webm-duration-fix/src/ebml/EBML.ts

based on ts-ebml and support large file(than 2GB) and optimize memory usage during repair

export type ChildElementsValue = NumberElement | StringElement | BinaryElement | DateElement;
export type EBMLElementValue = MasterElement | ChildElementsValue;
export type ChildElementBuffer = ChildElement & {data: Buffer};
export type EBMLElementBuffer = MasterElement | ChildElementBuffer;
export type EBMLElementBufferValue = MasterElement | (ChildElementsValue & {data: Buffer});
export type EBMLElementDetail = (MasterElement | (ChildElementsValue & {data: Buffer}) ) & ElementDetail;

export interface IElement {
  name: string;
  type: "m"|"u"|"i"|"f"|"s"|"8"|"b"|"d"|"unknown";
}

export interface ChildElement extends IElement {
  type: "u"|"i"|"f"|"s"|"8"|"b"|"d"|"unknown";
}

export interface MasterElement extends IElement {
  type: "m" | "unknown";
  isEnd: boolean;
  unknownSize?: boolean;
}

export interface ChildElementValue extends ChildElement {
  value: any;
}

export interface NumberElement extends ChildElementValue {
  type: "u" | "i" | "f";
  value: number;
}

export interface StringElement extends ChildElementValue {
  type: "s" | "8";
  value: string;
}

export interface BinaryElement extends ChildElementValue {
  type: "b";
  value: Buffer;
}

export interface DateElement extends ChildElementValue {
  type: "d";
  /**
   * Date - signed 8 octets integer in nanoseconds with 0 indicating the precise
   * beginning of the millennium (at 2001-01-01T00:00:00,000000000 UTC)
   */
  value: Date; 
}


export interface ElementDetail {
  schema: Schema;
  /**
   * hex EBML ID
   */
  EBML_ID: string;
  /**
   * The level within an EBML tree that the element may occur at. 
   * + is for a recursive level (can be its own child). 
   * g: global element (can be found at any level)
   */
  level: number;
  /**
   * このタグのバッファ全体における開始オフセット位置
   */
  tagStart: number;
  /**
   * このタグのバッファ全体における終了オフセット位置
   */
  tagEnd: number;
  /**
   * size vint start
   */
  sizeStart: number;
  /**
   * size vint end
   */
  sizeEnd: number;
  /**
   * 要素の中身の開始位置
   */
  dataStart: number;
  /**
   * 要素の中身の終了位置
   */
  dataEnd: number;
  /**
   * dataEnd - dataStart
   */
  dataSize: number;
}

export interface SimpleBlock {
  discardable: boolean;
  frames: Buffer[];
  invisible: boolean;
  keyframe: boolean;
  timecode: number;
  trackNumber: number;
}

export interface Schema {
  name: string;
  level: number;
  type: string;
  description: string;
}