jQuery(function ($) {
	WP_Optimize_Premium = WP_Optimize_Premium();
});

/**
 * Main WP_Optimize_Premium - handle Premium features.
 */
var WP_Optimize_Premium = function() {
	var $ = jQuery,
		send_command = WP_Optimize.send_command,
		optimization_get_info = WP_Optimize.optimization_get_info,
		take_a_backup_with_updraftplus = WP_Optimize.take_a_backup_with_updraftplus,
		save_auto_backup_options = WP_Optimize.save_auto_backup_options,
		block_ui = wp_optimize.block_ui;

	/**
	 * Wrapper for send_command() using especially for unused images trash commands.
	 *
	 * @param {string}   action     The action to send
	 * @param {[type]}   data       Data to send
	 * @param {Function} callback   Will be called with the results
	 */
	function trash_manager_send_command(action, data, callback) {
		if (!data) {
			data = {};
		}

		data['images_trash_command'] = action;

		return send_command('images_trash_command', data, callback);
	}

	/**
	 * Returns true if settings tab active.
	 *
	 * @return {boolean}
	 */
	function is_tab_active(tab) {
		var is_active = $('#wp-optimize-wrap .nav-tab-wrapper .nav-tab-active').is(['#wp-optimize-nav-tab-', tab].join(''));
		return is_active;
	}

	/**
	 * Variables for image optimization.
	 */
	var unused_images_tab_container = $('#wp-optimize-nav-tab-wpo_images-unused-contents'),
		unused_images_section = $('#wpo-unused-images-section'),
		unused_image_sizes_section = $('#wpo-unused-image-sizes-section'),
		unused_images_container = $('#wpo_unused_images'),
		unused_images_trash_container = $('#wpo_unused_images_trash'),
		unused_images_view_images_btn = $('#wpo_unused_images_view_images_btn'),
		unused_images_view_trash_btn = $('#wpo_unused_images_view_trash_btn'),
		unused_images_before_scan_view_trash_btn = $('#wpo_scan_for_unused_images_trash_info > a'),
		restore_unused_images_from_trash_btn = $('#wpo_restore_unused_images_from_trash_btn'),
		remove_unused_images_btn = $('#wpo_remove_unused_images_btn'),
		move_unused_images_to_trash_btn = $('#wpo_move_unused_images_to_trash_btn'),
		remove_unused_images_from_trash_btn = $('#wpo_remove_unused_images_from_trash_btn'),
		remove_selected_sizes_btn = $('#wpo_remove_selected_sizes_btn'),
		unused_images_refresh_btn = $('#wpo_unused_images_refresh'),
		unused_image_sizes_refresh_btn = $('#wpo_unused_image_sizes_refresh'),
		unused_images_select_all_btn = $('#wpo_unused_images_select_all'),
		unused_images_select_none_btn = $('#wpo_unused_images_select_none'),
		scan_for_unused_images_btn = $('#wpo_scan_for_unused_images'),
		scan_for_unused_image_sizes_btn = $('#wpo_scan_for_unused_image_sizes'),
		sites_select_container = $('#wpo_unused_images_sites_select_container'),
		sites_select = $('#wpo_unused_images_sites_select'),
		take_a_backup_checkbox1 = $('#enable-auto-backup-2'),
		take_a_backup_checkbox2 = $('#enable-auto-backup-3'),
		// which elements we hide when images view container is empty
		hide_when_empty_view_elements = wpoptimize.sites.length > 1 ? [
			// for multisite we keep block with site selector visible
			$('#wpo_unused_images_loaded_count')
		] : [
			$('#wpo_unused_images_control_panel'),
			$('#wpo_unused_images_loaded_count')
		],

		// which elements we hide images trash view container is empty
		hide_when_empty_trash_view_elements = wpoptimize.sites.length > 1 ? [
			// multisite
			$('#wpo_unused_images_trash_loaded_count')
		] : [
			$('#wpo_unused_images_control_panel'),
			$('#wpo_unused_images_trash_loaded_count')
		],

		IMAGES_WORK_MODE = {
			DETECT_IMAGES: 'detect_unused_images',
			DETECT_SIZES: 'detect_images_sizes',
			DETECT_BOTH: 'detect_both'
		},
		IMAGES_LOAD_STATUS = {
			COMPLETE: 'complete',
			SUCCESS: 'success',
			FAILURE: 'failure',
			BUSY: 'busy'
		},
		IMAGES_EVENTS = {
			GET_INFO_START: 'optimization_get_info_images_start',
			GET_INFO_PROCESS: 'optimization_get_info_images',
			GET_INFO_PROCESS_XHR_UPDATE : 'optimization_get_info_xhr_images',
			GET_INFO_DONE: 'optimization_get_info_images_done',
			OPTIMIZATION_START: 'do_optimization_images_start',
			OPTIMIZATION_DONE: 'do_optimization_images_done'
		},

		unused_images_view = new WP_Optimize_Images_View({
			container: unused_images_container,
			no_images_found_message: wpoptimize.no_unused_images_found,
			related_elements: [
				$('.wpo-last-scan-info', unused_images_section),
				$('.wpo-unused-images-el'),
				$('.wpo-image-sizes-section'),
				$('#wpo_unused_images_loaded_count'),
				$('#wpo_unused_images_refresh')
			],
			row_action_buttons: [
				{
					'class': 'wpo_unused_images_move_to_trash_single button button-primary',
					'title': wpoptimize.trash,
					'hint' : wpoptimize.move_to_trash
				},
				{
					'class': 'wpo_unused_images_remove_single button button-link button-link-delete',
					'title': wpoptimize.delete,
					'hint' : wpoptimize.permanently_delete
				}
			],
			action_buttons: [
				remove_unused_images_btn,
				move_unused_images_to_trash_btn,
			],
			hide_when_empty: hide_when_empty_view_elements,
			loader_additional_html: '<a class="wpo-unused-images-cancel-scan" data-mode="'+IMAGES_WORK_MODE.DETECT_IMAGES+'">'+wpoptimize.cancel_scan+'</a>',
			load_next_page_callback: load_unused_images_next_page
		}),
		unused_images_trash_view = new WP_Optimize_Images_View({
			container: unused_images_trash_container,
			no_images_found_message: wpoptimize.no_unused_trash_images_found,
			related_elements: [
				$('.wpo-unused-images-trash-el'),
				$('#wpo_unused_images_trash_loaded_count'),
			],
			row_action_buttons: [
				{
					'class': 'wpo_unused_images_restore_from_trash_single button',
					'title': wpoptimize.restore,
					'hint' : wpoptimize.restore_from_trash
				},
				{
					'class': 'wpo_unused_images_remove_single_from_trash button button-primary',
					'title': wpoptimize.delete,
					'hint' : wpoptimize.permanently_delete
				}
			],
			action_buttons: [
				restore_unused_images_from_trash_btn,
				remove_unused_images_from_trash_btn
			],
			hide_when_empty: hide_when_empty_trash_view_elements,
			load_next_page_callback: load_unused_images_trash_next_page,
			onclear: function() {
				last_load_trash_status[get_selected_site()] = '';
			}
		}),

		unused_images_tab_loaded = false,
		optimization_checkbox_images_val = false,
		images_loaded_count = {},
		images_total_count = {},
		images_per_page = parseInt(wpoptimize.unused_images_per_page),

		images_trash_loaded_count = {},
		images_trash_total_count = {},

		last_load_status = {},
		last_load_trash_status = {},
		current_load_xhr = {}, // xhr objects for currently working unused images ajax requests.
		images_dimensions_btn = $("#images_dimensions"),
		images_dimensions_save_settings_btn = $("#image_dimensions_save_settings_btn"),
		images_dimensions_ignore_classes = $("#image_dimensions_ignore_classes"),
		images_dimensions_hidden_content = $("#image_dimensions_hidden_content");

	/**
	 * Called on images tab activated and load content if need.
	 *
	 * @return void
	 */
	function images_tab_activated() {
		if (unused_images_tab_loaded) return;
		unused_images_tab_loaded = true;

		unused_images_view.show();
		unused_images_trash_view.hide();

		// load initial information about unused images and sizes.
		load_unused_images(IMAGES_WORK_MODE.DETECT_BOTH, false, true);
	}

	/**
	 * Handle click on "Scan website for unused images" button.
	 */
	scan_for_unused_images_btn.on('click', function() {
		load_unused_images(IMAGES_WORK_MODE.DETECT_IMAGES, true);
	});

	/**
	 * Handle click on "Scan website for unused image sizes" button.
	 */
	scan_for_unused_image_sizes_btn.on('click', function() {
		load_unused_images(IMAGES_WORK_MODE.DETECT_SIZES, true);
	});

	/**
	 * Handle click on cancel button.
	 */
	unused_images_tab_container.on('click', '.wpo-unused-images-cancel-scan', function() {
		var btn = $(this),
			mode = btn.data('mode'),
			data =  {
				mode: mode,
				cancel: true
			},
			params = {
				optimization_id: 'images',
				data: data
			};

		if (btn.prop('disabled')) return;

		btn.prop('disabled', true);

		abort_unused_images_loading_request(mode);

		send_command('get_optimization_info', params, function(resp) {
			$(document).trigger(IMAGES_EVENTS.GET_INFO_DONE, params);
		})
		.always(function() {
			btn.prop('disabled', false);
		});

	});

	/**
	 * Abort current unused image loading request.
	 *
	 * @param {string} mode - one of IMAGES_WORK_MODE values.
	 */
	function abort_unused_images_loading_request(mode) {
		if (current_load_xhr.hasOwnProperty(mode)) {
			current_load_xhr[mode].abort();
			delete current_load_xhr[mode];
		}
	}

	/**
	 * Handle switch to unused images trash view
	 */
	unused_images_view_trash_btn.on('click', function() {
		if ($(this).prop('disabled')) return false;

		unused_images_view_trash_btn.hide();
		unused_images_view_images_btn.show();

		// if this view has new information then reload it.
		if (unused_images_view_trash_btn.data('dirty')) {
			unused_images_view_trash_btn.data('dirty', false);
			unused_images_trash_view.clear();
		}

		unused_images_view.hide();
		unused_images_trash_view.show();

		unused_images_tab_container.addClass('wpo-unused-images-trash-view');

		return false;
	});

