const HOST_NAME = "com.project_info.bili_auth_ingress";
const SCHEMA = 3;
const EXTENSION_BUILD = "project-info-bili-auth-ingress/1.2.25+20260829.generic.v027";
const OWNED_TAB_STORAGE_KEY = "bili_auth_job_owned_tab_v1";
const OWNED_TAB_SCHEMA = 1;
const BVID_RE = /^BV1[1-9A-HJ-NP-Za-km-z]{9}$/;
const CREATOR_RE = /^[1-9][0-9]{0,19}$/;
const HEX32_RE = /^[0-9a-f]{32}$/;
const HEX64_RE = /^[0-9a-f]{64}$/;
const UPPER_HEX64_RE = /^[0-9A-F]{64}$/;
const MESSAGE_ID_RE = /^msg_[0-9]{17}_[0-9a-f]{8}$/;
const HANDOFF_ID_RE = /^HANDOFF-[A-Z0-9-]{8,240}$/;
const AUDIT_ID_RE = /^DEV-AUDIT-[A-Z0-9-]{8,240}$/;
const ERROR_CODE_RE = /^E_[A-Z0-9_]{1,48}$/;
const SAFE_PHASES = new Set([
  "IDLE", "READY", "CHECKING", "DOWNLOADING", "MERGING", "VALIDATING",
  "PUBLISHING", "MEDIA_COMPLETE", "POSTPROCESS_PENDING", "POSTPROCESS_FAILED",
  "COMPLETE", "FAILED", "CANCELED", "RELOAD_REQUIRED"
]);
const RESPONSE_KEYS = [
  "error_code", "formal_filename", "host_build", "job", "lease_id", "maintenance",
  "mapping_filename", "phase", "prepare_id", "progress", "schema", "type"
];
const JOB_KEYS = ["bvid", "canonical_url", "creator_uid", "expected_duration_ms", "job_id", "published_at", "title"];
const LINEAGE_KEYS = [
  "authorization_handoff_id", "authorization_message_id", "authorization_sha256",
  "predecessor_job_id", "predecessor_terminal_error_code", "repair_audit_bytes",
  "repair_audit_id", "repair_audit_sha256", "repair_review_result_message_id", "retry_generation"
];
const PREPARELESS_TERMINAL_DIAGNOSTIC_CONTRACT = new Map([
  ["E_DRM", ["PAGE_REJECTED", new Set(["PAGE_DRM_REJECTED"])]],
  ["E_DURATION", ["PAGE_REJECTED", new Set(["PAGE_DURATION_REJECTED"])]],
  ["E_MULTI_PART", ["PAGE_REJECTED", new Set(["PAGE_MULTIPART_REJECTED"])]],
  ["E_OWNER", ["PAGE_REJECTED", new Set(["PAGE_IDENTITY_REJECTED", "PAGE_OWNER_REJECTED"])]],
  ["E_PAGE_ACCESS_CONTROL", ["PAGE_REJECTED", new Set(["PAGE_ACCESS_REJECTED"])]],
  ["E_PAGE_DUPLICATE_TAB", ["TAB_IDENTITY", new Set(["TAB_IDENTITY_DRIFT"])]],
  ["E_PAGE_DIMENSIONS_UNAVAILABLE", ["DIMENSIONS_PENDING", new Set(["VIDEO_DIMENSIONS_PENDING"])]],
  ["E_PAGE_IDENTITY_UNAVAILABLE", ["IDENTITY_PENDING", new Set([
    "PAGE_DOM_IDENTITY_PENDING", "PAGE_NAVIGATION_PENDING", "PAGE_SCRIPTING_PENDING",
    "PAGE_TAB_ACTIVATION_PENDING", "PAGE_URL_PENDING", "PAGE_VISIBILITY_PENDING",
    "PAGE_WINDOW_FOCUS_PENDING", "PAGE_WINDOW_MINIMIZED_PENDING", "PAGE_WINDOW_STATE_PENDING"
  ])]],
  ["E_PAGE_METADATA_UNAVAILABLE", ["METADATA_NOT_READY", new Set([
    "INITIAL_STATE_ASSIGNMENT_ABSENT", "INITIAL_STATE_JSON_INVALID",
    "INITIAL_STATE_VIDEO_DATA_ABSENT"
  ])]],
  ["E_PAGE_OWNER_ANCHOR_UNAVAILABLE", ["OWNER_PENDING", new Set([
    "OWNER_ANCHOR_ABSENT", "OWNER_ANCHOR_AMBIGUOUS", "OWNER_ANCHOR_MISMATCH"
  ])]],
  ["E_PAGE_PROOF", ["PAGE_REJECTED", new Set([
    "PAGE_BVID_REJECTED", "PAGE_IDENTITY_REJECTED", "PAGE_ORIGIN_REJECTED", "PAGE_URL_REJECTED"
  ])]],
  ["E_PAGE_SCRIPT_TIMEOUT", ["SCRIPT_TIMEOUT", new Set(["SCRIPT_INVOCATION_FAILED"])]],
  ["E_PAGE_STABILITY_TIMEOUT", ["READY_UNSTABLE", new Set(["STABLE_SNAPSHOTS_PENDING"])]],
  ["E_PAGE_TAB_DRIFT", ["TAB_IDENTITY", new Set(["TAB_IDENTITY_DRIFT"])]],
  ["E_PAGE_VIDEO_ABSENT", ["VIDEO_ABSENT", new Set(["VIDEO_ELEMENT_ABSENT"])]],
]);
const PREPARELESS_REJECT_CODES = new Set(PREPARELESS_TERMINAL_DIAGNOSTIC_CONTRACT.keys());
const PAGE_PROOF_DEADLINE_MS = 60000;
const PAGE_EXTENSION_ACTIVATION_GRACE_MS = 5000;
const PAGE_PROOF_INVOCATION_TIMEOUT_MS = 5000;
const PAGE_PROOF_POLL_MS = 500;
const PAGE_PROOF_STABLE_SNAPSHOTS = 3;
const PAGE_PROOF_KEYS = [
  "bvid", "canonical_url", "creator_uid", "eme_present", "job_id", "observed_at_unix_ms",
  "metadata_source", "observed_duration_ms", "ready_state", "task_nonce", "video_height", "video_width"
];
const PAGE_PENDING_STATES = new Set([
  "DIMENSIONS_PENDING", "IDENTITY_PENDING", "METADATA_NOT_READY", "OWNER_PENDING", "VIDEO_ABSENT"
]);
const PAGE_DIAGNOSTIC_STATES = new Set([
  ...PAGE_PENDING_STATES, "PAGE_REJECTED", "READY_UNSTABLE", "SCRIPT_TIMEOUT", "TAB_IDENTITY"
]);
const PAGE_DIAGNOSTIC_REASONS = new Set([
  "DEADLINE_EXHAUSTED", "METADATA_FIELDS_PENDING", "OWNER_ANCHOR_ABSENT",
  "OWNER_ANCHOR_AMBIGUOUS", "OWNER_ANCHOR_MISMATCH",
  "INITIAL_STATE_ASSIGNMENT_ABSENT", "INITIAL_STATE_JSON_INVALID",
  "INITIAL_STATE_VIDEO_DATA_ABSENT",
  "PAGE_ACCESS_REJECTED", "PAGE_BVID_REJECTED", "PAGE_DOM_IDENTITY_PENDING",
  "PAGE_DRM_REJECTED", "PAGE_DURATION_REJECTED", "PAGE_IDENTITY_REJECTED",
  "PAGE_MULTIPART_REJECTED", "PAGE_NAVIGATION_PENDING", "PAGE_ORIGIN_REJECTED",
  "PAGE_OWNER_REJECTED", "PAGE_SCRIPTING_PENDING", "PAGE_TAB_ACTIVATION_PENDING",
  "PAGE_URL_PENDING", "PAGE_URL_REJECTED", "PAGE_VISIBILITY_PENDING",
  "PAGE_WINDOW_FOCUS_PENDING", "PAGE_WINDOW_MINIMIZED_PENDING", "PAGE_WINDOW_STATE_PENDING",
  "SCRIPT_INVOCATION_FAILED", "STABLE_SNAPSHOTS_PENDING",
  "TAB_IDENTITY_DRIFT", "VIDEO_DIMENSIONS_PENDING", "VIDEO_ELEMENT_ABSENT"
]);
const PAGE_METADATA_UNAVAILABLE_REASONS = new Set([
  "INITIAL_STATE_ASSIGNMENT_ABSENT", "INITIAL_STATE_JSON_INVALID",
  "INITIAL_STATE_VIDEO_DATA_ABSENT"
]);
const PAGE_PENDING_TERMINAL_CONTRACT = new Map([
  ["E_PAGE_DIMENSIONS_UNAVAILABLE", ["DIMENSIONS_PENDING", new Set(["VIDEO_DIMENSIONS_PENDING"])]],
  ["E_PAGE_IDENTITY_UNAVAILABLE", ["IDENTITY_PENDING", new Set([
    "PAGE_DOM_IDENTITY_PENDING", "PAGE_NAVIGATION_PENDING", "PAGE_SCRIPTING_PENDING",
    "PAGE_TAB_ACTIVATION_PENDING", "PAGE_URL_PENDING", "PAGE_VISIBILITY_PENDING",
    "PAGE_WINDOW_FOCUS_PENDING", "PAGE_WINDOW_MINIMIZED_PENDING", "PAGE_WINDOW_STATE_PENDING"
  ])]],
  ["E_PAGE_METADATA_NOT_READY", ["METADATA_NOT_READY", PAGE_METADATA_UNAVAILABLE_REASONS]],
  ["E_PAGE_OWNER_ANCHOR_UNAVAILABLE", ["OWNER_PENDING", new Set([
    "OWNER_ANCHOR_ABSENT", "OWNER_ANCHOR_AMBIGUOUS", "OWNER_ANCHOR_MISMATCH"
  ])]],
  ["E_PAGE_VIDEO_ABSENT", ["VIDEO_ABSENT", new Set(["VIDEO_ELEMENT_ABSENT"])]],
]);
const MAX_COOKIE_COUNT = 128;
const COOKIE_KEYS = [
  "domain", "expiration_unix", "host_only", "http_only", "name", "partition_key",
  "path", "same_site", "secure", "session", "store_id", "value"
];
const COOKIE_SAME_SITE = new Set(["no_restriction", "lax", "strict", "unspecified"]);
const COOKIE_CONTROL_RE = /\p{C}/u;
const STORE_ID_RE = /^[0-9]{1,8}$/;
const AUTH_COOKIE_NAME = "SESSDATA";
const REQUIRED_AUTH_COOKIE_NAMES = new Set([AUTH_COOKIE_NAME]);
const TRANSFER_COOKIE_NAMES = new Set([AUTH_COOKIE_NAME]);
const COOKIE_ACCESS_REASONS = new Set([
  "COOKIE_API_ERROR", "COOKIE_API_SHAPE", "COOKIE_AUTH_SET_EMPTY",
  "COOKIE_EQUAL_PRECEDENCE_CONFLICT",
  "COOKIE_RELEVANCE_AMBIGUOUS", "COOKIE_SELECTED_INVALID",
  "COOKIE_SELECTION_EXCEPTION", "COOKIE_TRANSFER_INVALID",
  "COOKIE_TRANSFER_OVERFLOW"
]);
let drainLease = false;
let lastDrainErrorCode = null;
let lastCookieAccessReason = null;
let lastTabDriftReason = null;
let lastPageReadinessDiagnostic = null;
let lastExtensionDiagnostic = null;
let lastBrowserLifecycleDiagnostic = null;

