[Offline pages] Refactor URL conversions from TabAndroid

chrome/browser/android/offline_pages/offline_page_utils.cc

+// Copyright 2015 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.
+
+#include "chrome/browser/android/offline_pages/offline_page_utils.h"
+
+#include "base/strings/string_piece.h"
+#include "base/strings/string_util.h"
+#include "chrome/browser/android/offline_pages/offline_page_mhtml_archiver.h"
+#include "chrome/browser/android/offline_pages/offline_page_model_factory.h"
+#include "components/offline_pages/offline_page_feature.h"
+#include "components/offline_pages/offline_page_item.h"
+#include "components/offline_pages/offline_page_model.h"
+#include "content/public/browser/browser_context.h"
+#include "url/gurl.h"
+
+namespace offline_pages {
+namespace android {
+
+namespace {
+
+// Returns an offline page related to the |online_url\, if one exists in the

[jianli, 2015/12/15 01:45:24]

\ => |
also, suggest removing if part since it causes confusion and adds no value.
 // Returns an offline page that is originated from |online_url|.

[fgorski, 2015/12/15 16:33:01]

Done.

+// |browser_context|.
+const offline_pages::OfflinePageItem* GetOfflinePageByOnlineURL(
+    content::BrowserContext* browser_context,
+    const GURL& online_url) {
+  DCHECK(browser_context);
+
+  if (!offline_pages::IsOfflinePagesEnabled())
+    return nullptr;
+
+  offline_pages::OfflinePageModel* offline_page_model =
+      offline_pages::OfflinePageModelFactory::GetForBrowserContext(
+          browser_context);
+  if (!offline_page_model)
+    return nullptr;
+
+  return offline_page_model->GetPageByOnlineURL(online_url);
+}
+
+// Returns an offline page related to the |offline_url\, if one exists in the

[jianli, 2015/12/15 01:45:24]

\ => |
also, suggest removing if part since it causes confusion and adds no value.
 // Returns an offline page that is stored as |offline_url|.

[fgorski, 2015/12/15 16:33:01]

Done.

+// |browser_context|.
+const offline_pages::OfflinePageItem* GetOfflinePageByOfflineURL(
+    content::BrowserContext* browser_context,
+    const GURL& offline_url) {
+  DCHECK(browser_context);
+
+  if (!offline_pages::IsOfflinePagesEnabled())
+    return nullptr;
+
+  // Note that we first check if the url likely points to an offline page
+  // before calling GetPageByOfflineURL in order to avoid unnecessary lookup
+  // cost.
+  if (!MightBeOfflineURL(offline_url))
+    return nullptr;
+
+  offline_pages::OfflinePageModel* offline_page_model =
+      offline_pages::OfflinePageModelFactory::GetForBrowserContext(
+          browser_context);
+
+  // TODO: bail out if model is null

[jianli, 2015/12/15 01:45:24]

nit: either add DCHECK or do the bailout now.

[fgorski, 2015/12/15 16:33:01]

Done.

+  return offline_page_model->GetPageByOfflineURL(offline_url);
+}
+
+}  // namespace
+
+bool MightBeOfflineURL(const GURL& url) {
+  // It has to be a file URL ending with .mhtml extension.
+  return url.is_valid() && url.SchemeIsFile() &&
+         base::EndsWith(url.spec(),
+                        OfflinePageMHTMLArchiver::GetFileNameExtension(),
+                        base::CompareCase::INSENSITIVE_ASCII);
+}
+
+GURL GetOfflineURLByOnlineURL(content::BrowserContext* browser_context,
+                              const GURL& online_url) {
+  const offline_pages::OfflinePageItem* offline_page =
+      GetOfflinePageByOnlineURL(browser_context, online_url);
+  if (!offline_page)
+    return GURL::EmptyGURL();

[jianli, 2015/12/15 01:45:24]

We should return GURL() since here we don't return GURL reference.

[fgorski, 2015/12/15 16:33:02]

Done.

+
+  return offline_page->GetOfflineURL();
+}
+
+GURL GetOnlineURLByOfflineURL(content::BrowserContext* browser_context,
+                              const GURL& offline_url) {
+  DCHECK(browser_context);
+
+  const offline_pages::OfflinePageItem* offline_page =
+      GetOfflinePageByOfflineURL(browser_context, offline_url);
+  if (!offline_page)
+    return GURL::EmptyGURL();

[jianli, 2015/12/15 01:45:24]

ditto

[fgorski, 2015/12/15 16:33:01]

Done.

+
+  return offline_page->url;
+}
+
+int64 GetBookmarkIdByOfflineURL(content::BrowserContext* browser_context,
+                                const GURL& offline_url) {
+  DCHECK(browser_context);
+
+  const offline_pages::OfflinePageItem* offline_page =
+      GetOfflinePageByOfflineURL(browser_context, offline_url);
+  if (!offline_page)
+    return -1;
+
+  return offline_page->bookmark_id;
+}
+
+bool IsOfflinePage(content::BrowserContext* browser_context,
+                   const GURL& offline_url) {
+  DCHECK(browser_context);
+
+  return GetOfflinePageByOfflineURL(browser_context, offline_url) != nullptr;
+}
+
+bool HasOfflinePageForOnlineURL(content::BrowserContext* browser_context,
+                                const GURL& online_url) {
+  const offline_pages::OfflinePageItem* offline_page =
+      GetOfflinePageByOnlineURL(browser_context, online_url);
+  return offline_page && !offline_page->file_path.empty();
+}
+
+const bool HasOfflinePages(content::BrowserContext* browser_context) {
+  DCHECK(browser_context);
+
+  if (!offline_pages::IsOfflinePagesEnabled())
+    return false;
+
+  offline_pages::OfflinePageModel* offline_page_model =
+      offline_pages::OfflinePageModelFactory::GetForBrowserContext(
+          browser_context);
+  return !offline_page_model->GetAllPages().empty();
+}
+
+}  // namespace android
+}  // namespace offline_pages