// ============================================================
// 3DTank WebSocket 伪造客户端
// 手动构造 Hash Request 并发送，捕获服务器响应
// 用法: node forge.js [session_name]
// ============================================================

const WebSocket = require('ws');
const fs = require('fs');
const path = require('path');

// ============================================================
// 协议编码器
// ============================================================

// 变长整数编码 (对应 g7g)
// n < 0x80:        1 byte
// n < 0x4000:      2 bytes [0x80|(n>>8), n&0xFF]
// n < 0x400000:    3 bytes [0xC0|(n>>16), (n>>8)&0xFF, n&0xFF]
function encodeVarint(n) {
  if (n < 0x80) {
    return Buffer.from([n & 0x7F]);
  } else if (n < 0x4000) {
    const i = 0x8000 | (n & 0x3FFF);
    return Buffer.from([(i >> 8) & 0xFF, i & 0xFF]);
  } else {
    const r = 0xC00000 | (n & 0x3FFFFF);
    return Buffer.from([(r >> 16) & 0xFF, (r >> 8) & 0xFF, r & 0xFF]);
  }
}

// 变长整数解码 (对应 h7g)
function decodeVarint(buf, offset) {
  const b0 = buf[offset];
  if ((b0 & 0x80) === 0) {
    return { value: b0 & 0x7F, nextOffset: offset + 1 };
  }
  const b1 = buf[offset + 1];
  if ((b0 & 0x40) === 0) {
    // 2 bytes
    return { value: ((b0 & 0x3F) << 8) | b1, nextOffset: offset + 2 };
  }
  // 3 bytes
  const b2 = buf[offset + 2];
  return { value: ((b0 & 0x3F) << 16) | (b1 << 8) | b2, nextOffset: offset + 3 };
}

// UTF-8 字符串编码 (对应 Qt.c7g)
function encodeString(str) {
  const utf8 = Buffer.from(str, 'utf8');
  return Buffer.concat([encodeVarint(utf8.length), utf8]);
}

// 字符串数组编码 (对应 Wt.c7g)
function encodeStringArray(arr) {
  const parts = [encodeVarint(arr.length)];
  for (const s of arr) {
    parts.push(encodeString(s));
  }
  return Buffer.concat(parts);
}

// 命令 ID 编码 (对应 nn.c7g — 1 字节 int8)
// 注意: 命令 ID 在此协议中是 1 字节, 不是 8 字节 int64!
function encodeCommandId(cmdId) {
  return Buffer.from([cmdId & 0xFF]);
}

// Nullmap 编码 (对应 w7g)
// 对于 0 个可选字段: 1 byte = 0x00
function encodeNullmap(bitCount, bitmap) {
  if (bitCount === 0) {
    return Buffer.from([0x00]);
  }
  if (bitCount <= 5) {
    // 1 byte: bits 在高位 (bit 3-7)
    const byte0 = bitmap[0] >>> 3;
    return Buffer.from([byte0 & 0xFF]);
  }
  if (bitCount <= 13) {
    // 2 bytes: flag 0x20 in first byte
    const b0 = ((bitmap[0] >>> 3) + 0x20) & 0xFF;
    const b1 = ((bitmap[1] >>> 3) + ((bitmap[0] << 5) & 0xFF)) & 0xFF;
    return Buffer.from([b0, b1]);
  }
  if (bitCount <= 21) {
    // 3 bytes: flag 0x40 in first byte
    const b0 = ((bitmap[0] >>> 3) + 0x40) & 0xFF;
    const b1 = ((bitmap[1] >>> 3) + ((bitmap[0] << 5) & 0xFF)) & 0xFF;
    const b2 = ((bitmap[2] >>> 3) + ((bitmap[1] << 5) & 0xFF)) & 0xFF;
    return Buffer.from([b0, b1, b2]);
  }
  // 对于更大的 nullmap, 使用扩展格式
  const byteCount = Math.ceil(bitCount / 8);
  if (bitCount <= 504) {
    // 1 length byte (with 0x80 flag) + data
    const lenByte = (byteCount + 0x80) & 0xFF;
    return Buffer.concat([Buffer.from([lenByte]), Buffer.from(bitmap.slice(0, byteCount))]);
  }
  // 3 length bytes (with 0xC00000 flag) + data
  const lenVal = byteCount + 0xC00000;
  return Buffer.concat([
    Buffer.from([(lenVal >> 16) & 0xFF, (lenVal >> 8) & 0xFF, lenVal & 0xFF]),
    Buffer.from(bitmap.slice(0, byteCount))
  ]);
}