const BROWSER_LIFECYCLE_DIAGNOSTIC_CONTRACT = new Map([
  ["OWNED_TAB_RECORDED", "BROWSER_OWNERSHIP"],
  ["OWNED_TAB_ADOPTED", "BROWSER_OWNERSHIP"],
  ["OWNED_TAB_RECORD_INVALID", "BROWSER_OWNERSHIP"],
  ["OWNED_TAB_STORAGE_FAILED", "BROWSER_OWNERSHIP"],
  ["OWNED_TAB_CLOSED", "BROWSER_CLEANUP"],
  ["OWNED_TAB_ALREADY_CLOSED", "BROWSER_CLEANUP"],
  ["OWNED_TAB_IDENTITY_DRIFT", "BROWSER_CLEANUP"],
  ["OWNED_TAB_CLOSE_FAILED", "BROWSER_CLEANUP"],
  ["OWNED_TAB_AUTOPLAY_STOPPED", "BROWSER_CLEANUP"]
]);

const EXTENSION_DIAGNOSTIC_CONTRACT = new Map([
  ["DOCUMENT_FOCUS_FALSE", "SCRIPTING"],
  ["DOCUMENT_FOCUS_TRUE", "SCRIPTING"],
  ["DOCUMENT_FOCUS_UNAVAILABLE", "SCRIPTING"],
  ["NATIVE_CONNECT_FAILED", "NATIVE_MESSAGING"],
  ["NATIVE_DISCONNECT_FAILED", "NATIVE_MESSAGING"],
  ["SCRIPTING_EXECUTE_FAILED", "SCRIPTING"],
  ["SERVICE_WORKER_ERROR", "SERVICE_WORKER"],
  ["SERVICE_WORKER_UNHANDLED_REJECTION", "SERVICE_WORKER"],
  ["TABS_CREATE_FAILED", "TABS"],
  ["TABS_GET_FAILED", "TABS"],
  ["TABS_QUERY_FAILED", "TABS"],
  ["TABS_UPDATE_FAILED", "TABS"],
  ["WINDOWS_GET_FAILED", "WINDOWS"],
  ["WINDOWS_UPDATE_FAILED", "WINDOWS"],
  ["WINDOW_FOCUS_FALSE", "WINDOWS"],
  ["WINDOW_FOCUS_TRUE", "WINDOWS"],
  ["DOCUMENT_VISIBILITY_HIDDEN", "SCRIPTING"],
  ["DOCUMENT_VISIBILITY_VISIBLE", "SCRIPTING"],
  ["OS_FOREGROUND_LAUNCH_FAILED", "NATIVE_FOREGROUND"],
  ["OS_FOREGROUND_LOCKED", "NATIVE_FOREGROUND"],
  ["OS_FOREGROUND_PLATFORM_UNSUPPORTED", "NATIVE_FOREGROUND"],
  ["OS_FOREGROUND_READY", "NATIVE_FOREGROUND"],
  ["OS_FOREGROUND_REPLAY", "NATIVE_FOREGROUND"],
  ["OS_FOREGROUND_WINDOW_ABSENT", "NATIVE_FOREGROUND"],
  ["OS_FOREGROUND_WINDOW_AMBIGUOUS", "NATIVE_FOREGROUND"]
]);
const DOCUMENT_FOCUS_DIAGNOSTICS = new Set([
  "DOCUMENT_FOCUS_FALSE", "DOCUMENT_FOCUS_TRUE", "DOCUMENT_FOCUS_UNAVAILABLE"
]);
const DOCUMENT_VISIBILITY_DIAGNOSTICS = new Set([
  "DOCUMENT_VISIBILITY_HIDDEN", "DOCUMENT_VISIBILITY_VISIBLE"
]);
const FOREGROUND_ERROR_DIAGNOSTICS = new Map([
  ["E_FOREGROUND_LAUNCH_FAILED", "OS_FOREGROUND_LAUNCH_FAILED"],
  ["E_FOREGROUND_LOCKED", "OS_FOREGROUND_LOCKED"],
  ["E_FOREGROUND_PLATFORM_UNSUPPORTED", "OS_FOREGROUND_PLATFORM_UNSUPPORTED"],
  ["E_FOREGROUND_REPLAY", "OS_FOREGROUND_REPLAY"],
  ["E_FOREGROUND_WINDOW_ABSENT", "OS_FOREGROUND_WINDOW_ABSENT"],
  ["E_FOREGROUND_WINDOW_AMBIGUOUS", "OS_FOREGROUND_WINDOW_AMBIGUOUS"]
]);
const FOREGROUND_ELIGIBLE_CODES = new Set([
  "E_PAGE_DIMENSIONS_UNAVAILABLE", "E_PAGE_IDENTITY_UNAVAILABLE",
  "E_PAGE_METADATA_UNAVAILABLE", "E_PAGE_OWNER_ANCHOR_UNAVAILABLE",
  "E_PAGE_SCRIPT_TIMEOUT", "E_PAGE_STABILITY_TIMEOUT", "E_PAGE_VIDEO_ABSENT"
]);

function recordExtensionDiagnostic(reason) {
  const phase = EXTENSION_DIAGNOSTIC_CONTRACT.get(reason);
  if (typeof phase !== "string") return;
  lastExtensionDiagnostic = Object.freeze({phase, reason});
}

function recordBrowserLifecycleDiagnostic(reason) {
  const phase = BROWSER_LIFECYCLE_DIAGNOSTIC_CONTRACT.get(reason);
  if (typeof phase !== "string") return;
  lastBrowserLifecycleDiagnostic = Object.freeze({phase, reason});
}

function exactOwnedTabRecord(value) {
  const keys = [
    "schema", "job_id", "lease_id", "bvid", "tab_id", "window_id", "cookie_store_id"
  ];
  if (!isPlainObject(value) || !exactKeys(value, keys) || value.schema !== OWNED_TAB_SCHEMA ||
      !HEX64_RE.test(value.job_id || "") || !HEX32_RE.test(value.lease_id || "") ||
      !BVID_RE.test(value.bvid || "") || !Number.isInteger(value.tab_id) || value.tab_id < 0 ||
      !Number.isInteger(value.window_id) || value.window_id < 0 ||
      !STORE_ID_RE.test(value.cookie_store_id || "")) return null;
  return Object.freeze({...value});
}

async function storageSessionCall(methodName, args) {
  if (!chrome.storage?.session) throw new Error("E_OWNED_TAB_STORAGE");
  return chromeApiCall(
    chrome.storage.session, methodName, args,
    "E_OWNED_TAB_STORAGE", "OWNED_TAB_STORAGE_FAILED"
  );
}

async function loadOwnedTabRecord() {
  try {
    const value = await storageSessionCall("get", [OWNED_TAB_STORAGE_KEY]);
    const raw = isPlainObject(value) ? value[OWNED_TAB_STORAGE_KEY] : null;
    if (raw === undefined || raw === null) return null;
    const record = exactOwnedTabRecord(raw);
    if (record !== null) return record;
    recordBrowserLifecycleDiagnostic("OWNED_TAB_RECORD_INVALID");
    await storageSessionCall("remove", [OWNED_TAB_STORAGE_KEY]);
  } catch {
    recordBrowserLifecycleDiagnostic("OWNED_TAB_STORAGE_FAILED");
  }
  return null;
}

async function persistOwnedTabRecord(job, leaseId, binding) {
  const record = exactOwnedTabRecord({
    schema: OWNED_TAB_SCHEMA, job_id: job.job_id, lease_id: leaseId, bvid: job.bvid,
    tab_id: binding.tabId, window_id: binding.windowId, cookie_store_id: binding.cookieStoreId
  });
  if (record === null || binding.managed !== true) throw new Error("E_OWNED_TAB_STORAGE");
  try {
    await storageSessionCall("set", [{[OWNED_TAB_STORAGE_KEY]: record}]);
  } catch {
    recordBrowserLifecycleDiagnostic("OWNED_TAB_STORAGE_FAILED");
    throw new Error("E_OWNED_TAB_STORAGE");
  }
  recordBrowserLifecycleDiagnostic("OWNED_TAB_RECORDED");
  return record;
}

async function clearOwnedTabRecord() {
  try {
    await storageSessionCall("remove", [OWNED_TAB_STORAGE_KEY]);
    return true;
  } catch {
    recordBrowserLifecycleDiagnostic("OWNED_TAB_STORAGE_FAILED");
    return false;
  }
}

async function cleanupOwnedTab(recordValue = null) {
  const record = exactOwnedTabRecord(recordValue) || await loadOwnedTabRecord();
  if (record === null) return true;
  let tab;
  try {
    tab = await chromeApiCall(
      chrome.tabs, "get", [record.tab_id], "E_OWNED_TAB_CLOSE", "TABS_GET_FAILED"
    );
  } catch {
    await clearOwnedTabRecord();
    recordBrowserLifecycleDiagnostic("OWNED_TAB_ALREADY_CLOSED");
    return true;
  }
  if (!isPlainObject(tab) || tab.id !== record.tab_id || tab.windowId !== record.window_id ||
      String(tab.cookieStoreId ?? "0") !== record.cookie_store_id ||
      (!locationMatches(tab.url, record.bvid) && !locationMatches(tab.pendingUrl, record.bvid) &&
       !isManagedIdentityPendingUrl(tab.url, record.bvid))) {
    await clearOwnedTabRecord();
    recordBrowserLifecycleDiagnostic("OWNED_TAB_IDENTITY_DRIFT");
    return false;
  }
  // Retire the durable ownership capability before the non-atomic remove. A
  // failed remove must never leave a record that a restarted service worker
  // could apply to a same-id/same-BVID user replacement.
  if (!await clearOwnedTabRecord()) {
    recordBrowserLifecycleDiagnostic("OWNED_TAB_CLOSE_FAILED");
    return false;
  }
  try {
    await chromeApiCall(
      chrome.tabs, "remove", [record.tab_id], "E_OWNED_TAB_CLOSE", "TABS_REMOVE_FAILED"
    );
    recordBrowserLifecycleDiagnostic("OWNED_TAB_CLOSED");
    return true;
  } catch {
    // tabs.remove is not an atomic compare-and-close operation. Once it fails,
    // the numeric tab id may already name a replacement user tab, including a
    // replacement on the same BVID. No subsequent tabs.update/remove mutation
    // can prove object ownership. The durable capability was already retired,
    // so surface only a fixed, sanitized lifecycle result and never retry it.
    recordBrowserLifecycleDiagnostic("OWNED_TAB_CLOSE_FAILED");
    return false;
  }
}

