di-descript.sh

#!/usr/bin/env zsh -f
# Purpose:	Download and install (and possibly update) the latest version of Descript
#
# From:		Timothy J. Luoma
# Mail:		luomat at gmail dot com
# Date:		2020-05-30
# Verified:	2025-02-18

NAME="$0:t:r"

[[ -e "$HOME/.path" ]] && source "$HOME/.path"

[[ -e "$HOME/.config/di/defaults.sh" ]] && source "$HOME/.config/di/defaults.sh"

INSTALL_TO="${INSTALL_DIR_ALTERNATE-/Applications}/Descript.app"

# https://www.descript.com/download

URL=$(curl --silent --head --location 'https://web.descript.com/download?v2=true&platform=mac' \
	  | awk -F' |\r' '/^location:/{print $2}')

	# NOTE: This version can be behind the actual version of the actual app
	#		so this script will not be reliable for *updating* the app in a
	#		timely fashion. It will work fine for a new install, however.
LATEST_VERSION=$(echo "$URL:t:r" | sed 's#Descript\%20Installer\%20v##g')

FILENAME="${DOWNLOAD_DIR_ALTERNATE-$HOME/Downloads}/${${INSTALL_TO:t:r}// /}-${${LATEST_VERSION}// /}.zip"

if [[ -e "$INSTALL_TO" ]]
then

	INSTALLED_VERSION=$(defaults read "${INSTALL_TO}/Contents/Info" CFBundleShortVersionString)

	autoload is-at-least

	is-at-least "$LATEST_VERSION" "$INSTALLED_VERSION"

	VERSION_COMPARE="$?"

	if [ "$VERSION_COMPARE" = "0" ]
	then
		echo "$NAME: Up-To-Date ($INSTALLED_VERSION)"
		exit 0
	fi

	echo "$NAME: Outdated: $INSTALLED_VERSION vs $LATEST_VERSION"

	FIRST_INSTALL='no'

	if [[ ! -w "$INSTALL_TO" ]]
	then
		echo "$NAME: '$INSTALL_TO' exists, but you do not have 'write' access to it, therefore you cannot update it." >>/dev/stderr

		exit 2
	fi

else

	FIRST_INSTALL='yes'
fi

echo "$NAME: Downloading '$URL' to '$FILENAME':"

curl --continue-at - --fail --location --output "$FILENAME" "$URL"

EXIT="$?"

	## exit 22 means 'the file was already fully downloaded'
[ "$EXIT" != "0" -a "$EXIT" != "22" ] && echo "$NAME: Download of $URL failed (EXIT = $EXIT)" && exit 0

[[ ! -e "$FILENAME" ]] && echo "$NAME: $FILENAME does not exist." && exit 0

[[ ! -s "$FILENAME" ]] && echo "$NAME: $FILENAME is zero bytes." && rm -f "$FILENAME" && exit 0

egrep -q '^Local sha256:$' "$FILENAME:r.txt" 2>/dev/null

EXIT="$?"

if [ "$EXIT" = "1" -o ! -e "$FILENAME:r.txt" ]
then
	(cd "$FILENAME:h" ; \
	echo "\n\nLocal sha256:" ; \
	shasum -a 256 "$FILENAME:t" \
	)  >>| "$FILENAME:r.txt"
fi

TEMPDIR=$(mktemp -d "${TMPDIR-/tmp/}${NAME-$0:r}-XXXXXXXX")

	## make sure that the .zip is valid before we proceed
(command unzip -l "$FILENAME" 2>&1 )>/dev/null

EXIT="$?"

if [ "$EXIT" = "0" ]
then
	echo "$NAME: '$FILENAME' is a valid zip file."

else
	echo "$NAME: '$FILENAME' is an invalid zip file (\$EXIT = $EXIT)"

	mv -fv "$FILENAME" "$TEMPDIR/"

	mv -fv "$FILENAME:r".* "$TEMPDIR/"

	exit 0

fi

	## unzip to a temporary directory
UNZIP_TO=$(mktemp -d "${TEMPDIR}/${NAME}-XXXXXXXX")

echo "$NAME: Unzipping '$FILENAME' to '$UNZIP_TO':"

ditto -xk --noqtn "$FILENAME" "$UNZIP_TO"

EXIT="$?"

if [[ "$EXIT" == "0" ]]
then
	echo "$NAME: Unzip successful"
else
		# failed
	echo "$NAME failed (ditto -xkv '$FILENAME' '$UNZIP_TO')"

	exit 1
fi

	# Open the installer that we just unzipped
INSTALLER_APP=$(find "$UNZIP_TO" -iname 'Descript Installer*' -maxdepth 2 -print)

	# The installer will download and install the app automatically once opened
open -a "${INSTALLER_APP}"

exit 0
#EOF