#!/usr/bin/env node

// Guards gateway -> mobile-client event coverage drift.
//
// Source of truth for server->client event names is GATEWAY_EVENTS in
// src/gateway/server-methods-list.ts (the catalog advertised to clients in
// hello-ok `features.events`). packages/gateway-protocol only types the event
// frame envelope (`event: NonEmptyString`), so the gateway catalog is the most
// canonical single list of wire event names.
//
// Client "handled" sets are extracted with deliberately simple parsing over
// the mobile app sources: Swift `switch <x>.event { case "..." }` blocks plus
// `.event == "..."` comparisons, and Kotlin `when (event) { "..." -> }` blocks
// plus `event == "..."` comparisons scoped to `fun handle*Event(...)` bodies.
// Swift case labels may use qualified static string constants; those are
// resolved across the scanned source tree so deleting the real handler cannot
// hide behind an allowlist entry. Events a client intentionally does not
// consume live in scripts/protocol-event-coverage.allowlist.json.
import fs from "node:fs";
import path from "node:path";
import { fileURLToPath } from "node:url";

const GATEWAY_EVENTS_FILE = "src/gateway/server-methods-list.ts";
const GATEWAY_EVENT_CONSTANTS_FILE = "src/gateway/events.ts";
const ALLOWLIST_FILE = "scripts/protocol-event-coverage.allowlist.json";

// Scan roots per client. The sentinel files are the primary event dispatch
// surfaces; if one moves, the check must fail loudly instead of silently
// passing with an empty handled set.
const IOS_SCAN_ROOTS = ["apps/ios/Sources", "apps/shared/OpenClawKit/Sources"];
const IOS_SENTINEL_FILE = "apps/ios/Sources/Chat/IOSGatewayChatTransport.swift";
const ANDROID_SCAN_ROOT = "apps/android/app/src/main/java/ai/openclaw/app";
const ANDROID_SENTINEL_FILES = [
  "apps/android/app/src/main/java/ai/openclaw/app/gateway/GatewaySession.kt",
  "apps/android/app/src/main/java/ai/openclaw/app/chat/ChatController.kt",
];

// Minimum plausible catalog size; a partial parse below this means the
// GATEWAY_EVENTS array changed shape and the extractor needs updating.
const MIN_EXPECTED_GATEWAY_EVENTS = 10;

const GATEWAY_EVENTS_BLOCK_RE = /export const GATEWAY_EVENTS = \[([\s\S]*?)\];/u;
const SWIFT_EVENT_SWITCH_RE = /\bswitch\s+\w+(?:\.\w+)*\.event\s*\{/u;
const SWIFT_CASE_LABEL_RE = /^\s*case\s+(.+?):/u;
const SWIFT_TYPE_DECLARATION_RE =
  /^\s*(?:(?:private|fileprivate|internal|public)\s+)?(?:enum|struct|class|actor|extension)\s+([A-Za-z_]\w*)[^{]*\x7b/u;
const SWIFT_STATIC_STRING_CONSTANT_RE = /^\s*static\s+let\s+([A-Za-z_]\w*)\s*=\s*"([^"]+)"/u;
const SWIFT_QUALIFIED_CONSTANT_RE = /\b([A-Za-z_]\w*\.[A-Za-z_]\w*)\b/gu;
const KOTLIN_EVENT_WHEN_RE = /\bwhen\s*\(\s*event\s*\)\s*\{/u;
// Kotlin gateway handlers follow the `handle*Event` naming convention
// (handleEvent, handleGatewayEvent, handleExecApprovalGatewayEvent, ...).
// Handlers named differently surface as loud "unhandled" failures, which is
// the safe direction for a coverage gate.
const KOTLIN_HANDLER_FUN_RE = /\bfun\s+handle\w*Event\s*\(/u;
const KOTLIN_CASE_LABEL_RE = /^\s*((?:"[^"]+"\s*,\s*)*"[^"]+")\s*->/u;
const SWIFT_EVENT_COMPARISON_RE = /\.event\s*==\s*"([^"]+)"/gu;
const KOTLIN_EVENT_COMPARISON_RE = /\bevent\s*==\s*"([^"]+)"/gu;
const STRING_LITERAL_RE = /"([^"]+)"/gu;

function isMainModule() {
  return process.argv[1] ? path.resolve(process.argv[1]) === fileURLToPath(import.meta.url) : false;
}