	/**
	 * Handle switch to unused images view
	 */
	unused_images_view_images_btn.on('click', function() {
		if ($(this).prop('disabled')) return false;

		unused_images_view_images_btn.hide();
		unused_images_view_trash_btn.show();

		unused_images_trash_view.hide();
		unused_images_view.show();

		unused_images_tab_container.removeClass('wpo-unused-images-trash-view');

		// when trash was opened without unused images scanning.
		if (unused_images_view_images_btn.data('before-scan')) {
			jQuery('.wpo-unused-images-section-loaded').addClass('wpo_hidden');
			jQuery('.wpo-unused-images-section-unloaded').show();
			unused_images_view_images_btn.data('before-scan', false);
		}

		// if this view has new information then reload it.
		if (unused_images_view_images_btn.data('dirty')) {
			unused_images_view_images_btn.data('dirty', false);
			// refresh images list
			reload_unused_images(false);
		}

		return false;
	});

	/**
	 * Handle switching to unused images trash without site scanning for unused images.
	 */
	unused_images_before_scan_view_trash_btn.on('click', function() {
		jQuery('.wpo-unused-images-section-unloaded').hide();
		jQuery('.wpo-unused-images-section-loaded').removeClass('wpo_hidden');
		
		// show trash
		unused_images_view_trash_btn.trigger('click');
		// set flag to 'back to unused images list' button to know which UI show
		unused_images_view_images_btn.data('before-scan', true);
	});

	/**
	 * Handle images optimization get info start event.
	 */
	$(document).on(IMAGES_EVENTS.GET_INFO_START, function(event, params) {
		var mode = params && params.hasOwnProperty('mode') ? params.mode : '';

		unused_images_refresh_btn.prop('disabled', true);

		if (mode == IMAGES_WORK_MODE.DETECT_IMAGES) {
			$('.wpo_shade', unused_images_section).show();
			$('.wpo-shade-progress-message', unused_images_section).text('');
		}

		if (mode == IMAGES_WORK_MODE.DETECT_SIZES) {
			$('.wpo_shade', unused_image_sizes_section).show();
			$('.wpo_unused_images_loader', unused_image_sizes_section).show();
			$('.wpo-shade-progress-message', unused_image_sizes_section).text('');
		}

		disable_image_optimization_controls(true);
	});

	/**
	 * Handle images optimization get info process event.
	 */
	$(document).on(IMAGES_EVENTS.GET_INFO_PROCESS, function(event, message, meta) {
		var mode = meta && meta.hasOwnProperty('mode') ? meta.mode : '';

		if (mode == IMAGES_WORK_MODE.DETECT_IMAGES) {
			$('.wpo-shade-progress-message', unused_images_section).text(message);
			unused_images_view.loader_message(message);
		}

		if (mode == IMAGES_WORK_MODE.DETECT_IMAGES) {
			$('.wpo-shade-progress-message', unused_image_sizes_section).text(message);
		}

	});

	/**
	 * Handle images optimization get info xhr object update.
	 */
	$(document).on(IMAGES_EVENTS.GET_INFO_PROCESS_XHR_UPDATE, function(event, xhr, meta) {
		if (meta.hasOwnProperty('mode')) {
			current_load_xhr[meta.mode] = xhr;
		}
	});

	/**
	 * Handle images optimization get info done event.
	 */
	$(document).on(IMAGES_EVENTS.GET_INFO_DONE, function(event, data) {
		$('#wpo_unused_images_shade').remove();
		$('.wpo_unused_images_loader').hide();
		unused_images_refresh_btn.prop('disabled', false);

		var meta = get_meta_from_images_optimization_response(data),
			mode = (meta && meta.hasOwnProperty('mode')) ? meta.mode : (data && data.hasOwnProperty('data') && data.data.hasOwnProperty('mode')) ? data.data.mode : false,
			// if action is cancelled the don't update view.
			is_cancelled = (data && data.hasOwnProperty('data') && data.data.hasOwnProperty('cancel')) || mode && current_load_xhr.hasOwnProperty(mode) && current_load_xhr[mode].hasOwnProperty('statusText') && 'abort' == current_load_xhr[mode].statusText;

		if (IMAGES_WORK_MODE.DETECT_IMAGES == mode) {
			$('.wpo_shade', unused_images_section).hide();
			unused_images_view.hide_loader();

			if (!is_cancelled) {
				$('.wpo-unused-images-section-unloaded').hide();
				$('.wpo-unused-images-section-loaded').removeClass('wpo_hidden');
				handle_response_from_image_optimization(data, update_unused_images_view);
			}
		}

		if (IMAGES_WORK_MODE.DETECT_SIZES == mode) {
			$('.wpo_shade', unused_image_sizes_section).hide();

			if (!is_cancelled) {
				$('.wpo-unused-image-sizes-section-unloaded').hide();
				$('.wpo-unused-image-sizes-section-loaded').removeClass('wpo_hidden');
				handle_response_from_image_optimization(data, update_sizes_sidebar);
			}
		}

		if (IMAGES_WORK_MODE.DETECT_BOTH == mode) {
			var last_scan_images_key = ['last_scan_', IMAGES_WORK_MODE.DETECT_IMAGES].join(''),
				last_scan_sizes_key = ['last_scan_', IMAGES_WORK_MODE.DETECT_SIZES].join('');

			// if response has unused images last scan time value
			if (meta && meta[last_scan_images_key]) {
				$('.wpo-unused-images-section-unloaded').hide();
				$('.wpo-unused-images-section-loaded').removeClass('wpo_hidden');
				$('.wpo_shade', unused_images_section).hide();

				handle_response_from_image_optimization(data, update_unused_images_view);
			} else {
				if (meta.hasOwnProperty('trash_images_count') && meta.trash_images_count > 0) {
					$('#wpo_scan_for_unused_images_trash_info > span').text(meta.trash_images_count_message);
					$('#wpo_scan_for_unused_images_trash_info').css('display', 'block');
				}
			}

			// if response has unused image sizes last scan time value
			if (meta && meta[last_scan_sizes_key]) {
				$('.wpo-unused-image-sizes-section-unloaded').hide();
				$('.wpo-unused-image-sizes-section-loaded').removeClass('wpo_hidden');
				$('.wpo_shade', unused_image_sizes_section).hide();

				handle_response_from_image_optimization(data, update_sizes_sidebar);
			}
		}

		disable_image_optimization_controls(false);
	});

	/**
	 * Handle images optimization start event.
	 */
	$(document).on(IMAGES_EVENTS.OPTIMIZATION_START, function() {
		unused_images_tab_loaded = true;
		$('.wpo_unused_images_loader').show();
		disable_image_optimization_controls(true);
	});

	/**
	 * Handle images optimization done event.
	 */
	$(document).on(IMAGES_EVENTS.OPTIMIZATION_DONE, function(event, data) {
		$('.wpo_unused_images_loader').hide();
		disable_image_optimization_controls(false);
		handle_response_from_image_optimization(data, update_unused_images_view);
		alert(data.result.meta.removed_message);
	});

	/**
	 * Handle clicks on image optimization buttons.
	 */
	remove_unused_images_btn.on('click', function() {
		// if no unused imaged then exit.
		if (0 == $('#wpo_unused_images input[type="checkbox"]:checked').length) return;

		save_auto_backup_options();

		if (take_a_backup_checkbox1.is(':checked')) {
			take_a_backup_with_updraftplus(remove_selected_images, 'uploads');
		} else {
			remove_selected_images();
		}
	});

	/**
	 * Handle move images to trash button.
	 */
	move_unused_images_to_trash_btn.on('click', function() {
		// if no unused imaged then exit.
		if (0 == $('#wpo_unused_images input[type="checkbox"]:checked').length) return;

		save_auto_backup_options();

		if (take_a_backup_checkbox1.is(':checked')) {
			take_a_backup_with_updraftplus(move_unused_images_to_trash, 'uploads');
		} else {
			move_unused_images_to_trash();
		}
	});

	/**
	 * Move selected unused images to trash.
	 *
	 * @param {array} selected_images list of images.
	 */
	function move_unused_images_to_trash(selected_images) {
		disable_image_optimization_controls(true);

		if (!selected_images) selected_images = unused_images_view.get_selected_images();

		unused_images_view.show_custom_loader(wpoptimize.moving_selected_unused_images_to_trash);

		return trash_manager_send_command('move_images_to_trash', {
			images: selected_images
		}, function(resp) {
			alert(resp.message);
			disable_image_optimization_controls(false);
			unused_images_view.remove_selected_images();
			unused_images_view.hide_loader();

			// update loaded count when move to trash
			for (i in selected_images) {
				image_val = selected_images[i];
				blog_id = image_val.split('_').shift();

				images_loaded_count[blog_id]--;
				images_total_count[blog_id]--;
			}

			show_images_loaded_text(get_selected_site());
			unused_images_view.update_view();
			// set dirty flag for refresh unused images trash view when user switch on it.
			unused_images_view_trash_btn.data('dirty', true);
		});
	}

	/**
	 * Handle remove images from trash button.
	 */
	remove_unused_images_from_trash_btn.on('click', function() {
		// if no selected images then exit.
		if (0 == unused_images_trash_view.get_selected_images().length) return;

		save_auto_backup_options();

		if (take_a_backup_checkbox1.is(':checked')) {
			take_a_backup_with_updraftplus(remove_unused_images_from_trash, 'uploads');
		} else {
			remove_unused_images_from_trash();
		}
	});

	/**
	 * Remove selected unused images from trash.
	 */
	function remove_unused_images_from_trash(selected_images, dom_elements_to_remove) {
		disable_image_optimization_controls(true);

		if (!selected_images) selected_images = unused_images_trash_view.get_selected_images();

		unused_images_trash_view.show_custom_loader(wpoptimize.deleting_unused_images_from_trash);

		return trash_manager_send_command('remove_trash_images', {
			images: selected_images
		}, function(resp) {
			if (resp.error) {
				alert(resp.error);
			} else if (resp.message) {
				alert(resp.message);

				// if sent images elements then just remove them otherwise reload the trash
				if (dom_elements_to_remove) {
					dom_elements_to_remove.remove();
					update_images_trash_counters(get_selected_site(), - selected_images.length);
				} else {
					// refresh trash view.
					unused_images_trash_view.reload();
				}
			}

			unused_images_trash_view.hide_loader();
			disable_image_optimization_controls(false);
		});
	}

