/*
 * Copyright (C) 2017 Mentor Graphics Development (Deutschland) GmbH
 *
 * 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.
 */

#ifndef TMCAGLWM_LAYERS_H
#define TMCAGLWM_LAYERS_H

#include <json.hpp>
#include <set>
#include <string>

#include "result.hpp"
#include "wayland.hpp"

namespace wm {

struct layer {
   using json = nlohmann::json;

   // Min and max surface ID mapped to this layer
   int id_min = -1;
   int id_max = -1;
   // A more or less descriptive name?
   std::string name = "";
   // The actual layer ID
   int layer_id = -1;
   // The rectangular region surfaces are allowed to draw on
   // this layer, note however, width and hieght of the rect
   // can be negative, in which case they specify that
   // the actual value is computed using MAX + 1 - w
   // That is; allow us to specify dimensions dependent on
   // e.g. screen dimension, w/o knowing the actual screen size.
   genivi::rect rect;
   // Specify a role prefix for surfaces that should be
   // put on this layer.
   std::string role;
   // XXX perhaps a zorder is needed here?

   explicit layer(nlohmann::json const &j);

   bool operator<(struct layer const &rhs) const {
      return this->id_max < rhs.id_max;
   }

   json to_json() const;
};

struct layer_map {
   using json = nlohmann::json;

   typedef std::set<struct layer> storage_type;
   typedef std::vector<unsigned int> layers_type;
   typedef std::vector<std::pair<std::string, int>> role_to_layer_map;
   typedef std::map<unsigned, unsigned> addsurf_layer_map;

   // XXX: we also will need a layer_id to layer map, perhaps
   // make this the primary map, and the surface_id->layer a
   // secondary map.

   storage_type mapping;  // map surface_id to layer
   layers_type layers;    // the actual layer IDs we have
   int main_surface;
   std::string main_surface_name;
   role_to_layer_map roles;
   addsurf_layer_map surfaces;  // additional surfaces on layers

   optional<int> get_layer_id(int surface_id);
   optional<int> get_layer_id(std::string const &role);
   optional<struct layer> get_layer(int layer_id) {
      auto i = std::find_if(
         std::cbegin(this->mapping), std::cend(this->mapping),
         [layer_id](struct layer const &l) { return layer_id == l.layer_id; });
      return i == this->mapping.end() ? nullopt : optional<struct layer>(*i);
   }

   optional<genivi::rect> get_layer_rect(int surface_id);
   layers_type::size_type get_layers_count() const {
      return this->layers.size();
   }

   void add_surface(unsigned surface_id, unsigned layer_id) {
      this->surfaces[surface_id] = layer_id;
   }

   json to_json() const;
};

struct result<struct layer_map> to_layer_map(nlohmann::json const &j);

}  // namespace wm

#endif  // TMCAGLWM_LAYERS_H