// Copyright 2013 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/signin/android_profile_oauth2_token_service.h"

#include "base/android/jni_android.h"
#include "base/android/jni_array.h"
#include "base/android/jni_string.h"
#include "base/bind.h"
#include "base/logging.h"
#include "chrome/browser/profiles/profile_android.h"
#include "chrome/browser/signin/profile_oauth2_token_service_factory.h"
#include "chrome/browser/sync/profile_sync_service_android.h"
#include "content/public/browser/browser_thread.h"
#include "jni/OAuth2TokenService_jni.h"

using base::android::AttachCurrentThread;
using base::android::ConvertJavaStringToUTF8;
using base::android::ConvertUTF8ToJavaString;
using base::android::ScopedJavaLocalRef;
using content::BrowserThread;

namespace {

std::string CombineScopes(const OAuth2TokenService::ScopeSet& scopes) {
  // The Android AccountManager supports multiple scopes separated by a space:
  // https://code.google.com/p/google-api-java-client/wiki/OAuth2#Android
  std::string scope;
  for (OAuth2TokenService::ScopeSet::const_iterator it = scopes.begin();
       it != scopes.end(); ++it) {
    if (!scope.empty())
      scope += " ";
    scope += *it;
  }
  return scope;
}

// Callback from FetchOAuth2TokenWithUsername().
// Arguments:
// - the error, or NONE if the token fetch was successful.
// - the OAuth2 access token.
// - the expiry time of the token (may be null, indicating that the expiry
//   time is unknown.
typedef base::Callback<void(
    const GoogleServiceAuthError&, const std::string&, const base::Time&)>
        FetchOAuth2TokenCallback;

}  // namespace

AndroidProfileOAuth2TokenService::AndroidProfileOAuth2TokenService() {
  JNIEnv* env = AttachCurrentThread();
  base::android::ScopedJavaLocalRef<jobject> local_java_ref =
      Java_OAuth2TokenService_create(env, reinterpret_cast<intptr_t>(this));
  java_ref_.Reset(env, local_java_ref.obj());
}

AndroidProfileOAuth2TokenService::~AndroidProfileOAuth2TokenService() {}

// static
jobject AndroidProfileOAuth2TokenService::GetForProfile(
    JNIEnv* env, jclass clazz, jobject j_profile_android) {
  Profile* profile = ProfileAndroid::FromProfileAndroid(j_profile_android);
  AndroidProfileOAuth2TokenService* service =
      ProfileOAuth2TokenServiceFactory::GetPlatformSpecificForProfile(profile);
  return service->java_ref_.obj();
}

static jobject GetForProfile(JNIEnv* env,
                             jclass clazz,
                             jobject j_profile_android) {
  return AndroidProfileOAuth2TokenService::GetForProfile(
      env, clazz, j_profile_android);
}

bool AndroidProfileOAuth2TokenService::RefreshTokenIsAvailable(
    const std::string& account_id) const {
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jstring> j_account_id =
      ConvertUTF8ToJavaString(env, account_id);
  jboolean refresh_token_is_available =
      Java_OAuth2TokenService_hasOAuth2RefreshToken(
          env, base::android::GetApplicationContext(),
          j_account_id.obj());
  return refresh_token_is_available != JNI_FALSE;
}

std::vector<std::string> AndroidProfileOAuth2TokenService::GetAccounts() {
  std::vector<std::string> accounts;
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jobjectArray> j_accounts =
      Java_OAuth2TokenService_getAccounts(
          env, base::android::GetApplicationContext());
  // TODO(fgorski): We may decide to filter out some of the accounts.
  base::android::AppendJavaStringArrayToStringVector(env,
                                                     j_accounts.obj(),
                                                     &accounts);
  return accounts;
}

std::vector<std::string> AndroidProfileOAuth2TokenService::GetSystemAccounts() {
  std::vector<std::string> accounts;
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jobjectArray> j_accounts =
      Java_OAuth2TokenService_getSystemAccounts(
          env, base::android::GetApplicationContext());
  base::android::AppendJavaStringArrayToStringVector(env,
                                                     j_accounts.obj(),
                                                     &accounts);
  return accounts;
}

void AndroidProfileOAuth2TokenService::FetchOAuth2Token(
    RequestImpl* request,
    const std::string& account_id,
    net::URLRequestContextGetter* getter,
    const std::string& client_id,
    const std::string& client_secret,
    const OAuth2TokenService::ScopeSet& scopes) {
  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
  DCHECK(!account_id.empty());

