#!/bin/bash

#################
# Launcher init #
#################

START=$(date +%s.%N)

# ensure_dir_exists calls `mkdir -p` if the given path is not a directory.
# This speeds up execution time by avoiding unnecessary calls to mkdir.
#
# Usage: ensure_dir_exists <path> [<mkdir-options>]...
#
function ensure_dir_exists() {
  [ -d "$1" ] ||  mkdir -p "$@"
}

declare -A PIDS
function async_exec() {
  "$@" &
  PIDS[$!]=$*
}
function wait_for_async_execs() {
  for pid in "${!PIDS[@]}"
  do
    wait "$pid" && continue || echo "ERROR: ${PIDS[$pid]} exited abnormally with status $?"
  done
}

# shellcheck source=/dev/null
source "$SNAP_USER_DATA/.last_revision" 2>/dev/null || true
if [ "$SNAP_DESKTOP_LAST_REVISION" = "$SNAP_REVISION" ]; then
  needs_update=false
else
  needs_update=true
fi

# Set $REALHOME to the users real home directory
REALHOME=$(getent passwd $UID | cut -d ':' -f 6)

# Set config folder to local path
export XDG_CONFIG_HOME="$SNAP_USER_DATA/.config"
ensure_dir_exists "$XDG_CONFIG_HOME"
chmod 700 "$XDG_CONFIG_HOME"

# If the user has modified their user-dirs settings, force an update
if [[ -f "$REALHOME/.config/user-dirs.dirs" ]]; then
  if [[ -f "$XDG_CONFIG_HOME/user-dirs.dirs.md5sum" ]]; then
    if [[ "$(md5sum < "$REALHOME/.config/user-dirs.dirs")" != "$(cat "$XDG_CONFIG_HOME/user-dirs.dirs.md5sum")" ||
          ( -f "$XDG_CONFIG_HOME/user-dirs.locale.md5sum" &&
            "$(md5sum < "$REALHOME/.config/user-dirs.locale")" != "$(cat "$XDG_CONFIG_HOME/user-dirs.locale.md5sum")" ) ]]; then
      needs_update=true
    fi
  else
    # shellcheck disable=SC2034
    needs_update=true
  fi
fi

if [ "$SNAP_ARCH" = "amd64" ]; then
  ARCH="x86_64-linux-gnu"
elif [ "$SNAP_ARCH" = "armhf" ]; then
  ARCH="arm-linux-gnueabihf"
elif [ "$SNAP_ARCH" = "arm64" ]; then
  ARCH="aarch64-linux-gnu"
elif [ "$SNAP_ARCH" = "ppc64el" ]; then
  ARCH="powerpc64le-linux-gnu"
else
  ARCH="$SNAP_ARCH-linux-gnu"
fi

export SNAP_LAUNCHER_ARCH_TRIPLET="$ARCH"

# Don't LD_PRELOAD bindtextdomain for classic snaps
if ! grep -qs "^\s*confinement:\s*classic\s*" "$SNAP/meta/snap.yaml"; then
  if [ -f "$SNAP/gnome-platform/lib/$ARCH/bindtextdomain.so" ]; then
    export LD_PRELOAD="$LD_PRELOAD:$SNAP/gnome-platform/\$LIB/bindtextdomain.so"
  elif [ -f "$SNAP/lib/$ARCH/bindtextdomain.so" ]; then
    export LD_PRELOAD="$LD_PRELOAD:$SNAP/\$LIB/bindtextdomain.so"
  fi
fi


###############################################
# Launcher common exports for any desktop app #
###############################################

# Note: We avoid using `eval` because we don't want to expand variable names
#       in paths. For example: LD_LIBRARY_PATH paths might contain `$LIB`.
function prepend_dir() {
  local -n var="$1"
  local dir="$2"
  # We can't check if the dir exists when the dir contains variables
  if [[ "$dir" == *"\$"*  || -d "$dir" ]]; then
    export "${!var}=${dir}${var:+:$var}"
  fi
}

function append_dir() {
  local -n var="$1"
  local dir="$2"
  # We can't check if the dir exists when the dir contains variables
  if [[ "$dir" == *"\$"*  || -d "$dir" ]]; then
    export "${!var}=${var:+$var:}${dir}"
  fi
}