/**
 * Extracts the gateway event name list from server-methods-list.ts source.
 * Bare identifiers in the array (e.g. GATEWAY_EVENT_UPDATE_AVAILABLE) are
 * resolved against constantsSource (src/gateway/events.ts).
 */
export function extractGatewayEventNames(listSource, constantsSource) {
  const block = GATEWAY_EVENTS_BLOCK_RE.exec(listSource);
  if (!block) {
    throw new Error(
      `Could not find the GATEWAY_EVENTS array in ${GATEWAY_EVENTS_FILE}. ` +
        "If the catalog moved, update scripts/check-protocol-event-coverage.mjs.",
    );
  }
  const body = block[1].replace(/\/\*[\s\S]*?\*\//gu, "").replace(/\/\/[^\n]*/gu, "");
  const names = [];
  for (const token of body.matchAll(/"([^"]+)"|([A-Za-z_$][\w$]*)/gu)) {
    if (token[1]) {
      names.push(token[1]);
      continue;
    }
    const identifier = token[2];
    const constant = new RegExp(`export const ${identifier} = "([^"]+)"`, "u").exec(
      constantsSource,
    );
    if (!constant) {
      throw new Error(
        `Could not resolve GATEWAY_EVENTS identifier "${identifier}" from ${GATEWAY_EVENT_CONSTANTS_FILE}.`,
      );
    }
    names.push(constant[1]);
  }
  if (names.length < MIN_EXPECTED_GATEWAY_EVENTS) {
    throw new Error(
      `Extracted only ${names.length} gateway events from ${GATEWAY_EVENTS_FILE}; ` +
        "the array shape likely changed. Update the extractor.",
    );
  }
  return names;
}

// Neutralizes string literals and line comments so brace counting cannot be
// confused by braces inside strings or comments.
function sanitizeLineForBraces(line) {
  return line
    .replace(/\\"/gu, "")
    .replace(/"[^"]*"/gu, '""')
    .replace(/\/\/.*$/u, "");
}

// Collects case-label lines at depth 1 of blocks whose header matches
// headerRe, feeding each into extractLabels. Line-based on purpose: this is a
// drift check, not a parser; sources keep one case label per line.
function collectBlockCaseLabels(source, headerRe, extractLabels) {
  const names = [];
  const lines = source.split("\n");
  for (let i = 0; i < lines.length; i += 1) {
    if (!headerRe.test(lines[i])) {
      continue;
    }
    let depth = 0;
    for (let j = i; j < lines.length; j += 1) {
      const line = lines[j];
      if (depth === 1) {
        extractLabels(line, names);
      }
      const braceSource =
        j === i
          ? sanitizeLineForBraces(line.slice(line.indexOf("{")))
          : sanitizeLineForBraces(line);
      for (const char of braceSource) {
        if (char === "{") {
          depth += 1;
        } else if (char === "}") {
          depth -= 1;
        }
      }
      if (j > i && depth <= 0) {
        break;
      }
    }
  }
  return names;
}

function pushStringLiterals(segment, names) {
  for (const literal of segment.matchAll(STRING_LITERAL_RE)) {
    names.push(literal[1]);
  }
}

/**
 * Extracts qualified static string constants declared at Swift type scope.
 * Type qualification avoids resolving unrelated constants that share a short
 * member name elsewhere in the app.
 */
export function extractSwiftStaticStringConstants(source) {
  const constants = new Map();
  const lines = source.split("\n");
  for (let i = 0; i < lines.length; i += 1) {
    const declaration = SWIFT_TYPE_DECLARATION_RE.exec(lines[i]);
    if (!declaration) {
      continue;
    }
    const typeName = declaration[1];
    let depth = 0;
    for (let j = i; j < lines.length; j += 1) {
      const line = lines[j];
      if (depth === 1) {
        const constant = SWIFT_STATIC_STRING_CONSTANT_RE.exec(line);
        if (constant) {
          constants.set(`${typeName}.${constant[1]}`, constant[2]);
        }
      }
      const braceSource = sanitizeLineForBraces(line);
      for (const char of braceSource) {
        if (char === "{") {
          depth += 1;
        } else if (char === "}") {
          depth -= 1;
        }
      }
      if (j > i && depth <= 0) {
        break;
      }
    }
  }
  return constants;
}

/** Extracts Swift gateway-event case labels, including qualified constants. */
export function extractSwiftHandledEvents(source, constants = new Map()) {
  const names = collectBlockCaseLabels(source, SWIFT_EVENT_SWITCH_RE, (line, sink) => {
    const label = SWIFT_CASE_LABEL_RE.exec(line);
    if (label) {
      pushStringLiterals(label[1], sink);
      const constantReferences = sanitizeLineForBraces(label[1]);
      for (const reference of constantReferences.matchAll(SWIFT_QUALIFIED_CONSTANT_RE)) {
        const value = constants.get(reference[1]);
        if (value) {
          sink.push(value);
        }
      }
    }
  });
  for (const comparison of source.matchAll(SWIFT_EVENT_COMPARISON_RE)) {
    names.push(comparison[1]);
  }
  return new Set(names);
}

