Select.js

import UI5Element from "@ui5/webcomponents-base/dist/UI5Element.js";
import litRender from "@ui5/webcomponents-base/dist/renderer/LitRenderer.js";
import {
	isSpace,
	isUp,
	isDown,
	isEnter,
	isEscape,
	isShow,
	isTabNext,
	isTabPrevious,
} from "@ui5/webcomponents-base/dist/Keys.js";
import Integer from "@ui5/webcomponents-base/dist/types/Integer.js";
import { getFeature } from "@ui5/webcomponents-base/dist/FeaturesRegistry.js";
import { getEffectiveAriaLabelText } from "@ui5/webcomponents-base/dist/util/AriaLabelHelper.js";
import ValueState from "@ui5/webcomponents-base/dist/types/ValueState.js";
import "@ui5/webcomponents-icons/dist/slim-arrow-down.js";
import { isPhone } from "@ui5/webcomponents-base/dist/Device.js";
import { getI18nBundle } from "@ui5/webcomponents-base/dist/i18nBundle.js";
import "@ui5/webcomponents-icons/dist/decline.js";
import {
	VALUE_STATE_SUCCESS,
	VALUE_STATE_INFORMATION,
	VALUE_STATE_ERROR,
	VALUE_STATE_WARNING,
	INPUT_SUGGESTIONS_TITLE,
} from "./generated/i18n/i18n-defaults.js";
import Option from "./Option.js";
import Label from "./Label.js";
import ResponsivePopover from "./ResponsivePopover.js";
import Popover from "./Popover.js";
import List from "./List.js";
import StandardListItem from "./StandardListItem.js";
import Icon from "./Icon.js";
import Button from "./Button.js";

// Templates
import SelectTemplate from "./generated/templates/SelectTemplate.lit.js";
import SelectPopoverTemplate from "./generated/templates/SelectPopoverTemplate.lit.js";

// Styles
import selectCss from "./generated/themes/Select.css.js";
import ResponsivePopoverCommonCss from "./generated/themes/ResponsivePopoverCommon.css.js";
import ValueStateMessageCss from "./generated/themes/ValueStateMessage.css.js";
import SelectPopoverCss from "./generated/themes/SelectPopover.css.js";

/**
 * @public
 */
const metadata = {
	tag: "ui5-select",
	languageAware: true,
	managedSlots: true,
	slots: /** @lends sap.ui.webcomponents.main.Select.prototype */ {

		/**
		 * Defines the <code>ui5-select</code> options.
		 *
		 * <br><br>
		 * <b>Note:</b> Only one selected option is allowed.
		 * If more than one option is defined as selected, the last one would be considered as the selected one.
		 *
		 * <br><br>
		 * <b>Note:</b> Use the <code>ui5-option</code> component to define the desired options.
		 * @type {HTMLElement[]}
		 * @slot
		 * @public
		 */
		"default": {
			propertyName: "options",
			type: HTMLElement,
			listenFor: { include: ["*"] },
		},

		/**
		 * Defines the value state message that will be displayed as pop up under the <code>ui5-select</code>.
		 * <br><br>
		 *
		 * <b>Note:</b> If not specified, a default text (in the respective language) will be displayed.
		 * <br>
		 * <b>Note:</b> The <code>valueStateMessage</code> would be displayed,
		 * when the <code>ui5-select</code> is in <code>Information</code>, <code>Warning</code> or <code>Error</code> value state.
		 * @type {HTMLElement[]}
		 * @since 1.0.0-rc.9
		 * @slot
		 * @public
		 */
		valueStateMessage: {
			type: HTMLElement,
		},
	},
	properties: /** @lends  sap.ui.webcomponents.main.Select.prototype */  {

		/**
		 * Defines whether <code>ui5-select</code> is in disabled state.
		 * <br><br>
		 * <b>Note:</b> A disabled <code>ui5-select</code> is noninteractive.
		 *
		 * @type {boolean}
		 * @defaultvalue false
		 * @public
		 */
		disabled: {
			type: Boolean,
		},