// 帧编码 (对应 e7f)
// 帧 = [2或4字节长度(BE)][nullmap][payload]
function encodeFrame(payload, nullmap) {
  const length = nullmap.length + payload.length;
  if (length < 0x4000) {
    // 2-byte format
    return Buffer.concat([
      Buffer.from([(length >> 8) & 0xFF, length & 0xFF]),
      nullmap,
      payload
    ]);
  } else {
    // 4-byte format with 0x80 flag
    return Buffer.concat([
      Buffer.from([
        ((length >>> 24) & 0xFF) | 0x80,
        (length >>> 16) & 0xFF,
        (length >>> 8) & 0xFF,
        length & 0xFF
      ]),
      nullmap,
      payload
    ]);
  }
}

// 帧解码 (对应 f7f 的读取逻辑)
function decodeFrame(buf) {
  if (buf.length < 2) return null;
  const b0 = buf[0];
  let frameLength;
  let headerSize;
  let compressed = false;

  if ((b0 & 0x80) !== 0) {
    // 4-byte format
    if (buf.length < 4) return null;
    const b1 = buf[1], b2 = buf[2], b3 = buf[3];
    frameLength = (((b0 & 0x7F) << 24) | (b1 << 16) | (b2 << 8) | b3) >>> 0;
    if (b0 & 0x40) compressed = true; // compression flag
    headerSize = 4;
  } else {
    // 2-byte format
    const b1 = buf[1];
    frameLength = ((b0 & 0x3F) << 8) | b1;
    if (b0 & 0x40) compressed = true;
    headerSize = 2;
  }

  const totalFrameSize = headerSize + frameLength;
  if (buf.length < totalFrameSize) return null;

  const frameData = buf.slice(headerSize, totalFrameSize);
  return { frameData, headerSize, frameLength, compressed, totalFrameSize };
}

// 解码 nullmap (对应 x7g)
function decodeNullmap(buf, offset) {
  if (offset >= buf.length) return { nullmap: null, nextOffset: offset };
  const r = buf[offset++];

  if ((r & 0x80) !== 0) {
    // 大格式: bit 7 = 1
    let size;
    if ((r & 0x40) !== 0) {
      // 3-byte size
      const b1 = buf[offset++];
      const b2 = buf[offset++];
      size = (((r & 0x3F) << 16) | (b1 << 8) | b2) >>> 0;
    } else {
      // 1-byte size
      size = r & 0x3F;
    }
    // 读取 size 字节的 nullmap 数据
    const data = buf.slice(offset, offset + size);
    offset += size;
    return { nullmap: data, bitCount: size * 8, nextOffset: offset };
  }

  // 小格式: bit 7 = 0
  const tier = (r & 0x60) >>> 5;
  let bitCount;
  let data;

  switch (tier) {
    case 0: // 5 bits, 1 byte
      bitCount = 5;
      data = Buffer.from([r << 3]); // 移位到高位
      break;
    case 1: { // 13 bits, 2 bytes
      bitCount = 13;
      const b1 = buf[offset++];
      data = Buffer.from([
        (r + (b1 >>> 5)) & 0xFF,
        (b1 << 3) & 0xFF
      ]);
      break;
    }
    case 2: { // 21 bits, 3 bytes
      bitCount = 21;
      const b1 = buf[offset++];
      const b2 = buf[offset++];
      data = Buffer.from([
        (r + (b1 >>> 5)) & 0xFF,
        ((b1 << 3) + (b2 >>> 5)) & 0xFF,
        (b2 << 3) & 0xFF
      ]);
      break;
    }
    case 3: { // 29 bits, 4 bytes
      bitCount = 29;
      const b1 = buf[offset++];
      const b2 = buf[offset++];
      const b3 = buf[offset++];
      data = Buffer.from([
        (r + (b1 >>> 5)) & 0xFF,
        ((b1 << 3) + (b2 >>> 5)) & 0xFF,
        ((b2 << 3) + (b3 >>> 5)) & 0xFF,
        (b3 << 3) & 0xFF
      ]);
      break;
    }
  }

  return { nullmap: data, bitCount, nextOffset: offset };
}

// ============================================================
// Hash Request 构造
// ============================================================

// 命令 ID 常量 (对应 w.p7j_1 等)
const CMD_HASH_REQUEST = 1;
const CMD_HASH_RESPONSE = 2;
const CMD_OPEN_SPACE = 32;
const CMD_CLIENT_LOG = 32;

