/*
* Teletype jQuery Plugin
* @version 0.1
*
* @author Steve Whiteley
* @see http://teletype.rocks
* @see https://github.com/stvwhtly/jquery-teletype-plugin
*
* Copyright (c) 2014 Steve Whiteley
* Dual licensed under the MIT or GPL Version 2 licenses.
*
*/
( function ( $ ) {
	$.fn.teletype = function( options ) {
		var settings = $.extend( {}, $.fn.teletype.defaults, options );
		var self = $( this ),
			output = null,
			current = { 
				string: '',
				index: 0,
				position: 0,
				loop: 0
			};
		var next = function() {
			current.index++;
			if ( current.index >= settings.text.length ) {
				current.index = 0;
				current.loop++;
				if ( settings.loop != false && ( settings.loop == current.loop ) ) {
					return false;
				}
			}
			current.position = 0;
			current.string = settings.text[current.index];
			return true;
		};
		var type = function() {
			if ( settings.prefix && current.position == 0 ) {
				if ( current.loop == 0 && current.index == 0 ) {
					$( '<span />' ).addClass( 'teletype-prefix' ).html( settings.prefix ).prependTo( self );
				}
			}
			var letters = current.string.split( '' ),
				letter = letters[current.position];
			if ( letter == '^' || letter == '~' ) {
				var end = current.string.substr( current.position + 1 ).indexOf( ' ' );
				var value = current.string.substr( current.position + 1, end );
				if ( $.isNumeric( value ) ) {
					current.string = current.string.replace( letter + value + ' ', '' );
					if ( letter == '^' ) {
						window.setTimeout( function() {
							window.setTimeout( type, delay( settings.typeDelay ) );
						}, value );
					} else {
						var index = current.position - value;
						current.string = current.string.substr( 0, index - 1 ) + current.string.substr( current.position - 1 );
						window.setTimeout( function() {
							backspace( Math.max( index, 0 ) );
						}, delay( settings.backDelay ) );
					}
					return;
				}
			} else if ( letter == '\\' ) {
				var nextChar = current.string.substr( current.position + 1, 1 );
				if ( nextChar  == 'n' ) {
					current.position++;
					letter = '<br />';
				}
			}
			output.html( output.html() + letter );
			current.position++;
			if ( current.position < current.string.length ) {
				window.setTimeout( type, delay( settings.typeDelay ) );
			} else if ( settings.preserve == false ) {
				window.setTimeout( function() {
					window.setTimeout( backspace, delay( settings.backDelay ) );
				}, settings.delay );
			} else {
				output.html( output.html() + '<br />' + '<span class="teletype-prefix">' + settings.prefix + '</span>' );
				if ( next() ) {
					window.setTimeout( function() {
						window.setTimeout( type, delay( settings.typeDelay ) );
					}, settings.delay );
				}
			}
		};
		var backspace = function( stop ) {
			if ( !stop ) {
				stop = 0;
			}
			if ( current.position > stop ) {
				output.html( output.html().slice( 0, -1 ) );
				window.setTimeout( function() {
					backspace( stop );
				}, delay( settings.backDelay ) );
				current.position--;
			} else {
				if ( stop == 0 ) {
					if ( next() == false ) {
						return;
					}
				}
				window.setTimeout( type, delay( settings.typeDelay ) );
			}
		};
		var delay = function( speed ) {
			return Math.floor( Math.random() * 200 ) + speed;
		};
		return this.each( function() {
			current.string = settings.text[current.index];
			self.addClass( 'teletype' ).empty();
			output = $( '<span />' ).addClass( 'teletype-text' ).appendTo( self );
			
			if ( settings.cursor ) {
				var cursor = $( '<span />' )
					.text( settings.cursor )
					.addClass( 'teletype-cursor' )
					.appendTo( self );
				setInterval ( function() {
					cursor.animate( { opacity: 0 } ).animate( { opacity: 1 } );
				}, settings.blinkSpeed );
			}
			type();
		} );
	};
	$.fn.teletype.defaults = {
		text: [ 'one', 'two', 'three' ],
		typeDelay: 100,
		backDelay: 50,
		blinkSpeed: 1000,
		delay: 2000,
		cursor: '|',
		preserve: false,
		prefix: '',
		loop: 0
	};
}( jQuery ) );