// SPDX-License-Identifier: MIT
#include <FEXCore/fextl/fmt.h>
#include <FEXCore/fextl/string.h>

#include "Common/cpp-optparse/OptionParser.h"
#include "XXFileHash.h"

#include "Common/ArgumentLoader.h"
#include "Common/Config.h"

#include <filesystem>
#include <fstream>
#include <iostream>
#include <unistd.h>
#include <optional>
#include <sstream>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <unistd.h>

#include <tiny-json.h>

namespace ArgOptions {
bool AssumeYes = false;
enum class CompressedImageOption {
  OPTION_ASK,
  OPTION_EXTRACT,
  OPTION_ASIS,
};

CompressedImageOption CompressedUsageOption {CompressedImageOption::OPTION_ASK};

enum class ListQueryOption {
  OPTION_ASK,
  OPTION_FIRST,
};

ListQueryOption DistroListOption {ListQueryOption::OPTION_ASK};

fextl::vector<fextl::string> RemainingArgs;

std::string DistroName {};
std::string DistroVersion {};

void ParseArguments(int argc, char** argv) {
  optparse::OptionParser Parser = optparse::OptionParser().description("Tool for fetching RootFS from FEXServers").add_help_option(true);

  Parser.add_option("-y", "--assume-yes").action("store_true").help("Assume yes to prompts");

  Parser.add_option("-x", "--extract").action("store_true").help("Extract compressed image");

  Parser.add_option("-a", "--as-is").action("store_true").help("Use compressed image as-is");

  Parser.add_option("--distro-name").help("Which distro name to select");

  Parser.add_option("--distro-version").help("Which distro version to select");

  Parser.add_option("--distro-list-first").action("store_true").help("When presented the distro-list option, automatically select the first distro if there isn't an exact match.");

  optparse::Values Options = Parser.parse_args(argc, argv);

  if (Options.is_set_by_user("assume_yes")) {
    AssumeYes = Options.get("assume_yes");
  }

  if (Options.is_set_by_user("extract")) {
    CompressedUsageOption = CompressedImageOption::OPTION_EXTRACT;
  }

  if (Options.is_set_by_user("as_is")) {
    CompressedUsageOption = CompressedImageOption::OPTION_ASIS;
  }

  if (Options.is_set_by_user("distro_list_first")) {
    DistroListOption = ListQueryOption::OPTION_FIRST;
  }

  if (Options.is_set_by_user("distro_name")) {
    DistroName = Options["distro_name"];
  }

  if (Options.is_set_by_user("distro_version")) {
    DistroVersion = Options["distro_version"];
  }

  RemainingArgs = Parser.args();
}
} // namespace ArgOptions

namespace Exec {
int32_t ExecAndWaitForResponse(const char* path, char* const* args) {
  pid_t pid = fork();
  if (pid == 0) {
    execvp(path, args);
    _exit(-1);
  } else {
    int32_t Status {};
    waitpid(pid, &Status, 0);
    if (WIFEXITED(Status)) {
      return (int8_t)WEXITSTATUS(Status);
    }
  }

  return -1;
}

int32_t ExecAndWaitForResponseRedirect(const char* path, char* const* args, int stdoutRedirect = -2, int stderrRedirect = -2) {
  pid_t pid = fork();
  if (pid == 0) {
    if (stdoutRedirect == -1) {
      close(STDOUT_FILENO);
    } else if (stdoutRedirect == -2) {
      // Do nothing
    } else {
      if (stdoutRedirect != STDOUT_FILENO) {
        close(STDOUT_FILENO);
      }
      dup2(stdoutRedirect, STDOUT_FILENO);
    }
    if (stderrRedirect == -1) {
      close(STDERR_FILENO);
    } else if (stderrRedirect == -2) {
      // Do nothing
    } else {
      if (stderrRedirect != STDOUT_FILENO) {
        close(STDERR_FILENO);
      }
      dup2(stderrRedirect, STDERR_FILENO);
    }
    execvp(path, args);
    _exit(-1);
  } else {
    int32_t Status {};
    while (waitpid(pid, &Status, 0) == -1 && errno == EINTR)
      ;
    if (WIFEXITED(Status)) {
      return (int8_t)WEXITSTATUS(Status);
    }
  }

  return -1;
}

std::string ExecAndWaitForResponseText(const char* path, char* const* args) {
  int fd[2];
  pipe(fd);

  pid_t pid = fork();

  if (pid == 0) {
    close(fd[0]); // Close read side

    // Redirect stdout to pipe
    dup2(fd[1], STDOUT_FILENO);

    // Close stderr
    close(STDERR_FILENO);

    // We can now close the pipe since the duplications take care of the rest
    close(fd[1]);

    execvp(path, args);
    _exit(-1);
  } else {
    close(fd[1]); // Close write side

    // Nothing larger than this
    char Buffer[1024] {};
    std::string Output {};

    // Read the pipe until it closes
    while (size_t Size = read(fd[0], Buffer, sizeof(Buffer))) {
      Output += std::string_view(Buffer, Size);
    }

    int32_t Status {};
    while (waitpid(pid, &Status, 0) == -1 && errno == EINTR)
      ;
    if (WIFEXITED(Status)) {
      // Return what we've read
      close(fd[0]);
      return Output;
    }
  }

  return {};
}
} // namespace Exec

namespace WorkingAppsTester {
static bool Has_Curl {false};
static bool Has_Squashfuse {false};
static bool Has_Unsquashfs {false};

