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

#ifndef EXTENSIONS_BROWSER_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_CONDITION_ATTRIBUTE_H_
#define EXTENSIONS_BROWSER_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_CONDITION_ATTRIBUTE_H_

#include <stdint.h>
#include <memory>
#include <string>
#include <vector>

#include "base/memory/ref_counted.h"
#include "extensions/browser/api/declarative_webrequest/request_stage.h"
#include "extensions/common/api/events.h"

namespace base {
class Value;
}

namespace extensions {

enum class WebRequestResourceType : uint8_t;

class HeaderMatcher;
struct WebRequestData;

// Base class for all condition attributes of the declarative Web Request API
// except for condition attribute to test URLPatterns.
class WebRequestConditionAttribute
    : public base::RefCounted<WebRequestConditionAttribute> {
 public:
  enum Type {
    CONDITION_RESOURCE_TYPE = 0,
    CONDITION_CONTENT_TYPE = 1,
    CONDITION_RESPONSE_HEADERS = 2,
    CONDITION_REQUEST_HEADERS = 3,
    CONDITION_STAGES = 4,
  };

  WebRequestConditionAttribute();

  WebRequestConditionAttribute(const WebRequestConditionAttribute&) = delete;
  WebRequestConditionAttribute& operator=(const WebRequestConditionAttribute&) =
      delete;

  // Factory method that creates a WebRequestConditionAttribute for the JSON
  // dictionary {`name`: `value`} passed by the extension API. Sets `error` and
  // returns NULL if something fails.
  // The ownership of `value` remains at the caller.
  static scoped_refptr<const WebRequestConditionAttribute> Create(
      const std::string& name,
      const base::Value* value,
      std::string* error);

  // Returns a bit vector representing extensions::RequestStage. The bit vector
  // contains a 1 for each request stage during which the condition attribute
  // can be tested.
  virtual int GetStages() const = 0;

  // Returns whether the condition is fulfilled for this request.
  virtual bool IsFulfilled(
      const WebRequestData& request_data) const = 0;

  virtual Type GetType() const = 0;
  virtual std::string GetName() const = 0;

  // Compares the Type of two WebRequestConditionAttributes, needs to be
  // overridden for parameterized types.
  virtual bool Equals(const WebRequestConditionAttribute* other) const;

 protected:
  friend class base::RefCounted<WebRequestConditionAttribute>;
  virtual ~WebRequestConditionAttribute();
};

typedef std::vector<scoped_refptr<const WebRequestConditionAttribute> >
    WebRequestConditionAttributes;

//
// The following are concrete condition attributes.
//

// Condition that checks whether a request is for a specific resource type.
class WebRequestConditionAttributeResourceType
    : public WebRequestConditionAttribute {
 public:
  WebRequestConditionAttributeResourceType(
      const WebRequestConditionAttributeResourceType&) = delete;
  WebRequestConditionAttributeResourceType& operator=(
      const WebRequestConditionAttributeResourceType&) = delete;

  // Factory method, see WebRequestConditionAttribute::Create.
  static scoped_refptr<const WebRequestConditionAttribute> Create(
      const std::string& instance_type,
      const base::Value* value,
      std::string* error,
      bool* bad_message);

  // Implementation of WebRequestConditionAttribute:
  int GetStages() const override;
  bool IsFulfilled(const WebRequestData& request_data) const override;
  Type GetType() const override;
  std::string GetName() const override;
  bool Equals(const WebRequestConditionAttribute* other) const override;

 private:
  explicit WebRequestConditionAttributeResourceType(
      const std::vector<WebRequestResourceType>& types);
  ~WebRequestConditionAttributeResourceType() override;

  // TODO(pkalinnikov): Make this a bitmask.
  const std::vector<WebRequestResourceType> types_;
};

// Condition that checks whether a response's Content-Type header has a
// certain MIME media type.
class WebRequestConditionAttributeContentType
    : public WebRequestConditionAttribute {
 public:
  WebRequestConditionAttributeContentType(
      const WebRequestConditionAttributeContentType&) = delete;
  WebRequestConditionAttributeContentType& operator=(
      const WebRequestConditionAttributeContentType&) = delete;

  // Factory method, see WebRequestConditionAttribute::Create.
  static scoped_refptr<const WebRequestConditionAttribute> Create(
      const std::string& name,
      const base::Value* value,
      std::string* error,
      bool* bad_message);

