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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at */
#ifndef nsPrinterListBase_h__
#define nsPrinterListBase_h__
#include "nsIPrinterList.h"
#include "nsCycleCollectionParticipant.h"
#include "nsISupportsImpl.h"
#include "nsPaper.h"
#include "nsString.h"
class nsPrinterListBase : public nsIPrinterList {
using Promise = mozilla::dom::Promise;
NS_IMETHOD GetSystemDefaultPrinterName(nsAString& aName) final {
return SystemDefaultPrinterName(aName);
NS_IMETHOD GetPrinters(JSContext*, Promise**) final;
NS_IMETHOD GetPrinterByName(const nsAString& aPrinterName, JSContext* aCx,
Promise** aResult) final;
NS_IMETHOD GetPrinterBySystemName(const nsAString& aPrinterName,
JSContext* aCx, Promise** aResult) final;
NS_IMETHOD GetNamedOrDefaultPrinter(const nsAString& aPrinterName,
JSContext* aCx, Promise** aResult) final;
NS_IMETHOD GetFallbackPaperList(JSContext*, Promise**) final;
struct PrinterInfo {
// Both windows and CUPS: The name of the printer.
nsString mName;
// CUPS only: Handle to owned cups_dest_t.
void* mCupsHandle = nullptr;
// Called off the main thread, collect information to create an appropriate
// list of printers.
virtual nsTArray<PrinterInfo> Printers() const = 0;
// Create an nsIPrinter object given the information we obtained from the
// background thread.
virtual RefPtr<nsIPrinter> CreatePrinter(PrinterInfo) const = 0;
mozilla::Maybe<PrinterInfo> NamedOrDefaultPrinter(nsString aName) const;
// No copy or move, we're an identity.
nsPrinterListBase(const nsPrinterListBase&) = delete;
nsPrinterListBase(nsPrinterListBase&&) = delete;
virtual ~nsPrinterListBase();
// This could be implemented in terms of Printers() and then searching the
// returned printer info for a printer of the given name, but we expect
// backends to have more efficient methods of implementing this.
virtual mozilla::Maybe<PrinterInfo> PrinterByName(nsString aName) const = 0;
// Same as NamedPrinter, but uses the system name.
// Depending on whether or not there is a more efficient way to address the
// printer for a given backend, this may or may not be equivalent to
// NamedPrinter.
virtual mozilla::Maybe<PrinterInfo> PrinterBySystemName(
nsString aName) const = 0;
// This is implemented separately from the IDL interface version so that it
// can be made const, which allows it to be used while resolving promises.
virtual nsresult SystemDefaultPrinterName(nsAString&) const = 0;
// Return "paper" sizes to be supported by the Save to PDF destination;
// for actual printer drivers the list is retrieved from nsIPrinter.
nsTArray<RefPtr<nsPaper>> FallbackPaperList() const;
// Constructs mCommonPaperInfo by localizing the sizes in
// nsPaper::kCommonPaperSizes and creating corresponding PaperInfo.
void EnsureCommonPaperInfo(JSContext* aCx);
RefPtr<Promise> mPrintersPromise;
// PaperInfo for our fallback sizes and common size localization.
// This field contains the same data for every instance of this class.
// It's unfortunate that this needs to be a member rather than static data
// like nsPaper::kCommonPaperSizes, but that's because PaperInfo contains
// localized data, and we need a JSContext to do the localization.
RefPtr<const mozilla::CommonPaperInfoArray> mCommonPaperInfo;