// EroFS specific
static bool Has_EroFSFuse {false};
static bool Has_EroFSFsck {false};

void CheckCurl() {
  // Check if curl exists on the host
  std::vector<const char*> ExecveArgs = {
    "curl",
    "-V",
    nullptr,
  };

  int32_t Result = Exec::ExecAndWaitForResponseRedirect(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()), -1, -1);
  Has_Curl = Result != -1;
}

void CheckSquashfuse() {
  std::vector<const char*> ExecveArgs = {
    "squashfuse",
    "--help",
    nullptr,
  };

  int32_t Result = Exec::ExecAndWaitForResponseRedirect(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()), -1, -1);
  Has_Squashfuse = Result != -1;
}

void CheckUnsquashfs() {
  std::vector<const char*> ExecveArgs = {
    "unsquashfs",
    "--help",
    nullptr,
  };

  int fd = ::syscall(SYS_memfd_create, "stdout", 0);
  int32_t Result = Exec::ExecAndWaitForResponseRedirect(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()), fd, fd);
  Has_Unsquashfs = Result != -1;
  if (Has_Unsquashfs) {
    // Seek back to the start
    lseek(fd, 0, SEEK_SET);

    // Unsquashfs needs to support zstd
    // Scan its output to find the zstd compressor
    FILE* fp = fdopen(fd, "r");
    char* Line {nullptr};
    size_t Len;

    bool ReadingDecompressors = false;
    bool SupportsZSTD = false;
    while (getline(&Line, &Len, fp) != -1) {
      if (!ReadingDecompressors) {
        if (strstr(Line, "Decompressors available")) {
          ReadingDecompressors = true;
        }
      } else {
        if (strstr(Line, "zstd")) {
          SupportsZSTD = true;
        }
      }
    }

    free(Line);
    fclose(fp);

    // Disable unsquashfs if it doesn't support ZSTD
    if (!SupportsZSTD) {
      Has_Unsquashfs = false;
    }
  }
  close(fd);
}

// EroFS specific tests
void CheckEroFSFuse() {
  std::vector<const char*> ExecveArgs = {
    "erofsfuse",
    "--help",
    nullptr,
  };

  int32_t Result = Exec::ExecAndWaitForResponseRedirect(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()), -1, -1);
  Has_EroFSFuse = Result != -1;
}

void CheckEroFSFsck() {
  std::vector<const char*> ExecveArgs = {
    "fsck.erofs",
    "-V",
    nullptr,
  };

  int32_t Result = Exec::ExecAndWaitForResponseRedirect(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()), -1, -1);
  Has_EroFSFsck = Result != -1;
}

void Init() {
  CheckCurl();
  CheckSquashfuse();
  CheckUnsquashfs();
  CheckEroFSFuse();
  CheckEroFSFsck();
}
} // namespace WorkingAppsTester

namespace DistroQuery {
struct DistroInfo {
  std::string DistroName;
  std::string DistroVersion;
  bool RollingRelease;
  bool Unknown;
};

DistroInfo GetDistroInfo() {
  // Detect these files in order
  //
  // /etc/lsb-release
  // eg:
  // DISTRIB_ID=Ubuntu
  // DISTRIB_RELEASE=21.10
  // DISTRIB_CODENAME=impish
  // DISTRIB_DESCRIPTION="Ubuntu 21.10"
  //
  // /etc/os-release
  // eg:
  // PRETTY_NAME="Ubuntu 21.10"
  // NAME="Ubuntu"
  // VERSION_ID="21.10"
  // VERSION="21.10 (Impish Indri)"
  // VERSION_CODENAME=impish
  // ID=ubuntu
  // ID_LIKE=debian
  // HOME_URL="https://www.ubuntu.com/"
  // SUPPORT_URL="https://help.ubuntu.com/"
  // BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
  // PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
  // UBUNTU_CODENAME=impish
  //
  // /etc/debian_version
  // eg:
  // 11.0
  //
  // uname -r
  // eg:
  // 5.13.0-22-generic
  DistroInfo Info {};
  uint32_t FoundCount {};

  if (std::filesystem::exists("/etc/lsb-release")) {
    std::fstream File("/etc/lsb-release", std::fstream::in);
    std::string Line;
    while (std::getline(File, Line)) {
      if (File.eof() || FoundCount == 2) {
        break;
      }

      std::stringstream ss(Line);
      std::string Key, Value;
      std::getline(ss, Key, '=');
      std::getline(ss, Value, '=');

      if (Key == "DISTRIB_ID") {
        auto ToLower = [](auto Str) {
          std::transform(Str.begin(), Str.end(), Str.begin(), [](unsigned char c) { return std::tolower(c); });
          return Str;
        };
        Info.DistroName = ToLower(Value);
        ++FoundCount;
      } else if (Key == "DISTRIB_RELEASE") {
        Info.DistroVersion = Value;
        ++FoundCount;
      }
    }
  }

  if (FoundCount == 2) {
    Info.Unknown = false;
    if (Info.DistroName == "arch") {
      Info.RollingRelease = true;
    }
    return Info;
  }
  FoundCount = 0;

  if (std::filesystem::exists("/etc/os-release")) {
    std::fstream File("/etc/os-release", std::fstream::in);
    std::string Line;
    while (std::getline(File, Line)) {
      if (File.eof() || FoundCount == 2) {
        break;
      }

      std::stringstream ss(Line);
      std::string Key, Value;
      std::getline(ss, Key, '=');
      std::getline(ss, Value, '=');