		/**
		 * Determines the name with which the <code>ui5-select</code> will be submitted in an HTML form.
		 * The value of the <code>ui5-select</code> will be the value of the currently selected <code>ui5-option</code>.
		 *
		 * <br><br>
		 * <b>Important:</b> For the <code>name</code> property to have effect, you must add the following import to your project:
		 * <code>import "@ui5/webcomponents/dist/features/InputElementsFormSupport.js";</code>
		 *
		 * <br><br>
		 * <b>Note:</b> When set, a native <code>input</code> HTML element
		 * will be created inside the <code>ui5-select</code> so that it can be submitted as
		 * part of an HTML form. Do not use this property unless you need to submit a form.
		 *
		 * @type {string}
		 * @defaultvalue ""
		 * @public
		 */
		name: {
			type: String,
		},

		/**
		 * Defines the value state of the <code>ui5-select</code>.
		 * <br><br>
		 * Available options are:
		 * <ul>
		 * <li><code>None</code></li>
		 * <li><code>Error</code></li>
		 * <li><code>Warning</code></li>
		 * <li><code>Success</code></li>
		 * <li><code>Information</code></li>
		 * </ul>
		 *
		 * @type {ValueState}
		 * @defaultvalue "None"
		 * @public
		 */
		valueState: {
			type: ValueState,
			defaultValue: ValueState.None,
		},

		/**
		 * Defines whether the <code>ui5-select</code> is required.
		 *
		 * @since 1.0.0-rc.9
		 * @type {Boolean}
		 * @defaultvalue false
		 * @public
		 */
		required: {
			type: Boolean,
		},

		/**
		 * Defines the aria-label attribute for the select.
		 *
		 * @type {String}
		 * @since 1.0.0-rc.9
		 * @private
		 * @defaultvalue ""
		 */
		ariaLabel: {
			type: String,
		},

		/**
		 * Receives id(or many ids) of the elements that label the select.
		 *
		 * @type {String}
		 * @defaultvalue ""
		 * @private
		 * @since 1.0.0-rc.9
		 */
		ariaLabelledby: {
			type: String,
			defaultValue: "",
		},

		_text: {
			type: String,
			noAttribute: true,
		},

		_iconPressed: {
			type: Boolean,
			noAttribute: true,
		},

		/**
		 * @private
		 */
		opened: {
			type: Boolean,
		},

		_listWidth: {
			type: Integer,
			defaultValue: 0,
			noAttribute: true,
		},

		/**
		 * @private
		 */
		focused: {
			type: Boolean,
		},
	},
	events: /** @lends sap.ui.webcomponents.main.Select.prototype */ {
		/**
		 * Fired when the selected option changes.
		 *
		 * @event
		 * @param {HTMLElement} selectedOption the selected option.
		 * @public
		 */
		change: {
			detail: {
				selectedOption: {},
			},
		},
	},
};

/**
 * @class
 *
 * <h3 class="comment-api-title">Overview</h3>
 * The <code>ui5-select</code> component is used to create a drop-down list.
 * The items inside the <code>ui5-select</code> define the available options by using the <code>ui5-option</code> component.
 *
 * <h3>Keyboard Handling</h3>
 * The <code>ui5-select</code> provides advanced keyboard handling.
 * If the <code>ui5-select</code> is focused,
 * you can open or close the drop-down by pressing <code>F4</code>, <code>ALT+UP</code> or <code>ALT+DOWN</code> keys.
 * Once the drop-down is opened, you can use the <code>UP</code> and <code>DOWN</code> arrow keys
 * to navigate through the available options and select one by pressing the <code>Space</code> or <code>Enter</code> keys.
 * <br>
 * <h3>ES6 Module Import</h3>
 * <code>import "@ui5/webcomponents/dist/Select";</code>
 * <br>
 * <code>import "@ui5/webcomponents/dist/Option";</code>
 * @constructor
 * @author SAP SE
 * @alias sap.ui.webcomponents.main.Select
 * @extends sap.ui.webcomponents.base.UI5Element
 * @tagname ui5-select
 * @appenddocs Option
 * @public
 * @since 0.8.0
 */
class Select extends UI5Element {
	static get metadata() {
		return metadata;
	}