function extensionApiError(code, reason) {
  recordExtensionDiagnostic(reason);
  return new Error(code);
}

function chromeApiCall(receiver, methodName, args, code, reason) {
  return new Promise((resolve, reject) => {
    let settled = false;
    const settle = (error, value) => {
      if (settled) return;
      settled = true;
      if (error) reject(extensionApiError(code, reason)); else resolve(value);
    };
    const callback = value => {
      let failed = false;
      try { failed = chrome.runtime.lastError != null; } catch { failed = true; }
      settle(failed, value);
    };
    let returned;
    try {
      returned = receiver[methodName](...args, callback);
    } catch {
      settle(true);
      return;
    }
    if (returned && typeof returned.then === "function") {
      returned.then(value => settle(false, value), () => settle(true));
    }
  });
}

if (typeof globalThis.addEventListener === "function") {
  globalThis.addEventListener("error", () => recordExtensionDiagnostic("SERVICE_WORKER_ERROR"));
  globalThis.addEventListener("unhandledrejection", () =>
    recordExtensionDiagnostic("SERVICE_WORKER_UNHANDLED_REJECTION"));
}

function isPlainObject(value) {
  if (value === null || typeof value !== "object" || Array.isArray(value)) return false;
  const prototype = Object.getPrototypeOf(value);
  return prototype === Object.prototype || prototype === null;
}

function exactKeys(value, keys) {
  return isPlainObject(value) && Object.keys(value).sort().join("\0") === [...keys].sort().join("\0");
}

function safeErrorCode(error, fallback = "E_EXTENSION") {
  const candidate = typeof error?.message === "string" ? error.message : "";
  return ERROR_CODE_RE.test(candidate) ? candidate : fallback;
}

function canonicalUrl(bvid) {
  return `https://www.bilibili.com/video/${bvid}`;
}

function locationMatches(rawUrl, bvid) {
  if (!BVID_RE.test(bvid) || typeof rawUrl !== "string") return false;
  let parsed;
  try { parsed = new URL(rawUrl); } catch { return false; }
  const path = `/video/${bvid}`;
  return parsed.origin === "https://www.bilibili.com" &&
    (parsed.pathname === path || parsed.pathname === `${path}/`) &&
    (parsed.search === "" || /^\?vd_source=[0-9a-f]{32}$/.test(parsed.search)) &&
    parsed.hash === "";
}

function isManagedIdentityPendingUrl(rawUrl, bvid) {
  if (rawUrl === "about:blank") return true;
  if (typeof rawUrl !== "string" || !BVID_RE.test(bvid)) return false;
  let parsed;
  try { parsed = new URL(rawUrl); } catch { return true; }
  if (parsed.origin !== "https://www.bilibili.com") return false;
  const videoMatch = /^\/video\/(BV1[1-9A-HJ-NP-Za-km-z]{9})\/?$/.exec(parsed.pathname);
  return videoMatch === null || videoMatch[1] === bvid;
}

function durationToleranceMs(expected) {
  return Math.max(1500, Math.min(10000, Math.ceil(expected / 1000)));
}

async function sha256Hex(text) {
  const digest = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(text));
  return Array.from(new Uint8Array(digest), value => value.toString(16).padStart(2, "0")).join("");
}

async function validateJob(job) {
  const successor = isPlainObject(job) && Object.prototype.hasOwnProperty.call(job, "lineage");
  if (!exactKeys(job, successor ? [...JOB_KEYS, "lineage"] : JOB_KEYS) || !HEX64_RE.test(job.job_id) || !BVID_RE.test(job.bvid) ||
      !CREATOR_RE.test(job.creator_uid) || job.canonical_url !== canonicalUrl(job.bvid) ||
      !Number.isSafeInteger(job.expected_duration_ms) || job.expected_duration_ms < 1000 ||
      job.expected_duration_ms > 86400000 || typeof job.title !== "string" || !job.title.trim() ||
      new TextEncoder().encode(job.title).length > 600 || typeof job.published_at !== "string" ||
      job.published_at.length > 64 || !Number.isFinite(Date.parse(job.published_at))) return false;
  let stable;
  if (successor) {
    const lineage = job.lineage;
    if (!exactKeys(lineage, LINEAGE_KEYS) || !HEX64_RE.test(lineage.predecessor_job_id) ||
        !Number.isSafeInteger(lineage.retry_generation) || lineage.retry_generation < 1 ||
        lineage.retry_generation > 1000000 || !ERROR_CODE_RE.test(lineage.predecessor_terminal_error_code) ||
        !MESSAGE_ID_RE.test(lineage.authorization_message_id) ||
        !HANDOFF_ID_RE.test(lineage.authorization_handoff_id) ||
        !UPPER_HEX64_RE.test(lineage.authorization_sha256) ||
        !MESSAGE_ID_RE.test(lineage.repair_review_result_message_id) ||
        !AUDIT_ID_RE.test(lineage.repair_audit_id) ||
        !Number.isSafeInteger(lineage.repair_audit_bytes) || lineage.repair_audit_bytes < 1 ||
        !UPPER_HEX64_RE.test(lineage.repair_audit_sha256)) return false;
    stable = await sha256Hex([
      "bili-auth-job-v2", job.creator_uid, job.bvid, lineage.predecessor_job_id,
      String(lineage.retry_generation), lineage.predecessor_terminal_error_code,
      lineage.authorization_message_id, lineage.authorization_handoff_id,
      lineage.authorization_sha256, lineage.repair_review_result_message_id,
      lineage.repair_audit_id, String(lineage.repair_audit_bytes), lineage.repair_audit_sha256
    ].join("\0"));
  } else {
    stable = await sha256Hex(`bili-auth-job-v1\0${job.creator_uid}\0${job.bvid}`);
  }
  return stable === job.job_id;
}

function validateMaintenance(value) {
  return exactKeys(value, ["reload_required", "reload_token", "required_extension_build", "retry_after_unix_ms"]) &&
    typeof value.required_extension_build === "string" && value.required_extension_build.length <= 128 &&
    typeof value.reload_required === "boolean" &&
    (value.reload_token === null || HEX32_RE.test(value.reload_token)) &&
    Number.isSafeInteger(value.retry_after_unix_ms) && value.retry_after_unix_ms >= 0;
}

async function validateResponse(value, expectedType) {
  if (!exactKeys(value, RESPONSE_KEYS) || value.schema !== SCHEMA || value.type !== expectedType ||
      typeof value.host_build !== "string" || !SAFE_PHASES.has(value.phase) ||
      !Number.isInteger(value.progress) || value.progress < 0 || value.progress > 100 ||
      (value.error_code !== null && !/^E_[A-Z0-9_]{1,48}$/.test(value.error_code)) ||
      !validateMaintenance(value.maintenance)) return false;
  if (value.job !== null && !(await validateJob(value.job))) return false;
  if (value.lease_id !== null && !HEX32_RE.test(value.lease_id)) return false;
  for (const name of ["formal_filename", "mapping_filename", "prepare_id"]) {
    if (value[name] !== null && typeof value[name] !== "string") return false;
  }
  return true;
}

function nativeSession() {
  let port;
  try {
    port = chrome.runtime.connectNative(HOST_NAME);
  } catch {
    throw extensionApiError("E_HOST_CONNECT", "NATIVE_CONNECT_FAILED");
  }
  if (!isPlainObject(port) && (port === null || typeof port !== "object")) {
    throw extensionApiError("E_HOST_CONNECT", "NATIVE_CONNECT_FAILED");
  }
  const messages = [];
  const waiters = [];
  let disconnected = false;
  let closeRequested = false;
  let lastDeterministicError = null;
  const rejectWaiters = code => {
    while (waiters.length) {
      const waiter = waiters.shift();
      clearTimeout(waiter.timer);
      waiter.reject(new Error(code));
    }
  };
  port.onMessage.addListener(message => {
    if (isPlainObject(message) && ERROR_CODE_RE.test(message.error_code || "")) {
      lastDeterministicError = message.error_code;
    }
    const waiter = waiters.shift();
    if (waiter) {
      clearTimeout(waiter.timer);
      waiter.resolve(message);
    } else messages.push(message);
  });
  port.onDisconnect.addListener(() => {
    if (disconnected) return;
    disconnected = true;
    let runtimeFailure = false;
    try { runtimeFailure = chrome.runtime.lastError != null; } catch { runtimeFailure = true; }
    if (runtimeFailure) recordExtensionDiagnostic("NATIVE_DISCONNECT_FAILED");
    rejectWaiters(lastDeterministicError || "E_HOST_DISCONNECT");
  });
  const next = timeoutMs => new Promise((resolve, reject) => {
    if (messages.length) { resolve(messages.shift()); return; }
    if (disconnected) { reject(new Error(lastDeterministicError || "E_HOST_DISCONNECT")); return; }
    const waiter = {resolve, reject, timer: null};
    waiters.push(waiter);
    waiter.timer = setTimeout(() => {
      const index = waiters.indexOf(waiter);
      if (index >= 0) {
        waiters.splice(index, 1);
        reject(new Error("E_HOST_TIMEOUT"));
      }
    }, timeoutMs);
  });
  return {
    async send(message, timeoutMs = 20000) {
      if (disconnected) throw new Error(lastDeterministicError || "E_HOST_DISCONNECT");
      const response = next(timeoutMs);
      try {
        port.postMessage(message);
      } catch (error) {
        rejectWaiters(safeErrorCode(error, "E_HOST_SEND"));
      }
      return response;
    },
    disconnect() {
      if (closeRequested) return;
      closeRequested = true;
      if (!disconnected) {
        try { port.disconnect(); } catch {}
      }
    }
  };
}

function randomHex(bytes) {
  const data = new Uint8Array(bytes);
  crypto.getRandomValues(data);
  return Array.from(data, value => value.toString(16).padStart(2, "0")).join("");
}

function isPageReadinessDiagnostic(value) {
  return exactKeys(value, ["attempts", "elapsed_ms", "reason", "state"]) &&
    Number.isInteger(value.attempts) && value.attempts >= 0 && value.attempts <= 10000 &&
    Number.isInteger(value.elapsed_ms) && value.elapsed_ms >= 0 && value.elapsed_ms <= 7200000 &&
    PAGE_DIAGNOSTIC_STATES.has(value.state) && PAGE_DIAGNOSTIC_REASONS.has(value.reason);
}

function isCanonicalPreparelessTerminal(code, diagnostic) {
  if (!isPageReadinessDiagnostic(diagnostic)) return false;
  const contract = PREPARELESS_TERMINAL_DIAGNOSTIC_CONTRACT.get(code);
  return Array.isArray(contract) && contract.length === 2 && diagnostic.state === contract[0] &&
    contract[1] instanceof Set && contract[1].has(diagnostic.reason);
}