      if (Key == "ID") {
        Info.DistroName = Value;
        ++FoundCount;
      } else if (Key == "VERSION_ID") {
        // Ubuntu provides VERSION_ID
        // Strip the two quotes from the VERSION_ID
        Value = Value.substr(1, Value.size() - 2);
        Info.DistroVersion = Value;
        ++FoundCount;
      } else if (Key == "IMAGE_VERSION") {
        // Arch provides IMAGE_VERSION
        Info.DistroVersion = Value;
        ++FoundCount;
      }
    }
  }

  if (FoundCount == 2) {
    Info.Unknown = false;
    if (Info.DistroName == "arch") {
      Info.RollingRelease = true;
    }
    return Info;
  }
  FoundCount = 0;

  if (std::filesystem::exists("/etc/debian_version")) {
    std::fstream File("/etc/debian_version", std::fstream::in);
    std::string Line;

    Info.DistroName = "debian";
    ++FoundCount;
    while (std::getline(File, Line)) {
      Info.DistroVersion = Line;
      ++FoundCount;
    }
  }

  if (FoundCount == 2) {
    Info.Unknown = false;
    return Info;
  }

  Info.DistroName = "Unknown";
  Info.DistroVersion = {};
  Info.Unknown = true;
  return Info;
}
} // namespace DistroQuery

namespace WebFileFetcher {
struct FileTargets {
  // These two are for matching version checks
  std::string DistroMatch;
  std::string VersionMatch;

  // This is a human readable name
  std::string DistroName;

  // This is the URL
  fextl::string URL;

  // This is the hash of the file
  std::string Hash;

  // FileType
  enum class FileType {
    TYPE_UNKNOWN,
    TYPE_SQUASHFS,
    TYPE_EROFS,
  };
  FileType Type;
};

const static std::string DownloadURL = "https://rootfs.fex-emu.gg/RootFS_links.json";

std::string DownloadToString(const std::string& URL) {
  std::vector<const char*> ExecveArgs = {
    "curl",
    URL.c_str(),
    nullptr,
  };

  return Exec::ExecAndWaitForResponseText(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()));
}

bool DownloadToPath(const fextl::string& URL, const fextl::string& Path) {
  auto filename = URL.substr(URL.find_last_of('/') + 1);
  auto PathName = Path + filename;

  std::vector<const char*> ExecveArgs = {
    "curl", URL.c_str(), "-o", PathName.c_str(), nullptr,
  };

  return Exec::ExecAndWaitForResponse(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data())) == 0;
}

bool DownloadToPathWithZenityProgress(const fextl::string& URL, const fextl::string& Path) {
  auto filename = URL.substr(URL.find_last_of('/') + 1);
  auto PathName = Path + filename;

  // -# for progress bar
  // -o for output file
  // -f for silent fail
  std::string CurlPipe = fmt::format("curl -C - -#f {} -o {} 2>&1", URL, PathName);
  const std::string StdBuf = "stdbuf -oL tr '\\r' '\\n'";
  const std::string SedBuf = "sed -u 's/[^0-9]*\\([0-9]*\\).*/\\1/'";
  // zenity --auto-close can't be used since `curl -C` for whatever reason prints 100% at the start.
  // Making zenity vanish immediately
  const std::string ZenityBuf = "zenity --time-remaining --progress --no-cancel --title 'Downloading'";
  std::string BigArgs = fmt::format("{} | {} | {} | {}", CurlPipe, StdBuf, SedBuf, ZenityBuf);
  std::vector<const char*> ExecveArgs = {
    "/bin/sh",
    "-c",
    BigArgs.c_str(),
    nullptr,
  };

  return Exec::ExecAndWaitForResponse(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data())) == 0;
}

struct JsonAllocator {
  jsonPool_t PoolObject;
  std::unique_ptr<std::list<json_t>> json_objects;
};
static_assert(offsetof(JsonAllocator, PoolObject) == 0, "This needs to be at offset zero");

json_t* PoolInit(jsonPool_t* Pool) {
  JsonAllocator* alloc = reinterpret_cast<JsonAllocator*>(Pool);
  alloc->json_objects = std::make_unique<std::list<json_t>>();
  return &*alloc->json_objects->emplace(alloc->json_objects->end());
}

json_t* PoolAlloc(jsonPool_t* Pool) {
  JsonAllocator* alloc = reinterpret_cast<JsonAllocator*>(Pool);
  return &*alloc->json_objects->emplace(alloc->json_objects->end());
}

std::optional<std::vector<FileTargets>> GetRootFSLinks() {
  // Decode the filetargets
  std::string Data = DownloadToString(DownloadURL);

  if (Data.empty()) {
    return std::nullopt;
  }

  JsonAllocator Pool {
    .PoolObject =
      {
        .init = PoolInit,
        .alloc = PoolAlloc,
      },
  };

  const json_t* json = json_createWithPool(&Data.at(0), &Pool.PoolObject);
  if (!json) {
    fprintf(stderr, "Couldn't create json");
    return {};
  }

  const json_t* RootList = json_getProperty(json, "v1");

  if (!RootList) {
    fprintf(stderr, "Couldn't get root list");
    return {};
  }

  std::vector<FileTargets> Targets;

  for (const json_t* RootItem = json_getChild(RootList); RootItem != nullptr; RootItem = json_getSibling(RootItem)) {