function can_open_file() {
  [ -f "$1" ] && [ -r "$1" ]
}

function update_xdg_dirs_values() {
  local save_initial_values=false
  local XDG_DIRS="DOCUMENTS DESKTOP DOWNLOAD MUSIC PICTURES VIDEOS PUBLICSHARE TEMPLATES"
  unset XDG_SPECIAL_DIRS_PATHS

  if [ -f "${XDG_CONFIG_HOME:-$HOME/.config}/user-dirs.dirs" ]; then
    # shellcheck source=/dev/null
    source "${XDG_CONFIG_HOME:-$HOME/.config}/user-dirs.dirs"
  fi

  if [ -z ${XDG_SPECIAL_DIRS+x} ]; then
    save_initial_values=true
  fi

  for d in $XDG_DIRS; do
    var="XDG_${d}_DIR"
    value="${!var}"

    if [ "$save_initial_values" = true ]; then
      XDG_SPECIAL_DIRS+=("$var")
      XDG_SPECIAL_DIRS_INITIAL_PATHS+=("$value")
    fi

    XDG_SPECIAL_DIRS_PATHS+=("$value")
  done
}

function is_subpath() {
  dir="$(realpath "$1")"
  parent="$(realpath "$2")"
  [ "${dir##$parent/}" != "$dir" ] && return 0 || return 1
}

append_dir LD_LIBRARY_PATH "$SNAP_DESKTOP_RUNTIME/lib/$ARCH"
append_dir LD_LIBRARY_PATH "$SNAP_DESKTOP_RUNTIME/usr/lib/$ARCH"
append_dir LD_LIBRARY_PATH "$SNAP_DESKTOP_RUNTIME/usr/lib"
append_dir LD_LIBRARY_PATH "$SNAP_DESKTOP_RUNTIME/lib"
prepend_dir PATH "$SNAP_DESKTOP_RUNTIME/usr/bin"

# XDG Config
prepend_dir XDG_CONFIG_DIRS "$SNAP_DESKTOP_RUNTIME/etc/xdg"
prepend_dir XDG_CONFIG_DIRS "$SNAP/etc/xdg"

# Define snaps' own data dir
prepend_dir XDG_DATA_DIRS "$SNAP_DESKTOP_RUNTIME/usr/share"
prepend_dir XDG_DATA_DIRS "$SNAP/usr/share"
prepend_dir XDG_DATA_DIRS "$SNAP/share"
prepend_dir XDG_DATA_DIRS "$SNAP/data-dir"
prepend_dir XDG_DATA_DIRS "$SNAP_USER_DATA"

# Set XDG_DATA_HOME to local path
export XDG_DATA_HOME="$SNAP_USER_DATA/.local/share"
ensure_dir_exists "$XDG_DATA_HOME"

# Workaround for GLib < 2.53.2 not searching for schemas in $XDG_DATA_HOME:
#   https://bugzilla.gnome.org/show_bug.cgi?id=741335
prepend_dir XDG_DATA_DIRS "$XDG_DATA_HOME"

# Set cache folder to local path
export XDG_CACHE_HOME="$SNAP_USER_COMMON/.cache"
if [[ -d "$SNAP_USER_DATA/.cache" && ! -e "$XDG_CACHE_HOME" ]]; then
  # the .cache directory used to be stored under $SNAP_USER_DATA, migrate it
  mv "$SNAP_USER_DATA/.cache" "$SNAP_USER_COMMON/"
fi
ensure_dir_exists "$XDG_CACHE_HOME"

# Create $XDG_RUNTIME_DIR if not exists (to be removed when LP: #1656340 is fixed)
# shellcheck disable=SC2174
ensure_dir_exists "$XDG_RUNTIME_DIR" -m 700

# Ensure the app finds locale definitions (requires locales-all to be installed)
append_dir LOCPATH "$SNAP_DESKTOP_RUNTIME/usr/lib/locale"