	/**
	 * Handle restore unused images from trash.
	 *
	 * @return {Array}
	 */
	restore_unused_images_from_trash_btn.on('click', function() {
		// if no selected images then exit.
		if (0 == unused_images_trash_view.get_selected_images().length) return;

		save_auto_backup_options();

		if (take_a_backup_checkbox1.is(':checked')) {
			take_a_backup_with_updraftplus(restore_unused_images_from_trash, 'uploads');
		} else {
			restore_unused_images_from_trash();
		}
	});

	/**
	 * Restore selected unused images from trash.
	 */
	function restore_unused_images_from_trash(selected_images, dom_elements_to_remove) {
		disable_image_optimization_controls(true);

		abort_unused_images_loading_request(IMAGES_WORK_MODE.DETECT_IMAGES);

		if (!selected_images) selected_images = unused_images_trash_view.get_selected_images();

		unused_images_trash_view.show_custom_loader(wpoptimize.restoring_selected_unused_images_from_trash);

		return trash_manager_send_command('restore_images_from_trash', {
			images: selected_images
		}, function(resp) {
			if (resp.error) {
				alert(resp.error);
			} else if (resp.message) {
				alert(resp.message);
				// set dirty flag for refresh unused images view when user switch on it.
				unused_images_view_images_btn.data('dirty', true);

				// if sent images elements then just remove them otherwise reload the trash
				if (dom_elements_to_remove) {
					dom_elements_to_remove.remove();
				} else {
					// refresh trash view.
					unused_images_trash_view.remove_selected_images();
				}

				unused_images_trash_view.load_next_page_if_need();

				update_images_trash_counters(get_selected_site(), - selected_images.length);
			}

			unused_images_trash_view.hide_loader();
			disable_image_optimization_controls(false);
		});
	}

	/**
	 * Update trash images counter.
	 *
	 * @param {int} blog_id
	 * @param {int} diff
	 */
	function update_images_trash_counters(blog_id, diff) {
		if (images_trash_loaded_count.hasOwnProperty(blog_id)) {
			images_trash_loaded_count[blog_id] += diff;
		}

		if (images_trash_total_count.hasOwnProperty(blog_id)) {
			images_trash_total_count[blog_id] += diff;
		}

		show_images_trash_loaded_text(blog_id);
	}

	/**
	 * Handle remove selected sizes button click.
	 */
	remove_selected_sizes_btn.on('click', function() {
		save_auto_backup_options();

		if (take_a_backup_checkbox2.is(':checked')) {
			take_a_backup_with_updraftplus(remove_selected_image_sizes);
		} else {
			remove_selected_image_sizes();
		}
	});

	/**
	 * Handle "Scan again" unused images click.
	 */
	unused_images_refresh_btn.on('click', function(e) {
		
		e.preventDefault();

		if ($(this).prop('disabled')) return;

		reload_unused_images(true);
	});

	/**
	 * Reload unused images.
	 *
	 * @param {boolead} forced - if true then all caches will be cleared before scanning.
	 */
	function reload_unused_images(forced) {
		// reset statuses for pagination.
		images_loaded_count = {};
		images_total_count = {};
		last_load_status = {};

		var params = {
			mode: IMAGES_WORK_MODE.DETECT_IMAGES
		};

		if (forced) {
			params['forced'] = true;
		}

		unused_images_view.show_loader();

		$(document).trigger(IMAGES_EVENTS.GET_INFO_START, params);
		// run get info request with.
		current_load_xhr[params.mode] = optimization_get_info($('.wpo-shade-progress-message'), 'images', params)
			.fail(function() {
				$(document).trigger(IMAGES_EVENTS.GET_INFO_DONE, params);
			});
	}

	/**
	 * Handle "Scan again" unused image sizes click.
	 */
	unused_image_sizes_refresh_btn.on('click', function(e) {

		e.preventDefault();

		if ($(this).prop('disabled')) return;

		var params = {
			forced: true,
			mode: IMAGES_WORK_MODE.DETECT_SIZES
		};

		$('.wpo_unused_images_loader', unused_image_sizes_section).show();

		$(document).trigger(IMAGES_EVENTS.GET_INFO_START, params);
		// run get info request with.
		optimization_get_info($('.wpo-shade-progress-message'), 'images', params)
			.fail(function() {
				$(document).trigger(IMAGES_EVENTS.GET_INFO_DONE, params);
			});
	});

	/**
	 * Handle select all images link click.
	 */
	unused_images_select_all_btn.on('click', function() {
		if (unused_images_view.is_visible()) unused_images_view.select_all();
		if (unused_images_trash_view.is_visible()) unused_images_trash_view.select_all();
	});

	/**
	 * Handle select none images link click.
	 */
	unused_images_select_none_btn.on('click', function() {
		if (unused_images_view.is_visible()) unused_images_view.select_none();
		if (unused_images_trash_view.is_visible()) unused_images_trash_view.select_none();
	});

	/**
	 * Handle click on images tab.
	 */
	$('#wp-optimize-nav-tab-wrapper__wpo_images .nav-tab').on('click', function() {
		if (is_tab_active('wpo_images-unused')) images_tab_activated();
	});

	if (is_tab_active('wpo_images-unused')) images_tab_activated();

	/**
	 * Disable images optimization controls (buttons, checkboxes).
	 *
	 * @param {boolean} disable - if true then disable controls, false - enable.
	 *
	 * @return void
	 */
	function disable_image_optimization_controls(disable) {
		var optimization_checkbox_images = $('#optimization_checkbox_images');

		$.each([
			remove_unused_images_btn,
			remove_selected_sizes_btn,
			$('#optimization_button_images_big'),
			$('#optimization_button_images_small'),
			optimization_checkbox_images,
			unused_images_refresh_btn,
			move_unused_images_to_trash_btn,
			restore_unused_images_from_trash_btn,
			remove_unused_images_from_trash_btn,
			unused_images_view_images_btn,
			unused_images_view_trash_btn
		], function(i, el) {
			el.prop('disabled', disable);
		});

		if (disable) {
			optimization_checkbox_images_val = optimization_checkbox_images.is(':checked');
			optimization_checkbox_images.prop('checked', false);
		} else {
			optimization_checkbox_images.prop('checked', optimization_checkbox_images_val);
			// enable action buttons only if any image selected
			unused_images_view.update_view();
			unused_images_trash_view.update_view();
		}
	}

	/**
	 * Load and show information about unused images or sizes.
	 *
	 * @param {string}  mode      one of IMAGES_WORK_MODE object values.
	 * @param {boolean} forced    if set to true then all caches will cleaned and site scanned again
	 * @param {boolean} quickinfo if set to true then only current information will returned without tasks queue processing.
	 * @return void
	 */
	function load_unused_images(mode, forced, quickinfo) {
		var params = {
			mode: mode
		};

		if (forced) {
			params['forced'] = forced;
		}

		if (quickinfo) {
			params['quickinfo'] = quickinfo;
		}

		$(document).trigger(IMAGES_EVENTS.GET_INFO_START, params);

		current_load_xhr[mode] = optimization_get_info($('.wpo-shade-progress-message'), 'images', params)
			.fail(function() {
				$(document).trigger(IMAGES_EVENTS.GET_INFO_DONE, params);
				scan_for_unused_images_btn.show();
			})
			.always(function() {
				delete current_load_xhr[mode];
			});

	}

	/**
	 * Load next images page for unused images.
	 *
	 * @return void
	 */
	function load_unused_images_next_page() {
		var blog_id = get_selected_site(),
			offset = images_loaded_count.hasOwnProperty(blog_id) ? images_loaded_count[blog_id] : 0;

		// this function is using with WP_Optimize_Images_View for loading following unused images
		// pages and we don't want to use it for load the first page. The first page is loading
		// when IMAGES_EVENTS.GET_INFO_DONE event triggered.
		if (0 == offset) return;

		if (last_load_status.hasOwnProperty(blog_id) && (IMAGES_LOAD_STATUS.BUSY === last_load_status[blog_id] || IMAGES_LOAD_STATUS.COMPLETE === last_load_status[blog_id])) return;

		$('#wpo_unused_images_loader_bottom').css('visibility', 'visible');

		last_load_status[blog_id] = IMAGES_LOAD_STATUS.BUSY;

		var data = {
				optimization_id: 'images',
				data: {
					mode: IMAGES_WORK_MODE.DETECT_IMAGES,
					blog_id: blog_id,
					length: images_per_page,
					offset: offset
				}
			};

		send_command('get_optimization_info', data, function(resp) {
			var loaded = append_images_from_response(resp.result.meta);

			show_images_loaded_text(get_selected_site());

			if (loaded == images_per_page) {
				last_load_status[blog_id] = IMAGES_LOAD_STATUS.SUCCESS;
			} else {
				last_load_status[blog_id] = IMAGES_LOAD_STATUS.COMPLETE;
			}

			$('#wpo_unused_images_loader_bottom').css('visibility', 'hidden');

			unused_images_view.update_view();
		})
			.fail(function() {
				last_load_status[blog_id] = IMAGES_LOAD_STATUS.FAILURE;

				$('#wpo_unused_images_loader_bottom').css('visibility', 'hidden');
			});
	}

	/**
	 * Load images from trash for selected blog and display it.
	 *
	 * @return {Object} jquery ajax object
	 */
	function load_unused_images_trash_next_page() {

		var blog_id = get_selected_site(),
			images_loaded = unused_images_trash_view.get_images_count(blog_id),
			offset = unused_images_trash_view.get_visible_images_count(blog_id);

		if (last_load_trash_status.hasOwnProperty(blog_id) && (IMAGES_LOAD_STATUS.BUSY === last_load_trash_status[blog_id] || IMAGES_LOAD_STATUS.COMPLETE === last_load_trash_status[blog_id])) return;

		last_load_trash_status[blog_id] = IMAGES_LOAD_STATUS.BUSY;

		$('#wpo_unused_images_loader_bottom').css('visibility', 'visible');

		if (0 == images_loaded) {
			$('.wpo_shade', unused_images_section).show();
			$('.wpo-shade-progress-message').html('');
			images_trash_loaded_count[blog_id] = 0;
		}

		return trash_manager_send_command('get_trash_images', {
			offset: offset,
			length: images_per_page,
			blog_id: blog_id
		}, function(resp) {

