/*
 * 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.$pane = $( '<div>' )
				.addClass( 'mw-mmv-download-pane' )
				.appendTo( this.$container );

			this.$downloadArea = $( '<div>' )
				.addClass( 'mw-mmv-download-area' )
				.appendTo( this.$pane );

			this.createDownloadButton( this.$downloadArea );
			this.createSizePulldownMenu( this.$downloadArea );
			this.createPreviewLink( this.$downloadArea );

			this.formatter = new EmbedFileFormatter();
			this.currentAttrView = 'plain';
			this.createAttributionButton( this.$pane );

			/**
			 * Default item for the size menu.
			 *
			 * @property {OO.ui.MenuOptionWidget}
			 */
			this.defaultItem = this.downloadSizeMenu.getMenu().findSelectedItem();

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

		/**
		 * Fired when the attribution call to action panel is clicked.
		 * @event DownloadPane#mmv-download-cta-open
		 */

		/**
		 * Fired when the attribution area is closed.
		 * @event DownloadPane#mmv-download-cta-close
		 */

		/**
		 * 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( $container ) {
			// TODO: Use OOUI progressive button widget instead
			this.$downloadButton = $( '<a>' )
				.attr( 'target', '_blank' )
				.attr( 'download', '' )
				.addClass( 'mw-ui-button mw-ui-progressive mw-mmv-download-go-button' );

			this.$selectionArrow = $( '<span>' )
				.addClass( 'mw-ui-button mw-ui-progressive mw-mmv-download-select-menu' )
				.append(
					$( '<span>' )
						.addClass( 'mw-mmv-download-image-size-name' )
						.text( '\u00A0' )
				)
				.append(
					$( '<span>' )
						.addClass( 'mw-mmv-download-image-size' )
						.text( '\u00A0' )
				);

			$container
				.append( this.$downloadButton )
				.append( this.$selectionArrow );
		}

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

			$container.append( this.downloadSizeMenu.$element );
		}

		/**
		 * Creates preview link.
		 *
		 * @param {jQuery} $container
		 */
		createPreviewLink( $container ) {
			this.$previewLink = $( '<a>' )
				.attr( 'target', '_blank' )
				.addClass( 'mw-mmv-download-preview-link' )
				.text( mw.message( 'multimediaviewer-download-preview-link-title' ).text() )
				.appendTo( $container );
		}
		createAttributionButton( $container ) {
			const attributionInput = new mw.widgets.CopyTextLayout( {
				align: 'top',
				button: {
					label: '',
					title: mw.msg( 'multimediaviewer-download-attribution-copy' )
				}
			} );
			const attributionSwitch = new OO.ui.ButtonSelectWidget( {
				classes: [ 'mw-mmv-download-attr-select' ]
			} );
			const plainOption = new OO.ui.ButtonOptionWidget( {
				data: 'plain',
				label: mw.message( 'multimediaviewer-attr-plain' ).text()
			} );
			const htmlOption = new OO.ui.ButtonOptionWidget( {
				data: 'html',
				label: mw.message( 'multimediaviewer-attr-html' ).text()
			} );

			attributionSwitch.addItems( [
				plainOption,
				htmlOption
			] );

			attributionSwitch.selectItem( plainOption );

			attributionSwitch.on( 'select', ( selection ) => {
				this.selectAttribution( selection.getData() );

				this.attributionInput.selectText();
			} );

			this.$attributionSection = $( '<div>' )
				.addClass( 'mw-mmv-download-attribution mw-mmv-download-attribution-collapsed' )
				.appendTo( $container )
				.on( 'click', () => {
					if ( this.$attributionSection.hasClass( 'mw-mmv-download-attribution-collapsed' ) ) {
						this.$container.trigger( 'mmv-download-cta-open' );
						this.$attributionSection.removeClass( 'mw-mmv-download-attribution-collapsed' );
						this.attributionInput.selectText();
					}
				} );

			this.$attributionCtaHeader = $( '<p>' )
				.addClass( 'mw-mmv-download-attribution-cta-header' )
				.text( mw.message( 'multimediaviewer-download-attribution-cta-header' ).text() );
			this.$attributionCta = $( '<div>' )
				.addClass( 'mw-mmv-download-attribution-cta' )
				.append(
					this.$attributionCtaHeader,
					$( '<p>' )
						.addClass( 'mw-mmv-download-attribution-cta-invite' )
						.text( mw.message( 'multimediaviewer-download-attribution-cta' ).text() )
				)
				.appendTo( this.$attributionSection );
			this.attributionInput = attributionInput;