function pageReadinessError(code, attempts, startedAtUnixMs, state, reason) {
  const diagnostic = {
    attempts,
    elapsed_ms: Math.max(0, Math.min(7200000, Date.now() - startedAtUnixMs)),
    state,
    reason
  };
  if (!isCanonicalPreparelessTerminal(code, diagnostic)) return new Error("E_REJECT");
  lastPageReadinessDiagnostic = diagnostic;
  const error = new Error(code);
  error.page_readiness_diagnostic = diagnostic;
  return error;
}

function fallbackPageReadinessDiagnostic(code) {
  const contract = PREPARELESS_TERMINAL_DIAGNOSTIC_CONTRACT.get(code);
  if (!Array.isArray(contract) || contract.length !== 2 || !(contract[1] instanceof Set) ||
      contract[1].size !== 1) return null;
  const value = {attempts: 0, elapsed_ms: 0, state: contract[0], reason: [...contract[1]][0]};
  lastPageReadinessDiagnostic = value;
  return value;
}

function tabDriftError(reason) {
  lastTabDriftReason = reason;
  const error = new Error("E_PAGE_TAB_DRIFT");
  error.reason_code = reason;
  return error;
}

function tabIdentityReason(tab, binding) {
  if (!isPlainObject(tab) || !Number.isInteger(tab.id)) return "TAB_ID_INVALID";
  if (tab.id !== binding.tabId) return "TAB_ID_CHANGED";
  if (!Number.isInteger(tab.windowId) || tab.windowId !== binding.windowId) return "TAB_WINDOW_CHANGED";
  if (String(tab.cookieStoreId ?? "0") !== binding.cookieStoreId) return "TAB_STORE_CHANGED";
  return null;
}

function bindTab(tab, bvid, managed) {
  if (!isPlainObject(tab) || !Number.isInteger(tab.id) || !Number.isInteger(tab.windowId)) {
    throw tabDriftError("TAB_IDENTITY_INVALID");
  }
  const exactUrl = locationMatches(tab.url, bvid);
  const exactPendingUrl = managed === true && locationMatches(tab.pendingUrl, bvid);
  if (!exactUrl && !exactPendingUrl) throw tabDriftError("TAB_URL_UNBOUND");
  return Object.freeze({
    tabId: tab.id,
    windowId: tab.windowId,
    cookieStoreId: String(tab.cookieStoreId ?? "0"),
    managed: managed === true
  });
}

async function revalidateBoundTab(binding, bvid) {
  let current;
  try {
    current = await chromeApiCall(
      chrome.tabs, "get", [binding.tabId], "E_PAGE_TAB_DRIFT", "TABS_GET_FAILED"
    );
  } catch {
    throw tabDriftError("TAB_REMOVED_OR_UNAVAILABLE");
  }
  const identityReason = tabIdentityReason(current, binding);
  if (identityReason !== null) throw tabDriftError(identityReason);
  if (!locationMatches(current.url, bvid)) throw tabDriftError("TAB_URL_CHANGED");
  return current;
}

async function activateBoundTab(binding, tab, bvid, startedAtUnixMs) {
  const identityReason = tabIdentityReason(tab, binding);
  if (identityReason !== null) throw tabDriftError(identityReason);
  let focusedWindow;
  try {
    focusedWindow = await chromeApiCall(
      chrome.windows, "update", [binding.windowId, {state: "normal", focused: true}],
      "E_PAGE_IDENTITY_UNAVAILABLE", "WINDOWS_UPDATE_FAILED"
    );
  } catch {
    throw pageReadinessError(
      "E_PAGE_IDENTITY_UNAVAILABLE", 0, startedAtUnixMs,
      "IDENTITY_PENDING", "PAGE_WINDOW_FOCUS_PENDING"
    );
  }
  if (!isPlainObject(focusedWindow) || focusedWindow.id !== binding.windowId) {
    throw tabDriftError("TAB_WINDOW_CHANGED");
  }
  let updated;
  try {
    updated = await chromeApiCall(
      chrome.tabs, "update", [binding.tabId, {active: true}],
      "E_PAGE_IDENTITY_UNAVAILABLE", "TABS_UPDATE_FAILED"
    );
  } catch {
    throw pageReadinessError(
      "E_PAGE_IDENTITY_UNAVAILABLE", 0, startedAtUnixMs,
      "IDENTITY_PENDING", "PAGE_TAB_ACTIVATION_PENDING"
    );
  }
  const updatedIdentityReason = tabIdentityReason(updated, binding);
  if (updatedIdentityReason !== null) throw tabDriftError(updatedIdentityReason);
  if (!locationMatches(updated.url, bvid) &&
      !(binding.managed && (locationMatches(updated.pendingUrl, bvid) ||
        isManagedIdentityPendingUrl(updated.url, bvid)))) {
    throw tabDriftError("TAB_MANAGED_URL_DRIFT");
  }
  return updated;
}

async function waitForComplete(binding, tab, bvid, startedAtUnixMs, deadlineUnixMs) {
  const identityReason = tabIdentityReason(tab, binding);
  if (identityReason !== null) throw tabDriftError(identityReason);
  if (tab.status === "complete" && locationMatches(tab.url, bvid)) {
    return revalidateBoundTab(binding, bvid);
  }
  if (!locationMatches(tab.url, bvid) &&
      !(binding.managed && (locationMatches(tab.pendingUrl, bvid) ||
        isManagedIdentityPendingUrl(tab.url, bvid)))) {
    throw tabDriftError("TAB_URL_UNBOUND");
  }
  return new Promise((resolve, reject) => {
    let done = false;
    let timer = null;
    const finish = (error, value) => {
      if (done) return;
      done = true;
      chrome.tabs.onUpdated.removeListener(onUpdated);
      chrome.tabs.onRemoved.removeListener(onRemoved);
      if (timer !== null) clearTimeout(timer);
      if (error) reject(error); else resolve(value);
    };
    const onUpdated = (tabId, change, current) => {
      if (tabId !== binding.tabId) return;
      const currentIdentityReason = tabIdentityReason(current, binding);
      if (currentIdentityReason !== null) {
        finish(tabDriftError(currentIdentityReason));
        return;
      }
      if (typeof change?.url === "string" && !locationMatches(change.url, bvid) &&
          !(binding.managed && isManagedIdentityPendingUrl(change.url, bvid))) {
        finish(tabDriftError("TAB_MANAGED_URL_DRIFT"));
        return;
      }
      if (locationMatches(current.url, bvid) && current.status === "complete") {
        finish(null, current);
        return;
      }
      if (!locationMatches(current.url, bvid) &&
          !(binding.managed && (locationMatches(current.pendingUrl, bvid) ||
            isManagedIdentityPendingUrl(current.url, bvid)))) {
        finish(tabDriftError("TAB_URL_CHANGED"));
      }
    };
    const onRemoved = tabId => {
      if (tabId === binding.tabId) finish(tabDriftError("TAB_REMOVED_OR_UNAVAILABLE"));
    };
    chrome.tabs.onUpdated.addListener(onUpdated);
    chrome.tabs.onRemoved.addListener(onRemoved);
    timer = setTimeout(() => finish(pageReadinessError(
      "E_PAGE_IDENTITY_UNAVAILABLE", 0, startedAtUnixMs,
      "IDENTITY_PENDING", "PAGE_URL_PENDING"
    )), Math.max(1, deadlineUnixMs - Date.now()));
  });
}

async function waitForActiveNonMinimizedBoundTab(binding, bvid, startedAtUnixMs, deadlineUnixMs) {
  let pendingReason = "PAGE_WINDOW_STATE_PENDING";
  while (Date.now() < deadlineUnixMs) {
    const current = await revalidateBoundTab(binding, bvid);
    let currentWindow;
    try {
      currentWindow = await chromeApiCall(
        chrome.windows, "get", [binding.windowId],
        "E_PAGE_IDENTITY_UNAVAILABLE", "WINDOWS_GET_FAILED"
      );
    } catch {
      currentWindow = null;
    }
    if (!isPlainObject(currentWindow) || currentWindow.id !== binding.windowId) {
      pendingReason = "PAGE_WINDOW_STATE_PENDING";
    } else if (typeof currentWindow.state !== "string") {
      pendingReason = "PAGE_WINDOW_STATE_PENDING";
    } else if (currentWindow.state === "minimized") {
      pendingReason = "PAGE_WINDOW_MINIMIZED_PENDING";
    } else if (!["normal", "maximized", "fullscreen", "locked-fullscreen"].includes(currentWindow.state)) {
      pendingReason = "PAGE_WINDOW_STATE_PENDING";
    } else if (current.active !== true) {
      pendingReason = "PAGE_TAB_ACTIVATION_PENDING";
    } else {
      recordExtensionDiagnostic(currentWindow.focused === true ?
        "WINDOW_FOCUS_TRUE" : "WINDOW_FOCUS_FALSE");
      return current;
    }
    const remainingMs = deadlineUnixMs - Date.now();
    if (remainingMs <= 0) break;
    await new Promise(resolve => setTimeout(resolve, Math.min(PAGE_PROOF_POLL_MS, remainingMs)));
  }
  throw pageReadinessError(
    "E_PAGE_IDENTITY_UNAVAILABLE", 0, startedAtUnixMs,
    "IDENTITY_PENDING", pendingReason
  );
}

function foregroundFallbackEligible(error) {
  return FOREGROUND_ELIGIBLE_CODES.has(error?.message) &&
    isPageReadinessDiagnostic(error?.page_readiness_diagnostic);
}

function exactWindowBounds(value) {
  if (!isPlainObject(value)) return null;
  const bounds = {};
  for (const key of ["left", "top", "width", "height"]) {
    if (!Number.isSafeInteger(value[key])) return null;
    bounds[key] = value[key];
  }
  if (bounds.width < 1 || bounds.height < 1) return null;
  return bounds;
}