  // Implementation of WebRequestConditionAttribute:
  int GetStages() const override;
  bool IsFulfilled(const WebRequestData& request_data) const override;
  Type GetType() const override;
  std::string GetName() const override;
  bool Equals(const WebRequestConditionAttribute* other) const override;

 private:
  explicit WebRequestConditionAttributeContentType(
      const std::vector<std::string>& include_content_types,
      bool inclusive);
  ~WebRequestConditionAttributeContentType() override;

  const std::vector<std::string> content_types_;
  const bool inclusive_;
};

// Condition attribute for matching against request headers. Uses HeaderMatcher
// to handle the actual tests, in connection with a boolean positiveness
// flag. If that flag is set to true, then IsFulfilled() returns true iff
// `header_matcher_` matches at least one header. Otherwise IsFulfilled()
// returns true iff the `header_matcher_` matches no header.
class WebRequestConditionAttributeRequestHeaders
    : public WebRequestConditionAttribute {
 public:
  WebRequestConditionAttributeRequestHeaders(
      const WebRequestConditionAttributeRequestHeaders&) = delete;
  WebRequestConditionAttributeRequestHeaders& operator=(
      const WebRequestConditionAttributeRequestHeaders&) = delete;

  // Factory method, see WebRequestConditionAttribute::Create.
  static scoped_refptr<const WebRequestConditionAttribute> Create(
      const std::string& name,
      const base::Value* value,
      std::string* error,
      bool* bad_message);

  // Implementation of WebRequestConditionAttribute:
  int GetStages() const override;
  bool IsFulfilled(const WebRequestData& request_data) const override;
  Type GetType() const override;
  std::string GetName() const override;
  bool Equals(const WebRequestConditionAttribute* other) const override;

 private:
  WebRequestConditionAttributeRequestHeaders(
      std::unique_ptr<const HeaderMatcher> header_matcher,
      bool positive);
  ~WebRequestConditionAttributeRequestHeaders() override;

  const std::unique_ptr<const HeaderMatcher> header_matcher_;
  const bool positive_;
};

// Condition attribute for matching against response headers. Uses HeaderMatcher
// to handle the actual tests, in connection with a boolean positiveness
// flag. If that flag is set to true, then IsFulfilled() returns true iff
// `header_matcher_` matches at least one header. Otherwise IsFulfilled()
// returns true iff the `header_matcher_` matches no header.
class WebRequestConditionAttributeResponseHeaders
    : public WebRequestConditionAttribute {
 public:
  WebRequestConditionAttributeResponseHeaders(
      const WebRequestConditionAttributeResponseHeaders&) = delete;
  WebRequestConditionAttributeResponseHeaders& operator=(
      const WebRequestConditionAttributeResponseHeaders&) = delete;

  // Factory method, see WebRequestConditionAttribute::Create.
  static scoped_refptr<const WebRequestConditionAttribute> Create(
      const std::string& name,
      const base::Value* value,
      std::string* error,
      bool* bad_message);

  // Implementation of WebRequestConditionAttribute:
  int GetStages() const override;
  bool IsFulfilled(const WebRequestData& request_data) const override;
  Type GetType() const override;
  std::string GetName() const override;
  bool Equals(const WebRequestConditionAttribute* other) const override;

 private:
  WebRequestConditionAttributeResponseHeaders(
      std::unique_ptr<const HeaderMatcher> header_matcher,
      bool positive);
  ~WebRequestConditionAttributeResponseHeaders() override;

  const std::unique_ptr<const HeaderMatcher> header_matcher_;
  const bool positive_;
};

// This condition is used as a filter for request stages. It is true exactly in
// stages specified on construction.
class WebRequestConditionAttributeStages
    : public WebRequestConditionAttribute {
 public:
  WebRequestConditionAttributeStages(
      const WebRequestConditionAttributeStages&) = delete;
  WebRequestConditionAttributeStages& operator=(
      const WebRequestConditionAttributeStages&) = delete;

  // Factory method, see WebRequestConditionAttribute::Create.
  static scoped_refptr<const WebRequestConditionAttribute> Create(
      const std::string& name,
      const base::Value* value,
      std::string* error,
      bool* bad_message);

  // Implementation of WebRequestConditionAttribute:
  int GetStages() const override;
  bool IsFulfilled(const WebRequestData& request_data) const override;
  Type GetType() const override;
  std::string GetName() const override;
  bool Equals(const WebRequestConditionAttribute* other) const override;

 private:
  explicit WebRequestConditionAttributeStages(int allowed_stages);
  ~WebRequestConditionAttributeStages() override;

  const int allowed_stages_;  // Composition of RequestStage values.
};

}  // namespace extensions

#endif  // EXTENSIONS_BROWSER_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_CONDITION_ATTRIBUTE_H_