| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| cr.define('print_preview', function() { |
| 'use strict'; |
| |
| /** |
| * Interface to the Chromium print preview generator. |
| * @param {!print_preview.DestinationStore} destinationStore Used to get the |
| * currently selected destination. |
| * @param {!print_preview.PrintTicketStore} printTicketStore Used to read the |
| * state of the ticket and write document information. |
| * @param {!print_preview.NativeLayer} nativeLayer Used to communicate to |
| * Chromium's preview rendering system. |
| * @constructor |
| * @extends {cr.EventTarget} |
| */ |
| function PreviewGenerator(destinationStore, printTicketStore, nativeLayer) { |
| cr.EventTarget.call(this); |
| |
| /** |
| * Used to get the currently selected destination. |
| * @type {!print_preview.DestinationStore} |
| * @private |
| */ |
| this.destinationStore_ = destinationStore; |
| |
| /** |
| * Used to read the state of the ticket and write document information. |
| * @type {!print_preview.PrintTicketStore} |
| * @private |
| */ |
| this.printTicketStore_ = printTicketStore; |
| |
| /** |
| * Interface to the Chromium native layer. |
| * @type {!print_preview.NativeLayer} |
| * @private |
| */ |
| this.nativeLayer_ = nativeLayer; |
| |
| /** |
| * ID of current in-flight request. Requests that do not share this ID will |
| * be ignored. |
| * @type {number} |
| * @private |
| */ |
| this.inFlightRequestId_ = -1; |
| |
| /** |
| * Whether the previews are being generated in landscape mode. |
| * @type {boolean} |
| * @private |
| */ |
| this.isLandscapeEnabled_ = false; |
| |
| /** |
| * Whether the previews are being generated with a header and footer. |
| * @type {boolean} |
| * @private |
| */ |
| this.isHeaderFooterEnabled_ = false; |
| |
| /** |
| * Whether the previews are being generated in color. |
| * @type {boolean} |
| * @private |
| */ |
| this.isColorEnabled_ = false; |
| |
| /** |
| * Whether the document should be fitted to the page. |
| * @type {boolean} |
| * @private |
| */ |
| this.isFitToPageEnabled_ = false; |
| |
| /** |
| * Page number set used to generate the last preview. |
| * @type {print_preview.PageNumberSet} |
| * @private |
| */ |
| this.pageNumberSet_ = null; |
| |
| /** |
| * Margins type used to generate the last preview. |
| * @type {!print_preview.ticket_items.MarginsType.Value} |
| * @private |
| */ |
| this.marginsType_ = print_preview.ticket_items.MarginsType.Value.DEFAULT; |
| |
| /** |
| * Destination that was selected for the last preview. |
| * @type {print_preview.Destination} |
| * @private |
| */ |
| this.selectedDestination_ = null; |
| |
| /** |
| * Event tracker used to keep track of native layer events. |
| * @type {!EventTracker} |
| * @private |
| */ |
| this.tracker_ = new EventTracker(); |
| |
| this.addEventListeners_(); |
| }; |
| |
| /** |
| * Event types dispatched by the preview generator. |
| * @enum {string} |
| */ |
| PreviewGenerator.EventType = { |
| // Dispatched when the document can be printed. |
| DOCUMENT_READY: 'print_preview.PreviewGenerator.DOCUMENT_READY', |
| |
| // Dispatched when a page preview is ready. The previewIndex field of the |
| // event is the index of the page in the modified document, not the |
| // original. So page 4 of the original document might be previewIndex = 0 of |
| // the modified document. |
| PAGE_READY: 'print_preview.PreviewGenerator.PAGE_READY', |
| |
| // Dispatched when the document preview starts to be generated. |
| PREVIEW_START: 'print_preview.PreviewGenerator.PREVIEW_START', |
| |
| // Dispatched when the current print preview request fails. |
| FAIL: 'print_preview.PreviewGenerator.FAIL' |
| }; |
| |
| PreviewGenerator.prototype = { |
| __proto__: cr.EventTarget.prototype, |
| |
| /** |
| * Request that new preview be generated. A preview request will not be |
| * generated if the print ticket has not changed sufficiently. |
| * @return {boolean} Whether a new preview was actually requested. |
| */ |
| requestPreview: function() { |
| if (!this.printTicketStore_.isTicketValidForPreview()) { |
| return false; |
| } |
| if (!this.hasPreviewChanged_()) { |
| // Changes to these ticket items might not trigger a new preview, but |
| // they still need to be recorded. |
| this.marginsType_ = this.printTicketStore_.getMarginsType(); |
| return false; |
| } |
| this.isLandscapeEnabled_ = this.printTicketStore_.isLandscapeEnabled(); |