			$('#wpo_unused_images_loader_bottom').css('visibility', 'hidden');
			$('.wpo_shade', unused_images_section).hide();

			if (resp.errors) {
				alert(resp.errors.join("\n"));
				return;
			}

			var i, value, url, title;
			for (i in resp.images) {
				if (!resp.images.hasOwnProperty(i)) continue;
				value = resp.images[i][0];
				title = (resp.images[i].length > 1) ? [resp.images[i][0],' [id:', resp.images[i][1],' ]', ].join('') : resp.images[i][0];
				url = [resp.base_url, resp.images[i][0]].join('');
				unused_images_trash_view.append_image(blog_id, value, url, url, title, title);

				if (!images_trash_loaded_count.hasOwnProperty(blog_id)) images_trash_loaded_count[blog_id] = 0;
				images_trash_loaded_count[blog_id]++;
			}

			images_trash_total_count[blog_id] = resp.total;

			show_images_trash_loaded_text(get_selected_site());

			if (resp.images && resp.images.length === images_per_page) {
				last_load_trash_status[blog_id] = IMAGES_LOAD_STATUS.SUCCESS;
			} else {
				last_load_trash_status[blog_id] = IMAGES_LOAD_STATUS.COMPLETE;
			}

			unused_images_trash_view.update_view();
		});
	}

	/**
	 * Show count of loaded images for blog_id.
	 *
	 * @param {number} blog_id
	 *
	 * @return void
	 */
	function show_images_loaded_text(blog_id) {
		if (images_total_count.hasOwnProperty(blog_id) && images_total_count[blog_id] > 0) {
			var text = wpoptimize.x_of_x_images_loaded.replace('%1$s', images_loaded_count[blog_id]).replace('%2$s', images_total_count[blog_id]);
			$('#wpo_unused_images_loaded_count').text(text);
		} else {
			$('#wpo_unused_images_loaded_count').text('');
		}
	}

	/**
	 * Show count of loaded trashed images for blog_id.
	 *
	 * @param {number} blog_id
	 *
	 * @return void
	 */
	function show_images_trash_loaded_text(blog_id) {
		if (images_trash_total_count.hasOwnProperty(blog_id)) {
			var text = wpoptimize.x_of_x_images_loaded.replace('%1$s', images_trash_loaded_count[blog_id]).replace('%2$s', images_trash_total_count[blog_id]);
			$('#wpo_unused_images_trash_loaded_count').text(text);
		}
	}

	/**
	 * Get response.result.meta property if it exists.
	 *
	 * @param {object} response
	 *
	 * @return {object|boolean}
	 */
	function get_meta_from_images_optimization_response(response) {
		if (response.result && response.result.hasOwnProperty('meta') && response.result.meta) return response.result.meta;
		return false;
	}

	/**
	 * Check returned response from image optimization and call update view callback.
	 *
	 * @param {Object} response - response from image optimization.
	 * @param {Function} update_view_callback - callback function to update view.
	 *
	 * @return void
	 */
	function handle_response_from_image_optimization(response, update_view_callback) {
		var meta = get_meta_from_images_optimization_response(response);

		if (meta) {
			if (update_view_callback) update_view_callback(meta);
		} else {
			alert(wpoptimize.error_unexpected_response);
		}
	}

	/**
	 * Update images optimization tab view with data returned from images optimization.
	 *
	 * @param {Object} data - metadata returned from images optimization
	 *
	 * @return void
	 */
	function update_unused_images_view(data) {
		var new_images_loaded = !data.hasOwnProperty('removed_message');

		if (new_images_loaded) unused_images_container.text('');

		var last_scan_images_key = ['last_scan_', IMAGES_WORK_MODE.DETECT_IMAGES].join('');
		$('.wpo-last-scan-text', unused_images_section).text(data[last_scan_images_key]);

		if (data && data.hasOwnProperty('unused_images')) {
			var blog_id, blog_url = '', show_multisite_select = false, sites_select_old_value = sites_select.val();

			// append images to list from response.
			if (new_images_loaded) {
				append_images_from_response(data);
			}

			sites_select.html('');

			for (blog_id in data.unused_images) {
				if (!data.unused_images.hasOwnProperty(blog_id)) continue;

				if (data.images_loaded_info.hasOwnProperty(blog_id)) {
					images_total_count[blog_id] = data.images_loaded_info[blog_id].total;
				}

				// update multisite sites select options list.
				if (/* data.unused_images[blog_id].length && */ data.multisite) {
					show_multisite_select = true;
					blog_url = [data.sites[blog_id].domain, data.sites[blog_id].path].join('');

					sites_select.append(['<option value="', blog_id, '">', blog_url, (0 == data.unused_images[blog_id].length ? ' ('+wpoptimize.no_unused_images+')' : ''), '</option>'].join(''));
				}
			}

		}

		// if unused images was not found then hide "X of X images loaded" message and set status to complete.
		if (data && 0 === data.files) {
			// hide information about loaded images.
			images_total_count[get_selected_site()] = 0;
			// block loading next page of images.
			last_load_status[get_selected_site()] = IMAGES_LOAD_STATUS.COMPLETE;
		}

		// show or hide multisite select.
		if (show_multisite_select) {
			sites_select_container.show();

			// restore selected site value in the select/
			if (sites_select_old_value) sites_select.val(sites_select_old_value);

			filter_images_by_site(sites_select.val());
		} else {
			sites_select_container.hide();
		}

		// show images loaded text.
		show_images_loaded_text(get_selected_site());
	}

	/**
	 * Update information about sizes in the sidebar.
	 *
	 * @param data
	 *
	 * @return void
	 */
	function update_sizes_sidebar(data) {
		var last_scan_sizes_key = ['last_scan_', IMAGES_WORK_MODE.DETECT_SIZES].join('');
		$('.wpo-last-scan-text', unused_image_sizes_section).text(data[last_scan_sizes_key]);

		// show information in the sizes sidebar.
		show_sizes_list($('#registered_image_sizes'), get_array_items_by_key_value(data.image_sizes, 'used', true), wpoptimize.no_registered_image_sizes);
		show_sizes_list($('#unused_image_sizes'), get_array_items_by_key_value(data.image_sizes, 'used', false), wpoptimize.no_unused_image_sizes);

		// disable/enable button if sizes selected or not selected.
		$('#registered_image_sizes, #unused_image_sizes').on('change', 'input[type="checkbox"]', function() {
			update_remove_selected_button_state();
		});

		update_remove_selected_button_state();
	}

	/**
	 * Append images to the list returned from ajax request.
	 *
	 * @param {object} data
	 *
	 * @return {number}
	 */
	function append_images_from_response(data) {
		var i, blog_id = 0, base_url = '', admin_url = '', blog_url = '', unused_image = {}, count;

		for (blog_id in data.unused_images) {
			if (!data.unused_images.hasOwnProperty(blog_id)) continue;

			// save images loaded count text.
			if (data.images_loaded_info.hasOwnProperty(blog_id)) {
				images_total_count[blog_id] = data.images_loaded_info[blog_id].total;
			}

			base_url = data[['baseurl_', blog_id].join('')];
			admin_url = data[['adminurl_', blog_id].join('')];

			count = 0;

			for (i in data.unused_images[blog_id]) {
				if (!data.unused_images[blog_id].hasOwnProperty(i)) continue;

				count++;
				unused_image = data.unused_images[blog_id][i];

				if (data.multisite) {
					// set blog url to show on multisite image titles.
					blog_url = [data.sites[blog_id].domain, data.sites[blog_id].path].join('');
				}

				append_image_to_list(unused_image, base_url, admin_url, blog_id, blog_url);
			}

			// update loaded count.
			if (images_loaded_count.hasOwnProperty(blog_id)) {
				images_loaded_count[blog_id] += count;
			} else {
				images_loaded_count[blog_id] = count;
			}
		}

		// lazyload images.
		// $('.lazyload', unused_images_container).lazyload();

		return count;
	}

	/**
	 * Handle site change.
	 */
	sites_select.on('change', function() {
		var selected_site = get_selected_site();
		filter_images_by_site(selected_site);
		show_images_loaded_text(selected_site);
	});

	/**
	 * Filter images on site change.
	 *
	 * @param {number} blog_id
	 *
	 * @return {void}
	 */
	function filter_images_by_site(blog_id) {
		unused_images_view.filter_by_site(blog_id);
		
		if (unused_images_trash_view.is_visible()) {
			unused_images_trash_view.reload();
		}
	}

	/**
	 * Return array of items from array where array[i].key == value.
	 *
	 * @param array
	 * @param key
	 * @param value
	 *
	 * @return {Array}
	 */
	function get_array_items_by_key_value(array, key, value) {
		var i, result = [];

		for (i in array) {
			if (!array.hasOwnProperty(i)) continue;
			if (array[i].hasOwnProperty(key) && value == array[i][key]) {
				result[i] = array[i];
			}
		}

		return result;
	}

	/**
	 * Output list of sizes with checkboxes to container.
	 *
	 * @param {Object} container 		 - jquery container.
	 * @param {Object} sizes 			 - list of image sizes.
	 * @param {string} not_found_message - message to show if sizes list is empty.
	 *
	 * @return void
	 */
	function show_sizes_list(container, sizes, not_found_message) {
		var i,
			empty = true,
			original_unscaled = 'wpo-original-unscaled';
		
		container.text('');
		if (sizes) {

			// if there are any original images with scaled versions, display their information first.
			if (sizes.hasOwnProperty(original_unscaled)) {
				container.append(['<label for="chk_',original_unscaled,'" class="unused-image-sizes__label"><input type="checkbox" id="chk_',original_unscaled,'" class="unused-image-sizes" name="',original_unscaled,'">',wpoptimize.original_if_scaled_version_exist,' (',sizes[original_unscaled].size_formatted,' - Total: ',sizes[original_unscaled].files,')</lalbel><br>'].join(''));
			}

			for (i in sizes) {
				if (original_unscaled === i) continue;
				if (sizes.hasOwnProperty(i)) {
					container.append(['<label for="chk_',i,'" class="unused-image-sizes__label"><input type="checkbox" id="chk_',i,'" class="unused-image-sizes" name="',i,'">',i,' (',sizes[i].size_formatted,' - Total: ',sizes[i].files,')</lalbel><br>'].join(''));
					empty = false;
				}
			}
		}

		if (empty) {
			$('.hide_on_empty', container.parent()).hide();
			container.append(['<i>', not_found_message,'</i>'].join(''));
		} else {
			$('.hide_on_empty', container.parent()).show();
		}