async function foregroundAndRebind(session, job, leaseId, selected, flow, sourceError) {
  if (flow.foregroundUsed) throw sourceError;
  flow.foregroundUsed = true;
  let windowValue;
  try {
    windowValue = await chromeApiCall(
      chrome.windows, "get", [selected.binding.windowId],
      "E_PAGE_IDENTITY_UNAVAILABLE", "WINDOWS_GET_FAILED"
    );
  } catch {
    throw sourceError;
  }
  const windowBounds = exactWindowBounds(windowValue);
  if (windowBounds === null) throw sourceError;
  const response = await session.send({
    schema: SCHEMA, type: "foreground", job_id: job.job_id, lease_id: leaseId,
    tab_id: selected.binding.tabId, window_id: selected.binding.windowId,
    window_bounds: windowBounds
  }, 20000);
  if (!(await validateResponse(response, "foreground")) ||
      response.job?.job_id !== job.job_id || response.lease_id !== leaseId) {
    throw sourceError;
  }
  if (response.phase !== "READY" || response.error_code !== null) {
    const diagnosticReason = FOREGROUND_ERROR_DIAGNOSTICS.get(response.error_code);
    if (typeof diagnosticReason === "string") recordExtensionDiagnostic(diagnosticReason);
    throw sourceError;
  }
  recordExtensionDiagnostic("OS_FOREGROUND_READY");
  let pendingError = sourceError;
  while (Date.now() < flow.deadlineUnixMs) {
    let tabs;
    try {
      tabs = await chromeApiCall(
        chrome.tabs, "query", [{url: ["https://www.bilibili.com/video/*"], windowType: "normal"}],
        "E_PAGE_IDENTITY_UNAVAILABLE", "TABS_QUERY_FAILED"
      );
    } catch {
      tabs = null;
    }
    if (Array.isArray(tabs)) {
      const exactCandidates = tabs.filter(item =>
        item?.incognito !== true && locationMatches(item?.url, job.bvid));
      if (exactCandidates.length > 1) throw new Error("E_PAGE_DUPLICATE_TAB");
      if (exactCandidates.length === 1) {
        const preservesOwnership = selected.binding.managed === true &&
          exactCandidates[0].id === selected.binding.tabId &&
          exactCandidates[0].windowId === selected.binding.windowId;
        const rebound = {
          binding: bindTab(exactCandidates[0], job.bvid, preservesOwnership), tab: exactCandidates[0]
        };
        const active = await waitForActiveNonMinimizedBoundTab(
          rebound.binding, job.bvid, flow.startedAtUnixMs, flow.deadlineUnixMs
        );
        return {binding: rebound.binding, tab: active, activeNonMinimized: active};
      }
      pendingError = pageReadinessError(
        "E_PAGE_IDENTITY_UNAVAILABLE", 0, flow.startedAtUnixMs,
        "IDENTITY_PENDING", "PAGE_URL_PENDING"
      );
    }
    const remainingMs = flow.deadlineUnixMs - Date.now();
    if (remainingMs <= 0) break;
    await new Promise(resolve => setTimeout(resolve, Math.min(PAGE_PROOF_POLL_MS, remainingMs)));
  }
  throw pendingError;
}

async function targetTab(session, job, leaseId, flow) {
  const startedAtUnixMs = Date.now();
  let tabs;
  try {
    tabs = await chromeApiCall(
      chrome.tabs, "query", [{
        url: ["https://www.bilibili.com/video/*"], windowType: "normal"
      }], "E_PAGE_IDENTITY_UNAVAILABLE", "TABS_QUERY_FAILED"
    );
  } catch {
    throw pageReadinessError(
      "E_PAGE_IDENTITY_UNAVAILABLE", 0, startedAtUnixMs,
      "IDENTITY_PENDING", "PAGE_DOM_IDENTITY_PENDING"
    );
  }
  if (!Array.isArray(tabs)) throw new Error("E_PAGE_PROOF");
  const storedOwnership = await loadOwnedTabRecord();
  const exactCandidates = [];
  for (const candidate of tabs.filter(item => item?.incognito !== true && locationMatches(item?.url, job.bvid))) {
    const adopted = storedOwnership !== null && storedOwnership.job_id === job.job_id &&
      storedOwnership.lease_id === leaseId && storedOwnership.bvid === job.bvid &&
      storedOwnership.tab_id === candidate.id && storedOwnership.window_id === candidate.windowId &&
      storedOwnership.cookie_store_id === String(candidate.cookieStoreId ?? "0");
    const provisional = bindTab(candidate, job.bvid, adopted);
    const current = await revalidateBoundTab(provisional, job.bvid);
    exactCandidates.push({binding: bindTab(current, job.bvid, adopted), tab: current});
    if (adopted) recordBrowserLifecycleDiagnostic("OWNED_TAB_ADOPTED");
  }
  if (exactCandidates.length > 1) throw new Error("E_PAGE_DUPLICATE_TAB");
  let selected;
  if (exactCandidates.length === 1) {
    selected = exactCandidates[0];
  } else {
    let created;
    try {
      created = await chromeApiCall(
        chrome.tabs, "create", [{url: canonicalUrl(job.bvid), active: false}],
        "E_PAGE_IDENTITY_UNAVAILABLE", "TABS_CREATE_FAILED"
      );
    } catch {
      throw pageReadinessError(
        "E_PAGE_IDENTITY_UNAVAILABLE", 0, startedAtUnixMs,
        "IDENTITY_PENDING", "PAGE_NAVIGATION_PENDING"
      );
    }
    selected = {binding: bindTab(created, job.bvid, true), tab: created};
    await persistOwnedTabRecord(job, leaseId, selected.binding);
  }
  try {
    const activated = await activateBoundTab(
      selected.binding, selected.tab, job.bvid, startedAtUnixMs
    );
    const activationDeadline = Math.min(
      flow.deadlineUnixMs, Date.now() + PAGE_EXTENSION_ACTIVATION_GRACE_MS
    );
    const ready = await waitForComplete(
      selected.binding, activated, job.bvid, startedAtUnixMs, activationDeadline
    );
    const activeNonMinimized = await waitForActiveNonMinimizedBoundTab(
      selected.binding, job.bvid, startedAtUnixMs, activationDeadline
    );
    return {binding: selected.binding, tab: ready, activeNonMinimized};
  } catch (error) {
    if (!foregroundFallbackEligible(error)) throw error;
    return foregroundAndRebind(session, job, leaseId, selected, flow, error);
  }
}

async function acquirePageProof(session, job, leaseId, selected, flow) {
  const remainingMs = flow.deadlineUnixMs - Date.now();
  if (remainingMs <= 0) {
    throw pageReadinessError(
      "E_PAGE_IDENTITY_UNAVAILABLE", 0, flow.startedAtUnixMs,
      "IDENTITY_PENDING", "PAGE_URL_PENDING"
    );
  }
  const initialBudgetMs = flow.foregroundUsed ? remainingMs :
    Math.min(PAGE_EXTENSION_ACTIVATION_GRACE_MS, remainingMs);
  try {
    return await observe(job, selected.binding, initialBudgetMs);
  } catch (error) {
    if (flow.foregroundUsed || !foregroundFallbackEligible(error)) throw error;
    const rebound = await foregroundAndRebind(session, job, leaseId, selected, flow, error);
    const finalBudgetMs = flow.deadlineUnixMs - Date.now();
    if (finalBudgetMs <= 0) throw error;
    return observe(job, rebound.binding, finalBudgetMs);
  }
}

