export interface Box {
  left?: number;
  top?: number;
  width?: number;
  height?: number;
}

export function encodeBox(message: Box): Uint8Array {
  let bb = popByteBuffer();
  _encodeBox(message, bb);
  return toUint8Array(bb);
}

function _encodeBox(message: Box, bb: ByteBuffer): void {
  // optional float left = 1;
  let $left = message.left;
  if ($left !== undefined) {
    writeVarint32(bb, 13);
    writeFloat(bb, $left);
  }

  // optional float top = 2;
  let $top = message.top;
  if ($top !== undefined) {
    writeVarint32(bb, 21);
    writeFloat(bb, $top);
  }

  // optional float width = 3;
  let $width = message.width;
  if ($width !== undefined) {
    writeVarint32(bb, 29);
    writeFloat(bb, $width);
  }

  // optional float height = 4;
  let $height = message.height;
  if ($height !== undefined) {
    writeVarint32(bb, 37);
    writeFloat(bb, $height);
  }
}

export function decodeBox(binary: Uint8Array): Box {
  return _decodeBox(wrapByteBuffer(binary));
}

function _decodeBox(bb: ByteBuffer): Box {
  let message: Box = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // optional float left = 1;
      case 1: {
        message.left = readFloat(bb);
        break;
      }

      // optional float top = 2;
      case 2: {
        message.top = readFloat(bb);
        break;
      }

      // optional float width = 3;
      case 3: {
        message.width = readFloat(bb);
        break;
      }

      // optional float height = 4;
      case 4: {
        message.height = readFloat(bb);
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface Point {
  x?: number;
  y?: number;
}

export function encodePoint(message: Point): Uint8Array {
  let bb = popByteBuffer();
  _encodePoint(message, bb);
  return toUint8Array(bb);
}

function _encodePoint(message: Point, bb: ByteBuffer): void {
  // optional float x = 1;
  let $x = message.x;
  if ($x !== undefined) {
    writeVarint32(bb, 13);
    writeFloat(bb, $x);
  }

  // optional float y = 2;
  let $y = message.y;
  if ($y !== undefined) {
    writeVarint32(bb, 21);
    writeFloat(bb, $y);
  }
}

export function decodePoint(binary: Uint8Array): Point {
  return _decodePoint(wrapByteBuffer(binary));
}

function _decodePoint(bb: ByteBuffer): Point {
  let message: Point = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // optional float x = 1;
      case 1: {
        message.x = readFloat(bb);
        break;
      }

      // optional float y = 2;
      case 2: {
        message.y = readFloat(bb);
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface BallDetection {
  plane_position?: Point;
  annotation?: Box;
  interpolated?: boolean;
}

export function encodeBallDetection(message: BallDetection): Uint8Array {
  let bb = popByteBuffer();
  _encodeBallDetection(message, bb);
  return toUint8Array(bb);
}

function _encodeBallDetection(message: BallDetection, bb: ByteBuffer): void {
  // optional Point plane_position = 1;
  let $plane_position = message.plane_position;
  if ($plane_position !== undefined) {
    writeVarint32(bb, 10);
    let nested = popByteBuffer();
    _encodePoint($plane_position, nested);
    writeVarint32(bb, nested.limit);
    writeByteBuffer(bb, nested);
    pushByteBuffer(nested);
  }

  // optional Box annotation = 2;
  let $annotation = message.annotation;
  if ($annotation !== undefined) {
    writeVarint32(bb, 18);
    let nested = popByteBuffer();
    _encodeBox($annotation, nested);
    writeVarint32(bb, nested.limit);
    writeByteBuffer(bb, nested);
    pushByteBuffer(nested);
  }

  // optional bool interpolated = 3;
  let $interpolated = message.interpolated;
  if ($interpolated !== undefined) {
    writeVarint32(bb, 24);
    writeByte(bb, $interpolated ? 1 : 0);
  }
}

export function decodeBallDetection(binary: Uint8Array): BallDetection {
  return _decodeBallDetection(wrapByteBuffer(binary));
}

function _decodeBallDetection(bb: ByteBuffer): BallDetection {
  let message: BallDetection = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // optional Point plane_position = 1;
      case 1: {
        let limit = pushTemporaryLength(bb);
        message.plane_position = _decodePoint(bb);
        bb.limit = limit;
        break;
      }