| this.isHeaderFooterEnabled_ = |
| this.printTicketStore_.isHeaderFooterEnabled(); |
| this.isColorEnabled_ = this.printTicketStore_.isColorEnabled(); |
| this.isFitToPageEnabled_ = this.printTicketStore_.isFitToPageEnabled(); |
| this.pageNumberSet_ = this.printTicketStore_.getPageNumberSet(); |
| this.marginsType_ = this.printTicketStore_.getMarginsType(); |
| this.selectedDestination_ = this.destinationStore_.selectedDestination; |
| |
| this.inFlightRequestId_++; |
| this.nativeLayer_.startGetPreview( |
| this.destinationStore_.selectedDestination, |
| this.printTicketStore_, |
| this.inFlightRequestId_); |
| return true; |
| }, |
| |
| /** Removes all event listeners that the preview generator has attached. */ |
| removeEventListeners: function() { |
| this.tracker_.removeAll(); |
| }, |
| |
| /** |
| * Adds event listeners to the relevant native layer events. |
| * @private |
| */ |
| addEventListeners_: function() { |
| this.tracker_.add( |
| this.nativeLayer_, |
| print_preview.NativeLayer.EventType.PAGE_LAYOUT_READY, |
| this.onPageLayoutReady_.bind(this)); |
| this.tracker_.add( |
| this.nativeLayer_, |
| print_preview.NativeLayer.EventType.PAGE_COUNT_READY, |
| this.onPageCountReady_.bind(this)); |
| this.tracker_.add( |
| this.nativeLayer_, |
| print_preview.NativeLayer.EventType.PREVIEW_RELOAD, |
| this.onPreviewReload_.bind(this)); |
| this.tracker_.add( |
| this.nativeLayer_, |
| print_preview.NativeLayer.EventType.PAGE_PREVIEW_READY, |
| this.onPagePreviewReady_.bind(this)); |
| this.tracker_.add( |
| this.nativeLayer_, |
| print_preview.NativeLayer.EventType.PREVIEW_GENERATION_DONE, |
| this.onPreviewGenerationDone_.bind(this)); |
| this.tracker_.add( |
| this.nativeLayer_, |
| print_preview.NativeLayer.EventType.PREVIEW_GENERATION_FAIL, |
| this.onPreviewGenerationFail_.bind(this)); |
| }, |
| |
| /** |
| * Dispatches a PAGE_READY event to signal that a page preview is ready. |
| * @param {number} previewIndex Index of the page with respect to the pages |
| * shown in the preview. E.g an index of 0 is the first displayed page, |
| * but not necessarily the first original document page. |
| * @param {number} pageNumber Number of the page with respect to the |
| * document. A value of 3 means it's the third page of the original |
| * document. |
| * @param {number} previewUid Unique identifier of the preview. |
| * @private |
| */ |
| dispatchPageReadyEvent_: function(previewIndex, pageNumber, previewUid) { |
| var pageGenEvent = new cr.Event(PreviewGenerator.EventType.PAGE_READY); |
| pageGenEvent.previewIndex = previewIndex; |
| pageGenEvent.previewUrl = 'chrome://print/' + previewUid.toString() + |
| '/' + (pageNumber - 1) + '/print.pdf'; |
| this.dispatchEvent(pageGenEvent); |
| }, |
| |
| /** |
| * Dispatches a PREVIEW_START event. Signals that the preview should be |
| * reloaded. |
| * @param {number} previewUid Unique identifier of the preview. |
| * @param {number} index Index of the first page of the preview. |
| * @private |
| */ |
| dispatchPreviewStartEvent_: function(previewUid, index) { |
| var previewStartEvent = new cr.Event( |
| PreviewGenerator.EventType.PREVIEW_START); |
| if (!this.printTicketStore_.isDocumentModifiable) { |
| index = -1; |
| } |
| previewStartEvent.previewUrl = 'chrome://print/' + |
| previewUid.toString() + '/' + index + '/print.pdf'; |
| this.dispatchEvent(previewStartEvent); |
| }, |
| |
| /** |
| * @return {boolean} Whether the print ticket has changed sufficiently to |
| * determine whether a new preview request should be issued. |
| * @private |
| */ |
| hasPreviewChanged_: function() { |
| var ticketStore = this.printTicketStore_; |
| return this.inFlightRequestId_ == -1 || |
| ticketStore.isLandscapeEnabled() != this.isLandscapeEnabled_ || |
| ticketStore.isHeaderFooterEnabled() != this.isHeaderFooterEnabled_ || |
| ticketStore.isColorEnabled() != this.isColorEnabled_ || |
| ticketStore.isFitToPageEnabled() != this.isFitToPageEnabled_ || |
| !ticketStore.getPageNumberSet().equals(this.pageNumberSet_) || |
| (ticketStore.getMarginsType() != this.marginsType_ && |
| ticketStore.getMarginsType() != |
| print_preview.ticket_items.MarginsType.Value.CUSTOM) || |
| (ticketStore.getMarginsType() == |
| print_preview.ticket_items.MarginsType.Value.CUSTOM && |
| !ticketStore.getCustomMargins().equals( |
| ticketStore.getDocumentMargins())) || |
| (this.selectedDestination_ != |
