{ lib
, runCommand
, writeShellScriptBin
, makeDesktopItem
, wineWow64Packages
, dxvk
, symlinkJoin
,
}:

let
  wine = wineWow64Packages.stableFull;

  setupVersion = "nsis-launchpad-v2";
  installDirWin = "C:\\Games\\EverQuestLegends";
  installDirUnix = "drive_c/Games/EverQuestLegends";

  setupDxvk = writeShellScriptBin "eqlegends-setup-dxvk" ''
    set -euo pipefail

    mkdir -p "$WINEPREFIX/drive_c/windows/system32" "$WINEPREFIX/drive_c/windows/syswow64"
    cp -Lf ${dxvk.bin}/x64/d3d8.dll ${dxvk.bin}/x64/d3d9.dll ${dxvk.bin}/x64/d3d10core.dll ${dxvk.bin}/x64/d3d11.dll ${dxvk.bin}/x64/dxgi.dll "$WINEPREFIX/drive_c/windows/system32/"
    cp -Lf ${dxvk.bin}/x32/d3d8.dll ${dxvk.bin}/x32/d3d9.dll ${dxvk.bin}/x32/d3d10core.dll ${dxvk.bin}/x32/d3d11.dll ${dxvk.bin}/x32/dxgi.dll "$WINEPREFIX/drive_c/windows/syswow64/"

    wine reg add "HKCU\\Software\\Wine\\DllOverrides" /v d3d8 /t REG_SZ /d native /f
    wine reg add "HKCU\\Software\\Wine\\DllOverrides" /v d3d9 /t REG_SZ /d native /f
    wine reg add "HKCU\\Software\\Wine\\DllOverrides" /v d3d10core /t REG_SZ /d native /f
    wine reg add "HKCU\\Software\\Wine\\DllOverrides" /v d3d11 /t REG_SZ /d native /f
    wine reg add "HKCU\\Software\\Wine\\DllOverrides" /v dxgi /t REG_SZ /d native /f
  '';

  launcher = writeShellScriptBin "eqlegends" ''
    set -euo pipefail

    export WINEARCH=win64
    export WINEDEBUG="''${EQL_WINEDEBUG:--all}"
    export PATH="${wine}/bin:$PATH"

    data_home="''${XDG_DATA_HOME:-$HOME/.local/share}"
    export WINEPREFIX="''${EQL_WINEPREFIX:-$data_home/eqlegends/wine}"
    version_file="$WINEPREFIX/.eqlegends-nix-version"
    launcher_path_file="$WINEPREFIX/.eqlegends-launcher-path"
    dxvk_marker="$WINEPREFIX/.eqlegends-dxvk-enabled"
    launcher_exe="$WINEPREFIX/${installDirUnix}/LaunchPad.exe"

    if [ -f "$launcher_path_file" ]; then
      launcher_exe="$(cat "$launcher_path_file")"
    fi

    find_installer() {
      if [ -n "''${EQL_INSTALLER:-}" ]; then
        printf '%s\n' "$EQL_INSTALLER"
        return
      fi

      if [ -f "$PWD/EQLegends_setup.exe" ]; then
        printf '%s\n' "$PWD/EQLegends_setup.exe"
        return
      fi

      printf '%s\n' ""
    }

    if [ "''${EQL_RESET_PREFIX:-0}" = "1" ]; then
      echo "eqlegends: removing $WINEPREFIX"
      rm -rf "$WINEPREFIX"
    fi

    if [ ! -f "$launcher_exe" ] || [ ! -f "$version_file" ] || [ "$(cat "$version_file" 2>/dev/null || true)" != "${setupVersion}" ]; then
      installer="$(find_installer)"
      if [ -z "$installer" ] || [ ! -f "$installer" ]; then
        cat >&2 <<'EOF'
eqlegends: missing EQLegends_setup.exe

Run from the repository directory containing EQLegends_setup.exe, or set:

  EQL_INSTALLER=/path/to/EQLegends_setup.exe nix run .#eqlegends
EOF
        exit 1
      fi

      echo "eqlegends: creating Wine prefix at $WINEPREFIX"
      rm -rf "$WINEPREFIX"
      mkdir -p "$WINEPREFIX"

      wineboot -u
      wineserver -w

      echo "eqlegends: installing EverQuest Legends LaunchPad with NSIS silent mode..."
      wine "$installer" /S "/D=${installDirWin}"
      # The NSIS installer starts LaunchPad after extraction even in silent mode.
      # Stop that first instance so setup can finish and the wrapper can launch
      # the recorded executable itself.
      wineserver -k || true

      if [ ! -f "$launcher_exe" ]; then
        found_launcher="$(find "$WINEPREFIX/drive_c" -type f -iname LaunchPad.exe | head -n 1 || true)"
        if [ -n "$found_launcher" ]; then
          launcher_exe="$found_launcher"
        fi
      fi

      if [ ! -f "$launcher_exe" ]; then
        echo "eqlegends: LaunchPad.exe was not found after install." >&2
        echo "eqlegends: inspect $WINEPREFIX/drive_c to see where the installer wrote files." >&2
        exit 1
      fi

      printf '%s\n' "$launcher_exe" > "$launcher_path_file"
      echo "${setupVersion}" > "$version_file"
      echo "eqlegends: setup complete."
    fi

    if [ "''${EQL_DXVK:-0}" = "1" ] && [ ! -f "$dxvk_marker" ]; then
      echo "eqlegends: installing DXVK into prefix..."
      ${setupDxvk}/bin/eqlegends-setup-dxvk
      wineserver -w
      touch "$dxvk_marker"
    fi

    if [ "''${EQL_DXVK:-0}" != "1" ] && [ -f "$dxvk_marker" ]; then
      echo "eqlegends: DXVK was previously installed in this prefix." >&2
      echo "eqlegends: run with EQL_DXVK=1 or reset with EQL_RESET_PREFIX=1 to return to WineD3D." >&2
    fi

    cd "$(dirname "$launcher_exe")"
    exec wine "$launcher_exe" "$@"
  '';

  reset = writeShellScriptBin "eqlegends-reset-prefix" ''
    set -euo pipefail

    data_home="''${XDG_DATA_HOME:-$HOME/.local/share}"
    prefix="''${EQL_WINEPREFIX:-$data_home/eqlegends/wine}"
    echo "eqlegends: removing $prefix"
    rm -rf "$prefix"
  '';

  desktopItem = makeDesktopItem {
    name = "eqlegends";
    desktopName = "EverQuest Legends";
    comment = "EverQuest Legends LaunchPad (Wine)";
    exec = "eqlegends";
    categories = [ "Game" ];
  };

  desktopFiles = runCommand "eqlegends-desktop" { } ''
    mkdir -p $out/share/applications
    ln -s ${desktopItem}/share/applications/eqlegends.desktop $out/share/applications/
  '';

in
symlinkJoin {
  name = "eqlegends-launchpad";
  paths = [
    launcher
    reset
    desktopFiles
  ];

  meta = {
    description = "EverQuest Legends LaunchPad wrapper for Wine on NixOS";
    homepage = "https://www.everquest.com/";
    license = lib.licenses.unfree;
    platforms = lib.platforms.linux;
    mainProgram = "eqlegends";
  };
}