      // optional Box annotation = 2;
      case 2: {
        let limit = pushTemporaryLength(bb);
        message.annotation = _decodeBox(bb);
        bb.limit = limit;
        break;
      }

      // optional bool interpolated = 3;
      case 3: {
        message.interpolated = !!readByte(bb);
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface RLEBallDetection {
  detection?: BallDetection;
  count?: number;
}

export function encodeRLEBallDetection(message: RLEBallDetection): Uint8Array {
  let bb = popByteBuffer();
  _encodeRLEBallDetection(message, bb);
  return toUint8Array(bb);
}

function _encodeRLEBallDetection(
  message: RLEBallDetection,
  bb: ByteBuffer,
): void {
  // optional BallDetection detection = 1;
  let $detection = message.detection;
  if ($detection !== undefined) {
    writeVarint32(bb, 10);
    let nested = popByteBuffer();
    _encodeBallDetection($detection, nested);
    writeVarint32(bb, nested.limit);
    writeByteBuffer(bb, nested);
    pushByteBuffer(nested);
  }

  // optional uint32 count = 2;
  let $count = message.count;
  if ($count !== undefined) {
    writeVarint32(bb, 16);
    writeVarint32(bb, $count);
  }
}

export function decodeRLEBallDetection(binary: Uint8Array): RLEBallDetection {
  return _decodeRLEBallDetection(wrapByteBuffer(binary));
}

function _decodeRLEBallDetection(bb: ByteBuffer): RLEBallDetection {
  let message: RLEBallDetection = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // optional BallDetection detection = 1;
      case 1: {
        let limit = pushTemporaryLength(bb);
        message.detection = _decodeBallDetection(bb);
        bb.limit = limit;
        break;
      }

      // optional uint32 count = 2;
      case 2: {
        message.count = readVarint32(bb) >>> 0;
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface RLEDetectionHistory {
  detections?: RLEBallDetection[];
}

export function encodeRLEDetectionHistory(
  message: RLEDetectionHistory,
): Uint8Array {
  let bb = popByteBuffer();
  _encodeRLEDetectionHistory(message, bb);
  return toUint8Array(bb);
}

function _encodeRLEDetectionHistory(
  message: RLEDetectionHistory,
  bb: ByteBuffer,
): void {
  // repeated RLEBallDetection detections = 1;
  let array$detections = message.detections;
  if (array$detections !== undefined) {
    for (let value of array$detections) {
      writeVarint32(bb, 10);
      let nested = popByteBuffer();
      _encodeRLEBallDetection(value, nested);
      writeVarint32(bb, nested.limit);
      writeByteBuffer(bb, nested);
      pushByteBuffer(nested);
    }
  }
}

export function decodeRLEDetectionHistory(
  binary: Uint8Array,
): RLEDetectionHistory {
  return _decodeRLEDetectionHistory(wrapByteBuffer(binary));
}

function _decodeRLEDetectionHistory(bb: ByteBuffer): RLEDetectionHistory {
  let message: RLEDetectionHistory = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // repeated RLEBallDetection detections = 1;
      case 1: {
        let limit = pushTemporaryLength(bb);
        let values = message.detections || (message.detections = []);
        values.push(_decodeRLEBallDetection(bb));
        bb.limit = limit;
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface DetectionHistory {
  detections?: BallDetection[];
}

export function encodeDetectionHistory(message: DetectionHistory): Uint8Array {
  let bb = popByteBuffer();
  _encodeDetectionHistory(message, bb);
  return toUint8Array(bb);
}

