/*
 * 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.
 */

#include <algorithm>
#include <regex>

#include "json_helper.hpp"
#include "layers.hpp"
#include "util.hpp"

namespace wm {

using json = nlohmann::json;

layer::layer(nlohmann::json const &j) {
   this->role = j["role"];
   this->name = j["name"];
   this->layer_id = j["layer_id"];
   this->rect = genivi::full_rect;
   if (j["area"]["type"] == "rect") {
      auto jr = j["area"]["rect"];
      this->rect = genivi::rect{
         jr["width"], jr["height"], jr["x"], jr["y"],
      };
   }
   auto split_layouts = j.find("split_layouts");
   if (split_layouts != j.end()) {
      auto &sls = j["split_layouts"];
      // this->layouts.reserve(sls.size());
      std::transform(std::cbegin(sls), std::cend(sls),
                     std::back_inserter(this->layouts), [this](json const &sl) {
                        struct split_layout l {
                           sl["name"], sl["main_match"], sl["sub_match"] };
                        logdebug(
                           "layer %d add split_layout \"%s\" (main: \"%s\") (sub: "
                           "\"%s\")", this->layer_id,
                           l.name.c_str(), l.main_match.c_str(),
                           l.sub_match.c_str());
                        return l;
                     });
   }
}

struct result<struct layer_map> to_layer_map(nlohmann::json const &j) {
   try {
      layer_map stl{};
      auto m = j["mappings"];

      std::transform(std::cbegin(m), std::cend(m),
                     std::inserter(stl.mapping, stl.mapping.end()),
                     [](nlohmann::json const &j) {
                        return std::pair<int, struct layer>(
                           j.value("layer_id", -1), layer(j));
                     });

      // XXX: add sanity checks here?
      // * check for double IDs
      // * check for double names/roles

      stl.layers.reserve(m.size());
      std::transform(std::cbegin(stl.mapping), std::cend(stl.mapping),
                     std::back_inserter(stl.layers),
                     [&stl](std::pair<int, struct layer> const &k) {
                        stl.roles.emplace_back(
                           std::make_pair(k.second.role, k.second.layer_id));
                        return unsigned(k.second.layer_id);
                     });

      std::sort(stl.layers.begin(), stl.layers.end());

      for (auto i : stl.mapping) {
         if (i.second.name.empty()) {
            return Err<struct layer_map>("Found mapping w/o name");
         }
         if (i.second.layer_id == -1) {
            return Err<struct layer_map>("Found invalid/unset IDs in mapping");
         }
      }

      auto msi = j.find("main_surface");
      if (msi != j.end()) {
         stl.main_surface_name = msi->value("surface_role", "");
         stl.main_surface = -1;
      }

      return Ok(stl);
   } catch (std::exception &e) {
      return Err<struct layer_map>(e.what());
   }
}

optional<int> layer_map::get_layer_id(int surface_id) {
   auto i = this->surfaces.find(surface_id);
   if (i != this->surfaces.end()) {
      return optional<int>(i->second);
   }
   return nullopt;
}

optional<int> layer_map::get_layer_id(std::string const &role) {
   for (auto const &r : this->roles) {
      auto re = std::regex(r.first);
      if (std::regex_match(role, re)) {
         logdebug("role %s matches layer %d", role.c_str(), r.second);
         return optional<int>(r.second);
      }
   }
   logdebug("role %s does NOT match any layer", role.c_str());
   return nullopt;
}

json layer::to_json() const {
   auto is_full = this->rect == genivi::full_rect;

   json r{};
   if (is_full) {
      r = {{"type", "full"}};
   } else {
      r = {{"type", "rect"},
           {"rect",
            {{"x", this->rect.x},
             {"y", this->rect.y},
             {"width", this->rect.w},
             {"height", this->rect.h}}}};
   }

   return {
      {"name", this->name},         {"role", this->role},
      {"layer_id", this->layer_id}, {"area", r},
   };
}

json layer_map::to_json() const {
   json j{};
   for (auto const &i : this->mapping) {
      j.push_back(i.second.to_json());
   }
   return j;
}

}  // namespace wm