// Copyright (c) 2010 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/proxy/proxy_config.h"

#include <sstream>

#include "base/logging.h"
#include "base/string_number_conversions.h"
#include "base/string_tokenizer.h"
#include "base/string_util.h"
#include "base/values.h"
#include "net/proxy/proxy_info.h"

namespace net {

namespace {

// Helper to stringize a ProxyServer.
std::ostream& operator<<(std::ostream& out,
                         const ProxyServer& proxy_server) {
  if (proxy_server.is_valid())
    out << proxy_server.ToURI();
  return out;
}

const char* BoolToYesNoString(bool b) {
  return b ? "Yes" : "No";
}

std::ostream& operator<<(std::ostream& out,
                         const ProxyConfig::ProxyRules& rules) {
  // Stringize the type enum.
  std::string type;
  switch (rules.type) {
    case net::ProxyConfig::ProxyRules::TYPE_NO_RULES:
      type = "TYPE_NO_RULES";
      break;
    case net::ProxyConfig::ProxyRules::TYPE_PROXY_PER_SCHEME:
      type = "TYPE_PROXY_PER_SCHEME";
      break;
    case net::ProxyConfig::ProxyRules::TYPE_SINGLE_PROXY:
      type = "TYPE_SINGLE_PROXY";
      break;
    default:
      type = base::IntToString(rules.type);
      break;
  }
  return out << "  {\n"
             << "    type: " << type << "\n"
             << "    single_proxy: " << rules.single_proxy << "\n"
             << "    proxy_for_http: " << rules.proxy_for_http << "\n"
             << "    proxy_for_https: " << rules.proxy_for_https << "\n"
             << "    proxy_for_ftp: " << rules.proxy_for_ftp << "\n"
             << "    fallback_proxy: " << rules.fallback_proxy << "\n"
             << "  }";
}

std::ostream& operator<<(std::ostream& out, const ProxyConfig& config) {
  // "Automatic" settings.
  out << "Automatic settings:\n";
  out << "  Auto-detect: " << BoolToYesNoString(config.auto_detect()) << "\n";
  out << "  Custom PAC script: ";
  if (config.has_pac_url())
    out << config.pac_url();
  else
    out << "[None]";
  out << "\n";

  // "Manual" settings.
  out << "Manual settings:\n";
  out << "  Proxy server: ";

  switch (config.proxy_rules().type) {
    case net::ProxyConfig::ProxyRules::TYPE_NO_RULES:
      out << "[None]\n";
      break;
    case net::ProxyConfig::ProxyRules::TYPE_SINGLE_PROXY:
      out << config.proxy_rules().single_proxy;
      out << "\n";
      break;
    case net::ProxyConfig::ProxyRules::TYPE_PROXY_PER_SCHEME:
      out << "\n";
      if (config.proxy_rules().proxy_for_http.is_valid())
        out << "    HTTP: " << config.proxy_rules().proxy_for_http << "\n";
      if (config.proxy_rules().proxy_for_https.is_valid())
        out << "    HTTPS: " << config.proxy_rules().proxy_for_https << "\n";
      if (config.proxy_rules().proxy_for_ftp.is_valid())
        out << "    FTP: " << config.proxy_rules().proxy_for_ftp << "\n";
      if (config.proxy_rules().fallback_proxy.is_valid()) {
        out << "    (fallback): "
            << config.proxy_rules().fallback_proxy << "\n";
      }
      break;
  }

  if (config.proxy_rules().reverse_bypass)
    out << "  Only use proxy for: ";
  else
    out << "  Bypass list: ";
  if (config.proxy_rules().bypass_rules.rules().empty()) {
    out << "[None]";
  } else {
    const net::ProxyBypassRules& bypass_rules =
        config.proxy_rules().bypass_rules;
    net::ProxyBypassRules::RuleList::const_iterator it;
    for (it = bypass_rules.rules().begin();
         it != bypass_rules.rules().end(); ++it) {
      out << "\n    " << (*it)->ToString();
    }
  }

  return out;
}

std::string ProxyConfigToString(const ProxyConfig& proxy_config) {
  std::ostringstream stream;
  stream << proxy_config;
  return stream.str();
}

