// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "components/pdf/browser/plugin_response_writer.h"

#include <stddef.h>

#include <memory>
#include <string>
#include <utility>

#include "base/containers/span.h"
#include "base/functional/callback.h"
#include "base/functional/callback_helpers.h"
#include "base/memory/scoped_refptr.h"
#include "base/run_loop.h"
#include "base/strings/string_view_util.h"
#include "base/test/mock_callback.h"
#include "base/test/task_environment.h"
#include "mojo/public/cpp/bindings/receiver.h"
#include "mojo/public/cpp/system/data_pipe.h"
#include "mojo/public/cpp/system/data_pipe_drainer.h"
#include "net/base/net_errors.h"
#include "net/http/http_response_headers.h"
#include "services/network/public/cpp/url_loader_completion_status.h"
#include "services/network/public/mojom/url_response_head.mojom.h"
#include "services/network/test/mock_url_loader_client.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "url/gurl.h"

namespace pdf {

namespace {

using ::network::MockURLLoaderClient;

using ::testing::HasSubstr;
using ::testing::NiceMock;
using ::testing::Not;

class BodyDrainer {
 public:
  explicit BodyDrainer(mojo::ScopedDataPipeConsumerHandle body)
      : drainer_(&drainer_client_, std::move(body)) {}

  const std::string& content() const { return drainer_client_.content; }

  void WaitComplete() {
    if (drainer_client_.is_complete)
      return;

    base::RunLoop run_loop;
    ASSERT_FALSE(drainer_client_.quit_closure);
    drainer_client_.quit_closure = run_loop.QuitClosure();
    run_loop.Run();

    EXPECT_TRUE(drainer_client_.is_complete);
  }

 private:
  struct DrainerClient : public mojo::DataPipeDrainer::Client {
    void OnDataAvailable(base::span<const uint8_t> data) override {
      content.append(base::as_string_view(data));
    }

    void OnDataComplete() override {
      is_complete = true;
      if (quit_closure)
        std::move(quit_closure).Run();
    }

    std::string content;
    bool is_complete = false;
    base::OnceClosure quit_closure;
  };

  DrainerClient drainer_client_;
  mojo::DataPipeDrainer drainer_;
};

class PluginResponseWriterTest : public testing::Test {
 protected:
  PluginResponseWriterTest() {
    ON_CALL(mock_client_, OnReceiveResponse)
        .WillByDefault(
            [this](network::mojom::URLResponseHeadPtr head,
                   mojo::ScopedDataPipeConsumerHandle body,
                   std::optional<mojo_base::BigBuffer> cached_metadata) {
              body_drainer_ = std::make_unique<BodyDrainer>(std::move(body));
            });
  }

  std::unique_ptr<PluginResponseWriter> NewPluginResponseWriter(
      const PdfStreamDelegate::StreamInfo& stream_info) {
    return std::make_unique<PluginResponseWriter>(
        stream_info, client_receiver_.BindNewPipeAndPassRemote());
  }

  // Returns the generated response after sending it.
  std::string GenerateResponse(const PdfStreamDelegate::StreamInfo& stream) {
    auto response_writer = NewPluginResponseWriter(stream);

    base::RunLoop run_loop;
    EXPECT_CALL(mock_client_, OnComplete).WillOnce([&run_loop]() {
      run_loop.Quit();
    });
    response_writer->Start(base::DoNothing());
    run_loop.Run();

    // Waiting for `URLLoaderClient::OnComplete()` ensures `body_drainer_` is
    // set, but the data pipe may still have unread data.
    body_drainer_->WaitComplete();

    return body_drainer_->content();
  }

  base::test::TaskEnvironment task_environment_;
  NiceMock<MockURLLoaderClient> mock_client_;
  mojo::Receiver<network::mojom::URLLoaderClient> client_receiver_{
      &mock_client_};

  std::unique_ptr<BodyDrainer> body_drainer_;
};

}  // namespace

TEST_F(PluginResponseWriterTest, Start) {
  const std::string kFakeScript = "fake-script";

  PdfStreamDelegate::StreamInfo stream;
  stream.stream_url = GURL("chrome-extension://id/stream-url");
  stream.original_url = GURL("https://example.test/fake.pdf");
  stream.injected_script = &kFakeScript;
  stream.background_color = SK_ColorGREEN;
  stream.full_frame = true;
  stream.allow_javascript = true;
  auto response_writer = NewPluginResponseWriter(stream);

  base::RunLoop run_loop;