	}

	/**
	 * Append unused image to list.
	 *
	 * @param {string} image 	 - relative path to image or object {id: 'image id', url: 'relative url'}.
	 * @param {string} base_url  - url to images upload directory.
	 * @param {string} admin_url - url to images upload directory.
	 * @param {int}    blog_id   - blog id for the image
	 * @param {string} blog_url  - url for image blog, used in image title.
	 *
	 * @return void
	 */
	function append_image_to_list(image, base_url, admin_url, blog_id, blog_url) {
		var value = [blog_id, (image.id ? image.id : image.orig_url)].join('_'),
			href = image.id ? [admin_url, 'post.php?post=', image.id,'&action=edit'].join('') : [base_url, '/', image.url].join(''),
			title = image.id ? ['#', image.id].join('') : image.url,
			thumbnail_url = [base_url,'/',image.url].join(''),
			row_file_text = [base_url,'/',((image.id && image.url) ? image.url.replace(/(\-[0-9]+x[0-9]+)(\.[a-z]+)$/i, '$2') : image.url), (image.id ? [' [id: ',image.id,']'].join('') : '')].join('');

		// add blog_url to title on multisite.
		if (blog_url) title = [title, ' [',blog_url,']'].join('');

		unused_images_view.append_image(blog_id, value, href, thumbnail_url, title, row_file_text);
	}

	/**
	 * Handle changing unused images view action.
	 */
	$('.wpo_unused_images_switch_view a').on('click', function() {
		switch_view_unused_images($(this).data('mode'));
	});

	/**
	 * Handle remove single image
	 */
	unused_images_container.on('click', '.wpo_unused_images_remove_single', function() {
		var btn = $(this),
			image_item = btn.closest('.wpo_unused_image'),
			image_value = $('input[type="checkbox"]', image_item).attr('value');

		$('button', image_item).prop('disabled', true);
		remove_selected_images_command([image_value]).done(function() {
			image_item.remove();
		});
	});

	/**
	 * Handle move single image to the trash action
	 */
	unused_images_container.on('click', '.wpo_unused_images_move_to_trash_single', function() {
		var btn = $(this),
			image_item = btn.closest('.wpo_unused_image'),
			image_value = $('input[type="checkbox"]', image_item).attr('value');

		$('button', image_item).prop('disabled', true);
		move_unused_images_to_trash([image_value]).done(function() {
			image_item.remove();
		});
	});

	/**
	 * Handle restore single image from the trash action
	 */
	unused_images_trash_container.on('click', '.wpo_unused_images_restore_from_trash_single', function() {
		var btn = $(this),
			image_item = btn.closest('.wpo_unused_image'),
			image_value = $('input[type="checkbox"]', image_item).attr('value');

		$('button', image_item).prop('disabled', true);
		restore_unused_images_from_trash([image_value], image_item).done(function() {
			image_item.remove();
		});
	});

	/**
	 * Handle remove permanently single image from the trash action
	 */
	unused_images_trash_container.on('click', '.wpo_unused_images_remove_single_from_trash', function() {
		var btn = $(this),
			image_item = btn.closest('.wpo_unused_image'),
			image_value = $('input[type="checkbox"]', image_item).attr('value');

		$('button', image_item).prop('disabled', true);
		remove_unused_images_from_trash([image_value], image_item).done(function() {
			image_item.remove();
		});
	});

	/**
	 * Change unused images view between grid and list.
	 *
	 * @param mode
	 *
	 * @return void
	 */
	function switch_view_unused_images(mode) {
		unused_images_view.switch_view_mode(mode);
		unused_images_trash_view.switch_view_mode(mode);
	}

	/**
	 * Get selected images and call ajax request to remove them.
	 *
	 * @return void
	 */
	function remove_selected_images() {
		var selected_images = [];

		// if all images selected then set 'all'.
		if (0 == $('#wpo_unused_images input:not(:checked)').length && IMAGES_LOAD_STATUS.COMPLETE == last_load_status[get_selected_site()]) {
			selected_images = 'all';
		} else {
			selected_images = unused_images_view.get_selected_images();
		}

		// if no selected images then exit.
		if (0 == selected_images.length) return;

		remove_selected_images_command(selected_images);
	}

	/**
	 * Run unused images optimization for selected images.
	 *
	 * @param {array} selected_images
	 *
	 * @return {object}
	 */
	function remove_selected_images_command(selected_images) {
		$(document).trigger(IMAGES_EVENTS.OPTIMIZATION_START);
		unused_images_view.show_custom_loader(wpoptimize.deleting_selected_unused_images);

		return send_command('do_optimization', { optimization_id: 'images', data: { selected_images: selected_images, images_loaded: images_loaded_count} }, function(resp) {
			// remove checked images.
			var i,
				image_inp,
				image_val,
				blog_id;

			for (i in selected_images) {
				if (!selected_images.hasOwnProperty(i)) continue;

				image_val = selected_images[i];
				image_inp = $(['#wpo_unused_images input[value="',image_val,'"'].join(''));
				blog_id = image_val.split('_').shift();

				// update loaded count
				images_loaded_count[blog_id]--;
				images_total_count[blog_id]--;
				image_inp.closest('.wpo_unused_image').remove();
			}

			$(document).trigger(IMAGES_EVENTS.OPTIMIZATION_DONE, resp);
			unused_images_view.hide_loader();
			// trigger load next page of images if need.
			unused_images_view.load_next_page_if_need();
		})
		.fail(function() {
			unused_images_view.hide_loader();
			alert(wpoptimize.error_unexpected_response);
		});
	}

	/**
	 * Returns list of selected image sizes by user.
	 *
	 * @return {array} list of image sizes.
	 */
	function get_selected_image_sizes() {
		var selected_sizes = [];
		$('#registered_image_sizes input[type="checkbox"], #unused_image_sizes input[type="checkbox"]').each(function() {
			var checkbox = $(this);
			if (checkbox.is(':checked')) selected_sizes.push(checkbox.prop('name'));
		});

		return selected_sizes;
	}

	/**
	 * Do ajax action to remove image by sizes list.
	 *
	 * @param {array} sizes - list of image sizes.
	 *
	 * @return void
	 */
	function remove_selected_image_sizes() {

		var sizes = get_selected_image_sizes();

		if (remove_selected_sizes_btn.prop('disabled') || !sizes || 0 == sizes.length) return;

		var registered_image_sizes_container = $('#registered_image_sizes'),
			unused_image_sizes_container = $('#unused_image_sizes'),
			sizes_section_container = registered_image_sizes_container.parent(),
			loaders = $('.wpo_unused_images_loader', sizes_section_container);

		disable_image_optimization_controls(true);
		loaders.show();

		send_command('do_optimization', { optimization_id: 'images', data: { selected_sizes: sizes } }, function(resp) {
			handle_response_from_image_optimization(resp, function(data) {
				show_sizes_list(registered_image_sizes_container, get_array_items_by_key_value(data.image_sizes, 'used', true), wpoptimize.no_registered_image_sizes);
				show_sizes_list(unused_image_sizes_container, get_array_items_by_key_value(data.image_sizes, 'used', false), wpoptimize.no_used_image_sizes);
			});

			disable_image_optimization_controls(false);
			update_remove_selected_button_state();
			loaders.hide();

			alert(resp.result.meta.removed_message);
		})
			.fail(function() {
				disable_image_optimization_controls(false);
				update_remove_selected_button_state();
				loaders.hide();

				alert(wpoptimize.error_unexpected_response);
			});
	}

	/**
	 * Changes Remove selected button state on sizes checkbox change.
	 *
	 * @return void
	 */
	function update_remove_selected_button_state() {
		var registered_image_sizes_container = $('#registered_image_sizes'),
			unused_image_sizes_container = $('#unused_image_sizes');

		if ($('input[type="checkbox"]:checked', registered_image_sizes_container).length + $('input[type="checkbox"]:checked', unused_image_sizes_container).length > 0) {
			remove_selected_sizes_btn.prop('disabled', false);
		} else {
			remove_selected_sizes_btn.prop('disabled', true);
		}
	}

	/**
	 * Returns currently selected site.
	 *
	 * @return {number}
	 */
	function get_selected_site() {
		if (sites_select.length && sites_select.val()) {
			return sites_select.val();
		}

		return 1;
	}

	/**
	 * Save Lazy Load settings.
	 *
	 * @return void
	 */
	function save_lazy_load_settings(callback) {
		var form_data = '';

		form_data = $("#wpo_lazy_load_settings input[type='text'], #wpo_lazy_load_settings input[type='radio']").serialize();

		$.each($("#wpo_lazy_load_settings input[type='checkbox']"), function() {
			// Attach matched element names to the form_data with chosen value.
			var empty_val = $(this).prop('checked') ? '1' : '0';
			form_data += '&' + $(this).attr('name') + '=' + empty_val;
		});

		send_command('save_lazy_load_settings', form_data, function(response) {

			$('body').trigger('wpo_purge_cache');

			if (callback) {
				callback(response);
			}
		});
	}

	/**
	 * Handle save lazy load settings.
	 */
	$('#wpo_lazy_load_settings').on('click', '.wp-optimize-settings-save', function() {
		var btn = $(this),
			spinner = btn.next('.wpo_spinner'),
			success_icon  = spinner.next('.dashicons-yes');

		spinner.show();

		save_lazy_load_settings(function() {
			spinner.hide();
			success_icon
				.removeClass('display-none')
				.show()
				.delay(5000)
				.fadeOut('fast', function() {
					success_icon.addClass('display-none');
				});
		});
	});
	
	// append popup container to page body.
	$('body').append('<div id="wpo-popup-preview"></div>');

	/**
	 * Update data-remove_all_transients value for transients preview links.
	 */
	$('#wp-optimize-nav-tab-WP-Optimize-optimize-contents').on('click', '#remove_all_transients', function() {
		var container = $(this).closest('td'),
			value = $(this).is(':checked');
		$('a', container).each(function() {
			$(this).data('remove_all_transients', value);
		});
	});