function _encodeDetectionHistory(
  message: DetectionHistory,
  bb: ByteBuffer,
): void {
  // repeated BallDetection detections = 1;
  let array$detections = message.detections;
  if (array$detections !== undefined) {
    for (let value of array$detections) {
      writeVarint32(bb, 10);
      let nested = popByteBuffer();
      _encodeBallDetection(value, nested);
      writeVarint32(bb, nested.limit);
      writeByteBuffer(bb, nested);
      pushByteBuffer(nested);
    }
  }
}

export function decodeDetectionHistory(binary: Uint8Array): DetectionHistory {
  return _decodeDetectionHistory(wrapByteBuffer(binary));
}

function _decodeDetectionHistory(bb: ByteBuffer): DetectionHistory {
  let message: DetectionHistory = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // repeated BallDetection detections = 1;
      case 1: {
        let limit = pushTemporaryLength(bb);
        let values = message.detections || (message.detections = []);
        values.push(_decodeBallDetection(bb));
        bb.limit = limit;
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface Path {
  start_frame?: number;
  end_frame?: number;
  detections?: BallDetection;
  rle_detections?: RLEBallDetection;
  not_present?: boolean;
}

export function encodePath(message: Path): Uint8Array {
  let bb = popByteBuffer();
  _encodePath(message, bb);
  return toUint8Array(bb);
}

function _encodePath(message: Path, bb: ByteBuffer): void {
  // optional uint32 start_frame = 1;
  let $start_frame = message.start_frame;
  if ($start_frame !== undefined) {
    writeVarint32(bb, 8);
    writeVarint32(bb, $start_frame);
  }

  // optional uint32 end_frame = 2;
  let $end_frame = message.end_frame;
  if ($end_frame !== undefined) {
    writeVarint32(bb, 16);
    writeVarint32(bb, $end_frame);
  }

  // optional BallDetection detections = 3;
  let $detections = message.detections;
  if ($detections !== undefined) {
    writeVarint32(bb, 26);
    let nested = popByteBuffer();
    _encodeBallDetection($detections, nested);
    writeVarint32(bb, nested.limit);
    writeByteBuffer(bb, nested);
    pushByteBuffer(nested);
  }

  // optional RLEBallDetection rle_detections = 4;
  let $rle_detections = message.rle_detections;
  if ($rle_detections !== undefined) {
    writeVarint32(bb, 34);
    let nested = popByteBuffer();
    _encodeRLEBallDetection($rle_detections, nested);
    writeVarint32(bb, nested.limit);
    writeByteBuffer(bb, nested);
    pushByteBuffer(nested);
  }

  // optional bool not_present = 5;
  let $not_present = message.not_present;
  if ($not_present !== undefined) {
    writeVarint32(bb, 40);
    writeByte(bb, $not_present ? 1 : 0);
  }
}

export function decodePath(binary: Uint8Array): Path {
  return _decodePath(wrapByteBuffer(binary));
}

function _decodePath(bb: ByteBuffer): Path {
  let message: Path = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // optional uint32 start_frame = 1;
      case 1: {
        message.start_frame = readVarint32(bb) >>> 0;
        break;
      }

      // optional uint32 end_frame = 2;
      case 2: {
        message.end_frame = readVarint32(bb) >>> 0;
        break;
      }

      // optional BallDetection detections = 3;
      case 3: {
        let limit = pushTemporaryLength(bb);
        message.detections = _decodeBallDetection(bb);
        bb.limit = limit;
        break;
      }

      // optional RLEBallDetection rle_detections = 4;
      case 4: {
        let limit = pushTemporaryLength(bb);
        message.rle_detections = _decodeRLEBallDetection(bb);
        bb.limit = limit;
        break;
      }

      // optional bool not_present = 5;
      case 5: {
        message.not_present = !!readByte(bb);
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface IdentifierHistory {
  ball_identifier?: number;
  paths?: Path[];
}

export function encodeIdentifierHistory(
  message: IdentifierHistory,
): Uint8Array {
  let bb = popByteBuffer();
  _encodeIdentifierHistory(message, bb);
  return toUint8Array(bb);
}

function _encodeIdentifierHistory(
  message: IdentifierHistory,
  bb: ByteBuffer,
): void {
  // optional uint32 ball_identifier = 1;
  let $ball_identifier = message.ball_identifier;
  if ($ball_identifier !== undefined) {
    writeVarint32(bb, 8);
    writeVarint32(bb, $ball_identifier);
  }

