Upstream Chrome on iOS source code [10/11].

ios/chrome/browser/web/external_app_launcher.mm

+// Copyright 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.
+
+#import "ios/chrome/browser/web/external_app_launcher.h"
+
+#include "base/ios/weak_nsobject.h"
+#include "base/logging.h"
+#include "base/metrics/histogram.h"
+#include "base/strings/sys_string_conversions.h"
+#include "components/strings/grit/components_strings.h"
+#include "ios/chrome/browser/experimental_flags.h"
+#import "ios/chrome/browser/open_url_util.h"
+#include "ios/chrome/grit/ios_strings.h"
+#import "net/base/mac/url_conversions.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "url/gurl.h"
+
+namespace {
+
+typedef void (^AlertHandler)(UIAlertAction* action);
+
+// Returns a set of NSStrings that are URL schemes for iTunes Stores.
+NSSet<NSString*>* ITMSSchemes() {
+  static NSSet<NSString*>* schemes;
+  static dispatch_once_t once;
+  dispatch_once(&once, ^{
+    schemes =
+        [[NSSet setWithObjects:@"itms", @"itmss", @"itms-apps", @"itms-appss",
+                               // There's no evidence that itms-bookss is
+                               // actually supported, but over-inclusion
+                               // costs less than under-inclusion.
+                               @"itms-books", @"itms-bookss", nil] retain];
+  });
+  return schemes;
+}
+
+bool UrlHasAppStoreScheme(const GURL& gURL) {
+  std::string scheme = gURL.scheme();
+  return [ITMSSchemes() containsObject:base::SysUTF8ToNSString(scheme)];
+}
+
+// Logs an entry for |Tab.ExternalApplicationOpened|.  If the user decided to
+// open in an external app, pass true.  Otherwise, if the user cancelled the
+// opening, pass false.
+void RecordExternalApplicationOpened(bool opened) {
+  UMA_HISTOGRAM_BOOLEAN("Tab.ExternalApplicationOpened", opened);
+}
+
+}  // namespace
+
+@interface ExternalAppLauncher ()
+// Returns the Phone/FaceTime call argument from |URL|.
++ (NSString*)formatCallArgument:(NSURL*)URL;
+// Ask user for confirmation before dialing FaceTime destination.
+- (void)openFaceTimePromptForURL:(NSURL*)telURL;
+// Ask user for confirmation before moving to external app.
+- (void)openExternalAppWithPromptForURL:(NSURL*)URL;
+// Presents a configured alert controller on the root view controller.
+- (void)presentAlertControllerWithMessage:(NSString*)message
+                                openTitle:(NSString*)openTitle
+                              openHandler:(AlertHandler)openHandler
+                            cancelHandler:(AlertHandler)cancelHandler;
+@end
+
+@implementation ExternalAppLauncher
+
++ (NSString*)formatCallArgument:(NSURL*)URL {
+  NSCharacterSet* charSet =
+      [NSCharacterSet characterSetWithCharactersInString:@"/"];
+  NSString* scheme = [NSString stringWithFormat:@"%@:", [URL scheme]];
+  NSString* URLString = [URL absoluteString];
+  if ([URLString length] <= [scheme length])
+    return URLString;
+  NSString* prompt = [[[[URL absoluteString] substringFromIndex:[scheme length]]
+      stringByTrimmingCharactersInSet:charSet] stringByRemovingPercentEncoding];
+  // Returns original URL string if there's nothing interesting to display
+  // other than the scheme itself.