  {
    // Note that `URLLoaderClient` operations are received on a separate
    // sequence, and only are ordered with respect to each other.
    testing::InSequence in_sequence;

    EXPECT_CALL(mock_client_, OnReceiveResponse)
        .WillOnce([this](network::mojom::URLResponseHeadPtr head,
                         mojo::ScopedDataPipeConsumerHandle body,
                         std::optional<mojo_base::BigBuffer> cached_metadata) {
          EXPECT_EQ(200, head->headers->response_code());
          EXPECT_EQ("text/html", head->mime_type);
          body_drainer_ = std::make_unique<BodyDrainer>(std::move(body));
        });

    EXPECT_CALL(mock_client_, OnComplete)
        .WillOnce(
            [&run_loop](const network::URLLoaderCompletionStatus& status) {
              EXPECT_EQ(net::OK, status.error_code);
              run_loop.Quit();
            });
  }

  // Note that `done_callback` is not ordered with respect to the
  // `URLLoaderClient` operations.
  base::MockCallback<base::OnceClosure> done_callback;
  EXPECT_CALL(done_callback, Run);

  response_writer->Start(done_callback.Get());
  run_loop.Run();

  // Waiting for `URLLoaderClient::OnComplete()` ensures `body_drainer_` is set,
  // but the data pipe may still have unread data.
  ASSERT_TRUE(body_drainer_);
  body_drainer_->WaitComplete();

  EXPECT_THAT(body_drainer_->content(),
              HasSubstr("src=\"chrome-extension://id/stream-url\""));
  EXPECT_THAT(body_drainer_->content(),
              HasSubstr("original-url=\"https://example.test/fake.pdf\""));
  EXPECT_THAT(body_drainer_->content(), HasSubstr(kFakeScript));
  EXPECT_THAT(body_drainer_->content(),
              HasSubstr("background-color=\"4278255360\""));
  EXPECT_THAT(body_drainer_->content(), HasSubstr("javascript=\"allow\""));
  EXPECT_THAT(body_drainer_->content(), HasSubstr("full-frame"));
}

TEST_F(PluginResponseWriterTest, StartWithUnescapedUrls) {
  PdfStreamDelegate::StreamInfo stream;
  stream.stream_url = GURL("chrome-extension://id/stream-url\"");
  stream.original_url = GURL("https://example.test/\"fake.pdf");
  std::string response = GenerateResponse(stream);

  EXPECT_THAT(response,
              HasSubstr("src=\"chrome-extension://id/stream-url%22\""));
  EXPECT_THAT(response,
              HasSubstr("original-url=\"https://example.test/%22fake.pdf\""));
}

TEST_F(PluginResponseWriterTest, StartForPrintPreview) {
  PdfStreamDelegate::StreamInfo stream;
  stream.stream_url = GURL("chrome-untrusted://print/1/0/print.pdf");
  stream.original_url = GURL("chrome-untrusted://print/1/0/print.pdf");
  std::string response = GenerateResponse(stream);

  EXPECT_THAT(response,
              HasSubstr("src=\"chrome-untrusted://print/1/0/print.pdf\""));
  EXPECT_THAT(
      response,
      HasSubstr("original-url=\"chrome-untrusted://print/1/0/print.pdf\""));
}

TEST_F(PluginResponseWriterTest, StartWithoutInjectedScript) {
  PdfStreamDelegate::StreamInfo stream;
  stream.injected_script = nullptr;
  std::string response = GenerateResponse(stream);

  EXPECT_THAT(response, Not(HasSubstr("fake-script")));
}

TEST_F(PluginResponseWriterTest, StartWithBackgroundColor) {
  PdfStreamDelegate::StreamInfo stream;
  stream.background_color = SK_ColorBLUE;
  std::string response = GenerateResponse(stream);

  EXPECT_THAT(response, HasSubstr("background-color=\"4278190335\""));
}

TEST_F(PluginResponseWriterTest, StartWithNonFullFrame) {
  PdfStreamDelegate::StreamInfo stream;
  stream.full_frame = false;
  std::string response = GenerateResponse(stream);

  EXPECT_THAT(response, Not(HasSubstr("full-frame")));
}

TEST_F(PluginResponseWriterTest, StartWithJavaScriptDisabled) {
  PdfStreamDelegate::StreamInfo stream;
  stream.allow_javascript = false;
  std::string response = GenerateResponse(stream);

  EXPECT_THAT(response, HasSubstr("javascript=\"block\""));
}

}  // namespace pdf