function injectedObservation(job, taskNonce) {
  const path = `/video/${job.bvid}`;
  if (location.href === "about:blank" ||
      (typeof document.readyState === "string" && document.readyState !== "complete")) {
    return {status: "PENDING", terminal_error_code: "E_PAGE_IDENTITY_UNAVAILABLE",
      state: "IDENTITY_PENDING", reason: "PAGE_URL_PENDING"};
  }
  const documentVisibilityDiagnostic = document.visibilityState === "visible" ?
    "DOCUMENT_VISIBILITY_VISIBLE" : "DOCUMENT_VISIBILITY_HIDDEN";
  const documentFocusDiagnostic = typeof document.hasFocus !== "function" ?
    "DOCUMENT_FOCUS_UNAVAILABLE" :
    (document.hasFocus() === true ? "DOCUMENT_FOCUS_TRUE" : "DOCUMENT_FOCUS_FALSE");
  if (location.origin !== "https://www.bilibili.com") {
    return {status: "REJECT", error_code: "E_PAGE_PROOF",
      state: "PAGE_REJECTED", reason: "PAGE_ORIGIN_REJECTED"};
  }
  const observedBvid = /^\/video\/(BV1[1-9A-HJ-NP-Za-km-z]{9})\/?$/.exec(location.pathname)?.[1] ?? null;
  if (observedBvid !== null && observedBvid !== job.bvid) {
    return {status: "REJECT", error_code: "E_PAGE_PROOF",
      state: "PAGE_REJECTED", reason: "PAGE_BVID_REJECTED"};
  }
  if ((location.pathname !== path && location.pathname !== `${path}/`) ||
      (location.search !== "" && !/^\?vd_source=[0-9a-f]{32}$/.test(location.search)) ||
      location.hash !== "") {
    return {status: "REJECT", error_code: "E_PAGE_PROOF",
      state: "PAGE_REJECTED", reason: "PAGE_URL_REJECTED"};
  }
  if (document.querySelectorAll(
    ".error-container,.error-body,[data-bili-access-state='denied']"
  ).length > 0) {
    return {status: "REJECT", error_code: "E_PAGE_ACCESS_CONTROL",
      state: "PAGE_REJECTED", reason: "PAGE_ACCESS_REJECTED"};
  }
  const videos = Array.from(document.querySelectorAll("video"));
  if (videos.length === 0) return {status: "PENDING", terminal_error_code: "E_PAGE_VIDEO_ABSENT",
    state: "VIDEO_ABSENT", reason: "VIDEO_ELEMENT_ABSENT"};
  if (videos.length > 1) return {status: "REJECT", error_code: "E_MULTI_PART",
    state: "PAGE_REJECTED", reason: "PAGE_MULTIPART_REJECTED"};
  const video = videos[0];
  if (video.mediaKeys !== null) return {status: "REJECT", error_code: "E_DRM",
    state: "PAGE_REJECTED", reason: "PAGE_DRM_REJECTED"};
  let initialVideo = null;
  let initialStateReason = "INITIAL_STATE_ASSIGNMENT_ABSENT";
  for (const script of Array.from(document.querySelectorAll("script"))) {
    const raw = script?.textContent;
    if (typeof raw !== "string" || raw.length < 30 || raw.length > 2_000_000) continue;
    const trimmed = raw.trim();
    const assignment = /^window\.__INITIAL_STATE__\s*=\s*/.exec(trimmed);
    if (assignment === null) continue;
    initialStateReason = "INITIAL_STATE_JSON_INVALID";
    let encoded = trimmed.slice(assignment[0].length);
    const runtimeMarker = encoded.lastIndexOf(";(function(){");
    if (runtimeMarker >= 0) encoded = encoded.slice(0, runtimeMarker);
    else if (encoded.endsWith(";")) encoded = encoded.slice(0, -1);
    try {
      const parsed = JSON.parse(encoded);
      const candidate = parsed?.videoData;
      initialStateReason = "INITIAL_STATE_VIDEO_DATA_ABSENT";
      if (candidate && typeof candidate === "object" && !Array.isArray(candidate)) {
        if (initialVideo !== null) return {status: "REJECT", error_code: "E_PAGE_PROOF",
          state: "PAGE_REJECTED", reason: "PAGE_URL_REJECTED"};
        initialVideo = candidate;
        initialStateReason = "METADATA_FIELDS_PENDING";
      }
    } catch {}
  }
  const ownerAnchorIdentities = new Set();
  const ownerProofRoots = document.querySelectorAll(
    "#v_upinfo,.up-info-container,.up-panel-container,.video-owner"
  );
  for (const root of ownerProofRoots) {
    if (root === null || typeof root.querySelectorAll !== "function") continue;
    for (const anchor of root.querySelectorAll("a[href]")) {
      try {
        const href = new URL(anchor.href, location.href);
        if (href.origin !== "https://space.bilibili.com" ||
            !/^\/[1-9][0-9]{0,19}\/?$/.test(href.pathname)) {
          continue;
        }
        const ownerUid = href.pathname.replace(/^\//, "").replace(/\/$/, "");
        ownerAnchorIdentities.add(`https://space.bilibili.com/${ownerUid}`);
      } catch {}
    }
  }
  const canonicalOwnerUrl = `https://space.bilibili.com/${job.creator_uid}`;
  const ownerAnchorExact = ownerAnchorIdentities.size === 1 &&
    ownerAnchorIdentities.has(canonicalOwnerUrl);
  const ownerAnchorReason = ownerAnchorExact ? null :
    (ownerAnchorIdentities.size === 0 ? "OWNER_ANCHOR_ABSENT" :
      (ownerAnchorIdentities.size === 1 ?
        "OWNER_ANCHOR_MISMATCH" : "OWNER_ANCHOR_AMBIGUOUS"));
  let initialMetadata = null;
  if (initialVideo !== null) {
    if (initialVideo.bvid !== job.bvid) return {status: "REJECT", error_code: "E_PAGE_PROOF",
      state: "PAGE_REJECTED", reason: "PAGE_BVID_REJECTED"};
    if (!Array.isArray(initialVideo.pages) || initialVideo.pages.length === 0) {
      return {status: "REJECT", error_code: "E_PAGE_PROOF",
        state: "PAGE_REJECTED", reason: "PAGE_URL_REJECTED"};
    }
    if (initialVideo.pages.length > 1) {
      return {status: "REJECT", error_code: "E_MULTI_PART",
        state: "PAGE_REJECTED", reason: "PAGE_MULTIPART_REJECTED"};
    }
    const initialPage = initialVideo.pages[0];
    const initialDimension = initialVideo.dimension;
    const pageDimension = initialPage?.dimension;
    const positiveSafeInteger = value => typeof value === "number" &&
      Number.isSafeInteger(value) && value > 0;
    const positiveFiniteNumber = value => typeof value === "number" &&
      Number.isFinite(value) && value > 0;
    if (!initialPage || typeof initialPage !== "object" || Array.isArray(initialPage) ||
        !Object.prototype.hasOwnProperty.call(initialPage, "cid") ||
        !Object.prototype.hasOwnProperty.call(initialPage, "page") ||
        !Object.prototype.hasOwnProperty.call(initialPage, "duration") ||
        !Object.prototype.hasOwnProperty.call(initialPage, "dimension") ||
        !initialDimension || typeof initialDimension !== "object" || Array.isArray(initialDimension) ||
        !pageDimension || typeof pageDimension !== "object" || Array.isArray(pageDimension) ||
        !positiveSafeInteger(initialVideo.cid) || !positiveSafeInteger(initialPage.cid) ||
        initialPage.cid !== initialVideo.cid || !positiveSafeInteger(initialPage.page) ||
        initialPage.page !== 1 || !positiveFiniteNumber(initialVideo.duration) ||
        !positiveFiniteNumber(initialPage.duration) || initialPage.duration !== initialVideo.duration ||
        !positiveSafeInteger(initialDimension.width) ||
        !positiveSafeInteger(initialDimension.height) ||
        !positiveSafeInteger(pageDimension.width) ||
        !positiveSafeInteger(pageDimension.height) ||
        pageDimension.width !== initialDimension.width ||
        pageDimension.height !== initialDimension.height) {
      return {status: "REJECT", error_code: "E_PAGE_PROOF",
        state: "PAGE_REJECTED", reason: "PAGE_URL_REJECTED"};
    }
    const initialOwner = String(initialVideo.owner?.mid ?? "");
    if (initialOwner !== "" && initialOwner !== job.creator_uid) {
      return {status: "REJECT", error_code: "E_OWNER",
        state: "PAGE_REJECTED", reason: "PAGE_OWNER_REJECTED"};
    }
    initialMetadata = {
      duration: initialVideo.duration,
      width: initialDimension.width,
      height: initialDimension.height,
      owner: initialOwner
    };
  }
  let metadataSource = "HTML_MEDIA_ELEMENT";
  let durationSeconds = video.duration;
  let videoWidth = video.videoWidth;
  let videoHeight = video.videoHeight;
  let readyState = video.readyState;
  if (initialMetadata?.owner === "" && !ownerAnchorExact) {
    return {status: "PENDING", terminal_error_code: "E_PAGE_OWNER_ANCHOR_UNAVAILABLE",
      state: "OWNER_PENDING", reason: ownerAnchorReason};
  }
  if (!Number.isFinite(durationSeconds) || durationSeconds <= 0 || readyState < 1 ||
      videoWidth <= 0 || videoHeight <= 0) {
    if (initialMetadata !== null &&
        (initialMetadata.owner === job.creator_uid || (initialMetadata.owner === "" && ownerAnchorExact))) {
      metadataSource = "BILIBILI_INITIAL_STATE";
      durationSeconds = initialMetadata.duration;
      videoWidth = initialMetadata.width;
      videoHeight = initialMetadata.height;
      readyState = 1;
    } else if (!Number.isFinite(durationSeconds) || durationSeconds <= 0 || readyState < 1) {
      if (!PAGE_METADATA_UNAVAILABLE_REASONS.has(initialStateReason)) {
        return {status: "REJECT", error_code: "E_PAGE_PROOF",
          state: "PAGE_REJECTED", reason: "PAGE_URL_REJECTED"};
      }
      return {status: "PENDING", terminal_error_code: "E_PAGE_METADATA_NOT_READY",
        state: "METADATA_NOT_READY", reason: initialStateReason};
    } else {
      return {status: "PENDING", terminal_error_code: "E_PAGE_DIMENSIONS_UNAVAILABLE",
        state: "DIMENSIONS_PENDING", reason: "VIDEO_DIMENSIONS_PENDING"};
    }
  }
  if (!ownerAnchorExact && String(initialVideo?.owner?.mid ?? "") !== job.creator_uid) {
    return {status: "PENDING", terminal_error_code: "E_PAGE_OWNER_ANCHOR_UNAVAILABLE",
      state: "OWNER_PENDING", reason: ownerAnchorReason};
  }
  const durationMs = Math.round(durationSeconds * 1000);
  const tolerance = Math.max(1500, Math.min(10000, Math.ceil(job.expected_duration_ms / 1000)));
  if (Math.abs(durationMs - job.expected_duration_ms) > tolerance) {
    return {status: "REJECT", error_code: "E_DURATION",
      state: "PAGE_REJECTED", reason: "PAGE_DURATION_REJECTED"};
  }
  return {
    status: "READY",
    document_focus_diagnostic: documentFocusDiagnostic,
    document_visibility_diagnostic: documentVisibilityDiagnostic,
    proof: {
      job_id: job.job_id,
      bvid: job.bvid,
      creator_uid: job.creator_uid,
      canonical_url: job.canonical_url,
      task_nonce: taskNonce,
      observed_at_unix_ms: Date.now(),
      metadata_source: metadataSource,
      observed_duration_ms: durationMs,
      video_width: videoWidth,
      video_height: videoHeight,
      ready_state: readyState,
      eme_present: video.mediaKeys !== null
    }
  };
}

