// Copyright (c) 2022 Alibaba Group Holding Ltd.
//
// 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 "extensions/bot_detect/plugin.h"

#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "include/proxy-wasm/context.h"
#include "include/proxy-wasm/null.h"

namespace proxy_wasm {
namespace null_plugin {
namespace bot_detect {

NullPluginRegistry* context_registry_;
RegisterNullVmPluginFactory register_bot_detect_plugin("bot_detect", []() {
  return std::make_unique<NullPlugin>(bot_detect::context_registry_);
});

class MockContext : public proxy_wasm::ContextBase {
 public:
  MockContext(WasmBase* wasm) : ContextBase(wasm) {}

  MOCK_METHOD(BufferInterface*, getBuffer, (WasmBufferType));
  MOCK_METHOD(WasmResult, log, (uint32_t, std::string_view));
  MOCK_METHOD(WasmResult, getHeaderMapValue,
              (WasmHeaderMapType /* type */, std::string_view /* key */,
               std::string_view* /*result */));
  MOCK_METHOD(WasmResult, getHeaderMapPairs, (WasmHeaderMapType, Pairs*));
  MOCK_METHOD(WasmResult, sendLocalResponse,
              (uint32_t /* response_code */, std::string_view /* body */,
               Pairs /* additional_headers */, uint32_t /* grpc_status */,
               std::string_view /* details */));
  MOCK_METHOD(WasmResult, getProperty, (std::string_view, std::string*));
};

class BotDetectTest : public ::testing::Test {
 protected:
  BotDetectTest() {
    // Initialize test VM
    test_vm_ = createNullVm();
    wasm_base_ = std::make_unique<WasmBase>(
        std::move(test_vm_), "test-vm", "", "",
        std::unordered_map<std::string, std::string>{},
        AllowedCapabilitiesMap{});
    wasm_base_->load("bot_detect");
    wasm_base_->initialize();

    // Initialize host side context
    mock_context_ = std::make_unique<MockContext>(wasm_base_.get());
    current_context_ = mock_context_.get();

    ON_CALL(*mock_context_, log(testing::_, testing::_))
        .WillByDefault([](uint32_t, std::string_view m) {
          std::cerr << m << "\n";
          return WasmResult::Ok;
        });

    ON_CALL(*mock_context_, getHeaderMapValue(WasmHeaderMapType::RequestHeaders,
                                              testing::_, testing::_))
        .WillByDefault([&](WasmHeaderMapType, std::string_view header,
                           std::string_view* result) {
          if (header == ":authority") {
            *result = authority_;
          }
          if (header == "user-agent") {
            *result = user_agent_;
          }
          return WasmResult::Ok;
        });

    ON_CALL(*mock_context_, getProperty(testing::_, testing::_))
        .WillByDefault([&](std::string_view path, std::string* result) {
          *result = route_name_;
          return WasmResult::Ok;
        });

    // Initialize Wasm sandbox context
    root_context_ = std::make_unique<PluginRootContext>(0, "");
    context_ = std::make_unique<PluginContext>(1, root_context_.get());
  }
  ~BotDetectTest() override {}

  std::unique_ptr<WasmBase> wasm_base_;
  std::unique_ptr<WasmVm> test_vm_;
  std::unique_ptr<MockContext> mock_context_;

  std::unique_ptr<PluginRootContext> root_context_;
  std::unique_ptr<PluginContext> context_;

  std::string authority_;
  std::string route_name_;
  std::string user_agent_;
};

TEST_F(BotDetectTest, UseDefault) {
  std::string configuration = R"(
{
   "blocked_code": 404
})";

  BufferBase buffer;
  buffer.set({configuration.data(), configuration.size()});

  EXPECT_CALL(*mock_context_, getBuffer(WasmBufferType::PluginConfiguration))
      .WillOnce([&buffer](WasmBufferType) { return &buffer; });
  EXPECT_TRUE(root_context_->onConfigure(configuration.size()));

  user_agent_ = "BaiduMobaider/1.1.0";
  EXPECT_CALL(*mock_context_, sendLocalResponse(404, testing::_, testing::_,
                                                testing::_, testing::_));
  EXPECT_EQ(context_->onRequestHeaders(0, false),
            FilterHeadersStatus::StopIteration);

  user_agent_ = "Go-client";
  EXPECT_EQ(context_->onRequestHeaders(0, false),
            FilterHeadersStatus::Continue);
}

TEST_F(BotDetectTest, UseAllowAndDeny) {
  std::string configuration = R"(
{
   "blocked_code": 404,
   "allow": ["BaiduMobaider.*"],
   "deny": ["Go-client"]
})";

  BufferBase buffer;
  buffer.set({configuration.data(), configuration.size()});

  EXPECT_CALL(*mock_context_, getBuffer(WasmBufferType::PluginConfiguration))
      .WillOnce([&buffer](WasmBufferType) { return &buffer; });
  EXPECT_TRUE(root_context_->onConfigure(configuration.size()));

  user_agent_ = "BaiduMobaider/1.1.0";
  EXPECT_EQ(context_->onRequestHeaders(0, false),
            FilterHeadersStatus::Continue);

  user_agent_ = "Go-client";
  EXPECT_CALL(*mock_context_, sendLocalResponse(404, testing::_, testing::_,
                                                testing::_, testing::_));
  EXPECT_EQ(context_->onRequestHeaders(0, false),
            FilterHeadersStatus::StopIteration);
}

TEST_F(BotDetectTest, UseEmptyConfig) {
  std::string configuration = R"()";

  BufferBase buffer;
  buffer.set({configuration.data(), configuration.size()});

  EXPECT_TRUE(root_context_->onConfigure(configuration.size()));

  user_agent_ = "BaiduMobaider/1.1.0";
  EXPECT_CALL(*mock_context_, sendLocalResponse(403, testing::_, testing::_,
                                                testing::_, testing::_));
  EXPECT_EQ(context_->onRequestHeaders(0, false),
            FilterHeadersStatus::StopIteration);

  user_agent_ = "Go-client";
  EXPECT_EQ(context_->onRequestHeaders(0, false),
            FilterHeadersStatus::Continue);
}

}  // namespace bot_detect
}  // namespace null_plugin
}  // namespace proxy_wasm