# If any, keep track of where XDG dirs were so we can potentially migrate the content later
update_xdg_dirs_values

# Setup user-dirs.* or run xdg-user-dirs-update if needed
needs_xdg_update=false
needs_xdg_reload=false
needs_xdg_links=false

if [ "$HOME" != "$SNAP_USER_DATA" ] && ! is_subpath "$XDG_CONFIG_HOME" "$HOME"; then
  for f in user-dirs.dirs user-dirs.locale; do
    if [ -f "$HOME/.config/$f" ]; then
      mv "$HOME/.config/$f" "$XDG_CONFIG_HOME"
      needs_xdg_reload=true
    fi
  done
fi

if can_open_file "$REALHOME/.config/user-dirs.dirs"; then
  # shellcheck disable=SC2154
  if [ "$needs_update" = true ] || [ "$needs_xdg_reload" = true ]; then
    sed "/^#/!s#\$HOME#${REALHOME}#g" "$REALHOME/.config/user-dirs.dirs" > "$XDG_CONFIG_HOME/user-dirs.dirs"
    md5sum < "$REALHOME/.config/user-dirs.dirs" > "$XDG_CONFIG_HOME/user-dirs.dirs.md5sum"
    # It's possible user-dirs.dirs exists when user-dirs.locale doesn't. This
    # simply means the user opted to never ask to translate their user dirs
    if can_open_file "$REALHOME/.config/user-dirs.locale"; then
      cp -a "$REALHOME/.config/user-dirs.locale" "$XDG_CONFIG_HOME"
      md5sum < "$REALHOME/.config/user-dirs.locale" > "$XDG_CONFIG_HOME/user-dirs.locale.md5sum"
    elif [ -f "$XDG_CONFIG_HOME/user-dirs.locale.md5sum" ]; then
      rm "$XDG_CONFIG_HOME/user-dirs.locale.md5sum"
    fi
    needs_xdg_reload=true
  fi
else
  needs_xdg_update=true
  needs_xdg_links=true
fi

if [ $needs_xdg_reload = true ]; then
  update_xdg_dirs_values
  needs_xdg_reload=false
fi

# Check if we can actually read the contents of each xdg dir
for ((i = 0; i < ${#XDG_SPECIAL_DIRS_PATHS[@]}; i++)); do
  if ! can_open_file "${XDG_SPECIAL_DIRS_PATHS[$i]}"; then
    needs_xdg_update=true
    needs_xdg_links=true
    break
  fi
done

# If needs XDG update and xdg-user-dirs-update exists in $PATH, run it
if [ "$needs_xdg_update" = true ] && command -v xdg-user-dirs-update >/dev/null; then
  xdg-user-dirs-update
  update_xdg_dirs_values
fi

# Create links for user-dirs.dirs
if [ "$needs_xdg_links" = true ]; then
  for ((i = 0; i < ${#XDG_SPECIAL_DIRS_PATHS[@]}; i++)); do
    b="$(realpath "${XDG_SPECIAL_DIRS_PATHS[$i]}" --relative-to="$HOME" 2>/dev/null)"
    if [[ -n "$b" && "$b" != "." && -e "$REALHOME/$b" ]]; then
      [ -d "$HOME/$b" ] && rmdir "$HOME/$b" 2> /dev/null
      [ ! -e "$HOME/$b" ] && ln -s "$REALHOME/$b" "$HOME/$b"
    fi
  done
else
  # If we aren't creating new links, check if we have content saved in old locations and move it
  for ((i = 0; i < ${#XDG_SPECIAL_DIRS[@]}; i++)); do
    old="${XDG_SPECIAL_DIRS_INITIAL_PATHS[$i]}"
    new="${XDG_SPECIAL_DIRS_PATHS[$i]}"
    if [ -L "$old" ] && [ -d "$new" ] && [ "$(readlink "$old" 2>/dev/null)" != "$new" ] &&
         (is_subpath "$old" "$SNAP_USER_DATA" || is_subpath "$old" "$SNAP_USER_COMMON"); then
      mv -vn "$old"/* "$new"/ 2>/dev/null
    elif [ -d "$old" ] && [ -d "$new" ] && [ "$old" != "$new" ] &&
         (is_subpath "$old" "$SNAP_USER_DATA" || is_subpath "$old" "$SNAP_USER_COMMON"); then
      mv -vn "$old"/* "$new"/ 2>/dev/null
    fi
  done
fi