	static get render() {
		return litRender;
	}

	static get template() {
		return SelectTemplate;
	}

	static get staticAreaTemplate() {
		return SelectPopoverTemplate;
	}

	static get styles() {
		return selectCss;
	}

	static get staticAreaStyles() {
		return [ResponsivePopoverCommonCss, ValueStateMessageCss, SelectPopoverCss];
	}

	constructor() {
		super();

		this._syncedOptions = [];
		this._selectedIndex = -1;
		this._selectedIndexBeforeOpen = -1;
		this._escapePressed = false;
		this._lastSelectedOption = null;
		this.i18nBundle = getI18nBundle("@ui5/webcomponents");
	}

	onBeforeRendering() {
		this._syncSelection();
		this._enableFormSupport();
	}

	onAfterRendering() {
		this.toggleValueStatePopover(this.shouldOpenValueStateMessagePopover);

		if (this._isPickerOpen && !this._listWidth) {
			this._listWidth = this.responsivePopover.offsetWidth;
		}
	}

	_onfocusin() {
		this.focused = true;
	}

	_onfocusout() {
		this.focused = false;
		this.itemSelectionAnnounce();
	}

	get _isPickerOpen() {
		return this.responsivePopover && this.responsivePopover.opened;
	}

	async _respPopover() {
		this._iconPressed = true;
		const staticAreaItem = await this.getStaticAreaItemDomRef();
		return staticAreaItem.querySelector("[ui5-responsive-popover]");
	}

	/**
	 * Currently selected option.
	 * @readonly
	 * @type { ui5-option }
	 * @public
	 */
	get selectedOption() {
		return this.options.find(option => option.selected);
	}

	async _toggleRespPopover() {
		this.responsivePopover = await this._respPopover();
		if (this.disabled) {
			return;
		}

		if (this._isPickerOpen) {
			this.responsivePopover.close();
		} else {
			this.responsivePopover.open(this);
		}
	}

	_syncSelection() {
		let lastSelectedOptionIndex = -1;
		const opts = this.options.map((opt, index) => {
			if (opt.selected) {
				lastSelectedOptionIndex = index;
			}

			opt.selected = false;

			return {
				selected: false,
				icon: opt.icon,
				value: opt.value,
				textContent: opt.textContent,
				id: opt._id,
			};
		});

		if (lastSelectedOptionIndex > -1) {
			opts[lastSelectedOptionIndex].selected = true;
			this.options[lastSelectedOptionIndex].selected = true;
			this._text = opts[lastSelectedOptionIndex].textContent;
			this._selectedIndex = lastSelectedOptionIndex;
		} else {
			this._text = "";
			this._selectedIndex = -1;
		}

		if (lastSelectedOptionIndex === -1 && opts[0]) {
			opts[0].selected = true;
			this.options[0].selected = true;
			this._selectedIndex = 0;
			this._text = this.options[0].textContent;
		}

		this._syncedOptions = opts;
	}

	_enableFormSupport() {
		const FormSupport = getFeature("FormSupport");
		if (FormSupport) {
			FormSupport.syncNativeHiddenInput(this, (element, nativeInput) => {
				nativeInput.disabled = element.disabled;
				nativeInput.value = element._currentlySelectedOption.value;
			});
		} else if (this.name) {
			console.warn(`In order for the "name" property to have effect, you should also: import "@ui5/webcomponents/dist/features/InputElementsFormSupport.js";`); // eslint-disable-line
		}
	}

