = Buffer.from(`${JSON.stringify(request)}\n`, "utf8");
  fs.writeFileSync(requestPath, requestBytes, { flag: "wx" });
  const deadline = Math.min(hardDeadline, Date.now() + 45_000);
  while (!fs.existsSync(acknowledgementPath)) {
    if (Date.now() >= deadline) failUnknown(`Input exchange ${sequence} timed out; no retry was attempted.`);
    await sleep(50);
  }
  const acknowledgement = readSmallJson(acknowledgementPath,
    `Input acknowledgement ${sequence}`);
  const ack = acknowledgement.value;
  if (!ack || ack.schemaVersion !== 1 || ack.token !== token || ack.sequence !== sequence ||
      ack.result !== "PASS" || ack.operation !== operation || ack.targetId !== targetId ||
      ack.folderKind !== folderKind || ack.packageIdentityValidated !== true ||
      ack.dryRunValidated !== true || ack.tornadoConnectionCount !== 0 ||
      ack.inputRetryCount !== 0 || ack.mouseDownCalls !== request.mouseDownCalls ||
      ack.mouseUpCalls !== request.mouseUpCalls || ack.escapeKeyCalls !== request.escapeKeyCalls ||
      !ack.files) {
    failKnown(`Input acknowledgement ${sequence} does not match its one-shot request.`);
  }
  const physicalPointer = operation === "observe-local-files"
    ? null : await waitForTrustedPointerClick(targetId, pointerEventStart);
  evidence.exchanges.push({
    sequence, operation, targetId, folderKind,
    requestPath, requestSha256: sha256(requestBytes),
    acknowledgementPath, acknowledgementSha256: acknowledgement.sha256,
    picker: ack.picker || null,
    physicalPointer,
    files: ack.files
  });
  return ack;
}

async function waitForTrustedPointerClick(targetId, startIndex) {
  const deadline = Math.min(hardDeadline, Date.now() + 10_000);
  while (Date.now() < deadline) {
    const events = await evaluate(`(() => {
      const events = globalThis.__legacyLocalStateProbe?.pointerEvents || [];
      return events.slice(${Number(startIndex)}).map(value => ({ ...value }));
    })()`);
    const relevant = events.filter(event => event.targetId === targetId);
    if (relevant.length >= 2) {
      const down = relevant.find(event => event.type === "pointerdown");
      const up = relevant.find(event => event.type === "pointerup");
      if (!down || !up || down.sequence >= up.sequence || down.isTrusted !== true ||
          up.isTrusted !== true || down.pointerType !== "mouse" ||
          up.pointerType !== "mouse" || down.button !== 0 || up.button !== 0 ||
          down.buttons !== 1 || up.buttons !== 0) {
        failKnown(`The ${targetId} click did not produce one trusted mouse down/up pair.`);
      }
      return { down, up };
    }
    await sleep(25);
  }
  failUnknown(`Trusted pointer evidence for ${targetId} did not appear; no click was retried.`);
}

function assertExactPreflightFiles(files) {
  if (files.source?.sha256 !== expectedSourceSha256 || files.source?.rowCount !== 8 ||
      files.source?.isReadOnlySource !== true ||
      files.destination?.sha256 !== expectedInitialDestinationSha256 ||
      files.destination?.rowCount !== 1 ||
      files.destination?.firstPair !== "KRX100지수|코스피 지수") {
    failKnown("The original source or one-row current comparison baseline changed.");
  }
  evidence.files.settingsBaseline = files.settings;
}

function assertSettingsUnchanged(files, label) {
  if (JSON.stringify(files.settings) !== JSON.stringify(evidence.files.settingsBaseline)) {
    failKnown(`The settings JSON changed ${label}.`);
  }
}

async function runSequence() {
  await rpc("Runtime.enable");
  await rpc("Page.enable");
  await installProbe();
  const initial = await waitFor("DryRun IDLE preflight", snapshot =>
    snapshot.state?.playout?.mode === "dryRun" && snapshot.state.isBusy !== true,
  { allowBusy: false, allowMissingState: true });

  const preflight = await requestExchange("observe-local-files");
  assertExactPreflightFiles(preflight.files);
  evidence.checkpoints.push({ name: "exact-file-preflight", files: preflight.files });

  await requestExchange("application-click", "settings-navigation");
  await waitFor("settings workspace", snapshot =>
    snapshot.dom.settingsVisible === true && snapshot.dom.settingsCurrent === "page",
  { allowBusy: false });