	/**
	 * Handle click on preview link and run open dialog with preview optimization data for remove.
	 */
	$('#wp-optimize-nav-tab-WP-Optimize-optimize-contents').on('click', '.wpo-optimization-preview', function() {
		open_preview_dialog($(this).data());
		return false;
	});

	/**
	 * Handle change event for "select all" checkbox.
	 */
	$('#wpo-popup-preview').on('change', '#wpo-select-all-preview-rows', function() {
		var table = $(this).closest('table'),
			checked = $(this).prop('checked');

		$('input:checkbox', table).each(function() {
			if (!$(this).is('#wpo-select-all-preview-rows')) {
				$(this).prop('checked', checked);
			}
		});
	});

	/**
	 * Opens dialogs with optimization data for preview and remove.
	 *
	 * @param {object} data {id: <optimization_id, title: <optimization_title>, ...}
	 *
	 * @return {void}
	 */
	function open_preview_dialog(data) {
		var optimization_id = data.id,
			title = data.title,
			dialog = $('#wpo-popup-preview'),
			// table template with pager.
			dialog_html = [
				'<table id="wpo-preview-tablesorter" cellspacing="2" cellpadding="2" class="tablesorter"></table>',
				'<h4 id="wpo-preview-message" style="display: none;"></h4>'
			].join(''),
			pager_html = [
				'<div id="pager" class="pager" style="display: none">',
				'<span class="first dashicons dashicons-controls-skipback"></span>',
				'<span class="prev dashicons dashicons-controls-back"></span>',

				'<input type="text" class="pagedisplay">',
				'<span class="pagedisplay-count"></span>',

				'<span class="next dashicons dashicons-controls-forward"></span>',
				'<span class="last dashicons dashicons-controls-skipforward"></span>',

				'<select class="pagesize">',
				'<option value="50">50</option>',
				'<option value="100">100</option>',
				'<option value="200">200</option>',
				'<option value="300">300</option>',
				'<option value="400">400</option>',
				'<option value="500">500</option>',
				'</select>',
				'</div>'
			].join(''),
			sites_select_html = '',
			sites_select_options = [],
			dialog_buttons = {};

		// build sites select html.
		if ('undefined' != typeof wpoptimize.sites && wpoptimize.sites.length) {
			for (var i in wpoptimize.sites) {
				if (!wpoptimize.sites.hasOwnProperty(i)) continue;

				sites_select_options.push(['<option value="', wpoptimize.sites[i].blog_id, '">', wpoptimize.sites[i].domain, wpoptimize.sites[i].path, '</option>'].join(''));
			}
			sites_select_html = [
				'<select id="wpo-preview-site" style="display: none">',
				sites_select_options.join(''),
				'</select>'
			].join('');
		}

		// add delete button to the dialog.
		dialog_buttons[wpoptimize.delete_selected_items_btn] = function() {
			var selected_ids = [],
				table = $('#wpo-preview-tablesorter');
		
			$('input:checkbox:checked', table).each(function() {
				if (!$(this).is('#wpo-select-all-preview-rows')) {
					selected_ids.push($(this).val());
				}
			});

			// @codingStandardsIgnoreLine
			if (0 == selected_ids.length) return;

			var optimization_data = data;
			optimization_data['ids'] = selected_ids;

			// set site_id option for multisite.
			if ($('#wpo-preview-site').length) {
				optimization_data['site_id'] = $('#wpo-preview-site').val();
			}

			preview_loader.show();

			wp_optimize.send_command('do_optimization',
				{
					'optimization_id': optimization_id,
					'data': optimization_data
				},
				function (response) {
					// force reload table content.
					$('#wpo-preview-tablesorter')[0].dispatchEvent(new CustomEvent("reload", {}));
					// uncheck all checkboxes in table.
					$('#wpo-select-all-preview-rows').prop('checked', false);

					send_command('get_optimization_info', {optimization_id: optimization_id}, function(resp) {
						var meta = (resp && resp.result && resp.result.meta) ? resp.result.meta : {},
							message = (resp && resp.result && resp.result.output) ? resp.result.output.join('<br>') : '',
							checkboxes = {};

						if ('' != message) {
							// save checkbox states before update optimization info text.
							// used in additional options, like for "remove all transients"
							$(['#optimization_info_', optimization_id, ' input[type="checkbox"]'].join('')).each(function() {
								checkboxes[$(this).attr('name')] = $(this).prop('checked');
							});

							$(['#optimization_info_', optimization_id].join('')).html(message);

							// restore saved checkboxes state.
							for (var i in checkboxes) {
								if (!checkboxes.hasOwnProperty(i)) continue;
								$(['#optimization_info_', optimization_id, ' input[name="',i,'"]'].join('')).prop('checked', checkboxes[i]);
							}
						}
					});
				}
			);
		};

		// add cancel button to the dialog.
		dialog_buttons[wpoptimize.close_btn] = function() {
			$(this).dialog('destroy');
		};

		// open dialog.
		dialog.dialog({
			autoOpen: false,
			title: title,
			minWidth: 800,
			modal: true,
			open: function() {
				$(this).dialog("option", "minHeight", 300); // Explicitly set minHeight
			},
			close: function() {
				// destroy dialog on close.
				$(this).dialog('destroy');
				// clear popup content.
				$('#wpo-popup-preview').html('');
			},
			buttons: dialog_buttons
		});

		// hide table before loading.
		$('#wpo-preview-tablesorter').hide();

		// put table template into dialog.
		dialog.html(dialog_html);

		// hide delete button.
		$('.ui-dialog-buttonpane button').first().hide();

		// add pager and site selector to dialog.
		$('.ui-dialog-buttonpane').prepend([pager_html, sites_select_html].join(''));

		$("#pager").show();

		// add spinner to title.
		$('.ui-dialog-title').append(['<i id="wpo-preview-loader"><img width="12" height="12" src="',wpoptimize.spinner_src,'" /></i>'].join(''));

		var preview_loader = $('#wpo-preview-loader > img'),
			preview_site_select = $('#wpo-preview-site');

		/**
		 * Create new data source object used for fetch preview data from optimization.
		 *
		 * @type {TableSorter_DataSource}
		 */
		var ds = new WPO_Table_DataSource({
			optimization_id: optimization_id,
			limit: 1
		});

		for (var i in data) {
			if ('id' == i || 'title' == i) continue;
			ds.set_option(i, data[i]);
		}

		// if multisite the add site id value to data source object.
		if (preview_site_select.length && preview_site_select.val()) {
			ds.set_option('site_id', preview_site_select.val());
		}

		// handle change event for change site select.
		preview_site_select.on('change', function() {
			// update site id option.
			ds.set_option('site_id', preview_site_select.val());
			// force reload table content.
			$('#wpo-preview-tablesorter').trigger('reload');
		});

		/**
		 * Get data from optimization for preview and show it in dialog.
		 */
		ds.fetch().done(
			function(response) {
				var table = $('#wpo-preview-tablesorter');

				try {
					response = wpo_parse_json(response);
				} catch (e) {
					alert(wpoptimize.error_unexpected_response);
					return;
				}

				// hide table and pager until data loading.
				table.hide();

				// add table headings with received from optimization
				var i,header = [], footer = [],
					j = 1, // no sorters counter, 0 index already filled for column with checkboxes.
					no_sorters = { 0 : { sorter: false } };

				// build header and footer for preview table.
				header.push('<th style="width: 20px"><input id="wpo-select-all-preview-rows" type="checkbox" /></th>');
				footer.push('<th></th>');

				for (i in response.result.columns) {
					if (!response.result.columns.hasOwnProperty(i)) continue;

					// set as no sortable option.
					no_sorters[j] = { sorter: false };
					j++;

					header.push(['<th class="header">', response.result.columns[i],'</th>'].join(''));
					footer.push(['<th>',response.result.columns[i],'</th>'].join(''));
				}

				table.append(['<thead><tr>',header.join(''),'</tr></thead>'].join(''));
				table.append(['<tfoot><tr>',footer.join(''),'</tr></tfoot>'].join(''));
				table.append('<tbody></tbody>');

				// initialize table sorter for displayed data.
				const tableEl = table[0];

				const table_pager = new WPO_TablePager({
					table: tableEl,
					container: document.getElementById('pager'),
					dataSource: ds
				});

				table_pager.loadTableData();

				// handle reload event, used when elements are deleting.
				tableEl.addEventListener('reload', function() {
					table_pager.loadTableData();
				});

				// handle loading start for preview.
				tableEl.addEventListener('load_start', function() {
					preview_loader.show();
				});

				// handle loading end data for preview.
				tableEl.addEventListener('load_end', function(e) {
					var response = e.detail.response;
					preview_loader.hide();

					if (parseInt(response.result.total) > 0) {
						// show table with found items.
						$('#wpo-preview-tablesorter').show();
						// hide "no items found" message.
						$('#wpo-preview-message').hide();
						// show pager.
						$('.ui-dialog-buttonpane #pager').show();
						// show delete button.
						$('.ui-dialog-buttonpane button').first().show();

						dialog.dialog("option", "height", 300);

					} else {
						// hide the table.
						$('#wpo-preview-tablesorter').hide();
						// show "no items found" message.
						$('#wpo-preview-message').text(response.result.message).show();
						// hide pager.
						$('.ui-dialog-buttonpane #pager').hide();
						// hide delete button.
						$('.ui-dialog-buttonpane button').first().hide();
					}
					// show site select for multisite.
					$('#wpo-preview-site').show();

				});
			}
		);

		// open the dialog.
		dialog.dialog('open');
	}

	/**
	 * Update data-remove_all_transients value for transients preview links.
	 */
	$('#remove_all_transients').on('change', function() {
		var container = $(this).closest('td'),
			value = $(this).is(':checked');

		$('a', container).each(function() {
			$(this).data('remove_all_transients', value);
		});
	});

	/**
	 * Always purge this page functionality.
	 */
	var wpo_always_purge_table = $('#wpo_always_purge_table'),
		wpo_always_purge_post_types_select = $('#wpo_always_purge_post_types_select'),
		wpo_always_purge_post_id_select = $('#wpo_always_purge_post_id_select');