# Keep an array of data dirs, for looping through them
IFS=':' read -r -a data_dirs_array <<< "$XDG_DATA_DIRS"

# Font Config and themes
export FONTCONFIG_PATH="$SNAP_DESKTOP_RUNTIME/etc/fonts"
export FONTCONFIG_FILE="$SNAP_DESKTOP_RUNTIME/etc/fonts/fonts.conf"

function make_user_fontconfig {
  echo "<fontconfig>"
  if [ -d "$REALHOME/.local/share/fonts" ]; then
    echo "  <dir>$REALHOME/.local/share/fonts</dir>"
  fi
  if [ -d "$REALHOME/.fonts" ]; then
    echo "  <dir>$REALHOME/.fonts</dir>"
  fi
  for ((i = 0; i < ${#data_dirs_array[@]}; i++)); do
    if [ -d "${data_dirs_array[$i]}/fonts" ]; then
      echo "  <dir>${data_dirs_array[$i]}/fonts</dir>"
    fi
  done
  # We need to include a user-writable cachedir first to support
  # caching of per-user fonts.
  echo '  <cachedir prefix="xdg">fontconfig</cachedir>'
  echo "  <cachedir>$SNAP_COMMON/fontconfig</cachedir>"
  echo "</fontconfig>"
}

if [ "$needs_update" = true ]; then
  rm -rf "$XDG_DATA_HOME"/{fontconfig,fonts,fonts-*,themes,.themes}

  # This fontconfig fragment is installed in a location that is
  # included by the system fontconfig configuration: namely the
  # etc/fonts/conf.d/50-user.conf file.
  ensure_dir_exists "$XDG_CONFIG_HOME/fontconfig"
  async_exec make_user_fontconfig > "$XDG_CONFIG_HOME/fontconfig/fonts.conf"

  # the themes symlink are needed for GTK 3.18 when the prefix isn't changed
  # GTK 3.20 looks into XDG_DATA_DIRS which has connected themes.
  if [ -d "$SNAP/data-dir/themes" ]; then
    ln -sf "$SNAP/data-dir/themes" "$XDG_DATA_HOME"
    ln -sfn "$SNAP/data-dir/themes" "$SNAP_USER_DATA/.themes"
  elif [ -d "$SNAP_DESKTOP_RUNTIME/usr/share/themes" ]; then
    ln -sf "$SNAP_DESKTOP_RUNTIME/usr/share/themes" "$XDG_DATA_HOME"
    ln -sfn "$SNAP_DESKTOP_RUNTIME/usr/share/themes" "$SNAP_USER_DATA/.themes"
  fi
fi

# Testability support
append_dir LD_LIBRARY_PATH "$SNAP/testability"
append_dir LD_LIBRARY_PATH "$SNAP/testability/$ARCH"
append_dir LD_LIBRARY_PATH "$SNAP/testability/$ARCH/mesa"


[ "$needs_update" = true ] && echo "SNAP_DESKTOP_LAST_REVISION=$SNAP_REVISION" > "$SNAP_USER_DATA/.last_revision"

wait_for_async_execs

if [ -n "$SNAP_DESKTOP_DEBUG" ]; then
  echo "desktop-launch elapsed time: $(date +%s.%N --date="$START seconds ago")"
  echo "Now running: exec $*"
fi

PATH="${SNAP}/usr/sbin:${SNAP}/usr/bin:${SNAP}/sbin:${SNAP}/bin"
PATH="${PATH}:${SNAP_CORE_DIR}/usr/sbin:${SNAP_CORE_DIR}/usr/bin:${SNAP_CORE_DIR}/sbin:${SNAP_CORE_DIR}/bin"

# configure python environment
export PYTHONIOENCODING=utf-8
PYTHONPATH=$SNAP/lib/python3.8/site-packages
PYTHONPATH=$SNAP/usr/lib/python3/site-packages:$PYTHONPATH
PYTHONPATH=$SNAP/usr/lib/python3/dist-packages:$PYTHONPATH
export PYTHONPATH
export PYTHON=$SNAP/usr/bin/python3.8
export SNAP_PYTHON=$PYTHON
# ensure curtin points at PYTHON
export PY3OR2_PYTHON=$PYTHON
# base directory for subiquity to locate resources
export SUBIQUITY_ROOT=$SNAP

BIN="$PYTHON -m system_setup.cmd.server"
args=""
for arg in $@; do
  if [ ${arg} = "--server-only" ]; then
    # Just eat that argument. It's useful for the GUI context only,
    # since here the server only startup option is the default.
    continue
  fi
  if [ ${arg} = "-t" -o ${arg} = "--text" ]; then
    BIN="$PYTHON -m system_setup.cmd.tui"
    continue
  fi
  args="$args $arg"
done

exec $BIN $args