  for (const [targetId, folderKind] of [
    ["design-folder-picker", "design"],
    ["resource-folder-picker", "resource"],
    ["background-folder-picker", "background"]
  ]) {
    const ack = await requestExchange("folder-picker-click-cancel", targetId, folderKind);
    if (!ack.picker || ack.picker.uniqueNewPicker !== true ||
        ack.picker.ownerLinkedToApplication !== true ||
        ack.picker.escapeCancelled !== true || ack.picker.closedAfterEscape !== true) {
      failKnown(`The ${folderKind} folder picker was not proven as the app-owned cancelled picker.`);
    }
    assertSettingsUnchanged(ack.files, `after cancelling ${folderKind}`);
    evidence.settings.pickerKinds.push(folderKind);
    await waitFor(`${folderKind} picker cancellation return`, snapshot =>
      snapshot.state.isBusy !== true && snapshot.dom.settingsVisible === true &&
      snapshot.dom.legacyDialogHidden === true,
    { allowBusy: false });
  }
  const settingsObservation = await requestExchange("observe-local-files");
  assertSettingsUnchanged(settingsObservation.files, "after all three picker cancellations");
  evidence.settings.allCancelled = true;
  evidence.settings.settingsFileUnchanged = true;

  await requestExchange("application-click", "comparison-navigation");
  let comparison = await waitFor("comparison one-row baseline", snapshot =>
    snapshot.state.isBusy !== true && snapshot.dom.activeTabId === "comparison" &&
    snapshot.state.comparison?.isBusy !== true &&
    snapshot.state.comparison?.savedPairs?.length === 1 &&
    snapshot.state.comparison?.canImportLegacyPairs === true,
  { allowBusy: false });
  const initialPair = stablePair(comparison.state.comparison.savedPairs[0]);
  if (typeof initialPair?.rowId !== "string" || initialPair.rowId.length === 0 ||
      initialPair.rowNumber !== 1 ||
      initialPair.displayLabel !== "KRX100지수 ↔ 코스피 지수") {
    failKnown("The visible one-row comparison baseline is not the expected known pair.");
  }
  evidence.comparison.initialPair = initialPair;

  await requestExchange("application-click", "comparison-import");
  await waitFor("first import confirmation", snapshot =>
    snapshot.state.dialog?.isConfirmation === true &&
    snapshot.state.dialog?.message === expectedImportConfirmation &&
    snapshot.dom.legacyDialogHidden === false &&
    snapshot.dom.legacyDialogText === expectedImportConfirmation &&
    snapshot.dom.legacyDialogOkText === "예",
  { allowBusy: false, allowDialog: true });
  await requestExchange("application-click", "native-confirmation-yes");
  comparison = await waitFor("first import completion", snapshot => {
    const model = snapshot.state.comparison;
    const receipt = model?.lastImport;
    return snapshot.state.isBusy !== true && model?.isBusy !== true &&
      snapshot.dom.legacyDialogHidden === true && model?.savedPairs?.length === 9 &&
      receipt?.sourceSha256 === expectedSourceSha256 && receipt?.sourceRowCount === 8 &&
      receipt?.addedPairCount === 8 && receipt?.skippedDuplicateCount === 0 &&
      receipt?.totalPairCount === 9;
  }, { allowBusy: true, allowDialog: true, timeoutMilliseconds: 90_000 });
  const afterFirstPairs = comparison.state.comparison.savedPairs.map(stablePair);
  if (JSON.stringify(afterFirstPairs[0]) !== JSON.stringify(initialPair)) {
    failKnown("The original current comparison pair was not preserved at the front.");
  }
  evidence.comparison.initialPairPreserved = true;
  evidence.comparison.afterFirstImport = {
    receipt: comparison.state.comparison.lastImport,
    pairCount: afterFirstPairs.length,
    pairs: afterFirstPairs
  };
  const afterFirstFiles = await requestExchange("observe-local-files");
  assertSettingsUnchanged(afterFirstFiles.files, "after the first comparison import");
  if (afterFirstFiles.files.destination?.rowCount !== 9 ||
      afterFirstFiles.files.destination?.firstPair !== "KRX100지수|코스피 지수" ||
      afterFirstFiles.files.destination?.sha256 === expectedInitialDestinationSha256) {
    failKnown("The first comparison import file is not an appended nine-row result.");
  }
  evidence.files.destinationAfterFirstImport = afterFirstFiles.files.destination;