| this.destinationStore_.selectedDestination); |
| }, |
| |
| /** |
| * Called when the page layout of the document is ready. Always occurs |
| * as a result of a preview request. |
| * @param {cr.Event} event Contains layout info about the document. |
| * @private |
| */ |
| onPageLayoutReady_: function(event) { |
| // NOTE: A request ID is not specified, so assuming its for the current |
| // in-flight request. |
| |
| var origin = new print_preview.Coordinate2d( |
| event.pageLayout.printableAreaX, |
| event.pageLayout.printableAreaY); |
| var size = new print_preview.Size( |
| event.pageLayout.printableAreaWidth, |
| event.pageLayout.printableAreaHeight); |
| |
| var margins = new print_preview.Margins( |
| Math.round(event.pageLayout.marginTop), |
| Math.round(event.pageLayout.marginRight), |
| Math.round(event.pageLayout.marginBottom), |
| Math.round(event.pageLayout.marginLeft)); |
| |
| var o = print_preview.ticket_items.CustomMargins.Orientation; |
| var pageSize = new print_preview.Size( |
| event.pageLayout.contentWidth + |
| margins.get(o.LEFT) + margins.get(o.RIGHT), |
| event.pageLayout.contentHeight + |
| margins.get(o.TOP) + margins.get(o.BOTTOM)); |
| |
| this.printTicketStore_.updateDocumentPageInfo( |
| new print_preview.PrintableArea(origin, size), |
| pageSize, |
| event.hasCustomPageSizeStyle, |
| margins); |
| }, |
| |
| /** |
| * Called when the document page count is received from the native layer. |
| * Always occurs as a result of a preview request. |
| * @param {cr.Event} event Contains the document's page count. |
| * @private |
| */ |
| onPageCountReady_: function(event) { |
| if (this.inFlightRequestId_ != event.previewResponseId) { |
| return; // Ignore old response. |
| } |
| this.printTicketStore_.updatePageCount(event.pageCount); |
| this.pageNumberSet_ = this.printTicketStore_.getPageNumberSet(); |
| }, |
| |
| /** |
| * Called when the print preview should be reloaded. |
| * @param {cr.Event} event Contains the preview UID and request ID. |
| * @private |
| */ |
| onPreviewReload_: function(event) { |
| if (this.inFlightRequestId_ != event.previewResponseId) { |
| return; // Ignore old response. |
| } |
| var pageNumberSet = this.printTicketStore_.getPageNumberSet(); |
| this.dispatchPreviewStartEvent_( |
| event.previewUid, pageNumberSet.getPageNumberAt(0) - 1); |
| for (var i = 0; i < pageNumberSet.size; i++) { |
| var pageNumber = pageNumberSet.getPageNumberAt(i); |
| this.dispatchPageReadyEvent_(i, pageNumber, event.previewUid); |
| } |
| cr.dispatchSimpleEvent(this, PreviewGenerator.EventType.DOCUMENT_READY); |
| }, |
| |
| /** |
| * Called when a page's preview has been generated. Dispatches a |
| * PAGE_READY event. |
| * @param {cr.Event} event Contains the page index and preview UID. |
| * @private |
| */ |
| onPagePreviewReady_: function(event) { |
| if (this.inFlightRequestId_ != event.previewResponseId) { |
| return; // Ignore old response. |
| } |
| var pageNumber = event.pageIndex + 1; |
| if (this.printTicketStore_.getPageNumberSet().hasPageNumber(pageNumber)) { |
| var previewIndex = this.printTicketStore_.getPageNumberSet() |
| .getPageNumberIndex(pageNumber); |
| if (previewIndex == 0) { |
| this.dispatchPreviewStartEvent_(event.previewUid, event.pageIndex); |
| } |
| this.dispatchPageReadyEvent_( |
| previewIndex, pageNumber, event.previewUid); |
| } |
| }, |
| |
| /** |
| * Called when the preview generation is complete. Dispatches a |
| * DOCUMENT_READY event. |
| * @param {cr.Event} event Contains the preview UID and response ID. |
| * @private |
| */ |
| onPreviewGenerationDone_: function(event) { |
| if (this.inFlightRequestId_ != event.previewResponseId) { |
| return; // Ignore old response. |
| } |
| // Dispatch a PREVIEW_START event since non-modifiable documents don't |
| // trigger PAGE_READY events. |
| if (!this.printTicketStore_.isDocumentModifiable) { |
| this.dispatchPreviewStartEvent_(event.previewUid, 0); |
| } |
| cr.dispatchSimpleEvent(this, PreviewGenerator.EventType.DOCUMENT_READY); |
| }, |
| |
| /** |
| * Called when the preview generation fails. |
| * @private |
| */ |
| onPreviewGenerationFail_: function() { |
| // NOTE: No request ID is returned from Chromium so its assumed its the |
| // current one. |
| cr.dispatchSimpleEvent(this, PreviewGenerator.EventType.FAIL); |
| } |
| }; |
| |
| // Export |
| return { |
| PreviewGenerator: PreviewGenerator |
| }; |
| }); |