  JNIEnv* env = AttachCurrentThread();
  std::string scope = CombineScopes(scopes);
  ScopedJavaLocalRef<jstring> j_username =
      ConvertUTF8ToJavaString(env, account_id);
  ScopedJavaLocalRef<jstring> j_scope =
      ConvertUTF8ToJavaString(env, scope);

  // Allocate a copy of the request WeakPtr on the heap, because the object
  // needs to be passed through JNI as an int.
  // It will be passed back to OAuth2TokenFetched(), where it will be freed.
  scoped_ptr<FetchOAuth2TokenCallback> heap_callback(
      new FetchOAuth2TokenCallback(base::Bind(&RequestImpl::InformConsumer,
                                              request->AsWeakPtr())));

  // Call into Java to get a new token.
  Java_OAuth2TokenService_getOAuth2AuthToken(
      env, base::android::GetApplicationContext(),
      j_username.obj(),
      j_scope.obj(),
      reinterpret_cast<intptr_t>(heap_callback.release()));
}

OAuth2AccessTokenFetcher*
AndroidProfileOAuth2TokenService::CreateAccessTokenFetcher(
    const std::string& account_id,
    net::URLRequestContextGetter* getter,
    OAuth2AccessTokenConsumer* consumer) {
  NOTREACHED();
  return NULL;
}

void AndroidProfileOAuth2TokenService::InvalidateOAuth2Token(
    const std::string& account_id,
    const std::string& client_id,
    const ScopeSet& scopes,
    const std::string& access_token) {
  OAuth2TokenService::InvalidateOAuth2Token(account_id,
                                            client_id,
                                            scopes,
                                            access_token);

  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jstring> j_access_token =
      ConvertUTF8ToJavaString(env, access_token);
  Java_OAuth2TokenService_invalidateOAuth2AuthToken(
      env, base::android::GetApplicationContext(),
      j_access_token.obj());
}

void AndroidProfileOAuth2TokenService::ValidateAccounts(
    JNIEnv* env,
    jobject obj,
    jstring j_current_acc) {
  std::string signed_in_account = ConvertJavaStringToUTF8(env, j_current_acc);
  ValidateAccounts(signed_in_account);
}

void AndroidProfileOAuth2TokenService::ValidateAccounts(
    const std::string& signed_in_account) {
  std::vector<std::string> prev_ids = GetAccounts();
  std::vector<std::string> curr_ids = GetSystemAccounts();
  std::vector<std::string> refreshed_ids;
  std::vector<std::string> revoked_ids;

  if (!ValidateAccounts(
      signed_in_account, prev_ids, curr_ids, refreshed_ids, revoked_ids)) {
    curr_ids.clear();
  }

  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jobjectArray> java_accounts(
      base::android::ToJavaArrayOfStrings(env, curr_ids));
  Java_OAuth2TokenService_saveStoredAccounts(
      env, base::android::GetApplicationContext(), java_accounts.obj());

  for (std::vector<std::string>::iterator it = refreshed_ids.begin();
       it != refreshed_ids.end(); it++) {
    FireRefreshTokenAvailable(*it);
  }

  for (std::vector<std::string>::iterator it = revoked_ids.begin();
       it != revoked_ids.end(); it++) {
    FireRefreshTokenRevoked(*it);
  }
}

bool AndroidProfileOAuth2TokenService::ValidateAccounts(
    const std::string& signed_in_account,
    const std::vector<std::string>& prev_account_ids,
    const std::vector<std::string>& curr_account_ids,
    std::vector<std::string>& refreshed_ids,
    std::vector<std::string>& revoked_ids) {
  if (std::find(curr_account_ids.begin(),
                curr_account_ids.end(),
                signed_in_account) != curr_account_ids.end()) {
    // Test to see if an account is removed from the Android AccountManager.
    // If so, invoke FireRefreshTokenRevoked to notify the reconcilor.
    for (std::vector<std::string>::const_iterator it = prev_account_ids.begin();
         it != prev_account_ids.end(); it++) {
      if (*it == signed_in_account)
        continue;

      if (std::find(curr_account_ids.begin(),
                    curr_account_ids.end(),
                    *it) == curr_account_ids.end()) {
        revoked_ids.push_back(*it);
      }
    }