    FileTargets Target;
    Target.DistroName = json_getName(RootItem);

    for (const json_t* DataItem = json_getChild(RootItem); DataItem != nullptr; DataItem = json_getSibling(DataItem)) {
      auto DataName = std::string_view {json_getName(DataItem)};

      if (DataName == "DistroMatch") {
        Target.DistroMatch = json_getValue(DataItem);
      } else if (DataName == "DistroVersion") {
        Target.VersionMatch = json_getValue(DataItem);
      } else if (DataName == "URL") {
        Target.URL = json_getValue(DataItem);
      } else if (DataName == "Hash") {
        Target.Hash = json_getValue(DataItem);
      } else if (DataName == "Type") {
        auto DataValue = std::string_view {json_getValue(DataItem)};
        if (DataValue == "squashfs") {
          Target.Type = FileTargets::FileType::TYPE_SQUASHFS;
        } else if (DataValue == "erofs") {
          Target.Type = FileTargets::FileType::TYPE_EROFS;
        } else {
          Target.Type = FileTargets::FileType::TYPE_UNKNOWN;
        }
      }
    }
    bool SupportsSquashFS = WorkingAppsTester::Has_Squashfuse || WorkingAppsTester::Has_Unsquashfs;
    bool SupportsEroFS = WorkingAppsTester::Has_EroFSFuse;
    if ((Target.Type == FileTargets::FileType::TYPE_SQUASHFS && SupportsSquashFS) ||
        (Target.Type == FileTargets::FileType::TYPE_EROFS && SupportsEroFS)) {
      // If we don't understand the type, then we can't use this.
      // Additionally if the type is erofs but the user doesn't have erofsfuse, then we can't use this
      Targets.emplace_back(Target);
    }
  }

  return Targets;
}
} // namespace WebFileFetcher

namespace Zenity {
bool ExecWithQuestion(const fextl::string& Question) {
  fextl::string TextArg = "--text=" + Question;
  const char* Args[] = {
    "zenity",
    "--question",
    TextArg.c_str(),
    nullptr,
  };

  int32_t Result = Exec::ExecAndWaitForResponse(Args[0], const_cast<char* const*>(Args));
  // 0 on Yes, 1 on No
  return Result == 0;
}

void ExecWithInfo(const fextl::string& Text) {
  fextl::string TextArg = "--text=" + Text;
  const char* Args[] = {
    "zenity",
    "--info",
    TextArg.c_str(),
    nullptr,
  };

  Exec::ExecAndWaitForResponse(Args[0], const_cast<char* const*>(Args));
}

bool AskForConfirmation(const fextl::string& Question) {
  return ArgOptions::AssumeYes || ExecWithQuestion(Question);
}

int32_t AskForConfirmationList(const fextl::string& Text, const std::vector<fextl::string>& Arguments) {
  fextl::string TextArg = "--text=" + Text;

  std::vector<const char*> ExecveArgs = {
    "zenity", "--list", TextArg.c_str(), "--hide-header", "--column=Index", "--column=Text", "--hide-column=1",
  };

  std::vector<fextl::string> NumberArgs;
  for (size_t i = 0; i < Arguments.size(); ++i) {
    NumberArgs.emplace_back(std::to_string(i));
  }

  for (size_t i = 0; i < Arguments.size(); ++i) {
    const auto& Arg = Arguments[i];
    ExecveArgs.emplace_back(NumberArgs[i].c_str());
    ExecveArgs.emplace_back(Arg.c_str());
  }
  ExecveArgs.emplace_back(nullptr);

  auto Result = Exec::ExecAndWaitForResponseText(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()));
  if (Result.empty()) {
    return -1;
  }
  return std::stoi(Result);
}

int32_t AskForComplexConfirmationList(const std::string& Text, const std::vector<std::string>& Arguments) {
  std::string TextArg = "--text=" + Text;

  std::vector<const char*> ExecveArgs = {
    "zenity",
    "--list",
    TextArg.c_str(),
  };

  for (auto& Arg : Arguments) {
    ExecveArgs.emplace_back(Arg.c_str());
  }
  ExecveArgs.emplace_back(nullptr);

  auto Result = Exec::ExecAndWaitForResponseText(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data()));
  if (Result.empty()) {
    return -1;
  }
  return std::stoi(Result);
}

int32_t AskForDistroSelection(DistroQuery::DistroInfo& Info, std::vector<WebFileFetcher::FileTargets>& Targets) {
  // Search for an exact match
  int32_t DistroIndex = -1;
  if (!Info.Unknown) {
    for (size_t i = 0; i < Targets.size(); ++i) {
      const auto& Target = Targets[i];

      bool ExactMatch = Target.DistroMatch == Info.DistroName && (Info.RollingRelease || Target.VersionMatch == Info.DistroVersion);
      if (ExactMatch) {
        fextl::string Question = fextl::fmt::format("Found exact match for distro '{}'. Do you want to select this image?", Target.DistroName);
        if (ExecWithQuestion(Question)) {
          DistroIndex = i;
          break;
        }
      }
    }
  }

  if (DistroIndex != -1) {
    return DistroIndex;
  }

  if (ArgOptions::DistroListOption == ArgOptions::ListQueryOption::OPTION_FIRST) {
    // Return the first option if not an exact match.
    return 0;
  }

  std::vector<std::string> Args;

