Source: lib/text/cue.js

/**
 * @license
 * Copyright 2016 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

goog.provide('shaka.text.Cue');
goog.provide('shaka.text.CueRegion');

/**
 * Creates a Cue object.
 *
 * @param {number} startTime
 * @param {number} endTime
 * @param {string} payload
 *
 * @implements {shaka.extern.Cue}
 * @constructor
 * @struct
 * @export
 */
shaka.text.Cue = function(startTime, endTime, payload) {
  const Cue = shaka.text.Cue;

  /**
   * @override
   * @exportInterface
   */
  this.startTime = startTime;

  /**
   * @override
   * @exportInterface
   */
  this.direction = Cue.direction.HORIZONTAL_LEFT_TO_RIGHT;

  /**
   * @override
   * @exportInterface
   */
  this.endTime = endTime;

  /**
   * @override
   * @exportInterface
   */
  this.payload = payload;

  /**
   * @override
   * @exportInterface
   */
  this.region = new shaka.text.CueRegion();

  /**
   * @override
   * @exportInterface
   */
  this.position = null;

  /**
   * @override
   * @exportInterface
   */
  this.positionAlign = Cue.positionAlign.AUTO;

  /**
   * @override
   * @exportInterface
   */
  this.size = 0;

  /**
   * @override
   * @exportInterface
   */
  this.textAlign = Cue.textAlign.CENTER;

  /**
   * @override
   * @exportInterface
   */
  this.writingMode = Cue.writingMode.HORIZONTAL_TOP_TO_BOTTOM;

  /**
   * @override
   * @exportInterface
   */
  this.lineInterpretation = Cue.lineInterpretation.LINE_NUMBER;

  /**
   * @override
   * @exportInterface
   */
  this.line = null;

  /**
   * @override
   * @exportInterface
   */
  this.lineHeight = '';

  /**
   * Line Alignment is set to start by default.
   * @override
   * @exportInterface
   */
  this.lineAlign = Cue.lineAlign.START;

  /**
   * Set the captions at the bottom of the text container by default.
   * @override
   * @exportInterface
   */
  this.displayAlign = Cue.displayAlign.AFTER;

  /**
   * @override
   * @exportInterface
   */
  this.color = '';

  /**
   * @override
   * @exportInterface
   */
  this.backgroundColor = '';

  /**
   * @override
   * @exportInterface
   */
  this.backgroundImage = '';

  /**
   * @override
   * @exportInterface
   */
  this.fontSize = '';

  /**
   * @override
   * @exportInterface
   */
  this.fontWeight = Cue.fontWeight.NORMAL;

  /**
   * @override
   * @exportInterface
   */
  this.fontStyle = Cue.fontStyle.NORMAL;

  /**
   * @override
   * @exportInterface
   */
  this.fontFamily = '';

  /**
   * @override
   * @exportInterface
   */
  this.textDecoration = [];

  /**
   * @override
   * @exportInterface
   */
  this.wrapLine = true;

  /**
   * @override
   * @exportInterface
   */
  this.id = '';

  /**
   * @override
   * @exportInterface
   */
  this.nestedCues = [];

  /**
   * @override
   * @exportInterface
   */
  this.spacer = false;
};


/**
 * Create a copy of the cue with the same properties.
 * @return {!shaka.text.Cue}
 * @suppress {checkTypes} since we must use [] and "in" with a struct type.
 */
shaka.text.Cue.prototype.clone = function() {
  const clone = new shaka.text.Cue(0, 0, '');

  for (const k in this) {
    clone[k] = this[k];

    // Make copies of array fields, but only one level deep.  That way, if we
    // change, for instance, textDecoration on the clone, we don't affect the
    // original.
    if (clone[k] && clone[k].constructor == Array) {
      clone[k] = /** @type {!Array} */(clone[k]).slice();
    }
  }

  return clone;
};


/**
 * Check if two Cues have all the same values in all properties.
 * @param {!shaka.text.Cue} cue1
 * @param {!shaka.text.Cue} cue2
 * @return {boolean}
 * @suppress {checkTypes} since we must use [] and "in" with a struct type.
 */
shaka.text.Cue.equal = function(cue1, cue2) {
  // Compare the start time, end time and payload of the cues first for
  // performance optimization.  We can avoid the more expensive recursive
  // checks if the top-level properties don't match.
  // See: https://github.com/google/shaka-player/issues/3018
  if (cue1.startTime != cue2.startTime || cue1.endTime != cue2.endTime ||
      cue1.payload != cue2.payload) {
    return false;
  }

  for (const k in cue1) {
    if (k == 'startTime' || k == 'endTime' || k == 'payload') {
      // Already compared.
    } else if (k == 'nestedCues') {
      if (!shaka.util.ArrayUtils.equal(
          cue1.nestedCues, cue2.nestedCues, shaka.text.Cue.equal)) {
        return false;
      }
    } else if (k == 'region' || k == 'cellResolution') {
      for (const k2 in cue1[k]) {
        if (cue1[k][k2] != cue2[k][k2]) {
          return false;
        }
      }
    } else if (Array.isArray(cue1[k])) {
      if (!shaka.util.ArrayUtils.equal(cue1[k], cue2[k])) {
        return false;
      }
    } else {
      if (cue1[k] != cue2[k]) {
        return false;
      }
    }
  }

  return true;
};


