#!/bin/bash

set -e

# Be verbose if $DEBUG=1 is set
if [ ! -z "$DEBUG" ] ; then
  env
  set -x
fi

THIS="$0"
args=("$@") # http://stackoverflow.com/questions/3190818/
NUMBER_OF_ARGS="$#"

# Please do not change $VENDORPREFIX as it will allow for desktop files
# belonging to AppImages to be recognized by future AppImageKit components
# such as desktop integration daemons
VENDORPREFIX=appimagekit

find-up () {
  path="$(dirname "$(readlink -f "${THIS}")")"
  while [[ "$path" != "" && ! -e "$path/$1" ]]; do
    path=${path%/*}
  done
  # echo "$path"
}

if [ -z $APPDIR ] ; then
  # Find the AppDir. It is the directory that contains AppRun.
  # This assumes that this script resides inside the AppDir or a subdirectory.
  # If this script is run inside an AppImage, then the AppImage runtime
  # likely has already set $APPDIR
  APPDIR=$(find-up "AppRun")
fi

export PATH="${APPDIR}/usr/bin:${APPDIR}/usr/sbin:${PATH}"
export XDG_DATA_DIRS="./share/:${XDG_DATA_DIRS}"
export LD_LIBRARY_PATH="${APPDIR}/usr/lib:${LD_LIBRARY_PATH}"
export XDG_DATA_DIRS="${APPDIR}/usr/share:${XDG_DATA_DIRS}"
export GSETTINGS_SCHEMA_DIR="${APPDIR}/usr/share/glib-2.0/schemas:${GSETTINGS_SCHEMA_DIR}"

DESKTOP_FILE=$(find "$APPDIR" -maxdepth 1 -name "*.desktop" | head -n 1)
DESKTOP_FILE_NAME=$(basename "${DESKTOP_FILE}")
APP="${DESKTOP_FILE_NAME%.*}"
BIN="$APPDIR/usr/bin/$APP"

trap atexit EXIT

# Note that the following handles 0, 1 or more arguments (file paths)
# which can include blanks but uses a bashism; can the same be achieved
# in POSIX-shell? (FIXME)
# http://stackoverflow.com/questions/3190818
atexit()
{
if [ $NUMBER_OF_ARGS -eq 0 ] ; then
  exec "${BIN}"
else
  exec "${BIN}" "${args[@]}"
fi
}

error()
{
  if [ -x /usr/bin/zenity ] ; then
    LD_LIBRARY_PATH="" zenity --error --text "${1}" 2>/dev/null
  elif [ -x /usr/bin/kdialog ] ; then
    LD_LIBRARY_PATH="" kdialog --msgbox "${1}" 2>/dev/null
  elif [ -x /usr/bin/Xdialog ] ; then
    LD_LIBRARY_PATH="" Xdialog --msgbox "${1}" 2>/dev/null
  else
    echo "${1}"
  fi
  exit 1
}

yesno()
{
  TITLE=$1
  TEXT=$2
  if [ -x /usr/bin/zenity ] ; then
    LD_LIBRARY_PATH="" zenity --question --title="$TITLE" --text="$TEXT" 2>/dev/null || exit 0
  elif [ -x /usr/bin/kdialog ] ; then
    LD_LIBRARY_PATH="" kdialog --caption "Disk auswerfen?" --title "$TITLE" -yesno "$TEXT" || exit 0
  elif [ -x /usr/bin/Xdialog ] ; then
    LD_LIBRARY_PATH="" Xdialog --title "$TITLE" --clear --yesno "$TEXT" 10 80 || exit 0
  else
    echo "zenity, kdialog, Xdialog missing. Skipping ${THIS}."
    exit 0
  fi
}

check_prevent()
{
  FILE=$1
  if [ -e "$FILE" ] ; then
    exit 0
  fi
}

# Exit immediately of one of these files is present
# (e.g., because the desktop environment wants to handle desktop integration itself)
check_prevent "$HOME/.local/share/$VENDORPREFIX/no_desktopintegration"
check_prevent "/usr/share/$VENDORPREFIX/no_desktopintegration"
check_prevent "/etc/$VENDORPREFIX/no_desktopintegration"

# Exit immediately if appimaged is running
pidof appimaged 2>/dev/null && exit 0

# Exit immediately if $DESKTOPINTEGRATION is not empty
if [ ! -z "$DESKTOPINTEGRATION" ] ; then
  exit 0
fi

check_dep()
{
  DEP=$1
  if [ -z $(which $DEP) ] ; then
    echo "$DEP is missing. Skipping ${THIS}."
    exit 0
  fi
}