  Args.emplace_back("--column=Index");
  Args.emplace_back("--column=Distro");
  Args.emplace_back("--hide-column=1");
  for (size_t i = 0; i < Targets.size(); ++i) {
    const auto& Target = Targets[i];
    Args.emplace_back(std::to_string(i));
    Args.emplace_back(Target.DistroName);
  }

  std::string Text = "RootFS list selection";
  return AskForComplexConfirmationList(Text, Args);
}

bool ValidateCheckExists(const WebFileFetcher::FileTargets& Target) {
  fextl::string RootFS = FEXCore::Config::GetDataDirectory() + "RootFS/";
  auto filename = Target.URL.substr(Target.URL.find_last_of('/') + 1);
  auto PathName = RootFS + filename;
  uint64_t ExpectedHash = std::stoul(Target.Hash, nullptr, 16);

  std::error_code ec;
  if (std::filesystem::exists(PathName, ec)) {
    const std::vector<fextl::string> Args {
      "Overwrite",
      "Validate",
    };
    fextl::string Text = filename + " already exists. What do you want to do?";
    int Result = AskForConfirmationList(Text, Args);
    if (Result == -1) {
      return false;
    }

    auto Res = XXFileHash::HashFile(PathName);
    if (Result == 0) {
      if (Res.first == true && Res.second == ExpectedHash) {
        fextl::string Text = fextl::fmt::format("{} matches expected hash. Skipping download", filename);
        ExecWithInfo(Text);
        return false;
      }
    } else if (Result == 1) {
      if (Res.first == false || Res.second != ExpectedHash) {
        return AskForConfirmation("RootFS doesn't match hash!\nDo you want to redownload?");
      } else {
        fextl::string Text = fextl::fmt::format("{} matches expected hash", filename);
        ExecWithInfo(Text);
        return false;
      }
    }
  }

  return true;
}

bool ValidateDownloadSelection(const WebFileFetcher::FileTargets& Target) {
  fextl::string Text = fextl::fmt::format("Selected Rootfs: {}\n", Target.DistroName);
  Text += fmt::format("\tURL: {}\n", Target.URL);
  Text += fmt::format("Are you sure that you want to download this image");

  if (AskForConfirmation(Text)) {
    fextl::string RootFS = FEXCore::Config::GetDataDirectory() + "RootFS/";
    std::error_code ec {};
    if (!std::filesystem::exists(RootFS, ec)) {
      // Doesn't exist, create the the folder as a user convenience
      if (!std::filesystem::create_directories(RootFS, ec)) {
        // Well I guess we failed
        Text = fmt::format("Couldn't create {} path for storing RootFS", RootFS);
        ExecWithInfo(Text);
        return false;
      }
    }

    if (!WebFileFetcher::DownloadToPathWithZenityProgress(Target.URL, RootFS)) {
      return false;
    }

    return true;
  }
  return false;
}
} // namespace Zenity

namespace TTY {
bool AskForConfirmation(const fextl::string& Question) {
  if (ArgOptions::AssumeYes) {
    return true;
  }

  auto ToLowerInPlace = [](auto& Str) {
    std::transform(Str.begin(), Str.end(), Str.begin(), [](unsigned char c) { return std::tolower(c); });
  };

  std::cout << Question << std::endl;
  std::cout << "Response {y,yes,1} or {n,no,0}" << std::endl;
  std::string Response;
  std::cin >> Response;

  ToLowerInPlace(Response);
  if (Response == "y" || Response == "yes" || Response == "1") {
    return true;
  } else if (Response == "n" || Response == "no" || Response == "0") {
    return false;
  } else {
    std::cout << "Unknown response. Assuming no" << std::endl;
    return false;
  }
}

void ExecWithInfo(const fextl::string& Text) {
  std::cout << Text << std::endl;
}

int32_t AskForConfirmationList(const fextl::string& Text, const std::vector<fextl::string>& List) {
  fmt::print("{}\n", Text);
  fmt::print("Options:\n");
  fmt::print("\t0: Cancel\n");

  for (size_t i = 0; i < List.size(); ++i) {
    fmt::print("\t{}: {}\n", i + 1, List[i]);
  }

  fmt::print("\t\nResponse {{1-{}}} or 0 to cancel\n", List.size());
  fextl::string Response;
  std::cin >> Response;

  int32_t ResponseInt = std::stol(Response.data(), nullptr, 0);
  if (ResponseInt == 0) {
    return -1;
  } else if (ResponseInt >= 1 && (ResponseInt - 1) < List.size()) {
    return ResponseInt - 1;
  } else {
    std::cout << "Unknown response. Assuming cancel" << std::endl;
    return -1;
  }
}

int32_t AskForDistroSelection(DistroQuery::DistroInfo& Info, std::vector<WebFileFetcher::FileTargets>& Targets) {
  // Search for an exact match
  int32_t DistroIndex = -1;
  if (!Info.Unknown) {
    for (size_t i = 0; i < Targets.size(); ++i) {
      const auto& Target = Targets[i];

      bool ExactMatch = Target.DistroMatch == Info.DistroName && Target.VersionMatch == Info.DistroVersion;
      if (ExactMatch) {
        fextl::string Question = fextl::fmt::format("Found exact match for distro '{}'. Do you want to select this image?", Target.DistroName);
        if (AskForConfirmation(Question)) {
          DistroIndex = i;
          break;
        }
      }
    }
  }

  if (DistroIndex != -1) {
    return DistroIndex;
  }

  if (ArgOptions::DistroListOption == ArgOptions::ListQueryOption::OPTION_FIRST) {
    // Return the first option if not an exact match.
    return 0;
  }

