/*
 * Copyright (C) 2023 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
#include "policy_engine.h"
#include "wv_cdm_event_listener.h"
#include <fuzzer/FuzzedDataProvider.h>

using namespace wvcdm;
using namespace wvcdm::metrics;
using namespace video_widevine;

static constexpr int32_t kLicenseIdVersion = 1;
static constexpr int32_t kMaxByte = 256;
static constexpr int32_t kMinResolution = 1;
static constexpr int32_t kMaxResolution = 1024;
static constexpr int32_t kMaxEntitledKey = 5;
const KeyId kSigningKeyId = "signing_key";
const KeyId kEntitlementKeyId = "entitlementkeyid";
const char *kRenewalServerUrl =
    "https://test.google.com/license/GetCencLicense";

class FuzzWvCdmEventListener : public WvCdmEventListener {
  void OnSessionRenewalNeeded(const CdmSessionId & /*session_id*/) {}
  void OnSessionKeysChange(const CdmSessionId & /*session_id*/,
                           const CdmKeyStatusMap & /*keys_status*/,
                           bool /*has_new_usable_key*/) {}
  void OnExpirationUpdate(const CdmSessionId & /*session_id*/,
                          int64_t /*new_expiry_time_seconds*/) {}
};

class PolicyEngineFuzzer {
 public:
  PolicyEngineFuzzer(const uint8_t *data, size_t size) : fdp_(data, size){};
  void Process();

 private:
  FuzzedDataProvider fdp_;
  KeyId key_id_;
  License license_;
  void SetUp();
};

void PolicySetBool(std::function<void(bool)> function,
                   FuzzedDataProvider *fdp) {
  if (fdp->ConsumeBool()) {
    function(fdp->ConsumeBool());
  }
}

void PolicySetInt64(std::function<void(int64_t)> function,
                    FuzzedDataProvider *fdp) {
  if (fdp->ConsumeBool()) {
    function(fdp->ConsumeIntegral<int64_t>());
  }
}

void PolicyEngineFuzzer::SetUp() {

  License::KeyContainer *key = license_.add_key();
  int32_t key_type = fdp_.ConsumeIntegralInRange<uint8_t>(
      License::KeyContainer::SIGNING, License::KeyContainer::ENTITLEMENT);
  key->set_type((License_KeyContainer_KeyType)key_type);
  key_id_ = fdp_.ConsumeRandomLengthString(kMaxByte);

  LicenseIdentification *id = license_.mutable_id();
  if (fdp_.ConsumeBool()) {
    id->set_version(kLicenseIdVersion);
  }
  if (fdp_.ConsumeBool()) {
    id->set_type(fdp_.ConsumeBool() ? STREAMING : OFFLINE);
  }
  if (fdp_.ConsumeBool()) {
    id->set_provider_session_token(fdp_.ConsumeRandomLengthString(kMaxByte));
  }

  if (fdp_.ConsumeBool()) {
    license_.set_license_start_time(fdp_.ConsumeIntegral<int64_t>());
  }

  if (fdp_.ConsumeBool()) {
    License_KeyContainer_OutputProtection *output_protection =
        key->mutable_required_protection();
    License_KeyContainer_OutputProtection_HDCP hdcp_level =
        (License_KeyContainer_OutputProtection_HDCP)fdp_
            .ConsumeIntegralInRange<uint8_t>(HDCP_NONE, HDCP_NO_DIGITAL_OUTPUT);
    output_protection->set_hdcp(hdcp_level);
  }

  if (fdp_.ConsumeBool()) {
    const std::string iv_string = fdp_.ConsumeRandomLengthString(kMaxByte);
    key->set_iv(iv_string);
  }

  switch (key_type) {
    case License::KeyContainer::SIGNING: {
      if (fdp_.ConsumeBool()) {
        key_id_ = fdp_.ConsumeBool() ? kSigningKeyId : key_id_;
        key->set_id(key_id_);
      }
      break;
    }
    case License::KeyContainer::CONTENT: {
      if (fdp_.ConsumeBool()) {
        key->set_id(key_id_);
      }
      if (fdp_.ConsumeBool()) {
        int32_t level = fdp_.ConsumeIntegralInRange<uint8_t>(
        License::KeyContainer::SW_SECURE_CRYPTO,
        License::KeyContainer::HW_SECURE_ALL);
        key->set_level((License_KeyContainer_SecurityLevel)level);
      }
      License_Policy *policy = license_.mutable_policy();
      PolicySetBool(
            std::bind(&License_Policy::set_can_play, policy, std::placeholders::_1),
            &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_can_persist, policy,
                              std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_can_renew, policy,
                              std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_renew_with_usage, policy,
                              std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_soft_enforce_rental_duration,
                              policy, std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_soft_enforce_playback_duration,
                              policy, std::placeholders::_1), &fdp_);

