#!/usr/bin/env bash
# Installer for the Embarrassed Shina-chan Linux/Proton fix pack.
#
# Modifies only files inside the game folder and the game's Proton prefix; no
# game binaries ship with this repo. Every modified file is backed up
# (*.orig / user.reg.bak-*) so uninstall.sh can revert.
#
# Usage:
#   ./install.sh [/path/to/steamapps/common/Embarrassed Shina-chan~ .../]
# If no path is given it tries common Steam library locations.
set -euo pipefail
HERE="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
APPID=2326780

find_game() {
  local c
  for c in \
    "$HOME/.steam/steam/steamapps/common/Embarrassed Shina-chan~ the Naked Wandering College Girl" \
    "$HOME/.local/share/Steam/steamapps/common/Embarrassed Shina-chan~ the Naked Wandering College Girl"; do
    [ -f "$c/data/kmyCore.dll" ] && { echo "$c"; return 0; }
  done
  # scan libraryfolders.vdf for extra libraries
  local vdf="$HOME/.steam/steam/steamapps/libraryfolders.vdf"
  [ -f "$vdf" ] || vdf="$HOME/.local/share/Steam/steamapps/libraryfolders.vdf"
  if [ -f "$vdf" ]; then
    local lib g
    while IFS= read -r lib; do
      g="$lib/steamapps/common/Embarrassed Shina-chan~ the Naked Wandering College Girl"
      [ -f "$g/data/kmyCore.dll" ] && { echo "$g"; return 0; }
    done < <(grep -oE '"path"[[:space:]]*"[^"]+"' "$vdf" | sed -E 's/.*"([^"]+)"$/\1/')
  fi
  return 1
}

GAME_ROOT="${1:-$(find_game || true)}"
if [ -z "${GAME_ROOT:-}" ] || [ ! -f "$GAME_ROOT/data/kmyCore.dll" ]; then
  echo "!! Could not locate the game. Pass its folder explicitly:"
  echo "   ./install.sh \"/path/to/steamapps/common/Embarrassed Shina-chan~ the Naked Wandering College Girl\""
  exit 1
fi
echo "Game folder: $GAME_ROOT"
echo

# check every required tool up front so the install never stops halfway through.
# all of these are needed for a working game: gcc builds the runtime hook, and
# dotnet builds the IL patcher for the plugin-path fix, without which no asset
# plugins load and the game stays a grey screen.
missing=""
for tool in gcc patch od dd md5sum dotnet; do
  command -v "$tool" >/dev/null 2>&1 || missing="$missing $tool"
done
if [ -n "$missing" ]; then
  echo "!! missing required tools:$missing"
  echo "   gcc            - builds the runtime hook (fix 4)"
  echo "   patch/od/dd/md5sum - apply and verify the byte/shader patches (fixes 1-3)"
  echo "   dotnet         - the .NET SDK, builds the IL patcher for the plugin-path"
  echo "                    fix (fix 2); needs network access once to fetch Mono.Cecil"
  exit 1
fi
command -v python3 >/dev/null 2>&1 || \
  echo "   note: python3 not found, only needed for the optional Wayland fix 5"
# LD_PRELOAD treats colons and spaces as separators, so a repo path containing
# them would silently break the runtime hook
case "$HERE" in
  *' '*|*:*)
    echo "!! this repo's path contains a space or ':', which LD_PRELOAD cannot handle."
    echo "   Move the repo, e.g.:  mv \"$HERE\" ~/shina-linux-patch   and re-run."
    exit 1;;
esac

echo "[1/5] kmyCore disk-FS"
bash "$HERE/patches/01-kmycore-diskfs.sh" "$GAME_ROOT"

echo "[2/5] bakinplayer plugin path"
bash "$HERE/patches/02-pluginpath/apply.sh" "$GAME_ROOT"

echo "[3/5] shader vin_* keep-alive"
SH="$GAME_ROOT/data/lib/sysresource/shader/include/v2_vpcommon.cgh"
SHPATCH="$HERE/patches/03-shader-vin-keepalive.patch"
if grep -q "VIN_KEEPALIVE" "$SH"; then
  echo "== Fix 3: already applied"
else
  # dry-run first; a partially applied patch would leave every shader
  # referencing an undefined VIN_KEEPALIVE
  if ! patch -p1 -d "$GAME_ROOT" -s -f --dry-run < "$SHPATCH" >/dev/null 2>&1; then
    echo "!! Fix 3: shader source does not match this patch (different game build?)."
    echo "!! Not touching it. v2_vpcommon.cgh left unmodified."
    exit 3
  fi
  [ -f "$SH.orig" ] || cp "$SH" "$SH.orig"
  patch -p1 -d "$GAME_ROOT" -s -f < "$SHPATCH"
  echo "== Fix 3: shader patched, backup at v2_vpcommon.cgh.orig"
fi

echo "[4/5] runtime hook (VAO fix + audio-deadlock cap + IBL LUT)"
HOOKDIR="$HERE/patches/04-runtime-hook"
IBL_SRC="$HOOKDIR/ibl_brdf_lut.bmp"
# the game's per-launch shader/texture extraction lives in the Proton prefix:
TMPBASE="$(cd "$GAME_ROOT/../.." && pwd)/compatdata/$APPID/pfx/drive_c/users/steamuser/AppData/Local/Temp/bakin_engine_tmp"
# both paths end up inside C string literals, so refuse characters that break them
for p in "$IBL_SRC" "$TMPBASE"; do
  case "$p" in
    *'"'*|*'\'*) echo "!! cannot embed a path containing \" or \\ into the hook: $p"; exit 1;;
  esac
done
sed_esc() { printf '%s' "$1" | sed 's/[&|]/\\&/g'; }
sed -e "s|@IBL_SRC@|$(sed_esc "$IBL_SRC")|g" -e "s|@TMPBASE@|$(sed_esc "$TMPBASE")|g" \
    "$HOOKDIR/bakin_minimal.c" > "$HOOKDIR/bakin_minimal.installed.c"
gcc -O2 -shared -fPIC -o "$HOOKDIR/bakin_minimal.so" "$HOOKDIR/bakin_minimal.installed.c" -ldl -lpthread
echo "== built $HOOKDIR/bakin_minimal.so"

echo "[5/5] launcher"
HOOK_SO="$HOOKDIR/bakin_minimal.so"
LAUNCHER="$HERE/launcher.installed.sh"
sed "s|@HOOK_SO@|$(sed_esc "$HOOK_SO")|g" "$HERE/launcher.sh" > "$LAUNCHER"
chmod +x "$LAUNCHER"

echo
echo "======================================================================"
echo "Done. Two manual steps remain:"
echo
echo "1) Steam -> Embarrassed Shina-chan -> Properties -> Launch Options:"
echo "     \"$LAUNCHER\" %command%"
echo
echo "2) Wayland desktops only (keyboard focus). Fully close the game, then:"
echo "     bash \"$HERE/patches/05-wayland-keyboard.sh\" \"$GAME_ROOT\""
echo "   (harmless to skip on X11.)"
echo
echo "Then launch from Steam. To revert everything: ./uninstall.sh \"$GAME_ROOT\""
echo "======================================================================"