+  if (![prompt length])
+    return URLString;
+  return prompt;
+}
+
+- (void)openExternalAppWithPromptForURL:(NSURL*)URL {
+  NSString* message = l10n_util::GetNSString(IDS_IOS_OPEN_IN_ANOTHER_APP);
+  NSString* openTitle =
+      l10n_util::GetNSString(IDS_IOS_APP_LAUNCHER_OPEN_APP_BUTTON_LABEL);
+  [self presentAlertControllerWithMessage:message
+      openTitle:openTitle
+      openHandler:^(UIAlertAction* action) {
+        RecordExternalApplicationOpened(true);
+        OpenUrlWithCompletionHandler(URL, nil);
+      }
+      cancelHandler:^(UIAlertAction* action) {
+        RecordExternalApplicationOpened(false);
+      }];
+}
+
+- (void)openFaceTimePromptForURL:(NSURL*)URL {
+  NSString* openTitle = l10n_util::GetNSString(IDS_IOS_FACETIME_BUTTON);
+  [self presentAlertControllerWithMessage:[[self class] formatCallArgument:URL]
+                                openTitle:openTitle
+                              openHandler:^(UIAlertAction* action) {
+                                OpenUrlWithCompletionHandler(URL, nil);
+                              }
+                            cancelHandler:nil];
+}
+
+- (void)presentAlertControllerWithMessage:(NSString*)message
+                                openTitle:(NSString*)openTitle
+                              openHandler:(AlertHandler)openHandler
+                            cancelHandler:(AlertHandler)cancelHandler {
+  UIAlertController* alertController =
+      [UIAlertController alertControllerWithTitle:nil
+                                          message:message
+                                   preferredStyle:UIAlertControllerStyleAlert];
+  UIAlertAction* openAction =
+      [UIAlertAction actionWithTitle:openTitle
+                               style:UIAlertActionStyleDefault
+                             handler:openHandler];
+  UIAlertAction* cancelAction =
+      [UIAlertAction actionWithTitle:l10n_util::GetNSString(IDS_CANCEL)
+                               style:UIAlertActionStyleCancel
+                             handler:cancelHandler];
+  [alertController addAction:cancelAction];
+  [alertController addAction:openAction];
+
+  [[[[UIApplication sharedApplication] keyWindow] rootViewController]
+      presentViewController:alertController
+                   animated:YES
+                 completion:nil];
+}
+
+- (BOOL)openURL:(const GURL&)gURL linkClicked:(BOOL)linkClicked {
+  if (!gURL.is_valid() || !gURL.has_scheme())
+    return NO;
+  NSURL* URL = net::NSURLWithGURL(gURL);
+
+  if (gURL.SchemeIs("facetime") || gURL.SchemeIs("facetime-audio")) {
+    // Showing an alert view immediately has a side-effect where focus is
+    // taken from the UIWebView so quickly that mouseup events are lost and
+    // buttons get 'stuck' in the on position. The solution is to defer
+    // showing the view.
+    [self performSelector:@selector(openFaceTimePromptForURL:)
+               withObject:URL
+               afterDelay:0.0];
+    return YES;
+  }
+
+  // Use telprompt instead of tel because telprompt returns user back to
+  // Chrome after phone call is completed/aborted.
+  if (gURL.SchemeIs("tel")) {
+    GURL::Replacements replacements;
+    replacements.SetSchemeStr("telprompt");
+    URL = net::NSURLWithGURL(gURL.ReplaceComponents(replacements));
+    DCHECK([[URL scheme] isEqualToString:@"telprompt"]);
+  }
+
+  // Don't open external application if chrome is not active.
+  if ([[UIApplication sharedApplication] applicationState] !=
+      UIApplicationStateActive)
+    return NO;
+
+  if (experimental_flags::IsExternalApplicationPromptEnabled()) {
+    // Prompt user to open itunes when opening it is not a result of a link
+    // click.
+    if (!linkClicked && UrlHasAppStoreScheme(gURL)) {
+      [self performSelector:@selector(openExternalAppWithPromptForURL:)
+                 withObject:URL
+                 afterDelay:0.0];
+      return YES;
+    }
+  }
+
+  // If the following call returns YES, an external application is about to be
+  // launched and Chrome will go into the background now.
+  // TODO(crbug.com/622735): This call still needs to be updated.
+  // It's heavily nested so some refactoring is needed.
+  return [[UIApplication sharedApplication] openURL:URL];
+}
+
+@end