  // repeated Path paths = 2;
  let array$paths = message.paths;
  if (array$paths !== undefined) {
    for (let value of array$paths) {
      writeVarint32(bb, 18);
      let nested = popByteBuffer();
      _encodePath(value, nested);
      writeVarint32(bb, nested.limit);
      writeByteBuffer(bb, nested);
      pushByteBuffer(nested);
    }
  }
}

export function decodeIdentifierHistory(binary: Uint8Array): IdentifierHistory {
  return _decodeIdentifierHistory(wrapByteBuffer(binary));
}

function _decodeIdentifierHistory(bb: ByteBuffer): IdentifierHistory {
  let message: IdentifierHistory = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // optional uint32 ball_identifier = 1;
      case 1: {
        message.ball_identifier = readVarint32(bb) >>> 0;
        break;
      }

      // repeated Path paths = 2;
      case 2: {
        let limit = pushTemporaryLength(bb);
        let values = message.paths || (message.paths = []);
        values.push(_decodePath(bb));
        bb.limit = limit;
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface Shot {
  identifier_histories?: IdentifierHistory[];
}

export function encodeShot(message: Shot): Uint8Array {
  let bb = popByteBuffer();
  _encodeShot(message, bb);
  return toUint8Array(bb);
}

function _encodeShot(message: Shot, bb: ByteBuffer): void {
  // repeated IdentifierHistory identifier_histories = 3;
  let array$identifier_histories = message.identifier_histories;
  if (array$identifier_histories !== undefined) {
    for (let value of array$identifier_histories) {
      writeVarint32(bb, 26);
      let nested = popByteBuffer();
      _encodeIdentifierHistory(value, nested);
      writeVarint32(bb, nested.limit);
      writeByteBuffer(bb, nested);
      pushByteBuffer(nested);
    }
  }
}

export function decodeShot(binary: Uint8Array): Shot {
  return _decodeShot(wrapByteBuffer(binary));
}

function _decodeShot(bb: ByteBuffer): Shot {
  let message: Shot = {} as any;

  end_of_message: while (!isAtEnd(bb)) {
    let tag = readVarint32(bb);

    switch (tag >>> 3) {
      case 0:
        break end_of_message;

      // repeated IdentifierHistory identifier_histories = 3;
      case 3: {
        let limit = pushTemporaryLength(bb);
        let values =
          message.identifier_histories || (message.identifier_histories = []);
        values.push(_decodeIdentifierHistory(bb));
        bb.limit = limit;
        break;
      }

      default:
        skipUnknownField(bb, tag & 7);
    }
  }

  return message;
}

export interface Long {
  low: number;
  high: number;
  unsigned: boolean;
}

interface ByteBuffer {
  bytes: Uint8Array;
  offset: number;
  limit: number;
}

function pushTemporaryLength(bb: ByteBuffer): number {
  let length = readVarint32(bb);
  let limit = bb.limit;
  bb.limit = bb.offset + length;
  return limit;
}

function skipUnknownField(bb: ByteBuffer, type: number): void {
  switch (type) {
    case 0:
      while (readByte(bb) & 0x80) {}
      break;
    case 2:
      skip(bb, readVarint32(bb));
      break;
    case 5:
      skip(bb, 4);
      break;
    case 1:
      skip(bb, 8);
      break;
    default:
      throw new Error("Unimplemented type: " + type);
  }
}

function stringToLong(value: string): Long {
  return {
    low: value.charCodeAt(0) | (value.charCodeAt(1) << 16),
    high: value.charCodeAt(2) | (value.charCodeAt(3) << 16),
    unsigned: false,
  };
}

function longToString(value: Long): string {
  let low = value.low;
  let high = value.high;
  return String.fromCharCode(
    low & 0xffff,
    low >>> 16,
    high & 0xffff,
    high >>> 16,
  );
}