    // Always fire the primary signed in account first.
    refreshed_ids.push_back(signed_in_account);

    for (std::vector<std::string>::const_iterator it = curr_account_ids.begin();
         it != curr_account_ids.end(); it++) {
      if (*it != signed_in_account) {
        refreshed_ids.push_back(*it);
      }
    }
    return true;
  } else {
    // Currently signed in account does not any longer exist among accounts on
    // system together with all other accounts.
    if (!signed_in_account.empty()) {
      revoked_ids.push_back(signed_in_account);
    }
    for (std::vector<std::string>::const_iterator it = prev_account_ids.begin();
         it != prev_account_ids.end(); it++) {
      if (*it == signed_in_account)
        continue;
      revoked_ids.push_back(*it);
    }
    return false;
  }
}

void AndroidProfileOAuth2TokenService::FireRefreshTokenAvailableFromJava(
    JNIEnv* env,
    jobject obj,
    const jstring account_name) {
  std::string account_id = ConvertJavaStringToUTF8(env, account_name);
  AndroidProfileOAuth2TokenService::FireRefreshTokenAvailable(account_id);
}

void AndroidProfileOAuth2TokenService::FireRefreshTokenAvailable(
    const std::string& account_id) {
  // Notify native observers.
  OAuth2TokenService::FireRefreshTokenAvailable(account_id);
  // Notify Java observers.
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jstring> account_name =
      ConvertUTF8ToJavaString(env, account_id);
  Java_OAuth2TokenService_notifyRefreshTokenAvailable(
      env, java_ref_.obj(), account_name.obj());
}

void AndroidProfileOAuth2TokenService::FireRefreshTokenRevokedFromJava(
    JNIEnv* env,
    jobject obj,
    const jstring account_name) {
  std::string account_id = ConvertJavaStringToUTF8(env, account_name);
  AndroidProfileOAuth2TokenService::FireRefreshTokenRevoked(account_id);
}

void AndroidProfileOAuth2TokenService::FireRefreshTokenRevoked(
    const std::string& account_id) {
  // Notify native observers.
  OAuth2TokenService::FireRefreshTokenRevoked(account_id);
  // Notify Java observers.
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jstring> account_name =
      ConvertUTF8ToJavaString(env, account_id);
  Java_OAuth2TokenService_notifyRefreshTokenRevoked(
      env, java_ref_.obj(), account_name.obj());
}

void AndroidProfileOAuth2TokenService::FireRefreshTokensLoadedFromJava(
    JNIEnv* env,
    jobject obj) {
  AndroidProfileOAuth2TokenService::FireRefreshTokensLoaded();
}

void AndroidProfileOAuth2TokenService::FireRefreshTokensLoaded() {
  // Notify native observers.
  OAuth2TokenService::FireRefreshTokensLoaded();
  // Notify Java observers.
  JNIEnv* env = AttachCurrentThread();
  Java_OAuth2TokenService_notifyRefreshTokensLoaded(
      env, java_ref_.obj());
}

void AndroidProfileOAuth2TokenService::RevokeAllCredentials() {
  std::vector<std::string> accounts = GetAccounts();
  for (std::vector<std::string>::iterator it = accounts.begin();
       it != accounts.end(); it++) {
    FireRefreshTokenRevoked(*it);
  }
}

// Called from Java when fetching of an OAuth2 token is finished. The
// |authToken| param is only valid when |result| is true.
void OAuth2TokenFetched(JNIEnv* env, jclass clazz,
    jstring authToken,
    jboolean result,
    jlong nativeCallback) {
  std::string token = ConvertJavaStringToUTF8(env, authToken);
  scoped_ptr<FetchOAuth2TokenCallback> heap_callback(
      reinterpret_cast<FetchOAuth2TokenCallback*>(nativeCallback));
  // Android does not provide enough information to know if the credentials are
  // wrong, so assume any error is transient by using CONNECTION_FAILED.
  GoogleServiceAuthError err(result ?
                             GoogleServiceAuthError::NONE :
                             GoogleServiceAuthError::CONNECTION_FAILED);
  heap_callback->Run(err, token, base::Time());
}

// static
bool AndroidProfileOAuth2TokenService::Register(JNIEnv* env) {
  return RegisterNativesImpl(env);
}