// 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 "chrome/browser/net/browser_url_util.h"

#include "base/string_util.h"
#include "base/utf_string_conversions.h"
#include "chrome/common/url_constants.h"
#include "googleurl/src/gurl.h"
#include "googleurl/src/url_parse.h"
#include "net/base/escape.h"
#include "net/base/net_util.h"
#include "ui/base/clipboard/scoped_clipboard_writer.h"

namespace chrome_browser_net {

void WriteURLToClipboard(const GURL& url,
                         const std::string& languages,
                         ui::Clipboard *clipboard) {
  if (url.is_empty() || !url.is_valid() || !clipboard)
    return;

  // Unescaping path and query is not a good idea because other applications
  // may not encode non-ASCII characters in UTF-8.  See crbug.com/2820.
  string16 text = url.SchemeIs(chrome::kMailToScheme) ?
      ASCIIToUTF16(url.path()) :
      net::FormatUrl(url, languages, net::kFormatUrlOmitNothing,
                     net::UnescapeRule::NONE, NULL, NULL, NULL);

  ui::ScopedClipboardWriter scw(clipboard, ui::Clipboard::BUFFER_STANDARD);
  scw.WriteURL(text);
}

GURL AppendQueryParameter(const GURL& url,
                          const std::string& name,
                          const std::string& value) {
  std::string query(url.query());

  if (!query.empty())
    query += "&";

  query += (net::EscapeQueryParamValue(name, true) + "=" +
            net::EscapeQueryParamValue(value, true));
  GURL::Replacements replacements;
  replacements.SetQueryStr(query);
  return url.ReplaceComponents(replacements);
}


GURL AppendOrReplaceQueryParameter(const GURL& url,
                                   const std::string& name,
                                   const std::string& value) {
  bool replaced = false;
  std::string param_name = net::EscapeQueryParamValue(name, true);
  std::string param_value = net::EscapeQueryParamValue(value, true);

  const std::string input = url.query();
  url_parse::Component cursor(0, input.size());
  std::string output;
  url_parse::Component key_range, value_range;
  while (url_parse::ExtractQueryKeyValue(
             input.data(), &cursor, &key_range, &value_range)) {
    const base::StringPiece key(
        input.data() + key_range.begin, key_range.len);
    const base::StringPiece value(
        input.data() + value_range.begin, value_range.len);
    std::string key_value_pair;
    // Check |replaced| as only the first pair should be replaced.
    if (!replaced && key == param_name) {
      replaced = true;
      key_value_pair = (param_name + "=" + param_value);
    } else {
      key_value_pair.assign(input.data(),
                            key_range.begin,
                            value_range.end() - key_range.begin);
    }
    if (!output.empty())
      output += "&";

    output += key_value_pair;
  }
  if (!replaced) {
    if (!output.empty())
      output += "&";

    output += (param_name + "=" + param_value);
  }
  GURL::Replacements replacements;
  replacements.SetQueryStr(output);
  return url.ReplaceComponents(replacements);
}

}  // namespace chrome_browser_net