async function observe(job, binding, deadlineMs = PAGE_PROOF_DEADLINE_MS) {
  const taskNonce = randomHex(16);
  const startedAtUnixMs = Date.now();
  const deadlineUnixMs = startedAtUnixMs + deadlineMs;
  let pendingTerminalCode = "E_PAGE_PROOF";
  let pendingState = "PAGE_REJECTED";
  let pendingReason = "PAGE_IDENTITY_REJECTED";
  let attempts = 0;
  let stableSnapshots = 0;
  let stableSignature = null;
  let stableRejectSnapshots = 0;
  let stableRejectSignature = null;
  const deadlineCode = () => pendingTerminalCode === "E_PAGE_METADATA_NOT_READY" ?
    "E_PAGE_METADATA_UNAVAILABLE" : pendingTerminalCode;
  while (true) {
    await revalidateBoundTab(binding, job.bvid);
    const remainingBeforeInvocationMs = deadlineUnixMs - Date.now();
    if (remainingBeforeInvocationMs <= 0) {
      throw pageReadinessError(
        deadlineCode(), attempts, startedAtUnixMs, pendingState, pendingReason
      );
    }
    const invocationBudgetMs = Math.min(PAGE_PROOF_INVOCATION_TIMEOUT_MS, remainingBeforeInvocationMs);
    let deadlineTimer = null;
    let results;
    attempts += 1;
    try {
      results = await Promise.race([
        chromeApiCall(chrome.scripting, "executeScript", [{
          target: {tabId: binding.tabId, frameIds: [0]}, world: "ISOLATED", func: injectedObservation,
          args: [job, taskNonce]
        }], "E_PAGE_IDENTITY_UNAVAILABLE", "SCRIPTING_EXECUTE_FAILED"),
        new Promise((resolve, reject) => {
          deadlineTimer = setTimeout(() => reject(new Error("E_PAGE_SCRIPT_TIMEOUT")), invocationBudgetMs);
        })
      ]);
    } catch (error) {
      if (error?.message === "E_PAGE_SCRIPT_TIMEOUT") {
        pendingTerminalCode = "E_PAGE_SCRIPT_TIMEOUT";
        pendingState = "SCRIPT_TIMEOUT";
        pendingReason = "SCRIPT_INVOCATION_FAILED";
      } else {
        pendingTerminalCode = "E_PAGE_IDENTITY_UNAVAILABLE";
        pendingState = "IDENTITY_PENDING";
        pendingReason = "PAGE_SCRIPTING_PENDING";
      }
      stableSnapshots = 0;
      stableSignature = null;
      stableRejectSnapshots = 0;
      stableRejectSignature = null;
      continue;
    } finally {
      if (deadlineTimer !== null) clearTimeout(deadlineTimer);
    }
    if (Date.now() >= deadlineUnixMs) {
      throw pageReadinessError(
        deadlineCode(), attempts, startedAtUnixMs, pendingState, pendingReason
      );
    }
    if (!Array.isArray(results) || results.length !== 1 || !isPlainObject(results[0]) ||
        !isPlainObject(results[0].result)) {
      pendingTerminalCode = "E_PAGE_IDENTITY_UNAVAILABLE";
      pendingState = "IDENTITY_PENDING";
      pendingReason = "PAGE_DOM_IDENTITY_PENDING";
      stableSnapshots = 0;
      stableSignature = null;
      stableRejectSnapshots = 0;
      stableRejectSignature = null;
      continue;
    }
    const result = results[0].result;
    if (result.status === "READY" &&
        exactKeys(result, ["document_focus_diagnostic", "document_visibility_diagnostic", "proof", "status"]) &&
        DOCUMENT_FOCUS_DIAGNOSTICS.has(result.document_focus_diagnostic) &&
        DOCUMENT_VISIBILITY_DIAGNOSTICS.has(result.document_visibility_diagnostic) &&
        exactKeys(result.proof, PAGE_PROOF_KEYS)) {
      if (result.document_focus_diagnostic !== "DOCUMENT_FOCUS_TRUE") {
        recordExtensionDiagnostic(result.document_focus_diagnostic);
      }
      if (result.document_visibility_diagnostic !== "DOCUMENT_VISIBILITY_VISIBLE") {
        recordExtensionDiagnostic(result.document_visibility_diagnostic);
      }
      const signature = JSON.stringify(PAGE_PROOF_KEYS.filter(
        key => key !== "observed_at_unix_ms" && key !== "task_nonce"
      ).map(key => result.proof[key]));
      stableSnapshots = signature === stableSignature ? stableSnapshots + 1 : 1;
      stableSignature = signature;
      stableRejectSnapshots = 0;
      stableRejectSignature = null;
      if (stableSnapshots >= PAGE_PROOF_STABLE_SNAPSHOTS) return result.proof;
      pendingTerminalCode = "E_PAGE_STABILITY_TIMEOUT";
      pendingState = "READY_UNSTABLE";
      pendingReason = "STABLE_SNAPSHOTS_PENDING";
    } else if (result.status === "REJECT" &&
        exactKeys(result, ["error_code", "reason", "state", "status"]) &&
        PREPARELESS_REJECT_CODES.has(result.error_code) &&
        isCanonicalPreparelessTerminal(result.error_code, {
          attempts, elapsed_ms: Math.max(0, Math.min(7200000, Date.now() - startedAtUnixMs)),
          state: result.state, reason: result.reason
        })) {
      const stableIdentityReject = new Set([
        "E_OWNER", "E_PAGE_ACCESS_CONTROL", "E_PAGE_PROOF"
      ]).has(result.error_code);
      if (!stableIdentityReject) {
        throw pageReadinessError(
          result.error_code, attempts, startedAtUnixMs, result.state, result.reason
        );
      }
      pendingTerminalCode = result.error_code;
      pendingState = result.state;
      pendingReason = result.reason;
      stableSnapshots = 0;
      stableSignature = null;
      const rejectSignature = `${result.error_code}\0${result.state}\0${result.reason}`;
      stableRejectSnapshots = rejectSignature === stableRejectSignature ?
        stableRejectSnapshots + 1 : 1;
      stableRejectSignature = rejectSignature;
      if (stableRejectSnapshots >= PAGE_PROOF_STABLE_SNAPSHOTS) {
        throw pageReadinessError(
          result.error_code, attempts, startedAtUnixMs, result.state, result.reason
        );
      }
    } else if (result.status !== "PENDING" ||
        !exactKeys(result, ["reason", "state", "status", "terminal_error_code"]) ||
        !PAGE_PENDING_TERMINAL_CONTRACT.has(result.terminal_error_code)) {
      throw new Error("E_PAGE_PROOF");
    } else {
      const [expectedState, allowedReasons] = PAGE_PENDING_TERMINAL_CONTRACT.get(result.terminal_error_code);
      if (!PAGE_PENDING_STATES.has(result.state) || result.state !== expectedState ||
          !PAGE_DIAGNOSTIC_REASONS.has(result.reason) || !allowedReasons.has(result.reason)) {
        throw new Error("E_PAGE_PROOF");
      }
      pendingTerminalCode = result.terminal_error_code;
      pendingState = result.state;
      pendingReason = result.reason;
      stableSnapshots = 0;
      stableSignature = null;
      stableRejectSnapshots = 0;
      stableRejectSignature = null;
    }
    const remainingMs = deadlineUnixMs - Date.now();
    if (remainingMs <= 0) {
      throw pageReadinessError(
        deadlineCode(), attempts, startedAtUnixMs, pendingState, pendingReason
      );
    }
    await new Promise(resolve => setTimeout(resolve, Math.min(PAGE_PROOF_POLL_MS, remainingMs)));
  }
}

function normalizeCookie(cookie, storeId) {
  return {
    name: cookie.name,
    value: cookie.value,
    domain: cookie.domain,
    host_only: cookie.hostOnly,
    path: cookie.path,
    secure: cookie.secure,
    http_only: cookie.httpOnly,
    same_site: cookie.sameSite,
    session: cookie.session,
    expiration_unix: cookie.session === true ? null : Math.floor(cookie.expirationDate),
    store_id: cookie.storeId,
    partition_key: cookie.partitionKey === undefined ? null : cookie.partitionKey
  };
}

function cookiePathMatches(path, bvid) {
  const wanted = `/video/${bvid}`;
  return path === "/" || (wanted.startsWith(path) &&
    (path.endsWith("/") || path.length === wanted.length || wanted[path.length] === "/"));
}

function safeCookieString(value, minimum, maximumUtf8) {
  if (typeof value !== "string" || COOKIE_CONTROL_RE.test(value)) return false;
  const bytes = new TextEncoder().encode(value).length;
  return bytes >= minimum && bytes <= maximumUtf8;
}

function validBrowserCookie(cookie, storeId, proof, bvid, partitioned) {
  return exactKeys(cookie, COOKIE_KEYS) &&
    safeCookieString(cookie.name, 1, 256) && safeCookieString(cookie.value, 1, 4096) &&
    typeof cookie.host_only === "boolean" &&
    cookie.domain === (cookie.host_only ? "www.bilibili.com" : ".bilibili.com") &&
    safeCookieString(cookie.path, 1, 1024) &&
    cookie.path.startsWith("/") && cookiePathMatches(cookie.path, bvid) &&
    typeof cookie.secure === "boolean" && typeof cookie.http_only === "boolean" &&
    typeof cookie.session === "boolean" && COOKIE_SAME_SITE.has(cookie.same_site) &&
    STORE_ID_RE.test(cookie.store_id) && cookie.store_id === storeId &&
    (partitioned ? validPartitionKeyDescriptor(cookie.partition_key) : cookie.partition_key === null) &&
    (cookie.session
      ? cookie.expiration_unix === null
      : Number.isSafeInteger(cookie.expiration_unix) && cookie.expiration_unix >= 1 &&
        cookie.expiration_unix > Math.floor(proof.observed_at_unix_ms / 1000));
}

function validCookie(cookie, storeId, proof, bvid) {
  return validBrowserCookie(cookie, storeId, proof, bvid, false);
}

function validCookieSet(cookies, storeId, proof, bvid) {
  return Array.isArray(cookies) && cookies.length >= 1 && cookies.length <= MAX_COOKIE_COUNT &&
    cookies.every(cookie => validCookie(cookie, storeId, proof, bvid));
}

function validPartitionKeyDescriptor(value) {
  if (value === null || typeof value !== "object" || Array.isArray(value)) return false;
  const keys = Object.keys(value).sort().join("\0");
  if (!["", "hasCrossSiteAncestor", "topLevelSite", "hasCrossSiteAncestor\0topLevelSite"].includes(keys)) {
    return false;
  }
  if (Object.prototype.hasOwnProperty.call(value, "hasCrossSiteAncestor") &&
      typeof value.hasCrossSiteAncestor !== "boolean") return false;
  if (!Object.prototype.hasOwnProperty.call(value, "topLevelSite")) return true;
  if (!safeCookieString(value.topLevelSite, 1, 2048)) return false;
  try {
    const site = new URL(value.topLevelSite);
    return (site.protocol === "https:" || site.protocol === "http:") &&
      site.origin === value.topLevelSite && site.username === "" && site.password === "" &&
      site.pathname === "/" && site.search === "" && site.hash === "";
  } catch {
    return false;
  }
}

function validRawSessionExpiration(cookie, proof) {
  if (typeof cookie.session !== "boolean") return false;
  if (cookie.session) return cookie.expirationDate === undefined;
  if (typeof cookie.expirationDate !== "number" || !Number.isFinite(cookie.expirationDate)) return false;
  const expirationUnix = Math.floor(cookie.expirationDate);
  return Number.isSafeInteger(expirationUnix) && expirationUnix >= 1 &&
    expirationUnix > Math.floor(proof.observed_at_unix_ms / 1000);
}

function selectedCookieRelevance(cookie, storeId, bvid, proof) {
  if (cookie === null || typeof cookie !== "object" || Array.isArray(cookie) ||
      !safeCookieString(cookie.name, 1, 256)) return "AMBIGUOUS";
  if (!TRANSFER_COOKIE_NAMES.has(cookie.name)) return "IRRELEVANT_NAME";
  if (cookie.partitionKey !== undefined) {
    if (!validRawSessionExpiration(cookie, proof)) return "AMBIGUOUS";
    let normalized = null;
    try {
      normalized = normalizeCookie(cookie, storeId);
      return validBrowserCookie(normalized, storeId, proof, bvid, true)
        ? "IRRELEVANT_PARTITIONED" : "AMBIGUOUS";
    } catch {
      return "AMBIGUOUS";
    } finally {
      if (normalized !== null) {
        normalized.name = "";
        normalized.value = "";
      }
    }
  }
  return "SELECTED";
}

function selectTransferCookies(rawCookies, storeId, proof, bvid) {
  const selected = [];
  const requiredNames = new Set();
  if (!Array.isArray(rawCookies)) return {ok: false, reason: "COOKIE_API_SHAPE", cookies: selected};
  if (rawCookies.length > MAX_COOKIE_COUNT) {
    return {ok: false, reason: "COOKIE_TRANSFER_OVERFLOW", cookies: selected};
  }
  for (const rawCookie of rawCookies) {
    const relevance = selectedCookieRelevance(rawCookie, storeId, bvid, proof);
    if (relevance === "IRRELEVANT_NAME" || relevance === "IRRELEVANT_PARTITIONED") continue;
    if (relevance !== "SELECTED") {
      return {ok: false, reason: "COOKIE_RELEVANCE_AMBIGUOUS", cookies: selected};
    }
    const cookie = normalizeCookie(rawCookie, storeId);
    selected.push(cookie);
    if (!validCookie(cookie, storeId, proof, bvid)) {
      return {ok: false, reason: "COOKIE_SELECTED_INVALID", cookies: selected};
    }
    if (REQUIRED_AUTH_COOKIE_NAMES.has(cookie.name)) requiredNames.add(cookie.name);
  }
  if (selected.length === 0) return {ok: false, reason: "COOKIE_AUTH_SET_EMPTY", cookies: selected};
  for (const requiredName of REQUIRED_AUTH_COOKIE_NAMES) {
    if (!requiredNames.has(requiredName)) {
      return {ok: false, reason: "COOKIE_AUTH_SET_EMPTY", cookies: selected};
    }
  }
  const pathSpecificity = cookie => new TextEncoder().encode(cookie.path).length;
  const bestSpecificity = Math.max(...selected.map(pathSpecificity));
  const highestPrecedence = selected.filter(cookie => pathSpecificity(cookie) === bestSpecificity);
  const firstValue = highestPrecedence[0].value;
  if (highestPrecedence.some(cookie => cookie.value !== firstValue)) {
    return {ok: false, reason: "COOKIE_EQUAL_PRECEDENCE_CONFLICT", cookies: selected};
  }
  highestPrecedence.sort((left, right) =>
    Number(right.host_only) - Number(left.host_only) ||
    left.domain.localeCompare(right.domain) || left.path.localeCompare(right.path) ||
    left.same_site.localeCompare(right.same_site) || Number(right.secure) - Number(left.secure) ||
    Number(right.http_only) - Number(left.http_only) || Number(right.session) - Number(left.session)
  );
  const chosen = highestPrecedence[0];
  for (const cookie of selected) {
    if (cookie !== chosen) {
      cookie.name = "";
      cookie.value = "";
    }
  }
  const transfer = [chosen];
  selected.length = 0;
  const valid = validCookieSet(transfer, storeId, proof, bvid);
  return {ok: valid, reason: valid ? "COOKIE_TRANSFER_READY" : "COOKIE_TRANSFER_INVALID", cookies: transfer};
}