}  // namespace

bool ProxyConfig::ProxyRules::Equals(const ProxyRules& other) const {
  return type == other.type &&
         single_proxy == other.single_proxy &&
         proxy_for_http == other.proxy_for_http &&
         proxy_for_https == other.proxy_for_https &&
         proxy_for_ftp == other.proxy_for_ftp &&
         fallback_proxy == other.fallback_proxy &&
         bypass_rules.Equals(other.bypass_rules) &&
         reverse_bypass == other.reverse_bypass;
}

void ProxyConfig::ProxyRules::Apply(const GURL& url, ProxyInfo* result) {
  if (empty()) {
    result->UseDirect();
    return;
  }

  bool bypass_proxy = bypass_rules.Matches(url);
  if (reverse_bypass)
    bypass_proxy = !bypass_proxy;
  if (bypass_proxy) {
    result->UseDirect();
    return;
  }

  switch (type) {
    case ProxyRules::TYPE_SINGLE_PROXY: {
      result->UseProxyServer(single_proxy);
      return;
    }
    case ProxyRules::TYPE_PROXY_PER_SCHEME: {
      const ProxyServer* entry = MapUrlSchemeToProxy(url.scheme());
      if (entry) {
        result->UseProxyServer(*entry);
      } else {
        // We failed to find a matching proxy server for the current URL
        // scheme. Default to direct.
        result->UseDirect();
      }
      return;
    }
    default: {
      result->UseDirect();
      NOTREACHED();
      return;
    }
  }
}

void ProxyConfig::ProxyRules::ParseFromString(const std::string& proxy_rules) {
  // Reset.
  type = TYPE_NO_RULES;
  single_proxy = ProxyServer();
  proxy_for_http = ProxyServer();
  proxy_for_https = ProxyServer();
  proxy_for_ftp = ProxyServer();
  fallback_proxy = ProxyServer();

  StringTokenizer proxy_server_list(proxy_rules, ";");
  while (proxy_server_list.GetNext()) {
    StringTokenizer proxy_server_for_scheme(
        proxy_server_list.token_begin(), proxy_server_list.token_end(), "=");

    while (proxy_server_for_scheme.GetNext()) {
      std::string url_scheme = proxy_server_for_scheme.token();

      // If we fail to get the proxy server here, it means that
      // this is a regular proxy server configuration, i.e. proxies
      // are not configured per protocol.
      if (!proxy_server_for_scheme.GetNext()) {
        if (type == TYPE_PROXY_PER_SCHEME)
          continue;  // Unexpected.
        single_proxy = ProxyServer::FromURI(url_scheme,
                                            ProxyServer::SCHEME_HTTP);
        type = TYPE_SINGLE_PROXY;
        return;
      }

      // Trim whitespace off the url scheme.
      TrimWhitespaceASCII(url_scheme, TRIM_ALL, &url_scheme);

      // Add it to the per-scheme mappings (if supported scheme).
      type = TYPE_PROXY_PER_SCHEME;
      ProxyServer* entry = MapUrlSchemeToProxyNoFallback(url_scheme);
      ProxyServer::Scheme default_scheme = ProxyServer::SCHEME_HTTP;

      // socks=XXX is inconsistent with the other formats, since "socks"
      // is not a URL scheme. Rather this means "for everything else, send
      // it to the SOCKS proxy server XXX".
      if (url_scheme == "socks") {
        DCHECK(!entry);
        entry = &fallback_proxy;
        default_scheme = ProxyServer::SCHEME_SOCKS4;
      }

      if (entry) {
        *entry = ProxyServer::FromURI(proxy_server_for_scheme.token(),
                                      default_scheme);
      }
    }
  }
}

const ProxyServer* ProxyConfig::ProxyRules::MapUrlSchemeToProxy(
    const std::string& url_scheme) const {
  const ProxyServer* proxy_server =
      const_cast<ProxyRules*>(this)->MapUrlSchemeToProxyNoFallback(url_scheme);
  if (proxy_server && proxy_server->is_valid())
    return proxy_server;
  if (fallback_proxy.is_valid())
    return &fallback_proxy;
  return NULL;  // No mapping for this scheme. Use direct.
}

ProxyServer* ProxyConfig::ProxyRules::MapUrlSchemeToProxyNoFallback(
    const std::string& scheme) {
  DCHECK_EQ(TYPE_PROXY_PER_SCHEME, type);
  if (scheme == "http")
    return &proxy_for_http;
  if (scheme == "https")
    return &proxy_for_https;
  if (scheme == "ftp")
    return &proxy_for_ftp;
  return NULL;  // No mapping for this scheme.
}

ProxyConfig::ProxyConfig() : auto_detect_(false), id_(INVALID_ID) {
}

bool ProxyConfig::Equals(const ProxyConfig& other) const {
  // The two configs can have different IDs.  We are just interested in if they
  // have the same settings.
  return auto_detect_ == other.auto_detect_ &&
         pac_url_ == other.pac_url_ &&
         proxy_rules_.Equals(other.proxy_rules());
}

bool ProxyConfig::MayRequirePACResolver() const {
  return auto_detect_ || has_pac_url();
}

std::string ProxyConfig::ToString() const {
  return ProxyConfigToString(*this);
}

Value* ProxyConfig::ToValue() const {
  // TODO(eroman): send a dictionary rather than a flat string, so the
  //               javascript client can do prettier formatting.
  //               crbug.com/52011
  return Value::CreateStringValue(ToString());
}

}  // namespace net