// The code below was modified from https://github.com/protobufjs/bytebuffer.js
// which is under the Apache License 2.0.

let f32 = new Float32Array(1);
let f32_u8 = new Uint8Array(f32.buffer);

let f64 = new Float64Array(1);
let f64_u8 = new Uint8Array(f64.buffer);

function intToLong(value: number): Long {
  value |= 0;
  return {
    low: value,
    high: value >> 31,
    unsigned: value >= 0,
  };
}

let bbStack: ByteBuffer[] = [];

function popByteBuffer(): ByteBuffer {
  const bb = bbStack.pop();
  if (!bb) return { bytes: new Uint8Array(64), offset: 0, limit: 0 };
  bb.offset = bb.limit = 0;
  return bb;
}

function pushByteBuffer(bb: ByteBuffer): void {
  bbStack.push(bb);
}

function wrapByteBuffer(bytes: Uint8Array): ByteBuffer {
  return { bytes, offset: 0, limit: bytes.length };
}

function toUint8Array(bb: ByteBuffer): Uint8Array {
  let bytes = bb.bytes;
  let limit = bb.limit;
  return bytes.length === limit ? bytes : bytes.subarray(0, limit);
}

function skip(bb: ByteBuffer, offset: number): void {
  if (bb.offset + offset > bb.limit) {
    throw new Error("Skip past limit");
  }
  bb.offset += offset;
}

function isAtEnd(bb: ByteBuffer): boolean {
  return bb.offset >= bb.limit;
}

function grow(bb: ByteBuffer, count: number): number {
  let bytes = bb.bytes;
  let offset = bb.offset;
  let limit = bb.limit;
  let finalOffset = offset + count;
  if (finalOffset > bytes.length) {
    let newBytes = new Uint8Array(finalOffset * 2);
    newBytes.set(bytes);
    bb.bytes = newBytes;
  }
  bb.offset = finalOffset;
  if (finalOffset > limit) {
    bb.limit = finalOffset;
  }
  return offset;
}

function advance(bb: ByteBuffer, count: number): number {
  let offset = bb.offset;
  if (offset + count > bb.limit) {
    throw new Error("Read past limit");
  }
  bb.offset += count;
  return offset;
}

function readBytes(bb: ByteBuffer, count: number): Uint8Array {
  let offset = advance(bb, count);
  return bb.bytes.subarray(offset, offset + count);
}

function writeBytes(bb: ByteBuffer, buffer: Uint8Array): void {
  let offset = grow(bb, buffer.length);
  bb.bytes.set(buffer, offset);
}

function readString(bb: ByteBuffer, count: number): string {
  // Sadly a hand-coded UTF8 decoder is much faster than subarray+TextDecoder in V8
  let offset = advance(bb, count);
  let fromCharCode = String.fromCharCode;
  let bytes = bb.bytes;
  let invalid = "\uFFFD";
  let text = "";

  for (let i = 0; i < count; i++) {
    let c1 = bytes[i + offset],
      c2: number,
      c3: number,
      c4: number,
      c: number;

    // 1 byte
    if ((c1 & 0x80) === 0) {
      text += fromCharCode(c1);
    }

    // 2 bytes
    else if ((c1 & 0xe0) === 0xc0) {
      if (i + 1 >= count) text += invalid;
      else {
        c2 = bytes[i + offset + 1];
        if ((c2 & 0xc0) !== 0x80) text += invalid;
        else {
          c = ((c1 & 0x1f) << 6) | (c2 & 0x3f);
          if (c < 0x80) text += invalid;
          else {
            text += fromCharCode(c);
            i++;
          }
        }
      }
    }

