#include <google/protobuf/message.h>
#include <google/protobuf/text_format.h>

#include <cstdint>
#include <fstream>
#include <iostream>
#include <map>
#include <sstream>
#include <string>

#include "proto/human.pb.h"

namespace com::fourisland::lingo2_archipelago {
namespace {

template <typename T>
T ReadMessageFromFile(const std::string& path) {
  std::cout << "Processing " << path << std::endl;

  std::ifstream file(path);
  std::stringstream buffer;
  buffer << file.rdbuf();

  T message;
  google::protobuf::TextFormat::ParseFromString(buffer.str(), &message);

  return message;
}

class AssignIds {
 public:
  AssignIds(const std::string& mapdir) : mapdir_(mapdir) {}

  void Run() {
    std::filesystem::path datadir_path = mapdir_;
    std::filesystem::path ids_path = datadir_path / "ids.txtpb";

    ReadIds(ids_path);

    ProcessMaps(datadir_path);

    WriteIds(ids_path);

    std::cout << "Next ID: " << next_id_ << std::endl;
  }

  void ReadIds(std::filesystem::path path) {
    id_mappings_ = ReadMessageFromFile<IdMappings>(path.string());

    for (const auto& [_, map] : id_mappings_.maps()) {
      for (const auto& [_, id] : map.doors()) {
        if (id > next_id_) {
          next_id_ = id;
        }
      }

      for (const auto& [_, room] : map.rooms()) {
        for (const auto& [_, id] : room.panels()) {
          if (id > next_id_) {
            next_id_ = id;
          }
        }
      }
    }

    for (const auto& [_, id] : id_mappings_.special()) {
      if (id > next_id_) {
        next_id_ = id;
      }
    }

    next_id_++;
  }

  void WriteIds(std::filesystem::path path) {
    std::string output;
    google::protobuf::TextFormat::PrintToString(id_mappings_, &output);

    {
      std::ofstream outputfile(path.string());
      outputfile << output;
    }
  }

  void ProcessMaps(std::filesystem::path path) {
    std::filesystem::path maps_dir = path / "maps";
    for (auto const& dir_entry :
         std::filesystem::directory_iterator(maps_dir)) {
      ProcessMap(dir_entry.path());
    }
  }

  void ProcessMap(std::filesystem::path path) {
    std::string map_name = path.filename();

    ProcessDoorsFile(path / "doors.txtpb", map_name);
    ProcessRooms(path / "rooms", map_name);
  }

  void ProcessDoorsFile(std::filesystem::path path,
                        const std::string& current_map_name) {
    if (!std::filesystem::exists(path)) {
      return;
    }

    auto doors = ReadMessageFromFile<HumanDoors>(path.string());

    for (const HumanDoor& door : doors.doors()) {
      ProcessDoor(door, current_map_name);
    }
  }

  void ProcessDoor(const HumanDoor& h_door,
                   const std::string& current_map_name) {
    if (h_door.type() == DoorType::EVENT) {
      return;
    }

    if (!id_mappings_.maps().contains(current_map_name) ||
        !id_mappings_.maps()
             .at(current_map_name)
             .doors()
             .contains(h_door.name())) {
      auto& maps = *id_mappings_.mutable_maps();
      auto& doors = *maps[current_map_name].mutable_doors();
      doors[h_door.name()] = next_id_++;
    }
  }

  void ProcessRooms(std::filesystem::path path,
                    const std::string& current_map_name) {
    for (auto const& dir_entry : std::filesystem::directory_iterator(path)) {
      auto room = ReadMessageFromFile<HumanRoom>(dir_entry.path().string());
      ProcessRoom(room, current_map_name);
    }
  }

  void ProcessRoom(const HumanRoom& h_room,
                   const std::string& current_map_name) {
    for (const HumanPanel& h_panel : h_room.panels()) {
      if (!id_mappings_.maps().contains(current_map_name) ||
          !id_mappings_.maps()
               .at(current_map_name)
               .rooms()
               .contains(h_room.name()) ||
          !id_mappings_.maps()
               .at(current_map_name)
               .rooms()
               .at(h_room.name())
               .panels()
               .contains(h_panel.name())) {
        auto& maps = *id_mappings_.mutable_maps();
        auto& rooms = *maps[current_map_name].mutable_rooms();
        auto& panels = *rooms[h_room.name()].mutable_panels();
        panels[h_panel.name()] = next_id_++;
      }
    }
  }

 private:
  std::string mapdir_;

  uint64_t next_id_ = 0;

  IdMappings id_mappings_;
};

}  // namespace
}  // namespace com::fourisland::lingo2_archipelago

int main(int argc, char** argv) {
  if (argc != 2) {
    std::cout << "Incorrect argument count." << std::endl;
    std::cout << "Usage: assign_ids [path to map directory]" << std::endl;
    return 1;
  }

  std::string mapdir = argv[1];

  com::fourisland::lingo2_archipelago::AssignIds assign_ids(mapdir);
  assign_ids.Run();

  return 0;
}