	 /**
	  * Add page for purge.
	  */
	$('#wpo_add_always_purge_btn').on('click', function() {
		var btn = $(this),
			row = btn.closest('tr'),
			post_type_select = $('#wpo_always_purge_post_types_select', row),
			post_type = post_type_select.val(),
			post_select = $('#wpo_always_purge_post_id_select', row),
			post_id = post_select.val(),
			post_title = $(['option[value="',post_id,'"]'].join('')).text(),
			validation = true;

			var selected_post_types = [];
			$('#wpo_always_purge_post_types_select', row).find(':selected').each(function() {
				selected_post_types.push($(this).text());
			});

		var new_row_html = [
			'<tr><td><input type="hidden" class="cache-settings-array" name="always_purge_post_type" value="',post_type.join(','),'">',selected_post_types.join(', '),'</td><td><input type="hidden" class="cache-settings-array" name="always_purge_post_id" value="',post_id,'">',post_title,'</td><td><a class="wpo-always-purge-delete wpo-delete" href="javascript: ;">',wpoptimize.delete,'</a></td></tr>'
		].join('');

		// check if selected post type
		if (0 == post_type.length) {
			validation = false;
			$('.select2-selection', post_type_select.next()).addClass('wpo_error_field');
		}
	
		// check if selected post
		if (!post_id) {
			validation = false;
			$('.select2-selection', post_select.next()).addClass('wpo_error_field');
		}

		if (validation) {
			// remove red borders
			$('.select2-selection', post_type_select.next()).removeClass('wpo_error_field');
			$('.select2-selection', post_select.next()).removeClass('wpo_error_field');
			// clear selected values.
			post_type_select.val(null).trigger('change');
			post_select.val(null).trigger('change');
			// add row with new settings.
			row.before(new_row_html);
		}
	});

	 /**
	  * Delete page for purge.
	  */
	wpo_always_purge_table.on('click', '.wpo-always-purge-delete', function() {
		var btn = $(this),
			row = btn.closest('tr');

		row.remove();
	});

	wpo_always_purge_post_types_select.select2();

	wpo_always_purge_post_id_select.select2({
		ajax: {
			url: ajaxurl,
			type: 'post',
			dataType: 'json',
			data: function(params) {

			  var query = {
				action: 'wp_optimize_ajax',
				subaction: 'get_posts_list',
				nonce: wp_optimize_send_command_data.nonce,
				data: {
					search: params.term,
					page: params.page || 1
				}
			  }
		
			  return query;
			}
		}
	});


	/**
	 * User per role cache staff.
	 */
	var enable_per_role_cache_checkbox = $('#enable_per_role_cache'),
		per_role_cache_roles_list = $('#wpo_per_role_cache_roles_list');

	enable_per_role_cache_checkbox.on('change', function() {
		if (enable_per_role_cache_checkbox.prop('checked')) {
			per_role_cache_roles_list.removeClass('wpo_hidden');
		} else {
			per_role_cache_roles_list.addClass('wpo_hidden');
		}
	});

	/**
	 * Save DB analysis options.
	 *
	 * @param {function} callback Next function after successful save
	 * @return void
	 */
	 function save_table_analysis_options(callback) {
		var options = {};
		options['is_enabled'] = $('#enable-db-analysis').is(":checked");

		WP_Optimize.send_command('save_table_analysis_options', options, function(resp) {
			if (resp.message) {
				table_analysis_show_response_message(resp.message);
				callback();
			}
		});
	}

	/**
	 * Hide the operation result message after 3 seconds
	 */
	function table_analysis_hide_response_message() {
		setTimeout(function() {
			$("#wpo-save-options-response").html('');
			$("#wpo-save-options-response").hide();
		}, 3000);
	}

	/**
	 * Show the response received
	 *
	 * @param {string} msg Response from backend
	 */
	function table_analysis_show_response_message(msg) {
		$("#wpo-save-options-response").show();
		$("#wpo-save-options-response").html(msg);

		table_analysis_hide_response_message();
	}

	/**
	 * Reload tab contents via AJAX
	 */
	function reload_table_analysis_report() {
		$("#wpo_loading_spinner span, #wpo_loading_spinner img").removeClass('hidden').show();
		
		if (is_table_analysis_enabled_and_loading() && !$('div.blockUI').is(':visible')) {
			wp_optimize.block_ui(wpoptimize.no_information_available_yet + ' ' +  wpoptimize.please_wait_a_few_seconds_while_we_refresh, {}, 0, false);
		}
		
		WP_Optimize.send_command('get_table_analysis_data', {"selected-plugin": $("#wpo-plugin-usage-select").val()}, function(resp) {
			$("#wpo_loading_spinner span, #wpo_loading_spinner img").addClass('hidden').hide();

			$('#wpo-table-analysis-report-container').html(resp.html);
			
			table_analysis_add_report_event_listeners();

			// If the data is still not available then we re-run the request.
			if (is_table_analysis_enabled_and_loading()) {
				setTimeout(reload_table_analysis_report, 5000);
			} else {
				$.unblockUI();
			}

		});
	}

	/**
	 * Attach to settings elements events
	 */
	function table_analysis_add_settings_event_listeners() {
		$('#wpo-wipe-table-usage-data').on("click", function(evt) {
			evt.preventDefault();

			$('#wpo-save-options-response').html(wpoptimize.please_wait);

			WP_Optimize.send_command('wipe_table_analysis_data', {}, function(resp) {
				table_analysis_show_response_message(resp.message);

				reload_table_analysis_report();
			});
		});

		$('#enable-db-analysis').on("change", function() {
			save_table_analysis_options(reload_table_analysis_report);
		});
	}

	/**
	 * Verifies whether table analysis is enabled and data still not loaded.
	 *
	 * @returns bool
	 */
	function is_table_analysis_enabled_and_loading() {
		var is_enabled = $('#enable-db-analysis').prop('checked'),
			is_plugin_select_visible = $('#wpo-plugin-usage-select').is(':visible');
		
		return is_enabled && !is_plugin_select_visible;
	}

	/**
	 * Attach to report elements events
	 */
	function table_analysis_add_report_event_listeners() {
		$('#wpo-plugin-usage-select').on("change", function() {
			$('.wpo-plugin-tables-usage').hide();
			$('#wpo-plugin-tables-usage-' + this.value).show();

			if ('' != this.value) {
				$('#wpo-db-analysis-table-search, #wpo-table-analysis-reload').removeClass('hidden');
			} else {
				$('#wpo-db-analysis-table-search, #wpo-table-analysis-reload').addClass('hidden');
			}
		});

		$('#wpo-db-analysis-table-search').on('keyup', function() {
			var search_string = this.value;

			$('.wpo-plugin-tables-usage #the-list tr').each(function() {
				var the_row = this;
				$(this).children('td:nth-child(2)').each(function() {
					if (this.innerHTML.indexOf(search_string) > -1) {
						$(the_row).show();
					} else {
						$(the_row).hide();
					}
				});
			});
		});
		
		$('#wpo-db-analysis-table-search').on('keypress', function(event) {
			if (13 === event.keyCode) {
				event.preventDefault();
			}
		});

		$("#wpo-table-analysis-reload").on("click", reload_table_analysis_report);
	}

	table_analysis_add_settings_event_listeners();
	table_analysis_add_report_event_listeners();

	/**
	 * Saves images dimensions
	 *
	 * @param {string} button_clicked which button click triggered the save event (save or toggle)
	 */
	function save_images_dimensions_settings(button_clicked) {
		var spinner = images_dimensions_save_settings_btn.next('.wpo_spinner'),
			success_icon = spinner.next('.dashicons-yes');

		spinner.show();
		block_ui(wpoptimize.saving);

		var data = {
			"images_dimensions": images_dimensions_btn.is(":checked"),
			"ignore_classes": images_dimensions_ignore_classes.val()
		};

		send_command('save_images_dimension_option', data, function(response) {
			spinner.hide();
			$.unblockUI();
			if (response.success) {
				if ('save_button' === button_clicked) {
					success_icon.fadeIn('fast').fadeOut('slow');
				}
			}
		});
	}

	images_dimensions_btn.on('click', function() {
		images_dimensions_hidden_content.css('display', images_dimensions_btn.is(":checked") ? 'block' : 'none');
		save_images_dimensions_settings('toggle_button');
	});

	images_dimensions_save_settings_btn.on('click', function() {
		save_images_dimensions_settings('save_button');
	});

	// Export reload function for WP_Optimize_Premium()
	return {
		reload_table_analysis_report: reload_table_analysis_report
	}

};

/**
 * Flexible scheduler staff.
 */
jQuery(function($) {

	var $auto_options = $('#wp-optimize-auto-options');
	var $db_settings_form = $('#database_settings_form');
	var $time_fields = $('input[type="time"]');
	var $date_fields = $('input[type="date"]');
	var today = new Date().toISOString().split('T')[0];

	// This helps to keep track of scheduled events
	var count = $('.wpo_auto_event:last').data('count') || 0;

	// Use time picker when input[type="time"] not supported
	$time_fields.each(function(index, element) {
		if (!Modernizr.inputtypes.time) {
			$(element).timepicker({'timeFormat': 'H:i'});
			$(element).addClass('no_date_time_support');
			$(element).on('changeTime', function() {
				$(this).timepicker('hide');
			});
		}
	});

	$auto_options.on('focus', 'input[type="time"]', function() {
		var element = $(this).get(0);
		if (!Modernizr.inputtypes.time) {
			$(element).timepicker({'timeFormat': 'H:i'});
			$(element).on('changeTime', function() {
				$(this).timepicker('hide');
			});
		}
	});

	$auto_options.on('keypress', 'input', function(e) {
		if (13 === e.keyCode) return false;
	});

	// Use datepicker when input[type="date"] not supported
	$date_fields.each(function(index, element) {
		if (!Modernizr.inputtypes.date) {
			$(element).datepicker({
				dateFormat: "yy-mm-dd",
				minDate: 0
			});
			$(element).addClass('no_date_time_support');
		}
	});