  std::vector<fextl::string> Args;
  for (size_t i = 0; i < Targets.size(); ++i) {
    const auto& Target = Targets[i];
    Args.emplace_back(Target.DistroName);
  }

  fextl::string Text = "RootFS list selection";
  return AskForConfirmationList(Text, Args);
}

bool ValidateCheckExists(const WebFileFetcher::FileTargets& Target) {
  fextl::string RootFS = FEXCore::Config::GetDataDirectory() + "RootFS/";
  auto filename = Target.URL.substr(Target.URL.find_last_of('/') + 1);
  auto PathName = RootFS + filename;
  uint64_t ExpectedHash = std::stoul(Target.Hash, nullptr, 16);

  std::error_code ec;
  if (std::filesystem::exists(PathName, ec)) {
    const std::vector<fextl::string> Args {
      "Overwrite",
      "Validate",
    };
    fextl::string Text = filename + " already exists. What do you want to do?";
    int Result = AskForConfirmationList(Text, Args);
    if (Result == -1) {
      return false;
    }
    fmt::print("Validating RootFS hash...\n");
    auto Res = XXFileHash::HashFile(PathName);
    if (Result == 0) {
      if (Res.first == true && Res.second == ExpectedHash) {
        fmt::print("{} matches expected hash. Skipping downloading\n", filename);
        return false;
      }
    } else if (Result == 1) {
      if (Res.first == false || Res.second != ExpectedHash) {
        fmt::print("RootFS doesn't match hash!\n");
        return AskForConfirmation("Do you want to redownload?");
      } else {
        fmt::print("{} matches expected hash\n", filename);
        return false;
      }
    }
  }

  return true;
}

bool ValidateDownloadSelection(const WebFileFetcher::FileTargets& Target) {
  fmt::print("Selected Rootfs: {}\n", Target.DistroName);
  fmt::print("\tURL: {}\n", Target.URL);

  if (AskForConfirmation("Are you sure that you want to download this image")) {
    fextl::string RootFS = FEXCore::Config::GetDataDirectory() + "RootFS/";
    std::error_code ec {};
    if (!std::filesystem::exists(RootFS, ec)) {
      // Doesn't exist, create the the folder as a user convenience
      if (!std::filesystem::create_directories(RootFS, ec)) {
        // Well I guess we failed
        fmt::print("Couldn't create {} path for storing RootFS\n", RootFS);
        return false;
      }
    }
    auto DoDownload = [&Target, &RootFS]() -> bool {
      if (!WebFileFetcher::DownloadToPath(Target.URL, RootFS)) {
        fmt::print("Couldn't download RootFS\n");
        return false;
      }

      return true;
    };

    while (DoDownload() == false) {
      if (AskForConfirmation("Curl RootFS download failed. Do you want to retry?")) {
        // Loop to retry
      } else {
        return false;
      }
    }

    // Got here then we passed
    return true;
  }
  return false;
}
} // namespace TTY

namespace {
bool IsTTY {};

std::function<bool(const fextl::string& Question)> _AskForConfirmation;
std::function<void(const fextl::string& Text)> _ExecWithInfo;
std::function<int32_t(const fextl::string& Text, const std::vector<fextl::string>& List)> _AskForConfirmationList;
std::function<int32_t(DistroQuery::DistroInfo& Info, std::vector<WebFileFetcher::FileTargets>& Targets)> _AskForDistroSelection;
std::function<bool(const WebFileFetcher::FileTargets& Target)> _ValidateCheckExists;
std::function<bool(const WebFileFetcher::FileTargets& Target)> _ValidateDownloadSelection;

void CheckTTY() {
  IsTTY = isatty(STDOUT_FILENO);

  if (IsTTY) {
    _AskForConfirmation = TTY::AskForConfirmation;
    _ExecWithInfo = TTY::ExecWithInfo;
    _AskForConfirmationList = TTY::AskForConfirmationList;
    _AskForDistroSelection = TTY::AskForDistroSelection;
    _ValidateCheckExists = TTY::ValidateCheckExists;
    _ValidateDownloadSelection = TTY::ValidateDownloadSelection;
  } else {
    _AskForConfirmation = Zenity::AskForConfirmation;
    _ExecWithInfo = Zenity::ExecWithInfo;
    _AskForConfirmationList = Zenity::AskForConfirmationList;
    _AskForDistroSelection = Zenity::AskForDistroSelection;
    _ValidateCheckExists = Zenity::ValidateCheckExists;
    _ValidateDownloadSelection = Zenity::ValidateDownloadSelection;
  }
}

bool AskForConfirmation(const fextl::string& Question) {
  return _AskForConfirmation(Question);
}

void ExecWithInfo(const fextl::string& Text) {
  _ExecWithInfo(Text);
}

int32_t AskForConfirmationList(const fextl::string& Text, const std::vector<fextl::string>& Arguments) {
  return _AskForConfirmationList(Text, Arguments);
}

int32_t AskForDistroSelection(std::vector<WebFileFetcher::FileTargets>& Targets) {
  auto Info = DistroQuery::GetDistroInfo();

  if (!ArgOptions::DistroName.empty()) {
    Info.DistroName = ArgOptions::DistroName;
  }
  if (!ArgOptions::DistroVersion.empty()) {
    Info.DistroVersion = ArgOptions::DistroVersion;
  }

  return _AskForDistroSelection(Info, Targets);
}

bool ValidateCheckExists(const WebFileFetcher::FileTargets& Target) {
  return _ValidateCheckExists(Target);
}

