widget/nsPaper.cpp

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsPaper.h"
   7 #include "nsPaperMargin.h"
   8 #include "nsPrinterBase.h"
   9 #include "mozilla/ErrorResult.h"
  10 #include "mozilla/dom/Promise.h"
  11
  12 using mozilla::ErrorResult;
  13 using mozilla::PaperInfo;
  14
  15 NS_IMPL_CYCLE_COLLECTION(nsPaper, mMarginPromise, mPrinter)
  16
  17 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsPaper)
  18   NS_INTERFACE_MAP_ENTRY(nsIPaper)
  19   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIPaper)
  20 NS_INTERFACE_MAP_END
  21
  22 NS_IMPL_CYCLE_COLLECTING_ADDREF(nsPaper)
  23 NS_IMPL_CYCLE_COLLECTING_RELEASE(nsPaper)
  24
  25 nsPaper::nsPaper(const mozilla::PaperInfo& aInfo)
  26     : mPrinter(nullptr), mInfo(aInfo) {}
  27
  28 nsPaper::nsPaper(nsPrinterBase& aPrinter, const mozilla::PaperInfo& aInfo)
  29     : mPrinter(&aPrinter), mInfo(aInfo) {}
  30
  31 nsPaper::~nsPaper() = default;
  32
  33 NS_IMETHODIMP
  34 nsPaper::GetId(nsAString& aId) {
  35   aId = mInfo.mId;
  36   return NS_OK;
  37 }
  38
  39 NS_IMETHODIMP
  40 nsPaper::GetName(nsAString& aName) {
  41   aName = mInfo.mName.IsEmpty() ? mInfo.mId : mInfo.mName;
  42   return NS_OK;
  43 }
  44
  45 NS_IMETHODIMP
  46 nsPaper::GetWidth(double* aWidth) {
  47   NS_ENSURE_ARG_POINTER(aWidth);
  48   *aWidth = mInfo.mSize.Width();
  49   return NS_OK;
  50 }
  51
  52 NS_IMETHODIMP
  53 nsPaper::GetHeight(double* aHeight) {
  54   NS_ENSURE_ARG_POINTER(aHeight);
  55   *aHeight = mInfo.mSize.Height();
  56   return NS_OK;
  57 }
  58
  59 NS_IMETHODIMP
  60 nsPaper::GetUnwriteableMargin(JSContext* aCx, Promise** aPromise) {
  61   if (RefPtr<Promise> existing = mMarginPromise) {
  62     existing.forget(aPromise);
  63     return NS_OK;
  64   }
  65   ErrorResult rv;
  66   RefPtr<Promise> promise = Promise::Create(xpc::CurrentNativeGlobal(aCx), rv);
  67   if (MOZ_UNLIKELY(rv.Failed())) {
  68     return rv.StealNSResult();
  69   }
  70
  71   mMarginPromise = promise;
  72
  73   if (mInfo.mUnwriteableMargin) {
  74     auto margin = mozilla::MakeRefPtr<nsPaperMargin>(*mInfo.mUnwriteableMargin);
  75     mMarginPromise->MaybeResolve(margin);
  76   } else {
  77     if (mPrinter) {
  78       mPrinter->QueryMarginsForPaper(*mMarginPromise, mInfo.mId);
  79     } else {
  80       MOZ_ASSERT_UNREACHABLE("common paper sizes should know their margins");
  81       mMarginPromise->MaybeRejectWithNotSupportedError("Margins unavailable");
  82     }
  83   }
  84
  85   promise.forget(aPromise);
  86   return NS_OK;
  87 }