text: /*-
   * Copyright 2021 Vsevolod Stakhov
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  #pragma once
  
  #ifndef RSPAMD_CSS_PROPERTY_HXX
  #define RSPAMD_CSS_PROPERTY_HXX
  
  #include <string>
  #include "css_tokeniser.hxx"
  #include "parse_error.hxx"
  #include "contrib/expected/expected.hpp"
  
  namespace rspamd::css {
  
  /*
   * To be extended with properties that are interesting from the email
   * point of view
   */
  enum class css_property_type : std::uint16_t {
  	PROPERTY_FONT = 0,
  	PROPERTY_FONT_COLOR,
  	PROPERTY_FONT_SIZE,
  	PROPERTY_COLOR,
  	PROPERTY_BGCOLOR,
  	PROPERTY_BACKGROUND,
  	PROPERTY_HEIGHT,
  	PROPERTY_WIDTH,
  	PROPERTY_DISPLAY,
  	PROPERTY_VISIBILITY,
  	PROPERTY_OPACITY,
  	PROPERTY_NYI,
  };
  
  enum class css_property_flag : std::uint16_t {
  	FLAG_NORMAL,
  	FLAG_IMPORTANT,
  	FLAG_NOT_IMPORTANT
  };
  
  struct alignas(int) css_property {
  	css_property_type type;
  	css_property_flag flag;
  
  	css_property(css_property_type t, css_property_flag fl = css_property_flag::FLAG_NORMAL) :
  			type(t), flag(fl) {}
  	static tl::expected<css_property,css_parse_error> from_token(
  			const css_parser_token &tok);
  
  	constexpr auto to_string(void) const -> const char * {
  		const char *ret = "nyi";
  
  		switch(type) {
  		case css_property_type::PROPERTY_FONT:
  			ret = "font";
  			break;
  		case css_property_type::PROPERTY_FONT_COLOR:
  			ret = "font-color";
  			break;
  		case css_property_type::PROPERTY_FONT_SIZE:
  			ret = "font-size";
  			break;
  		case css_property_type::PROPERTY_COLOR:
  			ret = "color";
  			break;
  		case css_property_type::PROPERTY_BGCOLOR:
  			ret = "bgcolor";
  			break;
  		case css_property_type::PROPERTY_BACKGROUND:
  			ret = "background";
  			break;
  		case css_property_type::PROPERTY_HEIGHT:
  			ret = "height";
  			break;
  		case css_property_type::PROPERTY_WIDTH:
  			ret = "width";
  			break;
  		case css_property_type::PROPERTY_DISPLAY:
  			ret = "display";
  			break;
  		case css_property_type::PROPERTY_VISIBILITY:
  			ret = "visibility";
  			break;
  		case css_property_type::PROPERTY_OPACITY:
  			ret = "opacity";
  			break;
  		default:
  			break;
  		}
  
  		return ret;
  	}
  
  	/* Helpers to define which values are valid for which properties */
  	auto is_color(void) const -> bool {
  		return type == css_property_type::PROPERTY_COLOR ||
  				type == css_property_type::PROPERTY_BACKGROUND ||
  				type == css_property_type::PROPERTY_BGCOLOR ||
  				type == css_property_type::PROPERTY_FONT_COLOR ||
  				type == css_property_type::PROPERTY_FONT;
  	}
  	auto is_dimension(void) const -> bool {
  		return type == css_property_type::PROPERTY_HEIGHT ||
  				type == css_property_type::PROPERTY_WIDTH ||
  				type == css_property_type::PROPERTY_FONT_SIZE ||
  				type == css_property_type::PROPERTY_FONT;
  	}
  
  	auto is_normal_number(void) const -> bool {
  		return type == css_property_type::PROPERTY_OPACITY;
  	}
  
  	auto is_display(void) const -> bool {
  		return type == css_property_type::PROPERTY_DISPLAY;
  	}
  
  	auto operator==(const css_property &other) const { return type == other.type; }
  };
  
  
  }
  
  /* Make properties hashable */
  namespace std {
  template<>
  class hash<rspamd::css::css_property> {
  public:
  	/* Mix bits to provide slightly better distribution but being constexpr */
  	constexpr size_t operator() (const rspamd::css::css_property &prop) const {
  		std::size_t key = 0xdeadbeef ^static_cast<std::size_t>(prop.type);
  		key = (~key) + (key << 21);
  		key = key ^ (key >> 24);
  		key = (key + (key << 3)) + (key << 8);
  		key = key ^ (key >> 14);
  		key = (key + (key << 2)) + (key << 4);
  		key = key ^ (key >> 28);
  		key = key + (key << 31);
  		return key;
  	}
  };
  }
  
  #endif //RSPAMD_CSS_PROPERTY_HXX