/*
 * This file is part of the MediaWiki extension MultimediaViewer.
 *
 * MultimediaViewer is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * MultimediaViewer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with MultimediaViewer.  If not, see <http://www.gnu.org/licenses/>.
 */

const { UiElement } = require( 'mmv' );
const { EmbedFileFormatter, Utils } = require( 'mmv.ui.ondemandshareddependencies' );

( function () {

	/**
	 * UI component that provides functionality to download the media asset displayed.
	 */
	class DownloadPane extends UiElement {
		/**
		 * @param {jQuery} $container
		 */
		constructor( $container ) {
			super( $container );

			/** @property {Utils} utils - */
			this.utils = new Utils();

			this.formatter = new EmbedFileFormatter();
			this.createDownloadSection( this.$container );
			this.createAttributionButton( this.$container );

			/** @property {Image|null} Image the download button currently points to. */
			this.image = null;
		}

		/**
		 * Creates dialog download section.
		 *
		 * @param {jQuery} $container
		 */
		createDownloadSection( $container ) {
			const $header = $( '<div>' )
				.addClass( 'cdx-dialog__header' )
				.appendTo( $container );
			$( '<div>' )
				.addClass( 'cdx-dialog__header__title' )
				.text( mw.message( 'multimediaviewer-download-link' ).text() )
				.appendTo( $header );

			const $body = $( '<div>' )
				.addClass( 'cdx-dialog__body mw-mmv-pt-0' )
				.appendTo( $container );

			this.$downloadArea = $( '<div>' )
				.addClass( 'mw-mmv-flex mw-mmv-gap-50' )
				.appendTo( $body );
			this.createSizePulldownMenu( this.$downloadArea );
			this.createDownloadButton( this.$downloadArea );

			const $p = $( '<p>' ).addClass( 'mw-mmv-mt-75' ).appendTo( $body );
			this.createPreviewLink( $p );
		}

		/**
		 * Creates download split button. It is a link with the "download" property set plus an
		 * arrow that allows the user to select the image size desired. The "download" property
		 * triggers native browser downloading in browsers that support it. The fallback is the
		 * 'download' parameter which instructs the server to send the right headers so the browser
		 * downloads the file instead of just displaying it. If all this fails, the image will appear
		 * in another window/tab.
		 *
		 * @param {jQuery} $container
		 */
		createDownloadButton( $container ) {
			this.$downloadButton = $( '<a>' )
				.attr( 'target', '_blank' )
				.attr( 'download', '' )
				.addClass( 'cdx-button cdx-button--weight-primary cdx-button--action-progressive cdx-button--fake-button cdx-button--fake-button--enabled' )
				.html( '<span class="cdx-button__icon cdx-button__icon--download" aria-hidden="true"></span>' + mw.message( 'multimediaviewer-download' ).text() )
				.appendTo( $container );
		}

		/**
		 * Creates pulldown menu to select image sizes.
		 *
		 * @param {jQuery} $container
		 */
		createSizePulldownMenu( $container ) {
			this.$downloadSizeMenu = this.utils.createSelectMenu(
				[ 'original', 'small', 'medium', 'large', 'xl' ],
				'original'
			).appendTo( $container );
		}

		/**
		 * Creates preview link.
		 *
		 * @param {jQuery} $container
		 */
		createPreviewLink( $container ) {
			this.$previewLink = $( '<a>' )
				.attr( 'target', '_blank' )
				.addClass( 'cdx-docs-link' )
				.html( mw.message( 'multimediaviewer-download-preview-link-title' ).text() )
				.appendTo( $container );
		}

		createAttributionButton( $container ) {
			[ this.$attributionInput, this.$attributionInputDiv ] = this.utils.createInputWithCopy(
				mw.message( 'multimediaviewer-download-attribution-copy' ).text(), ''
			);

			const $header = $( '<div>' )
				.addClass( 'cdx-dialog__header' )
				.appendTo( $container );
			$( '<p>' )
				.addClass( 'cdx-dialog__header__title' )
				.text( mw.message( 'multimediaviewer-download-attribution' ).text() )
				.appendTo( $header );
			this.$attributionHowHeader = $( '<p>' )
				.addClass( 'mw-mmv-mb-75' )
				.text( mw.message( 'multimediaviewer-download-attribution-cta-header' ).text() );

			const $attributionTabs = $( '<div>' ).addClass( 'cdx-tabs' );
			const $attributionTabsHeader = $( '<div>' ).addClass( 'cdx-tabs__header' ).appendTo( $attributionTabs );
			this.$attributionTabsList = $( '<div>' ).addClass( 'cdx-tabs__list' ).attr( 'role', 'tablist' ).appendTo( $attributionTabsHeader );
			[ 'plain', 'html' ].forEach( ( name ) => $( '<button>' )
				.addClass( 'cdx-tabs__list__item' )
				.attr( 'role', 'tab' )
				.attr( 'data-name', name )
				// The following messages are used here:
				// * multimediaviewer-attr-plain
				// * multimediaviewer-attr-html
				.text( mw.message( 'multimediaviewer-attr-' + name ).text() )
				.on( 'click', () => this.selectAttribution( name ) )
				.appendTo( this.$attributionTabsList )
			);
			this.selectAttribution( 'plain' );