	$auto_options.on('focus', 'input[type="date"]', function() {
		var ele = $(this).get(0);
		if (!Modernizr.inputtypes.date) {
			$(ele).datepicker({
				dateFormat: "yy-mm-dd",
				minDate: 0
			});
		}
	});

	if (0 !== $('.wpo_scheduled_event').length) {
		$('.wpo_no_schedules').hide();
	} else {
		$('.wpo_no_schedules').show();
	}

	$('.wpo_auto_optimizations').select2({
		placeholder: wpoptimize.select_optimizations
	});

	$('.wpo_auto_optimizations').on('select2:opening select2:closing', function(event) {
		var $searchfield = $(this).parent().find('.select2-search__field');
		$searchfield.prop('disabled', true);
	});

	$('#purge_cache_permissions').select2({
		placeholder: wpoptimize.select_roles
	});

	/**
	 * Detect change on schedule panel and set reminder
	 */
	$auto_options.on('change', 'select, input[type="date"], input[type="time"]', function() {
		$("#save_settings_reminder").slideDown();
		display_headers();
	});

	/**
	 * Adds settings fields for event scheduling
	 */
	$db_settings_form.on('click', '#wpo-add-event', function(e) {
		e.preventDefault();
		count++;
		var optimizations = WP_Optimize_Handlebars.optimizations.handlebars({'optimizations': wpoptimize.auto_optimizations, 'count': count});
		var schedule_types = WP_Optimize_Handlebars.schedule_types.handlebars({'schedule_types': wpoptimize.schedule_types, 'count': count});
		var add_schedule_new 	= wpoptimize.add_schedule_new;
		var add_schedule_cancel = wpoptimize.add_schedule_cancel;
		var action = WP_Optimize_Handlebars.action.handlebars({'count': count, 'add_schedule_new': add_schedule_new, 'add_schedule_cancel': add_schedule_cancel });
		var html_content = '<div class="wpo_auto_event wpo_cf" data-count="' + count +'">';
		html_content += optimizations + schedule_types + action;
		html_content += '</div>';
		$('#wpo_auto_events').append(html_content);
		$('.wpo_auto_optimizations').select2({
			placeholder: wpoptimize.select_optimizations
		});
		$('.wpo_auto_optimizations').on('select2:opening select2:closing', function(event) {
			var $searchfield = $(this).parent().find('.select2-search__field');
			$searchfield.prop('disabled', true);
		});
	});

	/**
	 * Show appropriate fields (date, time, week and day) when schedule type is changed
	 */
	$db_settings_form.on('change', '.wpo_schedule_type', function() {
		var $container = $(this).closest('.wpo_auto_event');

		var add_schedule_new 	= wpoptimize.add_schedule_new;
		var add_schedule_cancel = wpoptimize.add_schedule_cancel;

		// Use existing count, if it is editing to existing event or use incremented count
		var event_count = $container.data('count') || count;
		var schedule_type = $(this).val();
		var class_name = '';
		if (!Modernizr.inputtypes.date || !Modernizr.inputtypes.time) {
			class_name = 'no_date_time_support';
		}
		var today = new Date();
		var dateValue = formatDate(today);
		var field_details = {
			'date': wpoptimize.date,
			'time': wpoptimize.time,
			'day': wpoptimize.day,
			'day_number': wpoptimize.day_number,
			'days': wpoptimize.days,
			'date_value': dateValue,
			'time_value': '00:00',
			'status': wpoptimize.active,
			'status_value': "checked",
			'week_days': wpoptimize.week_days,
			'week': wpoptimize.week,
			'count': event_count,
			'class_name': class_name,
			'today': today
		};
		var schedule_fields = display_field_details(schedule_type, field_details);
		var status = WP_Optimize_Handlebars.status.handlebars({'details': field_details});
		var action = WP_Optimize_Handlebars.action.handlebars({'add_schedule_new': add_schedule_new, 'add_schedule_cancel': add_schedule_cancel});
		$(this).next().html('');
		$container.find('.wpo_event_status').remove();
		$container.find('.wpo_event_actions').remove();
		if ('' !== schedule_fields) {
			$(this).next().html(schedule_fields);
		}
		$container.append(status + action);
	});

	/**
	 * Edit event details
	 */
	$db_settings_form.on('click', '#wp-optimize-auto-options .wpo_edit_event', function() {
		var $container = $(this).closest('.wpo_scheduled_event');
		$container.hide();
		$container.next().show();
		display_headers();
		display_select2_options_after_document_change();
	});

	/**
	 * Remove event details
	 */
	$db_settings_form.on('click', '.wpo_remove_event', function() {
		var count = $(this).data('count');
		var ok_remove = confirm(wpoptimize.confirm_remove_task);
		if (true === ok_remove) {
			var $scheduled_event = $(this).closest('.wpo_scheduled_event');
			var $auto_event = $(this).closest('.wpo_auto_event');

			// If event deleted from list, then remove form as well
			if (count == $scheduled_event.next().data('count')) {
				$scheduled_event.next().remove();
				$scheduled_event.remove();
			}

			// If event deleted from form, then remove stored details as well
			if (count == $auto_event.prev().data('count')) {
				$auto_event.prev().remove();
			}

			// Delete newly created event
			$auto_event.remove();

			setTimeout(function(){
				$('#wp-optimize-save-database-settings').trigger('click');
			}, 500);

			//$("#save_settings_reminder").slideDown();
			display_headers();
		}
	});

	/**
	 * Cancel event edit.
	 */
	$db_settings_form.on('click', '#wp-optimize-auto-options .wpo_cancel_event', function() {
		var $container = $(this).closest('.wpo_auto_event');
		$container.hide();
		$container.prev().show();
	});

	/**
	 * Additional UI processing for save settings in premium
	 */
	$('#database_settings_form').on('wpo-saving-form-data', function(e) {
		var all_filled = true;
		var $form = $('#database_settings_form');
		$form.find('.wpo_auto_optimizations').each(function() {
			var optimizations = $(this).val();
			if (Array.isArray(optimizations) && 0 === optimizations.length) {
				all_filled = false;
			}
		});

		$form.find('.wpo_schedule_type').each(function() {
			if (!$(this).val()) {
				all_filled = false;
			}
		});

		$form.find('.wpo_schedule_fields input').each(function() {
			var value = $(this).val();
			var validate = $(this)[0].type;
			switch (validate) {
				case 'date':
					var params = value.split('-');
					var date = parseInt(params[2]),
						month = parseInt(params[1]) - 1,
						year = parseInt(params[0]),
						dateObj = new Date(year, month, date);
					if (dateObj instanceof Date && isNaN(dateObj)) {
						all_filled = false;
					}
					break;
	
				case 'time':
					var regex = /^([0-1]?[0-9]|2[0-4]):([0-5][0-9])(:[0-5][0-9])?$/;
					if (!regex.test(value)) {
						all_filled = false;
					}
					break;
			}
		});

		if (false === all_filled) {
			$form.form_errors.add('missing-fields', '');
			e.stopImmediatePropagation();
			$form.find('.wp-optimize-settings-save-results')
				.show()
				.addClass('wpo_alert_notice')
				.text(wpoptimize.fill_all_fields)
				.delay(5000)
				.fadeOut(3000, function() {
					$(this).removeClass('wpo_alert_notice');
				});
		} else {
			$form.form_errors.remove('missing-fields');
		}

		$("#save_settings_reminder").slideUp('normal', function() {
			display_headers();
		});

	});

	/**
	 * Displays field details based on selected scheduled type
	 *
	 * @param {string} schedule_type
	 * @param {object} field_details
	 *
	 * @return {string}
	 */
	function display_field_details(schedule_type, field_details) {
		var schedule_fields = '';
		switch (schedule_type) {
			case 'wpo_once':
				schedule_fields = WP_Optimize_Handlebars.once.handlebars({'details': field_details});
				break;
			case 'wpo_daily':
				schedule_fields = WP_Optimize_Handlebars.daily.handlebars({'details': field_details});
				break;
			case 'wpo_weekly':
				schedule_fields = WP_Optimize_Handlebars.weekly.handlebars({'details': field_details});
				break;
			case 'wpo_fortnightly':
				schedule_fields = WP_Optimize_Handlebars.fortnightly.handlebars({'details': field_details});
				break;
			case 'wpo_monthly':
				schedule_fields = WP_Optimize_Handlebars.monthly.handlebars({'details': field_details});
				break;
		}
		return schedule_fields;
	}


	/**
	 * Displays select2 options after document change.
	 *
	 * @return void
	 */
	function display_select2_options_after_document_change() {
		$('.wpo_auto_optimizations').select2({
			placeholder: wpoptimize.select_optimizations
		});

		$('.wpo_auto_optimizations').on('select2:opening select2:closing', function(event) {
			var $searchfield = $(this).parent().find('.select2-search__field');
			$searchfield.prop('disabled', true);
		});
	}

	/**
	 * Displays scheduled event headers
	 *
	 * @return void
	 */
	function display_headers() {
		if (0 === $('.wpo_scheduled_event:visible').length) {
			$('.wpo_auto_event_heading_container').hide();
			$('.wpo_no_schedules').show();
		} else {
			$('.wpo_auto_event_heading_container').show();
			$('.wpo_no_schedules').hide();
		}

		if (0 === $('.wpo_scheduled_event:visible').length && 0 === $('.wpo_auto_event:visible').length && !$('#save_settings_reminder').is(':visible')) {
			$('.wpo_no_schedules').show();
		} else {
			$('.wpo_no_schedules').hide();
		}
	}

	/**
	 * Converts date object to user friendly date string
	 *
	 * @param {Date} date - Date object to be converted
	 *
	 * @return String - in the format YYYY-MM-DD (e.g. 2022-12-28)
	 */
	function formatDate(date) {
			month = '' + (date.getMonth() + 1),
			day = '' + date.getDate(),
			year = date.getFullYear();
	
		if (month.length < 2) month = '0' + month;
		if (day.length < 2) day = '0' + day;
	
		return [year, month, day].join('-');
	}

	// On check/uncheck of Enable minification of CSS files display the unused css removal one
	$("#enable_css_minification").on('click', function() {
		var enable_unused_css_wrapper = $('#enable_unused_css_removal_wrapper');
		var is_enabled = $(this).prop('checked');
		if (is_enabled) {
			enable_unused_css_wrapper.show();
		} else {
			enable_unused_css_wrapper.hide();
			$('#enable_unused_css').prop('checked', false);
		}
	});
});
