#include "FilesystemMock.h"

#include <cstring>
#include <filesystem>

#include "fsfw/serialize/SerializeIF.h"

ReturnValue_t FilesystemMock::feedFile(const std::string& filename, std::ifstream& file) {
  if (not std::filesystem::exists(filename)) {
    return returnvalue::FAILED;
  }
  size_t fileSize = std::filesystem::file_size(filename);
  FileOpParams params(filename.c_str(), fileSize);
  std::vector<uint8_t> rawData(fileSize);
  file.read(reinterpret_cast<char*>(rawData.data()), static_cast<unsigned int>(rawData.size()));
  createOrAddToFile(filename.data(), 0, rawData.data(), rawData.size());
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::writeToFile(const char* path, size_t offset, const uint8_t* data,
                                          size_t size) {
  createOrAddToFile(path, offset, data, size);
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::readFromFile(const char* path, size_t offset, size_t size,
                                           uint8_t* buffer, size_t& readSize, size_t maxSize) {
  const std::string filename(path);
  const auto iter = fileMap.find(filename);
  if (iter == fileMap.end()) {
    return HasFileSystemIF::FILE_DOES_NOT_EXIST;
  }
  auto& [fileSegQueue, fileRaw] = iter->second;
  size_t readLen = size;
  if (offset + size > fileRaw.size()) {
    if (offset > fileRaw.size()) {
      return returnvalue::OK;
    }
    readLen = fileRaw.size() - offset;
  }
  if (readSize + readLen > maxSize) {
    return SerializeIF::STREAM_TOO_SHORT;
  }
  // std::copy(info.fileRaw.data() + offset, info.fileRaw.data() + offset + readLen, *buffer);
  std::memcpy(buffer, fileRaw.data() + offset, readLen);
  readSize = readLen;
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::createFile(const char* path, const uint8_t* data, size_t size) {
  createOrAddToFile(path, 0, data, size);
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::removeFile(const char* path, FileSystemArgsIF* args) {
  std::string filename(path);
  auto iter = fileMap.find(filename);
  if (iter == fileMap.end()) {
    return HasFileSystemIF::FILE_DOES_NOT_EXIST;
  } else {
    fileMap.erase(iter);
    return returnvalue::OK;
  }
}

ReturnValue_t FilesystemMock::createDirectory(const char* path, bool createParentDirs,
                                              FileSystemArgsIF* args) {
  std::string dirPath = path;
  dirMap[dirPath].createCallCount++;
  dirMap[dirPath].wihParentDir.push(createParentDirs);
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::removeDirectory(const char* path, bool deleteRecurively,
                                              FileSystemArgsIF* args) {
  std::string dirPath = path;
  dirMap[dirPath].delCallCount++;
  dirMap[dirPath].recursiveDeletion.push(deleteRecurively);
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::rename(const char* oldPath, const char* newPath,
                                     FileSystemArgsIF* args) {
  renameQueue.emplace(oldPath, newPath);
  return returnvalue::OK;
}

void FilesystemMock::createOrAddToFile(const char* path, size_t offset, const uint8_t* data,
                                       size_t dataSize) {
  std::string filename(path);
  auto iter = fileMap.find(filename);
  if (iter == fileMap.end()) {
    FileSegmentQueue queue;
    if (dataSize > 0) {
      queue.emplace(filename, offset, data, dataSize);
    }
    FileInfo info;
    info.fileSegQueue = queue;
    if (data != nullptr) {
      info.fileRaw.insert(info.fileRaw.end(), data, data + dataSize);
    }
    fileMap.emplace(filename, info);
  } else {
    FileInfo& info = iter->second;
    info.fileSegQueue.emplace(filename, offset, data, dataSize);
    if (data == nullptr) {
      return;
    }
    // Easiest case: append data to the end
    if (offset == info.fileRaw.size()) {
      info.fileRaw.insert(info.fileRaw.end(), data, data + dataSize);
    } else {
      size_t totalNewLen = offset + dataSize;
      if (totalNewLen > info.fileRaw.size()) {
        info.fileRaw.resize(offset + dataSize);
      }
      std::copy(data, data + dataSize, info.fileRaw.begin() + static_cast<unsigned int>(offset));
    }
  }
}

void FilesystemMock::reset() {
  fileMap.clear();
  dirMap.clear();
  std::queue<RenameInfo> empty;
  std::swap(renameQueue, empty);
}

bool FilesystemMock::fileExists(const char* path, FileSystemArgsIF* args) {
  std::string filename(path);
  auto iter = fileMap.find(filename);
  if (iter == fileMap.end()) {
    return false;
  }
  return true;
}

ReturnValue_t FilesystemMock::truncateFile(const char* path, FileSystemArgsIF* args) {
  truncateCalledOnFile = path;
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::getBaseFilename(const char* path, char* nameBuf, size_t maxLen,
                                              size_t& baseNameLen) {
  return returnvalue::OK;
}

ReturnValue_t FilesystemMock::isDirectory(const char* path, bool& isDirectory) { return false; }

ReturnValue_t FilesystemMock::getFileSize(const char* path, uint64_t& fileSize,
                                          FileSystemArgsIF* args) {
  std::string filename(path);
  auto iter = fileMap.find(filename);
  if (iter != fileMap.end()) {
    fileSize = iter->second.fileRaw.size();
    return true;
  }
  return false;
}