/* Copyright (c) 2015, 2023, Oracle and/or its affiliates.

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License, version 2.0,
 as published by the Free Software Foundation.

 This program is also distributed with certain software (including
 but not limited to OpenSSL) that is licensed under separate terms,
 as designated in a particular file or component or in included license
 documentation.  The authors of MySQL hereby grant you an additional
 permission to link the program and your derivative works with the
 separately licensed software that they have included with MySQL.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License, version 2.0, for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA */


#include <cstdio>
#include <cstdlib>
#include <fstream>
#include <string>
#include <iostream>

#include <gtest/gtest.h>

#include "ngs/protocol/output_buffer.h"

using namespace ngs;

namespace im
{
  const ngs::Pool_config default_pool_config = { 0, 0, BUFFER_PAGE_SIZE };

  namespace tests {
    std::vector<ngs::shared_ptr<Page> > page_del;

    static void add_pages(Output_buffer &ob, const size_t no_of_pages, const size_t page_size)
    {
      for (size_t i = 0; i < no_of_pages; i++)
      {
        page_del.push_back(ngs::shared_ptr<Page>(new Page(static_cast<uint32_t>(page_size))));
        ob.push_back(page_del.back().get());
      }
    }

    TEST(OBuffer, Next)
    {
      Page_pool page_pool(default_pool_config);
      Output_buffer obuffer(page_pool);

      EXPECT_EQ(0u, obuffer.length());

      void *ptr;
      int size;

      EXPECT_TRUE(obuffer.Next(&ptr, &size));
      EXPECT_EQ(BUFFER_PAGE_SIZE, size);

      EXPECT_EQ(BUFFER_PAGE_SIZE, obuffer.ByteCount());
      EXPECT_EQ(0u + BUFFER_PAGE_SIZE, obuffer.length());
    }

    TEST(OBuffer, obuffer)
    {
      Page_pool page_pool(default_pool_config);
      Output_buffer obuffer(page_pool);

      EXPECT_EQ(0u, obuffer.length());

      EXPECT_TRUE(obuffer.add_int32(0x12345678));

      int32_t r;
      EXPECT_TRUE(obuffer.int32_at(0, r));
      EXPECT_EQ(0x12345678, r);

      EXPECT_TRUE(obuffer.add_int8(0x42));
      EXPECT_TRUE(obuffer.add_bytes("hello", 6));

      EXPECT_EQ(11u, obuffer.length());
    }

    TEST(OBuffer, split_int_write)
    {
      Page_pool page_pool(default_pool_config);
      Output_buffer obuffer(page_pool);

      add_pages(obuffer, 1, 2);
      add_pages(obuffer, 1, 4);

      EXPECT_EQ(0u, obuffer.length());
      EXPECT_EQ(6u, obuffer.available_space());

      EXPECT_TRUE(obuffer.add_int32(0x12345678));

      EXPECT_EQ(4u, obuffer.length());

      int32_t r;
      EXPECT_TRUE(obuffer.int32_at(0, r));
      EXPECT_EQ(0x12345678, r);
    }


    TEST(OBuffer, split_str_write)
    {
      Page_pool page_pool(default_pool_config);
      Output_buffer obuffer(page_pool);
      const size_t page_size = 8;
      const size_t no_of_pages = 2;

      add_pages(obuffer,no_of_pages, page_size);

      EXPECT_EQ(0u, obuffer.length());
      EXPECT_EQ(16u, obuffer.available_space());

      size_t len = strlen("helloworld");
      EXPECT_TRUE(obuffer.add_bytes("helloworld", len));

      EXPECT_EQ(len, obuffer.length());

      Buffer::Page_list &p(obuffer.pages());
      Buffer::Buffer_page &p1 = *(p.begin());
      EXPECT_EQ("hellowor", std::string(p1->data, p1->length));
      Buffer::Buffer_page &p2 = *(++p.begin());
      EXPECT_EQ("ld", std::string(p2->data, p2->length));
    }


    TEST(OBuffer, write_big_buffer)
    {
      // write 300k simulating protobuf and ensure everything got there
      char data[300001];

      data[0] = '>';
      for (size_t i = 1; i < sizeof(data)-1; i++)
        data[i] = '.';
      data[300000-1] = '<';
      data[300000] = 0;

      Page_pool page_pool(default_pool_config);
      Output_buffer obuffer(page_pool);

      int written = 0;
      char *ptr;
      int size;
      while (written < 300000 && obuffer.Next((void**)&ptr, &size))
      {
        if (written + size <= 300000)
        {
          memcpy(ptr, data + written, size);
          written += size;
        }
        else
        {
          obuffer.BackUp(size - (300000 - written));
          memcpy(ptr, data + written, (300000 - written));
          written += (300000 - written);
        }
      }

      EXPECT_EQ(300000u, obuffer.length());

      int total = 0;
      Const_buffer_sequence buffers(obuffer.get_buffers());
      for (Const_buffer_sequence::const_iterator buf = buffers.begin(); buf != buffers.end(); ++buf)
      {
        size_t size = (*buf).second;
        const char* d = (*buf).first;
        int first = 0;

        if (total == 0)
        {
          EXPECT_EQ('>', d[0]);
          first++;
        }
        total += static_cast<int>(size);
        if (total == 300000)
        {
          EXPECT_EQ('<', d[size-1]);
          size--;
        }

        for (size_t i = first; i < size; i++)
          EXPECT_EQ('.', d[i]);
      }
      EXPECT_EQ(300000, total);
    }

    TEST(OBuffer, save_rollback)
    {
      Page_pool page_pool(default_pool_config);
      Output_buffer obuffer(page_pool);
      const size_t size_of_page = 8;

      add_pages(obuffer,2, size_of_page);

      EXPECT_EQ(0u, obuffer.length());
      EXPECT_EQ(16u, obuffer.available_space());

      obuffer.save_state();

      size_t len = strlen("helloworld");
      EXPECT_TRUE(obuffer.add_bytes("helloworld", len));

      EXPECT_EQ(len, obuffer.length());

      obuffer.rollback();

      EXPECT_EQ(0u, obuffer.length());
      EXPECT_EQ(16u, obuffer.available_space());
      Buffer::Page_list::iterator it = obuffer.pages().begin();
      for (; it != obuffer.pages().end(); ++it)
      {
        EXPECT_EQ(0u, (*it)->length);
      }
    }
  }
}