      PolicySetInt64(std::bind(&License_Policy::set_rental_duration_seconds,
                               policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(std::bind(&License_Policy::set_playback_duration_seconds,
                               policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(std::bind(&License_Policy::set_license_duration_seconds,
                               policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(std::bind(&License_Policy::set_renewal_recovery_duration_seconds,
                               policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(std::bind(&License_Policy::set_renewal_retry_interval_seconds, policy,
                               std::placeholders::_1), &fdp_);
      PolicySetInt64(std::bind(&License_Policy::set_renewal_delay_seconds, policy,
                               std::placeholders::_1), &fdp_);

      if (fdp_.ConsumeBool()) {
        video_widevine::License::Policy::TimerDelayBase time_delay_base =
          (video_widevine::License::Policy::TimerDelayBase)
              fdp_.ConsumeIntegralInRange<uint8_t>(
                  License_Policy_TimerDelayBase_TIMER_DELAY_BASE_UNSPECIFIED,
                  License_Policy_TimerDelayBase_FIRST_DECRYPT);
        policy->set_initial_renewal_delay_base(time_delay_base);
      }

      if (fdp_.ConsumeBool()) {
        std::string serverUrl = fdp_.ConsumeBool()
                                  ? kRenewalServerUrl
                                  : fdp_.ConsumeRandomLengthString(kMaxByte);
      policy->set_renewal_server_url(serverUrl);
      }
      break;
    }
    case License::KeyContainer::KEY_CONTROL: {
      key->set_type(License::KeyContainer::KEY_CONTROL);
      // No control bits for this type of key container used for license
      break;
    }
    case License::KeyContainer::OPERATOR_SESSION: {
      key->set_type(License::KeyContainer::OPERATOR_SESSION);
      if (fdp_.ConsumeBool()) {
        key->set_id(key_id_);
      }

      if (fdp_.ConsumeBool()) {
        int32_t level = fdp_.ConsumeIntegralInRange<uint8_t>(
            License::KeyContainer::SW_SECURE_CRYPTO,
            License::KeyContainer::HW_SECURE_ALL);
        key->set_level((License_KeyContainer_SecurityLevel)level);
      }

      if (fdp_.ConsumeBool()) {
        PolicySetBool(std::bind(&License_Policy::set_can_persist,license_.mutable_policy(),
                              std::placeholders::_1),&fdp_);
      }

      License::KeyContainer::OperatorSessionKeyPermissions *permissions =
          key->mutable_operator_session_key_permissions();
      PolicySetBool(
          std::bind(&License::KeyContainer::OperatorSessionKeyPermissions::
                        set_allow_encrypt,
                    permissions, std::placeholders::_1), &fdp_);
      PolicySetBool(
          std::bind(&License::KeyContainer::OperatorSessionKeyPermissions::
                        set_allow_decrypt,
                    permissions, std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License::KeyContainer::
                                  OperatorSessionKeyPermissions::set_allow_sign,
                              permissions, std::placeholders::_1), &fdp_);
      PolicySetBool(
          std::bind(&License::KeyContainer::OperatorSessionKeyPermissions::
                        set_allow_signature_verify,
                    permissions, std::placeholders::_1), &fdp_);
      break;
    }
    case License::KeyContainer::ENTITLEMENT:
    default: {
      if (fdp_.ConsumeBool()) {
        key_id_ = fdp_.ConsumeBool() ? kEntitlementKeyId : key_id_;
        key->set_id(key_id_);
      }
      if (fdp_.ConsumeBool()) {
        int32_t level = fdp_.ConsumeIntegralInRange<uint8_t>(
            License::KeyContainer::SW_SECURE_CRYPTO,
            License::KeyContainer::HW_SECURE_ALL);
        key->set_level((License_KeyContainer_SecurityLevel)level);
      }

      License_Policy *policy = license_.mutable_policy();
      PolicySetBool(
          std::bind(&License_Policy::set_can_play, policy, std::placeholders::_1),
          &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_can_persist, policy,
                              std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_can_renew, policy,
                              std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_renew_with_usage, policy,
                              std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_soft_enforce_rental_duration,
                              policy, std::placeholders::_1), &fdp_);
      PolicySetBool(std::bind(&License_Policy::set_soft_enforce_playback_duration,
                              policy, std::placeholders::_1), &fdp_);