// Collects the bodies of Kotlin gateway event handler functions
// (`fun handle*Event(...)`). Signatures may span multiple lines, so scan
// forward from the declaration to the first `{` before brace counting.
function extractKotlinHandlerBodies(source) {
  const bodies = [];
  const lines = source.split("\n");
  for (let i = 0; i < lines.length; i += 1) {
    if (!KOTLIN_HANDLER_FUN_RE.test(lines[i])) {
      continue;
    }
    let depth = 0;
    let opened = false;
    const body = [];
    for (let j = i; j < lines.length; j += 1) {
      const sanitized = sanitizeLineForBraces(lines[j]);
      if (opened) {
        body.push(lines[j]);
      }
      for (const char of sanitized) {
        if (char === "{") {
          depth += 1;
          opened = true;
        } else if (char === "}") {
          depth -= 1;
        }
      }
      if (opened && depth <= 0) {
        break;
      }
    }
    if (opened) {
      bodies.push(body.join("\n"));
    }
  }
  return bodies;
}

/**
 * Extracts event names a Kotlin source handles: string-literal case labels of
 * `when (event)` blocks plus `event == "..."` comparisons, both scoped to
 * `fun handle*Event(...)` bodies. Scoping matters: bare `event == "..."`
 * literals also appear in predicate helpers that are not called from the
 * dispatch path (e.g. gatewayEventInvalidatesNodesDevices in NodeRuntime.kt),
 * and counting those would silently mark events as covered. Swift extraction
 * stays tree-wide because Swift consumption always reads `.event` off a
 * received EventFrame, which does not have that false-positive shape.
 */
export function extractKotlinHandledEvents(source) {
  const names = [];
  for (const body of extractKotlinHandlerBodies(source)) {
    names.push(
      ...collectBlockCaseLabels(body, KOTLIN_EVENT_WHEN_RE, (line, sink) => {
        const label = KOTLIN_CASE_LABEL_RE.exec(line);
        if (label) {
          pushStringLiterals(label[1], sink);
        }
      }),
    );
    for (const comparison of body.matchAll(KOTLIN_EVENT_COMPARISON_RE)) {
      names.push(comparison[1]);
    }
  }
  return new Set(names);
}

/**
 * Compares a client's handled events against the gateway catalog and its
 * allowlist. Returns human-readable error strings. Client-only names (e.g. the
 * client-synthesized "seqGap" pseudo-event) are intentionally ignored; this
 * check only guards the server->client direction.
 */
export function compareEventCoverage(params) {
  const { client, serverEvents, handledEvents, allowlist } = params;
  const errors = [];
  const serverSet = new Set(serverEvents);
  for (const event of serverEvents) {
    if (handledEvents.has(event) || event in allowlist) {
      continue;
    }
    errors.push(
      `[${client}] gateway event "${event}" has no handler and no allowlist entry. ` +
        `Handle it in the ${client} app or add it to ${ALLOWLIST_FILE} with a reason.`,
    );
  }
  for (const [event, reason] of Object.entries(allowlist)) {
    if (typeof reason !== "string" || reason.trim() === "") {
      errors.push(`[${client}] allowlist entry "${event}" needs a non-empty reason string.`);
    }
    if (!serverSet.has(event)) {
      errors.push(
        `[${client}] allowlist entry "${event}" is not a gateway event anymore; remove it from ${ALLOWLIST_FILE}.`,
      );
    } else if (handledEvents.has(event)) {
      errors.push(
        `[${client}] allowlist entry "${event}" is now handled; remove it from ${ALLOWLIST_FILE}.`,
      );
    }
  }
  return errors;
}

function listFilesRecursive(rootDir, extension, fsImpl) {
  const files = [];
  const queue = [rootDir];
  while (queue.length > 0) {
    const current = queue.pop();
    let entries;
    try {
      entries = fsImpl.readdirSync(current, { withFileTypes: true });
    } catch {
      continue;
    }
    for (const entry of entries) {
      const fullPath = path.join(current, entry.name);
      if (entry.isDirectory()) {
        // Test sources match the same event literals but are not product
        // handlers; including them would mask real coverage gaps.
        if (entry.name === "Tests" || entry.name === ".build" || entry.name === "build") {
          continue;
        }
        queue.push(fullPath);
        continue;
      }
      if (entry.isFile() && entry.name.endsWith(extension)) {
        files.push(fullPath);
      }
    }
  }
  return files.toSorted((left, right) => left.localeCompare(right));
}

function readRequiredFile(rootDir, relativePath, fsImpl) {
  const fullPath = path.resolve(rootDir, relativePath);
  try {
    return fsImpl.readFileSync(fullPath, "utf8");
  } catch {
    throw new Error(
      `Required file ${relativePath} is missing. If it moved, update scripts/check-protocol-event-coverage.mjs.`,
    );
  }
}