bool ValidateDownloadSelection(const WebFileFetcher::FileTargets& Target) {
  return _ValidateDownloadSelection(Target);
}
} // namespace

namespace ConfigSetter {
void SetRootFSAsDefault(const fextl::string& RootFS) {
  fextl::string Filename = FEXCore::Config::GetConfigFileLocation();
  auto LoadedConfig = FEX::Config::CreateMainLayer(&Filename);
  LoadedConfig->Load();
  LoadedConfig->EraseSet(FEXCore::Config::ConfigOption::CONFIG_ROOTFS, RootFS);
  FEX::Config::SaveLayerToJSON(Filename, LoadedConfig.get());
}
} // namespace ConfigSetter

namespace UnSquash {
bool UnsquashRootFS(const fextl::string& Path, const fextl::string& RootFS, const fextl::string& FolderName) {
  auto TargetFolder = Path + FolderName;

  bool Extract = true;
  std::error_code ec;
  if (std::filesystem::exists(TargetFolder, ec)) {
    fextl::string Question = "Target folder \"" + FolderName + "\" already exists. Overwrite?";
    if (AskForConfirmation(Question)) {
      if (std::filesystem::remove_all(TargetFolder, ec) != ~0ULL) {
        Extract = true;
      }
    }
  }

  if (Extract) {
    const std::vector<const char*> ExecveArgs = {
      "unsquashfs", "-f", "-d", TargetFolder.c_str(), RootFS.c_str(), nullptr,
    };

    return Exec::ExecAndWaitForResponse(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data())) == 0;
  }

  return false;
}

bool ExtractEroFS(const fextl::string& Path, const fextl::string& RootFS, const fextl::string& FolderName) {
  auto TargetFolder = Path + FolderName;

  bool Extract = true;
  std::error_code ec;
  if (std::filesystem::exists(TargetFolder, ec)) {
    fextl::string Question = "Target folder \"" + FolderName + "\" already exists. Overwrite?";
    if (AskForConfirmation(Question)) {
      if (std::filesystem::remove_all(TargetFolder, ec) != ~0ULL) {
        Extract = true;
      }
      if (ec) {
        ExecWithInfo("Couldn't remove previous directory. Won't extract.");
      }
    }
  }

  if (Extract) {
    ExecWithInfo("Extracting Erofs. This might take a few minutes.");

    const auto ExtractOption = fmt::format("--extract={}", TargetFolder);
    const std::vector<const char*> ExecveArgs = {
      "fsck.erofs",
      ExtractOption.c_str(),
      RootFS.c_str(),
      nullptr,
    };

    return Exec::ExecAndWaitForResponse(ExecveArgs[0], const_cast<char* const*>(ExecveArgs.data())) == 0;
  }

  return false;
}
} // namespace UnSquash

int main(int argc, char** argv, char** const envp) {
  CheckTTY();
  FEX::Config::LoadConfig(true, false, argc, argv, envp, false, {});

  // Reload the meta layer
  FEXCore::Config::ReloadMetaLayer();

  ArgOptions::ParseArguments(argc, argv);

  if (ArgOptions::RemainingArgs.size()) {
    auto Res = XXFileHash::HashFile(ArgOptions::RemainingArgs[0]);
    if (Res.first) {
      fmt::print("{} has hash: {:x}\n", ArgOptions::RemainingArgs[0], Res.second);
    } else {
      fmt::print("Couldn't generate hash for {}\n", ArgOptions::RemainingArgs[0]);
    }
    return 0;
  }

  WorkingAppsTester::Init();
  // Check if curl exists on the host
  if (!WorkingAppsTester::Has_Curl) {
    ExecWithInfo("curl is required to use this tool. Please install curl before using.");
    return -1;
  }
  if (!WorkingAppsTester::Has_Squashfuse && !WorkingAppsTester::Has_Unsquashfs && !WorkingAppsTester::Has_EroFSFuse) {
    // We need at least one tool to mount or extract image files
    ExecWithInfo("squashfuse, unsquashfs, or erofsfuse is required to use this tool. Please install one before using.");
    return -1;
  }

  FEX_CONFIG_OPT(LDPath, ROOTFS);

  std::error_code ec;
  fextl::string Question {};
  if (LDPath().empty() || std::filesystem::exists(LDPath(), ec) == false) {
    Question = "RootFS not found. Do you want to try and download one?";
  } else {
    Question = "RootFS is already in use. Do you want to check the download list?";
  }

  if (AskForConfirmation(Question)) {
    auto TargetReturn = WebFileFetcher::GetRootFSLinks();
    if (!TargetReturn.has_value()) {
      ExecWithInfo("Couldn't download rootfs list from the server. Try again in a minute or report on the fex-emu issue tracker.");
      return -1;
    }

    auto Targets = TargetReturn.value();

    if (Targets.empty()) {
      ExecWithInfo("Couldn't parse rootfs definition URL.");
      return -1;
    }

    int32_t DistroIndex = AskForDistroSelection(Targets);
    if (DistroIndex != -1) {
      const auto& Target = Targets[DistroIndex];
      fextl::string RootFS = FEXCore::Config::GetDataDirectory() + "RootFS/";
      auto filename = Target.URL.substr(Target.URL.find_last_of('/') + 1);
      auto PathName = RootFS + filename;

