// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/url_request/url_request_simple_job.h"

#include <vector>

#include "base/bind.h"
#include "base/compiler_specific.h"
#include "base/message_loop/message_loop.h"
#include "net/base/io_buffer.h"
#include "net/base/net_errors.h"
#include "net/http/http_request_headers.h"
#include "net/http/http_util.h"
#include "net/url_request/url_request_status.h"

namespace net {

URLRequestSimpleJob::URLRequestSimpleJob(
    URLRequest* request, NetworkDelegate* network_delegate)
    : URLRangeRequestJob(request, network_delegate),
      data_offset_(0),
      weak_factory_(this) {}

void URLRequestSimpleJob::Start() {
  // Start reading asynchronously so that all error reporting and data
  // callbacks happen as they would for network requests.
  base::MessageLoop::current()->PostTask(
      FROM_HERE,
      base::Bind(&URLRequestSimpleJob::StartAsync, weak_factory_.GetWeakPtr()));
}

bool URLRequestSimpleJob::GetMimeType(std::string* mime_type) const {
  *mime_type = mime_type_;
  return true;
}

bool URLRequestSimpleJob::GetCharset(std::string* charset) {
  *charset = charset_;
  return true;
}

URLRequestSimpleJob::~URLRequestSimpleJob() {}

bool URLRequestSimpleJob::ReadRawData(IOBuffer* buf, int buf_size,
                                      int* bytes_read) {
  DCHECK(bytes_read);
  int remaining = byte_range_.last_byte_position() - data_offset_ + 1;
  if (buf_size > remaining)
    buf_size = remaining;
  memcpy(buf->data(), data_.data() + data_offset_, buf_size);
  data_offset_ += buf_size;
  *bytes_read = buf_size;
  return true;
}

void URLRequestSimpleJob::StartAsync() {
  if (!request_)
    return;

  if (ranges().size() > 1) {
    NotifyDone(URLRequestStatus(URLRequestStatus::FAILED,
                                ERR_REQUEST_RANGE_NOT_SATISFIABLE));
    return;
  }

  if (!ranges().empty() && range_parse_result() == OK)
    byte_range_ = ranges().front();

  int result = GetData(&mime_type_, &charset_, &data_,
                       base::Bind(&URLRequestSimpleJob::OnGetDataCompleted,
                                  weak_factory_.GetWeakPtr()));
  if (result != ERR_IO_PENDING)
    OnGetDataCompleted(result);
}

void URLRequestSimpleJob::OnGetDataCompleted(int result) {
  if (result == OK) {
    // Notify that the headers are complete
    if (!byte_range_.ComputeBounds(data_.size())) {
      NotifyDone(URLRequestStatus(URLRequestStatus::FAILED,
                 ERR_REQUEST_RANGE_NOT_SATISFIABLE));
      return;
    }

    data_offset_ = byte_range_.first_byte_position();
    int remaining_bytes = byte_range_.last_byte_position() -
        byte_range_.first_byte_position() + 1;
    set_expected_content_size(remaining_bytes);
    NotifyHeadersComplete();
  } else {
    NotifyStartError(URLRequestStatus(URLRequestStatus::FAILED, result));
  }
}

}  // namespace net