    // 3 bytes
    else if ((c1 & 0xf0) == 0xe0) {
      if (i + 2 >= count) text += invalid;
      else {
        c2 = bytes[i + offset + 1];
        c3 = bytes[i + offset + 2];
        if (((c2 | (c3 << 8)) & 0xc0c0) !== 0x8080) text += invalid;
        else {
          c = ((c1 & 0x0f) << 12) | ((c2 & 0x3f) << 6) | (c3 & 0x3f);
          if (c < 0x0800 || (c >= 0xd800 && c <= 0xdfff)) text += invalid;
          else {
            text += fromCharCode(c);
            i += 2;
          }
        }
      }
    }

    // 4 bytes
    else if ((c1 & 0xf8) == 0xf0) {
      if (i + 3 >= count) text += invalid;
      else {
        c2 = bytes[i + offset + 1];
        c3 = bytes[i + offset + 2];
        c4 = bytes[i + offset + 3];
        if (((c2 | (c3 << 8) | (c4 << 16)) & 0xc0c0c0) !== 0x808080)
          text += invalid;
        else {
          c =
            ((c1 & 0x07) << 0x12) |
            ((c2 & 0x3f) << 0x0c) |
            ((c3 & 0x3f) << 0x06) |
            (c4 & 0x3f);
          if (c < 0x10000 || c > 0x10ffff) text += invalid;
          else {
            c -= 0x10000;
            text += fromCharCode((c >> 10) + 0xd800, (c & 0x3ff) + 0xdc00);
            i += 3;
          }
        }
      }
    } else text += invalid;
  }

  return text;
}

function writeString(bb: ByteBuffer, text: string): void {
  // Sadly a hand-coded UTF8 encoder is much faster than TextEncoder+set in V8
  let n = text.length;
  let byteCount = 0;

  // Write the byte count first
  for (let i = 0; i < n; i++) {
    let c = text.charCodeAt(i);
    if (c >= 0xd800 && c <= 0xdbff && i + 1 < n) {
      c = (c << 10) + text.charCodeAt(++i) - 0x35fdc00;
    }
    byteCount += c < 0x80 ? 1 : c < 0x800 ? 2 : c < 0x10000 ? 3 : 4;
  }
  writeVarint32(bb, byteCount);

  let offset = grow(bb, byteCount);
  let bytes = bb.bytes;

  // Then write the bytes
  for (let i = 0; i < n; i++) {
    let c = text.charCodeAt(i);
    if (c >= 0xd800 && c <= 0xdbff && i + 1 < n) {
      c = (c << 10) + text.charCodeAt(++i) - 0x35fdc00;
    }
    if (c < 0x80) {
      bytes[offset++] = c;
    } else {
      if (c < 0x800) {
        bytes[offset++] = ((c >> 6) & 0x1f) | 0xc0;
      } else {
        if (c < 0x10000) {
          bytes[offset++] = ((c >> 12) & 0x0f) | 0xe0;
        } else {
          bytes[offset++] = ((c >> 18) & 0x07) | 0xf0;
          bytes[offset++] = ((c >> 12) & 0x3f) | 0x80;
        }
        bytes[offset++] = ((c >> 6) & 0x3f) | 0x80;
      }
      bytes[offset++] = (c & 0x3f) | 0x80;
    }
  }
}

function writeByteBuffer(bb: ByteBuffer, buffer: ByteBuffer): void {
  let offset = grow(bb, buffer.limit);
  let from = bb.bytes;
  let to = buffer.bytes;

  // This for loop is much faster than subarray+set on V8
  for (let i = 0, n = buffer.limit; i < n; i++) {
    from[i + offset] = to[i];
  }
}

function readByte(bb: ByteBuffer): number {
  return bb.bytes[advance(bb, 1)];
}

function writeByte(bb: ByteBuffer, value: number): void {
  let offset = grow(bb, 1);
  bb.bytes[offset] = value;
}

function readFloat(bb: ByteBuffer): number {
  let offset = advance(bb, 4);
  let bytes = bb.bytes;

  // Manual copying is much faster than subarray+set in V8
  f32_u8[0] = bytes[offset++];
  f32_u8[1] = bytes[offset++];
  f32_u8[2] = bytes[offset++];
  f32_u8[3] = bytes[offset++];
  return f32[0];
}

function writeFloat(bb: ByteBuffer, value: number): void {
  let offset = grow(bb, 4);
  let bytes = bb.bytes;
  f32[0] = value;