	_onkeydown(event) {
		const isTab = (isTabNext(event) || isTabPrevious(event));

		if (isTab && this.responsivePopover && this.responsivePopover.opened) {
			this.responsivePopover.close();
		}

		if (isShow(event)) {
			event.preventDefault();
			this._toggleRespPopover();
		}

		if (isSpace(event)) {
			event.preventDefault();
		}

		if (!this._isPickerOpen) {
			this._handleArrowNavigation(event, true);
		}
	}

	_onkeyup(event) {
		if (isSpace(event) && !this._isPickerOpen) {
			this._toggleRespPopover();
		}
	}

	_getSelectedItemIndex(item) {
		return [].indexOf.call(item.parentElement.children, item);
	}

	_select(index) {
		this.options[this._selectedIndex].selected = false;
		this._selectedIndex = index;
		this.options[index].selected = true;
	}

	/**
	 * The user clicked on an item from the list
	 * @private
	 */
	_handleItemPress(event) {
		const item = event.detail.item;
		const selectedItemIndex = this._getSelectedItemIndex(item);
		this._select(selectedItemIndex);

		this._toggleRespPopover();
	}

	/**
	 * The user used arrow up/down on the list
	 * @private
	 */
	_handleSelectionChange(event) {
		const item = event.detail.selectedItems[0];
		const selectedItemIndex = this._getSelectedItemIndex(item);
		this._select(selectedItemIndex);
	}

	_applyFocusAfterOpen() {
		if (!this._currentlySelectedOption) {
			return;
		}

		const li = this.responsivePopover.querySelector(`#${this._currentlySelectedOption._id}-li`);

		li.parentElement._itemNavigation.currentIndex = this._selectedIndex;
		li && li.focus();
	}

	_handlePickerKeydown(event) {
		if (isEscape(event) && this._isPickerOpen) {
			this._escapePressed = true;
		}

		if (isEnter(event) || isSpace(event)) {
			this._shouldClosePopover = true;
		}
	}

	_handleArrowNavigation(event, shouldFireEvent) {
		let nextIndex = -1;
		const currentIndex = this._selectedIndex;
		const isDownKey = isDown(event);
		const isUpKey = isUp(event);

		if (isDownKey || isUpKey) {
			event.preventDefault();
			if (isDownKey) {
				nextIndex = this._getNextOptionIndex();
			} else {
				nextIndex = this._getPreviousOptionIndex();
			}

			this.options[this._selectedIndex].selected = false;
			this.options[nextIndex].selected = true;
			this._selectedIndex = nextIndex === -1 ? this._selectedIndex : nextIndex;

			if (currentIndex !== this._selectedIndex) {
				this.itemSelectionAnnounce();
			}

			if (shouldFireEvent) {
				this._fireChangeEvent(this.options[nextIndex]);
			}
		}
	}

	_getNextOptionIndex() {
		return this._selectedIndex === (this.options.length - 1) ? this._selectedIndex : (this._selectedIndex + 1);
	}

	_getPreviousOptionIndex() {
		return this._selectedIndex === 0 ? this._selectedIndex : (this._selectedIndex - 1);
	}

	_beforeOpen() {
		this._selectedIndexBeforeOpen = this._selectedIndex;
		this._lastSelectedOption = this.options[this._selectedIndex];
	}

	_afterClose() {
		this._iconPressed = false;
		this._listWidth = 0;

		if (this._escapePressed) {
			this._select(this._selectedIndexBeforeOpen);
			this._escapePressed = false;
		} else if (this._lastSelectedOption !== this.options[this._selectedIndex]) {
			this._fireChangeEvent(this.options[this._selectedIndex]);
			this._lastSelectedOption = this.options[this._selectedIndex];
		}
	}

	_fireChangeEvent(selectedOption) {
		this.fireEvent("change", { selectedOption });