# Check whether dependencies are present in base system (we do not bundle these)
# http://cgit.freedesktop.org/xdg/desktop-file-utils/
check_dep desktop-file-validate
check_dep update-desktop-database
check_dep desktop-file-install
check_dep xdg-icon-resource
check_dep xdg-mime
check_dep xdg-desktop-menu

if [ ! -f "$DESKTOP_FILE" ] ; then
  echo "Desktop file is missing. Please run ${THIS} from within an AppImage."
  exit 0
fi

if [ -z "$APPIMAGE" ] ; then
  APPIMAGE="$APPDIR/AppRun"
  # Not running from within an AppImage; hence using the AppRun for Exec=
fi

# Determine where the desktop file should be installed
if [[ $EUID -ne 0 ]]; then
   DESTINATION_DIR_DESKTOP="$HOME/.local/share/applications"
   SYSTEM_WIDE=""
else
   # TODO: Check $XDG_DATA_DIRS
   DESTINATION_DIR_DESKTOP="/usr/local/share/applications"
   SYSTEM_WIDE="--mode system" # for xdg-mime and xdg-icon-resource
fi

# Check if the desktop file is already there
# and if so, whether it points to the same AppImage
if [ -e "$DESTINATION_DIR_DESKTOP/$VENDORPREFIX-$DESKTOP_FILE_NAME" ] ; then
  INSTALLED_APP_VERSION=$(grep "^X-AppImage-BuildId=" "$DESTINATION_DIR_DESKTOP/$VENDORPREFIX-$DESKTOP_FILE_NAME" | head -n 1 | cut -d " " -f 1)
  APP_VERSION=$(grep "^X-AppImage-BuildId=" "$DESKTOP_FILE" | head -n 1 | cut -d " " -f 1)
  echo "installed: $INSTALLED_APP_VERSION image: $APP_VERSION"
  if [ "$INSTALLED_APP_VERSION" == "$APP_VERSION" ] ; then
    exit 0
  fi
fi

# We ask the user only if we have found no reason to skip until here
if [ -z "$SKIP" ] ; then
  yesno "Install" "Would you like to integrate $APPIMAGE with your system?\n\nThis will add it to your applications menu and install icons.\nIf you don't do this you can still launch the application by double-clicking on the AppImage."
fi

# If the user has agreed, rewrite and install the desktop file, and the MIME information
if [ -z "$SKIP" ] ; then
  # desktop-file-install is supposed to install .desktop files to the user's
  # applications directory when run as a non-root user,
  # and to /usr/share/applications if run as root
  # but that does not really work for me...
  desktop-file-install --rebuild-mime-info-cache \
    --vendor=$VENDORPREFIX --set-key=Exec --set-value="\"${APPIMAGE}\" %U" \
    --set-key=X-AppImage-Comment --set-value="Generated by ${THIS}" \
    --set-icon="$VENDORPREFIX-$APP" --set-key=TryExec --set-value=${APPIMAGE// /\\s} "$DESKTOP_FILE" \
    --dir "$DESTINATION_DIR_DESKTOP"
  chmod a+x "$DESTINATION_DIR_DESKTOP/"*
  RESOURCE_NAME=$(echo "$VENDORPREFIX-$DESKTOP_FILE_NAME" | sed -e 's/.desktop//g')

  # uninstall previous icons
  xdg-icon-resource uninstall --noupdate --size 16 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 24 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 32 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 48 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 64 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 72 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 96 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 128 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 256 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 512 "$RESOURCE_NAME"
  xdg-icon-resource uninstall --noupdate --size 1024 "$RESOURCE_NAME"

  # Install the icon files for the application
  ICONS=$(find "${APPDIR}/usr/share/icons/" -wholename "*/apps/${APP}.png" 2>/dev/null || true)
  for ICON in $ICONS ; do
    ICON_SIZE=$(echo "${ICON}" | rev | cut -d "/" -f 3 | rev | cut -d "x" -f 1)
    xdg-icon-resource install --context apps --size ${ICON_SIZE} "${ICON}" "${RESOURCE_NAME}"
  done

  xdg-icon-resource forceupdate

  # Install mime type
  find "${APPDIR}/usr/share/mime/" -type f -name *xml -exec xdg-mime install $SYSTEM_WIDE --novendor {} \; 2>/dev/null || true

  # Install the icon files for the mime type; TODO: scalable
  ICONS=$(find "${APPDIR}/usr/share/icons/" -wholename "*/mimetypes/*.png" 2>/dev/null || true)
  for ICON in $ICONS ; do
    ICON_SIZE=$(echo "${ICON}" | rev | cut -d "/" -f 3 | rev | cut -d "x" -f 1)
    xdg-icon-resource install --context mimetypes --size ${ICON_SIZE} "${ICON}" $(basename $ICON | sed -e 's/.png//g')
  done

  xdg-desktop-menu forceupdate
  # for MIME
  gtk-update-icon-cache
fi