  // Manual copying is much faster than subarray+set in V8
  bytes[offset++] = f32_u8[0];
  bytes[offset++] = f32_u8[1];
  bytes[offset++] = f32_u8[2];
  bytes[offset++] = f32_u8[3];
}

function readDouble(bb: ByteBuffer): number {
  let offset = advance(bb, 8);
  let bytes = bb.bytes;

  // Manual copying is much faster than subarray+set in V8
  f64_u8[0] = bytes[offset++];
  f64_u8[1] = bytes[offset++];
  f64_u8[2] = bytes[offset++];
  f64_u8[3] = bytes[offset++];
  f64_u8[4] = bytes[offset++];
  f64_u8[5] = bytes[offset++];
  f64_u8[6] = bytes[offset++];
  f64_u8[7] = bytes[offset++];
  return f64[0];
}

function writeDouble(bb: ByteBuffer, value: number): void {
  let offset = grow(bb, 8);
  let bytes = bb.bytes;
  f64[0] = value;

  // Manual copying is much faster than subarray+set in V8
  bytes[offset++] = f64_u8[0];
  bytes[offset++] = f64_u8[1];
  bytes[offset++] = f64_u8[2];
  bytes[offset++] = f64_u8[3];
  bytes[offset++] = f64_u8[4];
  bytes[offset++] = f64_u8[5];
  bytes[offset++] = f64_u8[6];
  bytes[offset++] = f64_u8[7];
}

function readInt32(bb: ByteBuffer): number {
  let offset = advance(bb, 4);
  let bytes = bb.bytes;
  return (
    bytes[offset] |
    (bytes[offset + 1] << 8) |
    (bytes[offset + 2] << 16) |
    (bytes[offset + 3] << 24)
  );
}

function writeInt32(bb: ByteBuffer, value: number): void {
  let offset = grow(bb, 4);
  let bytes = bb.bytes;
  bytes[offset] = value;
  bytes[offset + 1] = value >> 8;
  bytes[offset + 2] = value >> 16;
  bytes[offset + 3] = value >> 24;
}

function readInt64(bb: ByteBuffer, unsigned: boolean): Long {
  return {
    low: readInt32(bb),
    high: readInt32(bb),
    unsigned,
  };
}

function writeInt64(bb: ByteBuffer, value: Long): void {
  writeInt32(bb, value.low);
  writeInt32(bb, value.high);
}

function readVarint32(bb: ByteBuffer): number {
  let c = 0;
  let value = 0;
  let b: number;
  do {
    b = readByte(bb);
    if (c < 32) value |= (b & 0x7f) << c;
    c += 7;
  } while (b & 0x80);
  return value;
}

function writeVarint32(bb: ByteBuffer, value: number): void {
  value >>>= 0;
  while (value >= 0x80) {
    writeByte(bb, (value & 0x7f) | 0x80);
    value >>>= 7;
  }
  writeByte(bb, value);
}

function readVarint64(bb: ByteBuffer, unsigned: boolean): Long {
  let part0 = 0;
  let part1 = 0;
  let part2 = 0;
  let b: number;

  b = readByte(bb);
  part0 = b & 0x7f;
  if (b & 0x80) {
    b = readByte(bb);
    part0 |= (b & 0x7f) << 7;
    if (b & 0x80) {
      b = readByte(bb);
      part0 |= (b & 0x7f) << 14;
      if (b & 0x80) {
        b = readByte(bb);
        part0 |= (b & 0x7f) << 21;
        if (b & 0x80) {
          b = readByte(bb);
          part1 = b & 0x7f;
          if (b & 0x80) {
            b = readByte(bb);
            part1 |= (b & 0x7f) << 7;
            if (b & 0x80) {
              b = readByte(bb);
              part1 |= (b & 0x7f) << 14;
              if (b & 0x80) {
                b = readByte(bb);
                part1 |= (b & 0x7f) << 21;
                if (b & 0x80) {
                  b = readByte(bb);
                  part2 = b & 0x7f;
                  if (b & 0x80) {
                    b = readByte(bb);
                    part2 |= (b & 0x7f) << 7;
                  }
                }
              }
            }
          }
        }
      }
    }
  }

