/*
 *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include <algorithm>
#include "webrtc/base/common.h"
#include "webrtc/base/httpcommon.h"
#include "webrtc/base/multipart.h"

namespace rtc {

///////////////////////////////////////////////////////////////////////////////
// MultipartStream
///////////////////////////////////////////////////////////////////////////////

MultipartStream::MultipartStream(const std::string& type,
                                 const std::string& boundary)
    : type_(type),
      boundary_(boundary),
      adding_(true),
      current_(0),
      position_(0) {
  // The content type should be multipart/*.
  ASSERT(0 == strncmp(type_.c_str(), "multipart/", 10));
}

MultipartStream::~MultipartStream() {
  Close();
}

void MultipartStream::GetContentType(std::string* content_type) {
  ASSERT(NULL != content_type);
  content_type->assign(type_);
  content_type->append("; boundary=");
  content_type->append(boundary_);
}

bool MultipartStream::AddPart(StreamInterface* data_stream,
                              const std::string& content_disposition,
                              const std::string& content_type) {
  if (!AddPart("", content_disposition, content_type))
    return false;
  parts_.push_back(data_stream);
  data_stream->SignalEvent.connect(this, &MultipartStream::OnEvent);
  return true;
}

bool MultipartStream::AddPart(const std::string& data,
                              const std::string& content_disposition,
                              const std::string& content_type) {
  ASSERT(adding_);
  if (!adding_)
    return false;
  std::stringstream ss;
  if (!parts_.empty()) {
    ss << "\r\n";
  }
  ss << "--" << boundary_ << "\r\n";
  if (!content_disposition.empty()) {
    ss << ToString(HH_CONTENT_DISPOSITION) << ": "
       << content_disposition << "\r\n";
  }
  if (!content_type.empty()) {
    ss << ToString(HH_CONTENT_TYPE) << ": "
       << content_type << "\r\n";
  }
  ss << "\r\n" << data;
  parts_.push_back(new MemoryStream(ss.str().data(), ss.str().size()));
  return true;
}

void MultipartStream::EndParts() {
  ASSERT(adding_);
  if (!adding_)
    return;

  std::stringstream ss;
  if (!parts_.empty()) {
    ss << "\r\n";
  }
  ss << "--" << boundary_ << "--" << "\r\n";
  parts_.push_back(new MemoryStream(ss.str().data(), ss.str().size()));

  ASSERT(0 == current_);
  ASSERT(0 == position_);
  adding_ = false;
  SignalEvent(this, SE_OPEN | SE_READ, 0);
}

size_t MultipartStream::GetPartSize(const std::string& data,
                                    const std::string& content_disposition,
                                    const std::string& content_type) const {
  size_t size = 0;
  if (!parts_.empty()) {
    size += 2;  // for "\r\n";
  }
  size += boundary_.size() + 4;  // for "--boundary_\r\n";
  if (!content_disposition.empty()) {
    // for ToString(HH_CONTENT_DISPOSITION): content_disposition\r\n
    size += std::string(ToString(HH_CONTENT_DISPOSITION)).size() + 2 +
        content_disposition.size() + 2;
  }
  if (!content_type.empty()) {
    // for ToString(HH_CONTENT_TYPE): content_type\r\n
    size += std::string(ToString(HH_CONTENT_TYPE)).size() + 2 +
        content_type.size() + 2;
  }
  size += 2 + data.size();  // for \r\ndata
  return size;
}

size_t MultipartStream::GetEndPartSize() const {
  size_t size = 0;
  if (!parts_.empty()) {
    size += 2;  // for "\r\n";
  }
  size += boundary_.size() + 6;  // for "--boundary_--\r\n";
  return size;
}

//
// StreamInterface
//

StreamState MultipartStream::GetState() const {
  if (adding_) {
    return SS_OPENING;
  }
  return (current_ < parts_.size()) ? SS_OPEN : SS_CLOSED;
}

StreamResult MultipartStream::Read(void* buffer, size_t buffer_len,
                                   size_t* read, int* error) {
  if (adding_) {
    return SR_BLOCK;
  }
  size_t local_read;
  if (!read) read = &local_read;
  while (current_ < parts_.size()) {
    StreamResult result = parts_[current_]->Read(buffer, buffer_len, read,
                                                 error);
    if (SR_EOS != result) {
      if (SR_SUCCESS == result) {
        position_ += *read;
      }
      return result;
    }
    ++current_;
  }
  return SR_EOS;
}

StreamResult MultipartStream::Write(const void* data, size_t data_len,
                                    size_t* written, int* error) {
  if (error) {
    *error = -1;
  }
  return SR_ERROR;
}

void MultipartStream::Close() {
  for (size_t i = 0; i < parts_.size(); ++i) {
    delete parts_[i];
  }
  parts_.clear();
  adding_ = false;
  current_ = 0;
  position_ = 0;
}

bool MultipartStream::SetPosition(size_t position) {
  if (adding_) {
    return false;
  }
  size_t part_size, part_offset = 0;
  for (size_t i = 0; i < parts_.size(); ++i) {
    if (!parts_[i]->GetSize(&part_size)) {
      return false;
    }
    if (part_offset + part_size > position) {
      for (size_t j = i + 1; j < std::min(parts_.size(), current_ + 1); ++j) {
        if (!parts_[j]->Rewind()) {
          return false;
        }
      }
      if (!parts_[i]->SetPosition(position - part_offset)) {
        return false;
      }
      current_ = i;
      position_ = position;
      return true;
    }
    part_offset += part_size;
  }
  return false;
}

bool MultipartStream::GetPosition(size_t* position) const {
  if (position) {
    *position = position_;
  }
  return true;
}

bool MultipartStream::GetSize(size_t* size) const {
  size_t part_size, total_size = 0;
  for (size_t i = 0; i < parts_.size(); ++i) {
    if (!parts_[i]->GetSize(&part_size)) {
      return false;
    }
    total_size += part_size;
  }
  if (size) {
    *size = total_size;
  }
  return true;
}

bool MultipartStream::GetAvailable(size_t* size) const {
  if (adding_) {
    return false;
  }
  size_t part_size, total_size = 0;
  for (size_t i = current_; i < parts_.size(); ++i) {
    if (!parts_[i]->GetAvailable(&part_size)) {
      return false;
    }
    total_size += part_size;
  }
  if (size) {
    *size = total_size;
  }
  return true;
}

//
// StreamInterface Slots
//

void MultipartStream::OnEvent(StreamInterface* stream, int events, int error) {
  if (adding_ || (current_ >= parts_.size()) || (parts_[current_] != stream)) {
    return;
  }
  SignalEvent(this, events, error);
}

}  // namespace rtc