      PolicySetInt64(std::bind(&License_Policy::set_rental_duration_seconds,
                              policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(std::bind(&License_Policy::set_playback_duration_seconds,
                              policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(std::bind(&License_Policy::set_license_duration_seconds,
                              policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(
          std::bind(&License_Policy::set_renewal_recovery_duration_seconds,
                    policy, std::placeholders::_1), &fdp_);
      PolicySetInt64(
          std::bind(&License_Policy::set_renewal_retry_interval_seconds, policy,
                    std::placeholders::_1), &fdp_);
      PolicySetInt64(
          std::bind(&License_Policy::set_renewal_delay_seconds, policy,
                    std::placeholders::_1), &fdp_);

      if (fdp_.ConsumeBool()) {
        video_widevine::License::Policy::TimerDelayBase time_delay_base =
          (video_widevine::License::Policy::TimerDelayBase)
              fdp_.ConsumeIntegralInRange<uint8_t>(
                  License_Policy_TimerDelayBase_TIMER_DELAY_BASE_UNSPECIFIED,
                  License_Policy_TimerDelayBase_FIRST_DECRYPT);
        policy->set_initial_renewal_delay_base(time_delay_base);
      }
      break;
    }
  }
}

void PolicyEngineFuzzer::Process() {
  SetUp();
  FuzzWvCdmEventListener fuzz_wv_cdm_event_listener;
  CdmSessionId session_id = fdp_.ConsumeRandomLengthString(kMaxByte);
  metrics::CryptoMetrics crypto_metrics;
  std::unique_ptr<CryptoSession> cryptoSession(
      wvcdm::CryptoSession::MakeCryptoSession(&crypto_metrics));
  std::unique_ptr<PolicyEngine> policy_engine(new PolicyEngine(
      session_id, &fuzz_wv_cdm_event_listener, cryptoSession.get()));

  while (fdp_.remaining_bytes()) {
    auto invokePolicyEngineAPI =
        fdp_.PickValueInArray<const std::function<void()>>({
            [&]() { policy_engine->CanDecryptContent(key_id_); },
            [&]() { policy_engine->CanUseKeyForSecurityLevel(key_id_); },
            [&]() { policy_engine->OnTimerEvent(); },
            [&]() {
              policy_engine->SetLicense(
                  license_, fdp_.ConsumeBool() /*defer_license_state_update**/);
            },
            [&]() {
              int32_t max_entitled_key=
                  fdp_.ConsumeIntegralInRange<uint8_t>(1, kMaxEntitledKey);
              std::vector<WidevinePsshData_EntitledKey> entitled_keys(
                  max_entitled_key);
              for (int i = 0; i < max_entitled_key; ++i) {
                entitled_keys[i].set_entitlement_key_id(
                    fdp_.ConsumeRandomLengthString(kMaxByte));
                entitled_keys[i].set_key_id(
                    fdp_.ConsumeBool()
                        ? fdp_.ConsumeRandomLengthString(kMaxByte)
                        : key_id_);
              }
              policy_engine->SetEntitledLicenseKeys(entitled_keys);
            },
            [&]() { policy_engine->SetLicenseForRelease(license_); },
            [&]() { policy_engine->BeginDecryption(); },
            [&]() { policy_engine->DecryptionEvent(); },
            [&]() {
              policy_engine->UpdateLicense(
                  license_, fdp_.ConsumeBool() /*defer_license_state_update*/);
            },
            [&]() {
              policy_engine->UpdateLicenseState(
                  fdp_.ConsumeIntegral<int64_t>() /*current_time*/);
            },
            [&]() {
              int32_t width = fdp_.ConsumeIntegralInRange<int32_t>(
                  kMinResolution, kMaxResolution);
              int32_t height = fdp_.ConsumeIntegralInRange<int32_t>(
                  kMinResolution, kMaxResolution);
              policy_engine->NotifyResolution(width, height);
            },
            [&]() { policy_engine->NotifySessionExpiration(); },
            [&]() {
              CdmQueryMap query_info;
              policy_engine->Query(&query_info);
            },
            [&]() {
              CdmKeyAllowedUsage key_usage;
              policy_engine->QueryKeyAllowedUsage(
                  key_id_, (fdp_.ConsumeBool() ? nullptr : &key_usage));
            },
            [&]() {
              policy_engine->RestorePlaybackTimes(
                  fdp_.ConsumeIntegral<int64_t>() /*playback_start_time*/,
                  fdp_.ConsumeIntegral<int64_t>() /*last_playback_time*/,
                  fdp_.ConsumeIntegral<int64_t>() /*grace_period_end_time*/);
            },
            [&]() {
              policy_engine->HasLicenseOrRentalOrPlaybackDurationExpired(
                  fdp_.ConsumeIntegral<int64_t>());
            },
        });
    invokePolicyEngineAPI();
  }
}

extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  PolicyEngineFuzzer policy_engine_fuzzer(data, size);
  policy_engine_fuzzer.Process();
  return 0;
}