tubestats-presentation/js/utils/util.js

280 lines
5.9 KiB
JavaScript

/**
* Extend object a with the properties of object b.
* If there's a conflict, object b takes precedence.
*
* @param {object} a
* @param {object} b
*/
export const extend = ( a, b ) => {
for( let i in b ) {
a[ i ] = b[ i ];
}
return a;
}
/**
* Converts the target object to an array.
*
* @param {object} o
* @return {object[]}
*/
export const toArray = ( o ) => {
return Array.prototype.slice.call( o );
}
/**
* Utility for deserializing a value.
*
* @param {*} value
* @return {*}
*/
export const deserialize = ( value ) => {
if( typeof value === 'string' ) {
if( value === 'null' ) return null;
else if( value === 'true' ) return true;
else if( value === 'false' ) return false;
else if( value.match( /^-?[\d\.]+$/ ) ) return parseFloat( value );
}
return value;
}
/**
* Measures the distance in pixels between point a
* and point b.
*
* @param {object} a point with x/y properties
* @param {object} b point with x/y properties
*
* @return {number}
*/
export const distanceBetween = ( a, b ) => {
let dx = a.x - b.x,
dy = a.y - b.y;
return Math.sqrt( dx*dx + dy*dy );
}
/**
* Applies a CSS transform to the target element.
*
* @param {HTMLElement} element
* @param {string} transform
*/
export const transformElement = ( element, transform ) => {
element.style.transform = transform;
}
/**
* Find the closest parent that matches the given
* selector.
*
* @param {HTMLElement} target The child element
* @param {String} selector The CSS selector to match
* the parents against
*
* @return {HTMLElement} The matched parent or null
* if no matching parent was found
*/
export const closestParent = ( target, selector ) => {
let parent = target.parentNode;
while( parent ) {
// There's some overhead doing this each time, we don't
// want to rewrite the element prototype but should still
// be enough to feature detect once at startup...
let matchesMethod = parent.matches || parent.matchesSelector || parent.msMatchesSelector;
// If we find a match, we're all set
if( matchesMethod && matchesMethod.call( parent, selector ) ) {
return parent;
}
// Keep searching
parent = parent.parentNode;
}
return null;
}
/**
* Converts various color input formats to an {r:0,g:0,b:0} object.
*
* @param {string} color The string representation of a color
* @example
* colorToRgb('#000');
* @example
* colorToRgb('#000000');
* @example
* colorToRgb('rgb(0,0,0)');
* @example
* colorToRgb('rgba(0,0,0)');
*
* @return {{r: number, g: number, b: number, [a]: number}|null}
*/
export const colorToRgb = ( color ) => {
let hex3 = color.match( /^#([0-9a-f]{3})$/i );
if( hex3 && hex3[1] ) {
hex3 = hex3[1];
return {
r: parseInt( hex3.charAt( 0 ), 16 ) * 0x11,
g: parseInt( hex3.charAt( 1 ), 16 ) * 0x11,
b: parseInt( hex3.charAt( 2 ), 16 ) * 0x11
};
}
let hex6 = color.match( /^#([0-9a-f]{6})$/i );
if( hex6 && hex6[1] ) {
hex6 = hex6[1];
return {
r: parseInt( hex6.substr( 0, 2 ), 16 ),
g: parseInt( hex6.substr( 2, 2 ), 16 ),
b: parseInt( hex6.substr( 4, 2 ), 16 )
};
}
let rgb = color.match( /^rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i );
if( rgb ) {
return {
r: parseInt( rgb[1], 10 ),
g: parseInt( rgb[2], 10 ),
b: parseInt( rgb[3], 10 )
};
}
let rgba = color.match( /^rgba\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\,\s*([\d]+|[\d]*.[\d]+)\s*\)$/i );
if( rgba ) {
return {
r: parseInt( rgba[1], 10 ),
g: parseInt( rgba[2], 10 ),
b: parseInt( rgba[3], 10 ),
a: parseFloat( rgba[4] )
};
}
return null;
}
/**
* Calculates brightness on a scale of 0-255.
*
* @param {string} color See colorToRgb for supported formats.
* @see {@link colorToRgb}
*/
export const colorBrightness = ( color ) => {
if( typeof color === 'string' ) color = colorToRgb( color );
if( color ) {
return ( color.r * 299 + color.g * 587 + color.b * 114 ) / 1000;
}
return null;
}
/**
* Handling the fullscreen functionality via the fullscreen API
*
* @see http://fullscreen.spec.whatwg.org/
* @see https://developer.mozilla.org/en-US/docs/DOM/Using_fullscreen_mode
*/
export const enterFullscreen = () => {
let element = document.documentElement;
// Check which implementation is available
let requestMethod = element.requestFullscreen ||
element.webkitRequestFullscreen ||
element.webkitRequestFullScreen ||
element.mozRequestFullScreen ||
element.msRequestFullscreen;
if( requestMethod ) {
requestMethod.apply( element );
}
}
/**
* Injects the given CSS styles into the DOM.
*
* @param {string} value
*/
export const injectStyleSheet = ( value ) => {
let tag = document.createElement( 'style' );
tag.type = 'text/css';
if( tag.styleSheet ) {
tag.styleSheet.cssText = value;
}
else {
tag.appendChild( document.createTextNode( value ) );
}
document.getElementsByTagName( 'head' )[0].appendChild( tag );
}
/**
* Loads a JavaScript file from the given URL and executes it.
*
* @param {string} url Address of the .js file to load
* @param {function} callback Method to invoke when the script
* has loaded and executed
*/
export const loadScript = ( url, callback ) => {
const script = document.createElement( 'script' );
script.type = 'text/javascript';
script.async = false;
script.defer = false;
script.src = url;
if( typeof callback === 'function' ) {
// Success callback
script.onload = script.onreadystatechange = event => {
if( event.type === 'load' || /loaded|complete/.test( script.readyState ) ) {
// Kill event listeners
script.onload = script.onreadystatechange = script.onerror = null;
callback();
}
};
// Error callback
script.onerror = err => {
// Kill event listeners
script.onload = script.onreadystatechange = script.onerror = null;
callback( new Error( 'Failed loading script: ' + script.src + '\n' + err ) );
};
}
// Append the script at the end of <head>
const head = document.querySelector( 'head' );
head.insertBefore( script, head.lastChild );
}