  await requestExchange("application-click", "comparison-import");
  await waitFor("second import confirmation", snapshot =>
    snapshot.state.dialog?.isConfirmation === true &&
    snapshot.state.dialog?.message === expectedImportConfirmation &&
    snapshot.dom.legacyDialogHidden === false,
  { allowBusy: false, allowDialog: true });
  await requestExchange("application-click", "native-confirmation-yes");
  comparison = await waitFor("second import idempotent completion", snapshot => {
    const model = snapshot.state.comparison;
    const receipt = model?.lastImport;
    return snapshot.state.isBusy !== true && model?.isBusy !== true &&
      snapshot.dom.legacyDialogHidden === true && model?.savedPairs?.length === 9 &&
      receipt?.sourceSha256 === expectedSourceSha256 && receipt?.sourceRowCount === 8 &&
      receipt?.addedPairCount === 0 && receipt?.skippedDuplicateCount === 8 &&
      receipt?.totalPairCount === 9;
  }, { allowBusy: true, allowDialog: true, timeoutMilliseconds: 90_000 });
  const afterSecondPairs = comparison.state.comparison.savedPairs.map(stablePair);
  if (JSON.stringify(afterSecondPairs) !== JSON.stringify(afterFirstPairs)) {
    failKnown("The second import changed the ordered comparison pair list.");
  }
  const finalFiles = await requestExchange("observe-local-files");
  assertSettingsUnchanged(finalFiles.files, "after the second comparison import");
  if (JSON.stringify(finalFiles.files.destination) !==
      JSON.stringify(afterFirstFiles.files.destination)) {
    failKnown("The second import changed the comparison file hash or contents.");
  }
  if (finalFiles.files.source?.sha256 !== expectedSourceSha256 ||
      finalFiles.files.source?.rowCount !== 8) {
    failUnknown("The read-only original source changed during the smoke.");
  }
  evidence.files.destinationAfterSecondImport = finalFiles.files.destination;
  evidence.comparison.afterSecondImport = {
    receipt: comparison.state.comparison.lastImport,
    pairCount: afterSecondPairs.length,
    pairs: afterSecondPairs
  };
  evidence.comparison.secondImportIdempotent = true;

  const finalSnapshot = await readSnapshot();
  assertSafety(finalSnapshot, "final state", { allowBusy: false });
  evidence.finalSnapshot = finalSnapshot;
  await captureScreenshot();
  await removeProbe();
  if (nextInputSequence !== 14 || evidence.exchanges.length !== 13) {
    failUnknown("The closed thirteen-step exchange sequence did not complete exactly once.");
  }
  if (evidence.safety.observedOutboundTypes.filter(type =>
      type === "import-legacy-comparison-pairs").length !== 2 ||
      evidence.safety.observedOutboundTypes.filter(type =>
        type === "confirm-native-dialog").length !== 2 ||
      evidence.safety.observedOutboundTypes.filter(type =>
        type === "choose-operator-folder").length !== 3) {
    failKnown("The two import confirmations did not emit exactly two request/Yes pairs.");
  }
  evidence.result = "PASS";
}

async function captureScreenshot() {
  const response = await rpc("Page.captureScreenshot", {
    format: "png", fromSurface: true, captureBeyondViewport: false
  }, 20_000);
  if (!response?.data) failKnown("CDP returned no screenshot bytes.");
  const bytes = Buffer.from(response.data, "base64");
  fs.writeFileSync(configuration.screenshotPath, bytes, { flag: "wx" });
  evidence.screenshot = {
    path: configuration.screenshotPath,
    bytes: bytes.length,
    sha256: sha256(bytes)
  };
}

function errorProjection(error) {
  return {
    category: error instanceof SmokeFailure ? error.category : "HARNESS_ERROR",
    name: error?.name || "Error",
    message: String(error?.message || error)
  };
}

let exitCode = 0;
try {
  const target = await discoverTarget();
  evidence.target.id = target.id;
  evidence.target.url = target.url;
  await connect(validateEndpoint(target));
  await runSequence();
} catch (error) {
  exitCode = 1;
  evidence.result = error instanceof SmokeFailure && error.category === "OUTCOME_UNKNOWN"
    ? "OUTCOME_UNKNOWN" : "FAIL";
  evidence.error = errorProjection(error);
  try {
    if (!evidence.screenshot && socket?.readyState === WebSocket.OPEN) await captureScreenshot();
  } catch { /* Preserve the first failure. */ }
  try {
    if (probeInstalled && socket?.readyState === WebSocket.OPEN) await removeProbe();
  } catch { /* Preserve the first failure and leave state observable. */ }
} finally {
  evidence.completedAt = new Date().toISOString();
  try {
    const bytes = Buffer.from(`${JSON.stringify(evidence, null, 2)}\n`, "utf8");
    fs.writeFileSync(configuration.outputPath, bytes, { flag: "wx" });
  } catch {
    exitCode = 1;
  }
  if (socket?.readyState === WebSocket.OPEN) socket.close();
}

process.exitCode = exitCode;