  return {
    low: part0 | (part1 << 28),
    high: (part1 >>> 4) | (part2 << 24),
    unsigned,
  };
}

function writeVarint64(bb: ByteBuffer, value: Long): void {
  let part0 = value.low >>> 0;
  let part1 = ((value.low >>> 28) | (value.high << 4)) >>> 0;
  let part2 = value.high >>> 24;

  // ref: src/google/protobuf/io/coded_stream.cc
  let size =
    part2 === 0
      ? part1 === 0
        ? part0 < 1 << 14
          ? part0 < 1 << 7
            ? 1
            : 2
          : part0 < 1 << 21
            ? 3
            : 4
        : part1 < 1 << 14
          ? part1 < 1 << 7
            ? 5
            : 6
          : part1 < 1 << 21
            ? 7
            : 8
      : part2 < 1 << 7
        ? 9
        : 10;

  let offset = grow(bb, size);
  let bytes = bb.bytes;

  switch (size) {
    case 10:
      bytes[offset + 9] = (part2 >>> 7) & 0x01;
    case 9:
      bytes[offset + 8] = size !== 9 ? part2 | 0x80 : part2 & 0x7f;
    case 8:
      bytes[offset + 7] =
        size !== 8 ? (part1 >>> 21) | 0x80 : (part1 >>> 21) & 0x7f;
    case 7:
      bytes[offset + 6] =
        size !== 7 ? (part1 >>> 14) | 0x80 : (part1 >>> 14) & 0x7f;
    case 6:
      bytes[offset + 5] =
        size !== 6 ? (part1 >>> 7) | 0x80 : (part1 >>> 7) & 0x7f;
    case 5:
      bytes[offset + 4] = size !== 5 ? part1 | 0x80 : part1 & 0x7f;
    case 4:
      bytes[offset + 3] =
        size !== 4 ? (part0 >>> 21) | 0x80 : (part0 >>> 21) & 0x7f;
    case 3:
      bytes[offset + 2] =
        size !== 3 ? (part0 >>> 14) | 0x80 : (part0 >>> 14) & 0x7f;
    case 2:
      bytes[offset + 1] =
        size !== 2 ? (part0 >>> 7) | 0x80 : (part0 >>> 7) & 0x7f;
    case 1:
      bytes[offset] = size !== 1 ? part0 | 0x80 : part0 & 0x7f;
  }
}

function readVarint32ZigZag(bb: ByteBuffer): number {
  let value = readVarint32(bb);

  // ref: src/google/protobuf/wire_format_lite.h
  return (value >>> 1) ^ -(value & 1);
}

function writeVarint32ZigZag(bb: ByteBuffer, value: number): void {
  // ref: src/google/protobuf/wire_format_lite.h
  writeVarint32(bb, (value << 1) ^ (value >> 31));
}

function readVarint64ZigZag(bb: ByteBuffer): Long {
  let value = readVarint64(bb, /* unsigned */ false);
  let low = value.low;
  let high = value.high;
  let flip = -(low & 1);

  // ref: src/google/protobuf/wire_format_lite.h
  return {
    low: ((low >>> 1) | (high << 31)) ^ flip,
    high: (high >>> 1) ^ flip,
    unsigned: false,
  };
}

function writeVarint64ZigZag(bb: ByteBuffer, value: Long): void {
  let low = value.low;
  let high = value.high;
  let flip = high >> 31;

  // ref: src/google/protobuf/wire_format_lite.h
  writeVarint64(bb, {
    low: (low << 1) ^ flip,
    high: ((high << 1) | (low >>> 31)) ^ flip,
    unsigned: false,
  });
}