			this.$attributionHowHeader = $( '<p>' )
				.addClass( 'mw-mmv-download-attribution-how-header' )
				.text( mw.message( 'multimediaviewer-download-attribution-cta-header' ).text() );
			this.$attributionHow = $( '<div>' )
				.addClass( 'mw-mmv-download-attribution-how' )
				.append(
					this.$attributionHowHeader,
					this.attributionInput.$element,
					new OO.ui.FieldLayout( attributionSwitch, { align: 'top' } ).$element,
					$( '<p>' )
						.addClass( 'mw-mmv-download-attribution-close-button' )
						.on( 'click', ( e ) => {
							this.$container.trigger( 'mmv-download-cta-close' );
							this.$attributionSection.addClass( 'mw-mmv-download-attribution-collapsed' );
							e.stopPropagation();
						} )
						.text( ' ' )
				)
				.appendTo( this.$attributionSection );
		}

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

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

		/**
		 * Registers listeners.
		 */
		attach() {
			// Register handlers for switching between file sizes
			this.downloadSizeMenu.getMenu().on( 'choose', ( item ) => this.handleSizeSwitch( item ) );
			this.$selectionArrow.on( 'click', () => this.downloadSizeMenu.getMenu().toggle() );
		}

		/**
		 * Clears listeners.
		 */
		unattach() {
			super.unattach();

			this.downloadSizeMenu.getMenu().off( 'choose' );
			this.$selectionArrow.off( 'click' );
		}

		/**
		 * Handles size menu change events.
		 *
		 * @param {OO.ui.MenuOptionWidget} item
		 */
		handleSizeSwitch( item ) {
			const value = item.getData();

			if ( value.name === 'original' && this.image !== null ) {
				this.setDownloadUrl( this.image.url );
				this.setButtonText( value.name, this.getExtensionFromUrl( this.image.url ),
					value.width, value.height );
			} else {
				// Disable download while we get the image
				this.$downloadButton.addClass( 'disabledLink' );
				// Set a temporary message. It will be updated once we have the file type.
				this.setButtonText( value.name, this.imageExtension, value.width, value.height );

				this.utils.getThumbnailUrlPromise( value.width ).done( ( thumbnail ) => {
					this.setDownloadUrl( thumbnail.url );
					this.setButtonText( value.name, this.getExtensionFromUrl( thumbnail.url ),
						value.width, value.height );
				} );
			}
		}

		/**
		 * 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 of the download button.
		 *
		 * @param {string} sizeClass A size class such as 'small'
		 * @param {string} extension file extension
		 * @param {number} width
		 * @param {number} height
		 */
		setButtonText( sizeClass, extension, width, height ) {
			// The following messages are used here:
			// * multimediaviewer-download-original-button-name
			// * multimediaviewer-download-small-button-name
			// * multimediaviewer-download-medium-button-name
			// * multimediaviewer-download-large-button-name
			// * multimediaviewer-download-xl-button-name
			const sizeClassMessage = mw.message( `multimediaviewer-download-${sizeClass}-button-name` ).text();
			const dimensionMessage = mw.message( 'multimediaviewer-embed-dimensions', width, height ).text();
			const sizeMessage = mw.message( 'multimediaviewer-embed-dimensions-with-file-format',
				dimensionMessage, extension ).text();

			// Update button label and size strings to reflect new selected size
			this.$downloadButton.html(
				`<span class="mw-mmv-download-image-size-name">${sizeClassMessage}</span>` +
				`<span class="mw-mmv-download-image-size">${sizeMessage}</span>`
			);
		}

		/**
		 * 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 sizeOptions = this.downloadSizeMenu.getMenu().getItems();
			const sizes = this.utils.getPossibleImageSizesForHtml( image.width, image.height );

			this.image = image;

			this.utils.updateMenuOptions( sizes, sizeOptions );

			this.downloadSizeMenu.$element.addClass( 'active' );

			// 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.getMenu().chooseItem( this.defaultItem );

			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.$attributionCtaHeader.text( mw.message( attributionCtaMessage ).text() );
			// eslint-disable-next-line mediawiki/msg-doc
			this.$attributionHowHeader.text( mw.message( attributionCtaMessage ).text() );
		}

		/**
		 * @inheritdoc
		 */
		empty() {
			this.downloadSizeMenu.getMenu().toggle( false );
			this.downloadSizeMenu.$element.removeClass( 'active' );

			this.$downloadButton.attr( 'href', '' );
			this.$previewLink.attr( 'href', '' );
			this.imageExtension = undefined;

			this.image = null;
		}
	}

	module.exports = DownloadPane;
}() );