/**
 * Attempt to re-color SVG icons used in the admin menu or the toolbar
 *
 * @output site-admin/js/svg-painter.js
 */

window.wp = window.wp || {};

wp.svgPainter = ( function( $, window, document, undefined ) {
	'use strict';
	var selector, base64, painter,
		colorscheme = {},
		elements = [];

	$(document).ready( function() {
		// detection for browser SVG capability
		if ( document.implementation.hasFeature( 'http://www.w3.org/TR/SVG11/feature#Image', '1.1' ) ) {
			$( document.body ).removeClass( 'no-svg' ).addClass( 'svg' );
			wp.svgPainter.init();
		}
	});

	/**
	 * Needed only for IE9
	 *
	 * Based on jquery.base64.js 0.0.3 - https://github.com/yckart/jquery.base64.js
	 *
	 * Based on: https://gist.github.com/Yaffle/1284012
	 *
	 * Copyright (c) 2012 Yannick Albert (http://yckart.com)
	 * Licensed under the MIT license
	 * http://www.opensource.org/licenses/mit-license.php
	 */
	base64 = ( function() {
		var c,
			b64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/',
			a256 = '',
			r64 = [256],
			r256 = [256],
			i = 0;

		function init() {
			while( i < 256 ) {
				c = String.fromCharCode(i);
				a256 += c;
				r256[i] = i;
				r64[i] = b64.indexOf(c);
				++i;
			}
		}

		function code( s, discard, alpha, beta, w1, w2 ) {
			var tmp, length,
				buffer = 0,
				i = 0,
				result = '',
				bitsInBuffer = 0;

			s = String(s);
			length = s.length;

			while( i < length ) {
				c = s.charCodeAt(i);
				c = c < 256 ? alpha[c] : -1;

				buffer = ( buffer << w1 ) + c;
				bitsInBuffer += w1;

				while( bitsInBuffer >= w2 ) {
					bitsInBuffer -= w2;
					tmp = buffer >> bitsInBuffer;
					result += beta.charAt(tmp);
					buffer ^= tmp << bitsInBuffer;
				}
				++i;
			}

			if ( ! discard && bitsInBuffer > 0 ) {
				result += beta.charAt( buffer << ( w2 - bitsInBuffer ) );
			}

			return result;
		}

		function btoa( plain ) {
			if ( ! c ) {
				init();
			}

			plain = code( plain, false, r256, b64, 8, 6 );
			return plain + '===='.slice( ( plain.length % 4 ) || 4 );
		}

		function atob( coded ) {
			var i;

			if ( ! c ) {
				init();
			}

			coded = coded.replace( /[^A-Za-z0-9\+\/\=]/g, '' );
			coded = String(coded).split('=');
			i = coded.length;

			do {
				--i;
				coded[i] = code( coded[i], true, r64, a256, 6, 8 );
			} while ( i > 0 );

			coded = coded.join('');
			return coded;
		}

		return {
			atob: atob,
			btoa: btoa
		};
	})();

	return {
		init: function() {
			painter = this;
			selector = $( '#adminmenu .wp-menu-image, #wpadminbar .ab-item' );

			this.setColors();
			this.findElements();
			this.paint();
		},

		setColors: function( colors ) {
			if ( typeof colors === 'undefined' && typeof window._wpColorScheme !== 'undefined' ) {
				colors = window._wpColorScheme;
			}

			if ( colors && colors.icons && colors.icons.base && colors.icons.current && colors.icons.focus ) {
				colorscheme = colors.icons;
			}
		},

		findElements: function() {
			selector.each( function() {
				var $this = $(this), bgImage = $this.css( 'background-image' );

				if ( bgImage && bgImage.indexOf( 'data:image/svg+xml;base64' ) != -1 ) {
					elements.push( $this );
				}
			});
		},

		paint: function() {
			// loop through all elements
			$.each( elements, function( index, $element ) {
				var $menuitem = $element.parent().parent();

				if ( $menuitem.hasClass( 'current' ) || $menuitem.hasClass( 'wp-has-current-submenu' ) ) {
					// paint icon in 'current' color
					painter.paintElement( $element, 'current' );
				} else {
					// paint icon in base color
					painter.paintElement( $element, 'base' );

					// set hover callbacks
					$menuitem.hover(
						function() {
							painter.paintElement( $element, 'focus' );
						},
						function() {
							// Match the delay from hoverIntent
							window.setTimeout( function() {
								painter.paintElement( $element, 'base' );
							}, 100 );
						}
					);
				}
			});
		},

		paintElement: function( $element, colorType ) {
			var xml, encoded, color;

			if ( ! colorType || ! colorscheme.hasOwnProperty( colorType ) ) {
				return;
			}

			color = colorscheme[ colorType ];

			// only accept hex colors: #101 or #101010
			if ( ! color.match( /^(#[0-9a-f]{3}|#[0-9a-f]{6})$/i ) ) {
				return;
			}

			xml = $element.data( 'wp-ui-svg-' + color );

			if ( xml === 'none' ) {
				return;
			}

			if ( ! xml ) {
				encoded = $element.css( 'background-image' ).match( /.+data:image\/svg\+xml;base64,([A-Za-z0-9\+\/\=]+)/ );

				if ( ! encoded || ! encoded[1] ) {
					$element.data( 'wp-ui-svg-' + color, 'none' );
					return;
				}

				try {
					if ( 'atob' in window ) {
						xml = window.atob( encoded[1] );
					} else {
						xml = base64.atob( encoded[1] );
					}
				} catch ( error ) {}

				if ( xml ) {
					// replace `fill` attributes
					xml = xml.replace( /fill="(.+?)"/g, 'fill="' + color + '"');

					// replace `style` attributes
					xml = xml.replace( /style="(.+?)"/g, 'style="fill:' + color + '"');

					// replace `fill` properties in `<style>` tags
					xml = xml.replace( /fill:.*?;/g, 'fill: ' + color + ';');

					if ( 'btoa' in window ) {
						xml = window.btoa( xml );
					} else {
						xml = base64.btoa( xml );
					}

					$element.data( 'wp-ui-svg-' + color, xml );
				} else {
					$element.data( 'wp-ui-svg-' + color, 'none' );
					return;
				}
			}

			$element.attr( 'style', 'background-image: url("data:image/svg+xml;base64,' + xml + '") !important;' );
		}
	};

})( jQuery, window, document );