#!/bin/bash
#
# PlexPass Linux Server download tool v2.3
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
# This tool will login to the Plex homepage, locate the PlexPass
# Plex Media Server for Linux and download it.
#
# Either modify this file to add email and password OR create
# a separate .plexupdate file in your home directory with these
# values.
#
# Returns 0 on success
#         1 on error
#         2 if file already downloaded
#         3 if page layout has changed.
#         4 if download fails
#
# All other return values not documented.
#
# Call program with -h for available options
#
# Enjoy!
#
# Version	Description
# ^^^^^^^	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
#  1.0		Initial version, was able to download from plexapp
#  2.0		Initial version supporting plex.tv
#  2.1		Updated to use options and error codes
#  2.2          Layout changed, so code also changed. Added better
#               resiliance to HTML changes and also better error handling
#  2.3          Now reads an optional config file to avoid having to
#               modify this script.
#

#################################################################
# Set these two to what you need, or create a .plexupdate file
# in your home directory with these two (avoids changing this)
#
EMAIL=
PASS=

#################################################################
# Don't change anything below this point
#

# Load settings from config file if it exists
if [ -f ~/.plexupdate ]; then
	source ~/.plexupdate
fi

# Current pages we need
URL_LOGIN=https://plex.tv/users/sign_in
URL_DOWNLOAD=https://plex.tv/downloads?channel=plexpass

# Defaults
RELEASE="64-bit"
KEEP=no
FORCE=no

# Sanity check
if [ "${EMAIL}" == "" -o "${PASS}" == "" ]; then
	echo "Error: No email and/or password provided, please edit me."
	exit 1
fi

# Parse commandline
set -- $(getopt fhko: -- "$@")
while true;
do
	case "$1" in
	(-h) echo -e "Usage: $(basename $0) [-fhko]\n\nf = Force download even if it exists (WILL NOT OVERWRITE)\nh = This help\nk = Reuse last authentication\no = 32-bit version (default 64 bit)\n"; exit 0;;
	(-f) FORCE=yes;;
	(-k) KEEP=yes;;
	(-o) RELEASE="32-bit";;
	(--) ;;
	(-*) echo "Error: unrecognized option $1" 1>&2; exit 1;;
	(*)  break;;
	esac
	shift
done

# Useful functions
rawurlencode() {
	local string="${1}"
	local strlen=${#string}
	local encoded=""

	for (( pos=0 ; pos<strlen ; pos++ )); do
		c=${string:$pos:1}
		case "$c" in
		[-_.~a-zA-Z0-9] ) o="${c}" ;;
		* )               printf -v o '%%%02x' "'$c"
	esac
	encoded+="${o}"
	done
	echo "${encoded}"
}

keypair() {
	local key="$( rawurlencode "$1" )"
	local val="$( rawurlencode "$2" )"

	echo "${key}=${val}"
}

# Fields we need to submit for login to work
#
# Field			Value
# utf8			&#x2713;
# authenticity_token	<Need to be obtained from web page>
# user[login]		$EMAIL
# user[password]	$PASSWORD
# user[remember_me]	0
# commit		Sign in

# If user wants, we skip authentication, but only if previous auth exists
if [ "${KEEP}" != "yes" -o ! -f /tmp/kaka ]; then
	echo -n "Authenticating..."
	# Clean old session
	rm /tmp/kaka 2>/dev/null

	# Get initial seed we need to authenticate
	SEED=$(wget --save-cookies /tmp/kaka --keep-session-cookies ${URL_LOGIN} -O - 2>/dev/null | grep 'name="authenticity_token"' | sed 's/.*value=.\([^"]*\).*/\1/')
	if [ $? -ne 0 -o "${SEED}" == "" ]; then
		echo "Error: Unable to obtain authentication token, page changed?"
		exit 1
	fi

	# Build post data
	echo -ne  >/tmp/postdata  "$(keypair "utf8" "&#x2713;" )"
	echo -ne >>/tmp/postdata "&$(keypair "authenticity_token" "${SEED}" )"
	echo -ne >>/tmp/postdata "&$(keypair "user[login]" "${EMAIL}" )"
	echo -ne >>/tmp/postdata "&$(keypair "user[password]" "${PASS}" )"
	echo -ne >>/tmp/postdata "&$(keypair "user[remember_me]" "0" )"
	echo -ne >>/tmp/postdata "&$(keypair "commit" "Sign in" )"

	# Authenticate
	wget --load-cookies /tmp/kaka --save-cookies /tmp/kaka --keep-session-cookies "${URL_LOGIN}" --post-file=/tmp/postdata -O /dev/null 2>/dev/null
	RET=$?

	# Delete authentication data ... Bad idea to let that stick around
	rm /tmp/postdata

	# Provide some details to the end user
	if [ ${RET} -ne 0 ]; then
		echo "Error: Unable to authenticate"
		exit 1
	fi
	echo "OK"
fi

# Extract the URL for our release
echo -n "Finding download URL for ${RELEASE}..."
DOWNLOAD=$(wget --load-cookies /tmp/kaka --save-cookies /tmp/kaka --keep-session-cookies "${URL_DOWNLOAD}" -O - 2>/dev/null | grep ".deb" | grep "${RELEASE}" | sed "s/.*href=\"\([^\"]*\.deb\)\"[^>]*>${RELEASE}.*/\1/")
echo -e "OK"

if [ "${DOWNLOAD}" == "" ]; then
	echo "Sorry, page layout must have changed, I'm unable to retrieve the URL needed for download"
	exit 3
fi

FILENAME="$(basename 2>/dev/null ${DOWNLOAD})"
if [ $? -ne 0 ]; then
	echo "Failed to parse HTML, download cancelled."
	exit 3
fi

if [ -f "${FILENAME}" -a "${FORCE}" != "yes" ]; then
	echo "File already exists, won't download."
	exit 2
fi

echo -ne "Downloading release \"${FILENAME}\"..."
ERROR=$(wget --load-cookies /tmp/kaka --save-cookies /tmp/kaka --keep-session-cookies "${DOWNLOAD}" 2>&1)
CODE=$?
if [ ${CODE} -ne 0 ]; then
	echo -e "\n  !! Download failed with code ${CODE}, \"${ERROR}\""
	exit ${CODE}
fi
echo "OK"
exit 0