import { Component } from "../Component";
import { SplineCurve } from '../paths/SplineCurve';

export declare type Frame = {
  t: number;
  eye: number[];
  look: number[];
  up: number[];
};

export declare type CameraPathConfiguration = {
  /** Optional ID, unique among all components in the parent {@link Scene}, generated automatically when omitted. */
  id?: string;
  /** Initial sequence of frames. */
  frames: Frame[];
};

/**
 * Defines a sequence of frames along which a {@link CameraPathAnimation} can animate a {@link Camera}.
 *
 */
export declare class CameraPath extends Component {
  /**
   * @constructor
   * @param {Component} [owner]  Owner component. When destroyed, the owner will destroy this CameraPath as well.
   * @param {CameraPathConfiguration} [cfg] Configuration
   */
  constructor(owner?: Component, cfg?: CameraPathConfiguration);

  /**
   * Gets the camera frames in this CameraPath.
   *
   * @returns {{t:Number, eye:Object, look:Object, up: Object}[]} The frames on this CameraPath.
   */
  get frames(): Frame[];

  /**
   * Gets the {@link SplineCurve} along which {@link Camera#eye} travels.
   * @returns {SplineCurve} The SplineCurve for {@link Camera#eye}.
   */
  get eyeCurve(): SplineCurve;

  /**
   * Gets the {@link SplineCurve} along which {@link Camera#look} travels.
   * @returns {SplineCurve} The SplineCurve for {@link Camera#look}.
   */
  get lookCurve(): SplineCurve;

  /**
   * Gets the {@link SplineCurve} along which {@link Camera#up} travels.
   * @returns {SplineCurve} The SplineCurve for {@link Camera#up}.
   */
  get upCurve(): SplineCurve;

  /**
   * Adds a frame to this CameraPath, given as the current position of the {@link Camera}.
   *
   * @param {Number} t Time instant for the new frame.
   */
  saveFrame(t: number): void;

  /**
   * Adds a frame to this CameraPath, specified as values for eye, look and up vectors at a given time instant.
   *
   * @param {Number} t Time instant for the new frame.
   * @param {Number[]} eye A three-element vector specifying the eye position for the new frame.
   * @param {Number[]} look A three-element vector specifying the look position for the new frame.
   * @param {Number[]} up A three-element vector specifying the up vector for the new frame.
   */
  addFrame(t: number, eye: number, look: number[], up: number[]): void;

  /**
   * Adds multiple frames to this CameraPath, each frame specified as a set of values for eye, look and up vectors at a given time instant.
   *
   * @param {{t:Number, eye:Object, look:Object, up: Object}[]} frames Frames to add to this CameraPath.
   */
  addFrames(frames: Frame[]): void;

  /**
   * Sets the position of the {@link Camera} to a position interpolated within this CameraPath at the given time instant.
   *
   * @param {Number} t Time instant.
   */
  loadFrame(t: number): void;

  /**
   * Gets eye, look and up vectors on this CameraPath at a given instant.
   *
   * @param {Number} t Time instant.
   * @param {Number[]} eye The eye position to update.
   * @param {Number[]} look The look position to update.
   * @param {Number[]} up The up vector to update.
   */
  sampleFrame(t: number, eye: number[], look: number[], up: number[]): void;

  /**
   * Given a total duration (in seconds) for this CameraPath, recomputes the time instant at each frame so that,
   * when animated by {@link CameraPathAnimation}, the {@link Camera} will move along the path at a constant rate.
   *
   * @param {Number} duration The total duration for this CameraPath.
   */
  smoothFrameTimes(duration: number): void;

   /**
   * Removes all frames from this CameraPath.
   */
   clearFrames(): void;
}