      if (!ValidateCheckExists(Target)) {
        // Keep going
      } else {
        auto ValidateDownload = [&Target, &PathName]() -> std::pair<int32_t, bool> {
          std::error_code ec;
          if (ValidateDownloadSelection(Target)) {
            uint64_t ExpectedHash = std::stoul(Target.Hash, nullptr, 16);

            if (std::filesystem::exists(PathName, ec)) {
              auto Res = XXFileHash::HashFile(PathName);
              if (Res.first == false || Res.second != ExpectedHash) {
                fextl::string Text = fextl::fmt::format("Couldn't hash the rootfs or hash didn't match\n");
                Text += fmt::format("Hash {:x} != Expected Hash {:x}\n", Res.second, ExpectedHash);
                ExecWithInfo(Text);
                return std::make_pair(-1, true);
              }
            } else {
              ExecWithInfo("Correctly downloaded RootFS but doesn't exist?");
              return std::make_pair(-1, false);
            }
          } else {
            ExecWithInfo("Couldn't download rootfs for some reason.");
            return std::make_pair(-1, false);
          }

          return std::make_pair(0, false);
        };

        std::pair<int32_t, bool> Result {};
        while ((Result = ValidateDownload()).second == true && Result.first == -1) {

          if (AskForConfirmation("Do you want to try downloading the RootFS again?")) {
            // Continue the loop
          } else {
            // Didn't want to retry, just exit now
            return Result.first;
          }
        }

        // Early exit on other errors
        if (Result.first == -1 && Result.second == false) {
          return Result.first;
        }
      }

      struct ExtractStrings {
        const char* ExtractOrAsIs;
        const char* AsIsSinceMounterNonFunctional;
        const char* AsIsSinceExtractorNonFunctional;
        const char* AsIsSinceNothingWorks;
      };

      ArgOptions::CompressedImageOption UseImageAs {ArgOptions::CompressedUsageOption};
      bool HasExtractor {};
      bool HasMounter {};
      std::function<bool(const fextl::string& Path, const fextl::string& RootFS, const fextl::string& FolderName)> ExtractHelper;
      ExtractStrings ExtractingStrings;
      if (Target.Type == WebFileFetcher::FileTargets::FileType::TYPE_SQUASHFS) {
        HasExtractor = WorkingAppsTester::Has_Unsquashfs;
        HasMounter = WorkingAppsTester::Has_Squashfuse;
        ExtractHelper = UnSquash::UnsquashRootFS;
        ExtractingStrings = {
          "Do you wish to extract the squashfs file or use it as-is?",
          "Squashfuse doesn't work. Do you wish to extract the squashfs file?",
          "Unsquashfs doesn't work. Do you want to use the squashfs file as-is?",
          "Unsquashfs and squashfuse isn't working. Leaving rootfs as-is",
        };
      } else if (Target.Type == WebFileFetcher::FileTargets::FileType::TYPE_EROFS) {
        HasExtractor = WorkingAppsTester::Has_EroFSFsck;
        HasMounter = WorkingAppsTester::Has_EroFSFuse;
        ExtractHelper = UnSquash::ExtractEroFS;
        ExtractingStrings = {
          "Do you wish to extract the erofs file or use it as-is?",
          "erofsfuse doesn't work. Do you wish to extract the erofs file?",
          "Extracting erofs doesn't work. Do you want to use the erofs file as-is?",
          "Extracting erofs and erofsfuse isn't working. Leaving rootfs as-is",
        };
      }

      int32_t Result {};
      std::vector<fextl::string> Args = {
        "Extract",
        "As-Is",
      };

      if (UseImageAs == ArgOptions::CompressedImageOption::OPTION_ASK) {
        if (HasExtractor) {
          if (HasMounter) {
            Result = AskForConfirmationList(ExtractingStrings.ExtractOrAsIs, Args);
            if (Result == 0) {
              UseImageAs = ArgOptions::CompressedImageOption::OPTION_EXTRACT;
            } else if (Result == 1) {
              UseImageAs = ArgOptions::CompressedImageOption::OPTION_ASIS;
            }
          } else {
            Args.pop_back();
            Result = AskForConfirmationList(ExtractingStrings.AsIsSinceMounterNonFunctional, Args);
            if (Result == 0) {
              UseImageAs = ArgOptions::CompressedImageOption::OPTION_EXTRACT;
            }
          }
        } else {
          if (HasMounter) {
            Args.erase(Args.begin());
            Result = AskForConfirmationList(ExtractingStrings.AsIsSinceExtractorNonFunctional, Args);
            if (Result == 0) {
              // We removed an argument, Just change "As-Is" from 0 to 1 for later logic to work
              UseImageAs = ArgOptions::CompressedImageOption::OPTION_ASIS;
            }
          } else {
            Args.erase(Args.begin());
            ExecWithInfo(ExtractingStrings.AsIsSinceNothingWorks);
            UseImageAs = ArgOptions::CompressedImageOption::OPTION_ASIS;
          }
        }
      }

      if (UseImageAs == ArgOptions::CompressedImageOption::OPTION_EXTRACT) {
        auto FolderName = filename.substr(0, filename.find_last_of('.'));
        if (ExtractHelper(RootFS, PathName, FolderName)) {
          // Remove the image file suffix since we extracted to that.
          filename = FolderName;
        }
      }

      if (AskForConfirmation("Do you wish to set this RootFS as default?")) {
        ConfigSetter::SetRootFSAsDefault(filename);
        fextl::string Text = fextl::fmt::format("{} set as default RootFS\n", filename);
        ExecWithInfo(Text);
      }
    }
  }

  return 0;
}