// 构造 Hash Request payload (对应 or.c7g + Li.c7g)
function buildHashRequest(paramNames, paramValues) {
  // 1. Command ID (1 字节) = CMD_HASH_REQUEST
  const cmdId = encodeCommandId(CMD_HASH_REQUEST);
  // 2. paramNames 字符串数组
  const names = encodeStringArray(paramNames);
  // 3. paramValues 字符串数组
  const values = encodeStringArray(paramValues);
  // nullmap: 0 个可选字段 → 1 byte 0x00
  const nullmap = encodeNullmap(0, null);
  const payload = Buffer.concat([cmdId, names, values]);
  return { payload, nullmap };
}

// 构造 ClientLog 命令 (对应 Fi.c7g)
// ClientLog = Bi(LogEntryType, string, string)
// 编码: [cmdId=32][logEntryType.ordinal(1字节)][string1][string2]
function buildClientLog(logType, str1, str2) {
  const cmdId = encodeCommandId(CMD_CLIENT_LOG);  // 1 byte = 32
  const typeByte = Buffer.from([logType & 0xFF]);  // LogEntryType ordinal
  const s1 = encodeString(str1);
  const s2 = encodeString(str2);
  const nullmap = encodeNullmap(0, null);  // 无可空字段
  const payload = Buffer.concat([cmdId, typeByte, s1, s2]);
  return { payload, nullmap };
}

// 默认 Hash Request 参数 (从 module_61860.js 提取)
function getDefaultParams() {
  return [
    ['lang', 'zh-CN'],
    ['browser_user_agent', 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36'],
    ['os', 'Win32'],
    ['device_type', 'DESKTOP'],
    ['client_type', 'DESKTOP'],
    ['hardware_concurrency', '8'],
    ['time_zone', 'Asia/Shanghai'],
    ['video_card', 'ANGLE (NVIDIA, NVIDIA GeForce RTX 3060 Direct3D11 vs_5_0 ps_5_0)'],
    ['mobile_device', 'false'],
    ['touchscreen_support', 'false'],
    ['client_version', 'e3b4a3f1c8b8ea24cddc91a30e51b6903d55c0c7'],
    ['ram_size', '16'],
  ];
}

// ============================================================
// 工具函数
// ============================================================

function hexDump(buffer, prefix = '') {
  const bytes = Buffer.isBuffer(buffer) ? buffer : Buffer.from(buffer);
  const lines = [];
  for (let i = 0; i < bytes.length; i += 16) {
    const chunk = bytes.slice(i, Math.min(i + 16, bytes.length));
    const hex = Array.from(chunk).map(b => b.toString(16).padStart(2, '0')).join(' ');
    const ascii = Array.from(chunk).map(b => (b >= 32 && b < 127) ? String.fromCharCode(b) : '.').join('');
    lines.push(`${prefix}${i.toString(16).padStart(8, '0')}  ${hex.padEnd(48)}  ${ascii}`);
  }
  return lines.join('\n');
}

// 尝试解码响应帧
function tryDecodeResponse(buf) {
  const frame = decodeFrame(buf);
  if (!frame) return null;

  const result = {
    frameLength: frame.frameLength,
    headerSize: frame.headerSize,
    compressed: frame.compressed,
    nullmap: null,
    payload: null,
    commands: []
  };

  let offset = 0;
  const frameData = frame.frameData;

  // 解码 nullmap
  const nm = decodeNullmap(frameData, offset);
  offset = nm.nextOffset;
  result.nullmap = nm.nullmap;

  // 剩余 = payload (可能包含多个命令)
  const payload = frameData.slice(offset);
  result.payload = payload;

  // 解码命令 (命令 ID = 1 字节, 然后是 body)
  let pOffset = 0;
  const cmdNames = { 1: 'Hash Request', 2: 'Hash Response', 32: 'Open Space' };

  while (pOffset < payload.length) {
    const cmdStart = pOffset;
    const cmdId = payload[pOffset++]; // 1 字节命令 ID
    const cmdInfo = { offset: cmdStart, commandId: cmdId, name: cmdNames[cmdId] || '未知', body: null };

