// 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.

#ifndef NET_PROXY_PROXY_BYPASS_RULES_H_
#define NET_PROXY_PROXY_BYPASS_RULES_H_

#include <string>
#include <vector>

#include "base/ref_counted.h"
#include "googleurl/src/gurl.h"

namespace net {

// ProxyBypassRules describes the set of URLs that should bypass the proxy
// settings, as a list of rules. A URL is said to match the bypass rules
// if it matches any one of these rules.
class ProxyBypassRules {
 public:
  // Interface for an individual proxy bypass rule.
  class Rule : public base::RefCounted<Rule> {
   public:
    Rule() {}
    virtual ~Rule() {}

    // Returns true if |url| matches the rule.
    virtual bool Matches(const GURL& url) const = 0;

    // Returns a string representation of this rule. This is used both for
    // visualizing the rules, and also to test equality of a rules list.
    virtual std::string ToString() const = 0;

    bool Equals(const Rule& rule) const {
      return ToString() == rule.ToString();
    }

   private:
    DISALLOW_COPY_AND_ASSIGN(Rule);
  };

  typedef std::vector<scoped_refptr<Rule> > RuleList;

  // Note: This class supports copy constructor and assignment.

  ~ProxyBypassRules();

  // Returns the current list of rules.
  const RuleList& rules() const { return rules_; }

  // Returns true if |url| matches any of the proxy bypass rules.
  bool Matches(const GURL& url) const;

  // Returns true if |*this| is equal to |other|; in other words, whether they
  // describe the same set of rules.
  bool Equals(const ProxyBypassRules& other) const;

  // Initializes the list of rules by parsing the string |raw|. |raw| is a
  // comma separated list of rules. See AddRuleFromString() to see the list
  // of supported formats.
  void ParseFromString(const std::string& raw);

  // This is a variant of ParseFromString, which interprets hostname patterns
  // as suffix tests rather than hostname tests (so "google.com" would actually
  // match "*google.com"). This is only currently used for the linux no_proxy
  // evironment variable. It is less flexible, since with the suffix matching
  // format you can't match an individual host.
  // NOTE: Use ParseFromString() unless you truly need this behavior.
  void ParseFromStringUsingSuffixMatching(const std::string& raw);

  // Adds a rule that matches a URL when all of the following are true:
  //  (a) The URL's scheme matches |optional_scheme|, if
  //      |!optional_scheme.empty()|
  //  (b) The URL's hostname matches |hostname_pattern|.
  //  (c) The URL's (effective) port number matches |optional_port| if
  //      |optional_port != -1|
  // Returns true if the rule was successfully added.
  bool AddRuleForHostname(const std::string& optional_scheme,
                          const std::string& hostname_pattern,
                          int optional_port);

  // Adds a rule that bypasses all "local" hostnames.
  // This matches IE's interpretation of the
  // "Bypass proxy server for local addresses" settings checkbox. Fully
  // qualified domain names or IP addresses are considered non-local,
  // regardless of what they map to (except for the loopback addresses).
  void AddRuleToBypassLocal();

  // Adds a rule given by the string |raw|. The format of |raw| can be any of
  // the following:
  //
  //   [ <scheme> "://" ] <hostname_pattern> [ ":" <port> ]
  //   "." <hostname_suffix_pattern> [ ":" <port> ]
  //   [ <scheme> "://" ] <ip_literal> [ ":" <port> ]
  //   "<local>"
  //
  // Note that <ip_literal> can be either an IPv4 literal, or an IPv6 literal
  // but if it is an IPv6 literal it MUST be surrounded by square brackets,
  // as in "[::1]".
  //
  // Also note that "<local>" means to bypass all local hostnames. (See
  // AddRuleToBypassLocal() for details).
  //
  // Returns true if the rule was successfully added.
  //
  // TODO(eroman): support IPv6 literals without brackets.
  // TODO(eroman): support CIDR-style IP masks. (http://crbug.com/9835).
  //
  bool AddRuleFromString(const std::string& raw);

  // Removes all the rules.
  void Clear();

 private:
  // The following are variants of ParseFromString() and AddRuleFromString(),
  // which additionally prefix hostname patterns with a wildcard if
  // |use_hostname_suffix_matching| was true.
  void ParseFromStringInternal(const std::string& raw,
                               bool use_hostname_suffix_matching);
  bool AddRuleFromStringInternal(const std::string& raw,
                                 bool use_hostname_suffix_matching);
  bool AddRuleFromStringInternalWithLogging(const std::string& raw,
                                            bool use_hostname_suffix_matching);

  RuleList rules_;
};

}  // namespace net

#endif  // NET_PROXY_PROXY_BYPASS_RULES_H_