		//  Angular two way data binding
		this.selectedItem = selectedOption;
		this.fireEvent("selected-item-changed");
	}

	get valueStateTextMappings() {
		const i18nBundle = this.i18nBundle;

		return {
			"Success": i18nBundle.getText(VALUE_STATE_SUCCESS),
			"Information": i18nBundle.getText(VALUE_STATE_INFORMATION),
			"Error": i18nBundle.getText(VALUE_STATE_ERROR),
			"Warning": i18nBundle.getText(VALUE_STATE_WARNING),
		};
	}

	get valueStateText() {
		return this.valueStateTextMappings[this.valueState];
	}

	get hasValueState() {
		return this.valueState !== ValueState.None;
	}

	get valueStateTextId() {
		return this.hasValueState ? `${this._id}-valueStateDesc` : undefined;
	}

	get isDisabled() {
		return this.disabled || undefined;
	}

	get _headerTitleText() {
		return this.i18nBundle.getText(INPUT_SUGGESTIONS_TITLE);
	}

	get _currentSelectedItem() {
		return this.shadowRoot.querySelector(`#${this.options[this._selectedIndex]._id}-li`);
	}

	get _currentlySelectedOption() {
		return this.options[this._selectedIndex];
	}

	get tabIndex() {
		return this.disabled
		|| (this.responsivePopover // Handles focus on Tab/Shift + Tab when the popover is opened
		&& this.responsivePopover.opened) ? "-1" : "0";
	}

	get classes() {
		return {
			popoverValueState: {
				"ui5-valuestatemessage-root": true,
				"ui5-valuestatemessage--success": this.valueState === ValueState.Success,
				"ui5-valuestatemessage--error": this.valueState === ValueState.Error,
				"ui5-valuestatemessage--warning": this.valueState === ValueState.Warning,
				"ui5-valuestatemessage--information": this.valueState === ValueState.Information,
			},
		};
	}

	get styles() {
		return {
			popoverHeader: {
				"width": `${this.offsetWidth}px`,
			},
			responsivePopoverHeader: {
				"display": this.options.length && this._listWidth === 0 ? "none" : "inline-block",
				"width": `${this.options.length ? this._listWidth : this.offsetWidth}px`,
			},
		};
	}

	get ariaLabelText() {
		return getEffectiveAriaLabelText(this);
	}

	get valueStateMessageText() {
		return this.getSlottedNodes("valueStateMessage").map(el => el.cloneNode(true));
	}

	get shouldDisplayDefaultValueStateMessage() {
		return !this.valueStateMessage.length && this.hasValueStateText;
	}

	get hasValueStateText() {
		return this.hasValueState && this.valueState !== ValueState.Success;
	}

	get shouldOpenValueStateMessagePopover() {
		return this.focused && this.hasValueStateText && !this._iconPressed
			&& !this._isPickerOpen && !this._isPhone;
	}

	get _isPhone() {
		return isPhone();
	}

	itemSelectionAnnounce() {
		const invisibleText = this.shadowRoot.querySelector(`#${this._id}-selectionText`);

		if (this.focused && !this._isPickerOpen && this._currentlySelectedOption) {
			invisibleText.textContent = this._currentlySelectedOption.textContent;
		} else {
			invisibleText.textContent = "";
		}
	}

	async openValueStatePopover() {
		this.popover = await this._getPopover();
		if (this.popover) {
			this.popover.openBy(this);
		}
	}

	closeValueStatePopover() {
		this.popover && this.popover.close();
	}

	toggleValueStatePopover(open) {
		if (open) {
			this.openValueStatePopover();
		} else {
			this.closeValueStatePopover();
		}
	}

	async _getPopover() {
		const staticAreaItem = await this.getStaticAreaItemDomRef();
		return staticAreaItem.querySelector("[ui5-popover]");
	}

	static get dependencies() {
		return [
			Option,
			Label,
			ResponsivePopover,
			Popover,
			List,
			StandardListItem,
			Icon,
			Button,
		];
	}
}

Select.define();

export default Select;