//
// Created by martin on 26.03.23.
//

#include "SkinnedMeshResource.h"

#include <fstream>

#include "3rdparty/json/json.hpp"

inline void to_json(nlohmann::json& j, const SyncTrack& syncTrack) {
  j["type"] = "SyncTrack";
  j["duration"] = syncTrack.m_duration;
  for (int i = 0; i < syncTrack.m_num_intervals; i++) {
    j["markers"][i] = syncTrack.m_sync_markers[i];
  }
}

inline void from_json(const nlohmann::json& j, SyncTrack& syncTrack) {
  if (!j.contains("type") || j["type"] != "SyncTrack") {
    std::cerr << "Unable to parse SyncTrack: wrong json type!" << std::endl;
    return;
  }

  syncTrack.m_duration = j["duration"];
  syncTrack.m_num_intervals = j["markers"].size();

  if (syncTrack.m_num_intervals > cSyncTrackMaxIntervals) {
    std::cerr << "Invalid number of sync intervals: found " << syncTrack.m_num_intervals << " maximum is " << cSyncTrackMaxIntervals << "." << std::endl;
    syncTrack = SyncTrack();
  }

  for (int i = 0; i < syncTrack.m_num_intervals; i++) {
    syncTrack.m_sync_markers[i] = j["markers"].at(i);
  }
}

inline void to_json(nlohmann::json& j, const SkinnedMeshResource& skinnedMeshResource) {
  j["type"] = "SkinnedMeshResource";
  j["skeleton"]["file"] = skinnedMeshResource.m_skeleton_file;
  for (int i = 0; i < skinnedMeshResource.m_animation_files.size(); i++) {
    j["animations"][i]["file"] = skinnedMeshResource.m_animation_files[i];
    j["animations"][i]["sync_track"] = skinnedMeshResource.m_sync_tracks[i];
  }
}

inline void from_json(const nlohmann::json& j, SkinnedMeshResource& skinnedMeshResource) {
  if (!j.contains("type") || j["type"] != "SkinnedMeshResource") {
    std::cerr << "Unable to parse SkinnedMeshResource: wrong json type!" << std::endl;
    return;
  }

  if (!j.contains("skeleton") || !j["skeleton"].contains("file")) {
    std::cerr << "Unable to parse SkinnedMeshResource: no skeleton file found!" << std::endl;

  }

  skinnedMeshResource.m_skeleton_file = j["skeleton"]["file"];

  if (j.contains("animations")) {
    int num_animations = j["animations"].size();

    for (int i = 0; i < num_animations; i++) {
      if (!j["animations"][i].contains("file") || !j["animations"][i].contains("sync_track")) {
        std::cerr << "Unable to parse SkinnedMeshResource: invalid animation definition" << std::endl;
        return;
      }

      skinnedMeshResource.m_animation_files.push_back(j["animations"][i]["file"]);
      skinnedMeshResource.m_sync_tracks.push_back(j["animations"][i]["sync_track"].get<SyncTrack>());
    }
  }
}

bool SkinnedMeshResource::saveToFile(const char* filename) const {
  nlohmann::json j = *this;

  std::ofstream output_file(filename);
  output_file << j.dump(4, ' ') << std::endl;
  output_file.close();

  return true;
}

bool SkinnedMeshResource::loadFromFile(const char* filename) {
  if (!std::filesystem::exists(filename)) {
    std::cerr << "Error: file " << filename << " does not exist!" << std::endl;
    return false;
  }

  m_resource_file = filename;
  std::ifstream input_file;
  input_file.open(filename);
  std::stringstream buffer;
  buffer << input_file.rdbuf();

  nlohmann::json j = nlohmann::json::parse(buffer.str(), nullptr, false);

  *this = j.get<SkinnedMeshResource>();

  return true;
}

void SkinnedMeshResource::createInstance(SkinnedMesh& skinnedMesh) const {
  skinnedMesh.LoadSkeleton(m_skeleton_file.c_str());
  for (int i = 0; i < m_animation_files.size(); i++) {
    skinnedMesh.LoadAnimation(m_animation_files[i].c_str());
    skinnedMesh.m_animation_sync_track.back() = m_sync_tracks[i];
  }
}