    if (cmdId === 2) {
      // Hash Response: 32 字节 hash + 1 字节 boolean
      if (pOffset + 33 <= payload.length) {
        const hash = payload.slice(pOffset, pOffset + 32);
        const boolean = payload[pOffset + 32];
        cmdInfo.body = {
          hash: hash.toString('hex'),
          hashBytes: Array.from(hash),
          boolean: boolean !== 0
        };
        pOffset += 33;
      } else {
        cmdInfo.body = { error: 'Hash Response body 不完整', remaining: payload.length - pOffset };
        break;
      }
    } else if (cmdId === 32) {
      // Open Space: 8 字节 64位 Long (BIG_ENDIAN) = Space ID
      // 对应 Xt.d7g → n2t(): W(getInt32(n, BE), getInt32(n+4, BE)) = W(high, low)
      if (pOffset + 8 <= payload.length) {
        const spaceIdBuf = payload.slice(pOffset, pOffset + 8);
        // BIG_ENDIAN: high 在前, low 在后
        const high = spaceIdBuf.readInt32BE(0);
        const low = spaceIdBuf.readUInt32BE(4);
        // 组合成 64 位值 (JavaScript 无原生 int64, 用字符串表示)
        const spaceIdStr = (high * 0x100000000 + low).toString();
        cmdInfo.body = {
          rawHex: spaceIdBuf.toString('hex'),
          spaceIdHigh: high,
          spaceIdLow: low,
          spaceId: spaceIdStr
        };
        pOffset += 8;
      } else {
        cmdInfo.body = { error: 'Open Space body 不完整', remaining: payload.length - pOffset };
        break;
      }
    } else {
      // 未知命令, 记录剩余字节
      const bodyBytes = payload.slice(pOffset);
      cmdInfo.body = {
        rawHex: bodyBytes.toString('hex'),
        rawLength: bodyBytes.length
      };
      pOffset = payload.length;
    }

    result.commands.push(cmdInfo);
  }

  return result;
}

// ============================================================
// 主程序
// ============================================================

const sessionName = process.argv[2] || `forge_${Date.now()}`;
const sessionDir = path.join(__dirname, sessionName);

if (!fs.existsSync(sessionDir)) {
  fs.mkdirSync(sessionDir, { recursive: true });
}

const logFile = path.join(sessionDir, 'log.txt');
const logStream = fs.createWriteStream(logFile, { flags: 'w' });

function log(msg) {
  const line = `[${new Date().toISOString()}] ${msg}`;
  console.log(line);
  logStream.write(line + '\n');
}

function saveBinary(data, direction, seq) {
  const filename = `${direction}_${seq.toString().padStart(4, '0')}.bin`;
  const filepath = path.join(sessionDir, filename);
  fs.writeFileSync(filepath, data);
  return filename;
}

// 构造 Hash Request
const params = getDefaultParams();
const paramNames = params.map(p => p[0]);
const paramValues = params.map(p => p[1]);

log('=== 3DTank WebSocket 伪造客户端 ===');
log(`会话: ${sessionName}`);
log(`目录: ${sessionDir}`);
log('');

log('--- Hash Request 参数 ---');
params.forEach(([k, v]) => log(`  ${k} = ${v.length > 60 ? v.slice(0, 57) + '...' : v}`));
log('');

const { payload, nullmap } = buildHashRequest(paramNames, paramValues);
const frame = encodeFrame(payload, nullmap);

log('--- 编码结果 ---');
log(`Payload 长度: ${payload.length} 字节`);
log(`Nullmap: ${nullmap.toString('hex')} (${nullmap.length} 字节)`);
log(`Frame 总长: ${frame.length} 字节`);
log('');
log('Frame 十六进制:');
log(hexDump(frame));
log('');

// 连接参数
// 默认连真实服务器；加 --url ws://localhost:9091/ 可改为连本地中继/模拟服务器
const url = (() => {
  const I = process.argv.indexOf('--url');
  return I >= 0 && process.argv[I + 1] ? process.argv[I + 1] : 'wss://c1.3dtank.com:9090/';
})();
let recvSeq = 0;
let sendSeq = 0;
let hashRequestSent = false;
let clientLogSent = false;

log(`正在连接 ${url} ...`);

const ws = new WebSocket(url, {
  rejectUnauthorized: false,
  headers: {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
    'Origin': 'https://3dtank.com'
  }
});

ws.binaryType = 'arraybuffer';

ws.on('open', function open() {
  log('✓ 连接成功!');
  log('');