/**
 * @enum {string}
 * @export
 */
shaka.text.Cue.positionAlign = {
  'LEFT': 'line-left',
  'RIGHT': 'line-right',
  'CENTER': 'center',
  'AUTO': 'auto',
};


/**
 * @enum {string}
 * @export
 */
shaka.text.Cue.textAlign = {
  'LEFT': 'left',
  'RIGHT': 'right',
  'CENTER': 'center',
  'START': 'start',
  'END': 'end',
};


/**
 * Vertical alignments of the cues within their extents.
 * 'BEFORE' means displaying at the top of the captions container box, 'CENTER'
 *  means in the middle, 'BOTTOM' means at the bottom.
 * @enum {string}
 * @export
 */
shaka.text.Cue.displayAlign = {
  'BEFORE': 'before',
  'CENTER': 'center',
  'AFTER': 'after',
};


/**
 * @enum {string}
 * @export
 */
shaka.text.Cue.direction = {
  'HORIZONTAL_LEFT_TO_RIGHT': 'ltr',
  'HORIZONTAL_RIGHT_TO_LEFT': 'rtl',
};


/**
 * @enum {string}
 * @export
 */
shaka.text.Cue.writingMode = {
  'HORIZONTAL_TOP_TO_BOTTOM': 'horizontal-tb',
  'VERTICAL_LEFT_TO_RIGHT': 'vertical-lr',
  'VERTICAL_RIGHT_TO_LEFT': 'vertical-rl',
};


/**
 * @enum {number}
 * @export
 */
shaka.text.Cue.lineInterpretation = {
  'LINE_NUMBER': 0,
  'PERCENTAGE': 1,
};


/**
 * @enum {string}
 * @export
 */
shaka.text.Cue.lineAlign = {
  'CENTER': 'center',
  'START': 'start',
  'END': 'end',
};


/**
 * In CSS font weight can be a number, where 400 is normal and 700 is bold.
 * Use these values for the enum for consistency.
 * @enum {number}
 * @export
 */
shaka.text.Cue.fontWeight = {
  'NORMAL': 400,
  'BOLD': 700,
};


/**
 * @enum {string}
 * @export
 */
shaka.text.Cue.fontStyle = {
  'NORMAL': 'normal',
  'ITALIC': 'italic',
  'OBLIQUE': 'oblique',
};


/**
 * @enum {string}
 * @export
 */
shaka.text.Cue.textDecoration = {
  'UNDERLINE': 'underline',
  'LINE_THROUGH': 'lineThrough',
  'OVERLINE': 'overline',
};


/**
 * Creates a CueRegion object.
 *
 * @implements {shaka.extern.CueRegion}
 * @constructor
 * @struct
 * @export
 */
shaka.text.CueRegion = function() {
  const CueRegion = shaka.text.CueRegion;

  /**
   * @override
   * @exportInterface
   */
  this.id = '';

  /**
   * @override
   * @exportInterface
   */
  this.viewportAnchorX = 0;

  /**
   * @override
   * @exportInterface
   */
  this.viewportAnchorY = 0;

  /**
   * @override
   * @exportInterface
   */
  this.regionAnchorX = 0;

  /**
   * @override
   * @exportInterface
   */
  this.regionAnchorY = 0;

  /**
   * @override
   * @exportInterface
   */
  this.width = 100;

  /**
   * @override
   * @exportInterface
   */
  this.height = 100;

  /**
   * @override
   * @exportInterface
   */
  this.heightUnits = CueRegion.units.PERCENTAGE;

  /**
   * @override
   * @exportInterface
   */
  this.widthUnits = CueRegion.units.PERCENTAGE;

  /**
   * @override
   * @exportInterface
   */
  this.viewportAnchorUnits = CueRegion.units.PERCENTAGE;

  /**
   * @override
   * @exportInterface
   */
  this.scroll = CueRegion.scrollMode.NONE;
};


/**
 * @enum {number}
 * @export
 */
shaka.text.CueRegion.units = {
  'PX': 0,
  'PERCENTAGE': 1,
  'LINES': 2,
};


/**
 * @enum {string}
 * @export
 */
shaka.text.CueRegion.scrollMode = {
  'NONE': '',
  'UP': 'up',
};