function zeroizeCookies(rawCookies, cookies) {
  for (const cookie of Array.isArray(cookies) ? cookies : []) {
    cookie.name = "";
    cookie.value = "";
  }
  for (const cookie of Array.isArray(rawCookies) ? rawCookies : []) {
    if (cookie !== null && typeof cookie === "object") {
      try { cookie.name = ""; } catch {}
      try { cookie.value = ""; } catch {}
    }
  }
  if (Array.isArray(cookies)) cookies.length = 0;
  if (Array.isArray(rawCookies)) rawCookies.length = 0;
}

async function abortPreparedForCookieAccess(session, job, leaseId, prepareId, rawCookies, cookies, reason) {
  lastCookieAccessReason = COOKIE_ACCESS_REASONS.has(reason) ? reason : "COOKIE_SELECTION_EXCEPTION";
  zeroizeCookies(rawCookies, cookies);
  const aborted = await session.send({
    schema: SCHEMA, type: "abort_prepare", job_id: job.job_id, lease_id: leaseId,
    prepare_id: prepareId, error_code: "E_COOKIE_ACCESS", error_reason: lastCookieAccessReason
  });
  if (!(await validateResponse(aborted, "abort_prepare")) || aborted.phase !== "FAILED" ||
      aborted.error_code !== "E_COOKIE_ACCESS" || aborted.prepare_id !== prepareId ||
      aborted.job?.job_id !== job.job_id || aborted.lease_id !== leaseId) {
    throw new Error("E_PREPARE");
  }
  return aborted;
}

async function runJobCore(session, job, leaseId, lifecycle) {
  lastTabDriftReason = null;
  lastCookieAccessReason = null;
  lastPageReadinessDiagnostic = null;
  let selectedTab;
  let proof;
  const flowStartedAtUnixMs = Date.now();
  const foregroundFlow = {
    startedAtUnixMs: flowStartedAtUnixMs,
    deadlineUnixMs: flowStartedAtUnixMs + PAGE_PROOF_DEADLINE_MS,
    foregroundUsed: false
  };
  try {
    selectedTab = await targetTab(session, job, leaseId, foregroundFlow);
    lifecycle.binding = selectedTab.binding;
    proof = await acquirePageProof(session, job, leaseId, selectedTab, foregroundFlow);
    await revalidateBoundTab(selectedTab.binding, job.bvid);
  } catch (error) {
    const code = typeof error?.message === "string" && PREPARELESS_REJECT_CODES.has(error.message)
      ? error.message : null;
    if (code === null) throw error;
    const candidate = isPageReadinessDiagnostic(error?.page_readiness_diagnostic)
      ? error.page_readiness_diagnostic
      : isPageReadinessDiagnostic(lastPageReadinessDiagnostic)
      ? lastPageReadinessDiagnostic
      : fallbackPageReadinessDiagnostic(code);
    const diagnostic = isCanonicalPreparelessTerminal(code, candidate)
      ? candidate : fallbackPageReadinessDiagnostic(code);
    if (!isCanonicalPreparelessTerminal(code, diagnostic)) throw new Error("E_REJECT");
    const rejected = await session.send({
      schema: SCHEMA, type: "reject", job_id: job.job_id, lease_id: leaseId,
      error_code: code, diagnostic
    });
    if (!(await validateResponse(rejected, "reject")) || rejected.phase !== "FAILED" ||
        rejected.error_code !== code || rejected.job?.job_id !== job.job_id || rejected.lease_id !== leaseId) {
      throw new Error("E_REJECT");
    }
    return rejected;
  }
  const prepareId = randomHex(16);
  const prepared = await session.send({
    schema: SCHEMA, type: "prepare", extension_build: EXTENSION_BUILD,
    lease_id: leaseId, prepare_id: prepareId, job, page_proof: proof
  }, 150000);
  const preparedValid = await validateResponse(prepared, "prepare");
  if (preparedValid && prepared.phase === "COMPLETE" && prepared.prepare_id === prepareId &&
      prepared.job?.job_id === job.job_id && prepared.lease_id === leaseId &&
      prepared.progress === 100 && prepared.error_code === null &&
      prepared.formal_filename === `${job.bvid}.mkv` &&
      prepared.mapping_filename === `${job.bvid}.download.json`) {
    return prepared;
  }
  if (!preparedValid || prepared.phase !== "READY" || prepared.prepare_id !== prepareId) {
    const code = preparedValid && prepared.phase === "FAILED" && ERROR_CODE_RE.test(prepared.error_code || "")
      ? prepared.error_code : "E_PREPARE";
    throw new Error(code);
  }
  const storeId = selectedTab.binding.cookieStoreId;
  let rawCookies = [];
  let cookies = [];
  try {
    rawCookies = await chrome.cookies.getAll({
      url: canonicalUrl(job.bvid),
      name: AUTH_COOKIE_NAME,
      storeId
    });
  } catch {
    return abortPreparedForCookieAccess(session, job, leaseId, prepareId, rawCookies, cookies, "COOKIE_API_ERROR");
  }
  let selection;
  try {
    selection = selectTransferCookies(rawCookies, storeId, proof, job.bvid);
  } catch {
    return abortPreparedForCookieAccess(
      session, job, leaseId, prepareId, rawCookies, cookies, "COOKIE_SELECTION_EXCEPTION"
    );
  }
  cookies = selection.cookies;
  if (!selection.ok) {
    return abortPreparedForCookieAccess(
      session, job, leaseId, prepareId, rawCookies, cookies, selection.reason
    );
  }
  let started;
  try {
    started = await session.send({
      schema: SCHEMA, type: "start", extension_build: EXTENSION_BUILD,
      lease_id: leaseId, prepare_id: prepareId, job, cookie_store_id: storeId,
      page_proof: proof, cookies
    }, 30000);
  } finally {
    zeroizeCookies(rawCookies, cookies);
  }
  if (!(await validateResponse(started, "status")) || started.job?.job_id !== job.job_id) {
    throw new Error("E_START");
  }
  let state = started;
  while (!["COMPLETE", "FAILED", "POSTPROCESS_FAILED", "CANCELED"].includes(state.phase)) {
    await new Promise(resolve => setTimeout(resolve, 1000));
    state = await session.send({schema: SCHEMA, type: "status", job_id: job.job_id, lease_id: leaseId});
    if (!(await validateResponse(state, "status")) || state.job?.job_id !== job.job_id) throw new Error("E_STATUS");
  }
  return state;
}

async function runJob(session, job, leaseId) {
  const lifecycle = {binding: null};
  try {
    return await runJobCore(session, job, leaseId, lifecycle);
  } finally {
    // The durable session record is the authority. This also closes a tab when
    // a restart/rebind path lost its in-memory binding after Host start.
    await cleanupOwnedTab();
  }
}

async function drainQueue() {
  if (drainLease) return;
  drainLease = true;
  lastDrainErrorCode = null;
  let session;
  try {
    session = nativeSession();
    const hello = await session.send({schema: SCHEMA, type: "hello", extension_build: EXTENSION_BUILD});
    const helloValid = await validateResponse(hello, "hello");
    if (!helloValid) throw new Error("E_HELLO");
    if (hello.phase === "FAILED") throw new Error(hello.error_code || "E_HOST");
    if (hello.maintenance.reload_required) {
      const token = hello.maintenance.reload_token;
      if (!HEX32_RE.test(token || "")) return;
      const response = await session.send({schema: SCHEMA, type: "reload_begin", extension_build: EXTENSION_BUILD, reload_token: token});
      if (!(await validateResponse(response, "reload_begin")) || response.phase !== "RELOAD_REQUIRED") return;
      session.disconnect();
      session = null;
      chrome.runtime.reload();
      return;
    }
    const polled = await session.send({schema: SCHEMA, type: "poll"});
    const pollValid = await validateResponse(polled, "poll");
    if (!pollValid) throw new Error("E_POLL");
    const owned = await loadOwnedTabRecord();
    const continuesOwnedJob = polled.phase === "READY" && polled.job && polled.lease_id &&
      owned !== null && owned.job_id === polled.job.job_id && owned.lease_id === polled.lease_id;
    if (owned !== null && !continuesOwnedJob) await cleanupOwnedTab(owned);
    if (["FAILED", "POSTPROCESS_FAILED"].includes(polled.phase)) {
      throw new Error(polled.error_code || "E_HOST");
    }
    if (polled.phase === "COMPLETE") {
      if (!polled.job || !polled.lease_id || polled.progress !== 100 || polled.error_code !== null ||
          polled.formal_filename !== `${polled.job.bvid}.mkv` ||
          polled.mapping_filename !== `${polled.job.bvid}.download.json`) {
        throw new Error("E_POLL");
      }
      return;
    }
    if (polled.phase !== "READY" || !polled.job || !polled.lease_id) return;
    await runJob(session, polled.job, polled.lease_id);
  } catch (error) {
    // Memory-only safe code: never persist secrets, URLs, protocol payloads, or Host diagnostics here.
    lastDrainErrorCode = safeErrorCode(error);
  } finally {
    if (session) session.disconnect();
    drainLease = false;
  }
}

function schedule() {
  chrome.alarms.create("bili-auth-queue", {periodInMinutes: 1});
  void drainQueue();
}

chrome.runtime.onInstalled.addListener(schedule);
chrome.runtime.onStartup.addListener(schedule);
chrome.alarms.onAlarm.addListener(alarm => {
  if (alarm?.name === "bili-auth-queue") void drainQueue();
});