  // 发送 Hash Request
  log('>>> 发送 Hash Request...');
  const fname = saveBinary(frame, 'send', sendSeq++);
  log(`    已保存: ${fname}`);
  log(`    ${frame.length} 字节:`);
  log(hexDump(frame, '    '));
  log('');

  ws.send(frame, { binary: true, mask: true }, function(err) {
    if (err) {
      log(`✗ 发送失败: ${err.message}`);
    } else {
      hashRequestSent = true;
      log('✓ Hash Request 已发送');
      log('');
    }
  });
});

ws.on('message', function incoming(data) {
  const buf = Buffer.from(data);
  const fname = saveBinary(buf, 'recv', recvSeq++);
  log(`<<< 接收消息 #${recvSeq - 1} (${buf.length} 字节) -> ${fname}`);
  log(hexDump(buf, '    '));
  log('');

  // 尝试解码帧
  const decoded = tryDecodeResponse(buf);
  if (decoded) {
    log(`    帧解码:`);
    log(`      头部长度: ${decoded.headerSize} 字节`);
    log(`      帧体长度: ${decoded.frameLength} 字节`);
    log(`      压缩: ${decoded.compressed}`);
    log(`      Nullmap: ${decoded.nullmap ? decoded.nullmap.toString('hex') : 'null'} (${decoded.nullmap ? decoded.nullmap.length : 0} 字节)`);
    log(`      Payload 长度: ${decoded.payload ? decoded.payload.length : 0} 字节`);
    if (decoded.commands && decoded.commands.length > 0) {
      log(`      命令 (${decoded.commands.length} 个):`);
      decoded.commands.forEach((cmd, i) => {
        log(`        [${i}] offset=${cmd.offset} ID=${cmd.commandId} (${cmd.name})`);
        if (cmd.body) {
          if (cmd.body.hash) {
            log(`            hash: ${cmd.body.hash}`);
            log(`            boolean: ${cmd.body.boolean}`);
          } else if (cmd.body.spaceId !== undefined) {
            log(`            spaceId (BE int64): ${cmd.body.spaceId}`);
            log(`            high=${cmd.body.spaceIdHigh}, low=${cmd.body.spaceIdLow}`);
            log(`            raw: ${cmd.body.rawHex}`);
          } else if (cmd.body.rawHex) {
            log(`            body (${cmd.body.rawLength} 字节): ${cmd.body.rawHex}`);
          } else if (cmd.body.error) {
            log(`            错误: ${cmd.body.error}`);
          }
        }
      });
    }
    // 空 payload = ping/keepalive, 回复 pong (相同的空帧 00 01 00)
    if (decoded.payload && decoded.payload.length === 0) {
      const pong = Buffer.from([0x00, 0x01, 0x00]);
      const pongFname = saveBinary(pong, 'send', sendSeq++);
      log(`>>> 回复 Pong (ping 保持连接) -> ${pongFname}`);
      ws.send(pong, { binary: true, mask: true });
    }
    // 收到 Open Space 后发送 ClientLog (测试是否能保持连接)
    if (decoded.commands) {
      const hasOpenSpace = decoded.commands.some(c => c.commandId === 32 && c.body && c.body.spaceId !== undefined);
      if (hasOpenSpace && !clientLogSent) {
        clientLogSent = true;
        const { payload: clPayload, nullmap: clNullmap } = buildClientLog(0, 'client_ready', 'forge_test');
        const clFrame = encodeFrame(clPayload, clNullmap);
        const clFname = saveBinary(clFrame, 'send', sendSeq++);
        log(`>>> 发送 ClientLog (测试保活) -> ${clFname}`);
        log(`    ${clFrame.length} 字节: ${clFrame.toString('hex')}`);
        ws.send(clFrame, { binary: true, mask: true });
      }
    }
  }
  log('');
});

ws.on('close', function close(code, reason) {
  log('---');
  log(`✗ 连接关闭 (code=${code})`);
  if (reason && reason.length > 0) {
    log(`  原因: ${reason.toString()}`);
  }
  log(`  Hash Request 已发送: ${hashRequestSent}`);
  log(`  总共接收: ${recvSeq} 条消息`);
  log(`  总共发送: ${sendSeq} 条消息`);
  logStream.end();
});

ws.on('error', function error(err) {
  log(`✗ 错误: ${err.message}`);
  if (err.stack) log(err.stack);
  // 不在这里 end logStream, 让 close 事件处理
});

// 优雅退出
process.on('SIGINT', function() {
  log('---');
  log('用户中断，正在关闭...');
  if (ws.readyState === WebSocket.OPEN) ws.close();
  logStream.end();
  process.exit(0);
});

// 超时退出 (5 分钟)
setTimeout(() => {
  log('---');
  log('超时自动退出 (5 分钟)');
  if (ws.readyState === WebSocket.OPEN) ws.close();
  logStream.end();
  process.exit(0);
}, 5 * 60 * 1000);