function loadAllowlist(rootDir, fsImpl) {
  const raw = readRequiredFile(rootDir, ALLOWLIST_FILE, fsImpl);
  let parsed;
  try {
    parsed = JSON.parse(raw);
  } catch (error) {
    throw new Error(`${ALLOWLIST_FILE} is not valid JSON: ${String(error)}`, { cause: error });
  }
  for (const client of ["ios", "android"]) {
    if (typeof parsed[client] !== "object" || parsed[client] === null) {
      throw new Error(`${ALLOWLIST_FILE} must contain an object entry for "${client}".`);
    }
  }
  return parsed;
}

function collectClientHandledEvents(params) {
  const { rootDir, roots, extension, extract, buildExtractContext, sentinels, fsImpl } = params;
  const handled = new Set();
  const sources = new Map();
  for (const root of roots) {
    const rootPath = path.resolve(rootDir, root);
    if (!fsImpl.existsSync(rootPath)) {
      throw new Error(
        `Scan root ${root} is missing. If it moved, update scripts/check-protocol-event-coverage.mjs.`,
      );
    }
    for (const filePath of listFilesRecursive(rootPath, extension, fsImpl)) {
      sources.set(filePath, fsImpl.readFileSync(filePath, "utf8"));
    }
  }
  const extractContext = buildExtractContext?.(sources.values());
  for (const source of sources.values()) {
    for (const event of extract(source, extractContext)) {
      handled.add(event);
    }
  }
  for (const sentinel of sentinels) {
    const source = readRequiredFile(rootDir, sentinel, fsImpl);
    if (extract(source, extractContext).size === 0) {
      throw new Error(
        `Sentinel dispatch file ${sentinel} no longer matches any event names; ` +
          "its event handling likely moved or changed shape. Update scripts/check-protocol-event-coverage.mjs.",
      );
    }
  }
  return handled;
}

function collectSwiftStaticStringConstants(sources) {
  const constants = new Map();
  for (const source of sources) {
    for (const [name, value] of extractSwiftStaticStringConstants(source)) {
      const existing = constants.get(name);
      if (existing !== undefined && existing !== value) {
        throw new Error(`Conflicting Swift string constant values for ${name}.`);
      }
      constants.set(name, value);
    }
  }
  return constants;
}

/**
 * Runs the full coverage check against a repo checkout and returns error
 * strings plus a summary for logging.
 */
export function collectProtocolEventCoverageErrors(params = {}) {
  const rootDir = params.rootDir ?? process.cwd();
  const fsImpl = params.fs ?? fs;

  const serverEvents = extractGatewayEventNames(
    readRequiredFile(rootDir, GATEWAY_EVENTS_FILE, fsImpl),
    readRequiredFile(rootDir, GATEWAY_EVENT_CONSTANTS_FILE, fsImpl),
  );
  const allowlist = loadAllowlist(rootDir, fsImpl);
  const clients = [
    {
      client: "ios",
      handledEvents: collectClientHandledEvents({
        rootDir,
        roots: IOS_SCAN_ROOTS,
        extension: ".swift",
        extract: extractSwiftHandledEvents,
        buildExtractContext: collectSwiftStaticStringConstants,
        sentinels: [IOS_SENTINEL_FILE],
        fsImpl,
      }),
    },
    {
      client: "android",
      handledEvents: collectClientHandledEvents({
        rootDir,
        roots: [ANDROID_SCAN_ROOT],
        extension: ".kt",
        extract: extractKotlinHandledEvents,
        sentinels: ANDROID_SENTINEL_FILES,
        fsImpl,
      }),
    },
  ];

  const errors = [];
  const summaryParts = [];
  for (const { client, handledEvents } of clients) {
    errors.push(
      ...compareEventCoverage({
        client,
        serverEvents,
        handledEvents,
        allowlist: allowlist[client],
      }),
    );
    const handledCount = serverEvents.filter((event) => handledEvents.has(event)).length;
    summaryParts.push(
      `${client} handles ${handledCount}, allowlists ${Object.keys(allowlist[client]).length}`,
    );
  }
  return {
    errors,
    summary: `${serverEvents.length} gateway events; ${summaryParts.join("; ")}.`,
  };
}

if (isMainModule()) {
  let result;
  try {
    result = collectProtocolEventCoverageErrors();
  } catch (error) {
    console.error(
      `Protocol event coverage check failed: ${error instanceof Error ? error.message : String(error)}`,
    );
    process.exit(1);
  }
  if (result.errors.length > 0) {
    console.error("Protocol event coverage check failed:");
    for (const error of result.errors) {
      console.error(`  - ${error}`);
    }
    process.exit(1);
  }
  console.log(`Protocol event coverage OK: ${result.summary}`);
}