			$( '<div>' )
				.addClass( 'cdx-dialog__body mw-mmv-pt-0 mw-mmv-pb-150' )
				.append(
					this.$attributionHowHeader,
					$attributionTabs,
					this.$attributionInputDiv.addClass( ' mw-mmv-mt-75' )
				)
				.appendTo( $container );
		}

		/**
		 * Selects the specified attribution type.
		 *
		 * @param {string} [name='plain'] The attribution type to use ('plain' or 'html')
		 */
		selectAttribution( name ) {
			this.currentAttrView = name;

			this.$attributionTabsList.children().each( ( _i, element ) => {
				const $element = $( element );
				$element.attr( 'aria-selected', $element.attr( 'data-name' ) === name );
			} );

			if ( this.currentAttrView === 'html' ) {
				this.$attributionInput.val( this.htmlCredit );
			} else {
				this.$attributionInput.val( this.textCredit );
			}
		}

		/**
		 * Registers listeners.
		 */
		attach() {
			// Register handlers for switching between file sizes
			this.$downloadSizeMenu.on( 'change', () => this.handleSizeSwitch() );
		}

		/**
		 * Clears listeners.
		 */
		unattach() {
			super.unattach();
			this.$downloadSizeMenu.off( 'change' );
		}

		/**
		 * Handles size menu change events.
		 */
		handleSizeSwitch() {
			// eslint-disable-next-line no-jquery/no-sizzle
			const $option = this.$downloadSizeMenu.find( ':selected' );
			const value = {
				name: $option.attr( 'data-name' ),
				width: $option.attr( 'data-width' ),
				height: $option.attr( 'data-height' )
			};

			if ( value.name === 'original' && this.image !== null ) {
				this.setDownloadUrl( this.image.url );
			} else {
				// Disable download while we get the image
				this.$downloadButton.addClass( 'disabledLink' );
				this.utils.getThumbnailUrlPromise( value.width ).done( ( thumbnail ) => {
					this.setDownloadUrl( thumbnail.url );
				} );
			}
		}

		/**
		 * Sets the URL on the download button.
		 *
		 * @param {string} url
		 */
		setDownloadUrl( url ) {
			this.$downloadButton.attr( 'href', `${ url }?download` );
			this.$previewLink.attr( 'href', url );

			// Re-enable download
			this.$downloadButton.removeClass( 'disabledLink' );
		}

		/**
		 * Sets the text in the attribution input element.
		 *
		 * @param {Object} embed
		 * @param {Image} embed.imageInfo
		 * @param {Repo} embed.repoInfo
		 */
		setAttributionText( embed ) {
			this.htmlCredit = this.formatter.getCreditHtml( embed );
			this.textCredit = this.formatter.getCreditText( embed );
			this.selectAttribution( this.currentAttrView );
		}

		/**
		 * Chops off the extension part of an URL.
		 *
		 * @param {string} url URL
		 * @return {string} Extension
		 */
		getExtensionFromUrl( url ) {
			const urlParts = url.split( '.' );
			return urlParts[ urlParts.length - 1 ];
		}

		/**
		 * Sets the data on the element.
		 *
		 * @param {Image} image
		 * @param {Repo} repo
		 */
		set( image, repo ) {
			const license = image && image.license;
			const sizes = this.utils.getPossibleImageSizesForHtml( image.width, image.height );

			this.image = image;

			this.utils.updateSelectOptions( sizes, this.$downloadSizeMenu.children() );

			// Note: This extension will not be the real one for file types other than: png/gif/jpg/jpeg
			this.imageExtension = image.title.getExtension().toLowerCase();

			// Reset size menu to default item and update download button label now that we have the info
			this.$downloadSizeMenu.val( 'original' );
			this.handleSizeSwitch();

			if ( image && repo ) {
				const embedFileInfo = {
					imageInfo: image,
					repoInfo: repo
				};
				this.setAttributionText( embedFileInfo );
			}

			const attributionCtaMessage = ( license && license.needsAttribution() ) ?
				'multimediaviewer-download-attribution-cta-header' :
				'multimediaviewer-download-optional-attribution-cta-header';
			// Message defined above
			// eslint-disable-next-line mediawiki/msg-doc
			this.$attributionHowHeader.text( mw.message( attributionCtaMessage ).text() );
		}

		/**
		 * @inheritdoc
		 */
		empty() {
			this.$downloadButton.attr( 'href', '' );
			this.$previewLink.attr( 'href', '' );
			this.imageExtension = undefined;

			this.image = null;
		}
	}

	module.exports = DownloadPane;
}() );