utils/ff-get-flash-video

#!/bin/bash
#
# Try to download a flash movie from current ff window.
#
# Downloads are kept in a cache directory of fixed size, oldest
# files are removed as required. Last download is kept with a
# fixed name such as 'svtplay.flv' or 'youtube.flv'. Older downloads
# are stored with names retrieved from source.
#
# Prerequisites:
#  - One firefox window with a page containing a flash video on
#    current DISPLAY.
#
#  - The CACHE_DIR directory should exist or be possible to create.
#
# Multiple invocations:
#  - A running instance initially blocks other instances from
#    running to not mess with the ff state. Invocations during
#    this time are logged but otherwise silently ignored.
#
#  - Later attempts to start downloading to same location will kill
#    running process and overwrite dl location.
#
#  - Later attempts to start downloading to other locations runs in
#    parallel.
#
# Dependencies:
#    xdotool, xsel, get_flash_videos, zenity, xorg-x11-utils
#
# Bugs:
#    Fragile, does not use stable API:s, just happens to  work
#    occasionally.

readonly FF_WINDOW_NAME='Mozilla Firefox'
readonly DEFAULTS_FILE='/etc/sysconfig/ff-get-flash-video'
readonly DEFAULT_CACHE_SIZE=5


function get_cachedir()
{
    local xdg_setup_dirs="${XDG_CONFIG_HOME:-$HOME/.config}/user-dirs.dirs"
    test -r "$xdg_setup_dirs" && source "$xdg_setup_dirs"
    dir=${XDG_DOWNLOAD_DIR:-$HOME}/flash
    test -d $dir || mkdir $dir || echo "Cannot create $dir" >&2
    echo $dir
}


[ -r $DEFAULTS_FILE ] && source $DEFAULTS_FILE
CACHE_DIR=${CACHE_DIR:-$( get_cachedir )}
CACHE_SIZE=${CACHE_SIZE:-$DEFAULT_CACHE_SIZE}


function usage()
{
    cat <<EOF

Find out what flash video Firefox is running and download it.

Usage: $(basename $0) [options]

Options
  -d <dir>   Download directory, defaults to $CACHE_DIR.
  -s <size>  Cache size i.e., number of downloaded files kept.
             Defaults to $CACHE_SIZE.

Assumes a single firefox window opened with a flash movie running.
EOF
}


function get_options()
{
    while getopts 'd:s:h' opt; do
	case $opt in
	    s) CACHE_SIZE=$OPTARG;;
	    d) CACHE_DIR=$OPTARG;;
	    h) usage; exit 0;;
	    *) usage; exit 1;;
	esac
    done

    LOGFILE="$CACHE_DIR/flash-download.trace"
    LOCK_FILE="$CACHE_DIR/.lock"
    readonly CACHE_SIZE CACHE_DIR LOGFILE LOCK_FILE
}


function error_msg()   { zenity --error --timeout=4 --text="$1"; }

function warning_msg() { zenity --warning --timeout=4 --text="$1"; }

function info_msg()    { zenity --info --timeout=4 --text="$1"; }


function get_size()
# Return size of single file argument on stdout, no file returns "0".
{
    if [ -f $1 ]; then
        ls -l $1 | awk '{print $5}'
    else
        echo "0"
    fi
}


function get_ff_window()
# Return current ff window id, bailing out on missing or multiple
# ff window(s).
{
    local win

    win=$( xdotool search --name "$FF_WINDOW_NAME" ) || win=""
    if [ -z "$win" ]; then
        error_msg "No Firefox window!"
        exit 1
    fi
    if [ "$win" != "${win%% *}" ]; then
       error_msg "Two (or more) Firefox windows"
       exit 1
    fi
    echo $win
}


function get_ff_window_width_height()
# Echo shell line like 'width=xxx height=yyy' for window argument.
{
    local win=$1
    xwininfo -id "$win" |
            awk '/Width:/  { w = $2 }
                 /Height:/ { h = $2 }
                 END       { printf "width=%s height=%s\n", w, h }'
}


function get_fullscreen()
# Echo 'yes' or 'no' reflecting whether ff is running in fullscreen.
{
    local win=$1
    local width height
    eval $( get_ff_window_width_height $win )
    local window_dim="${width}x${height}"

    screen_dim=$( xdpyinfo | awk ' /dimensions:/ { print $2}')

    if [ "$window_dim" = "$screen_dim" ]; then
        echo "yes"
    else
        echo "no"
    fi
}


function get_ff_url()
# Select and copy url from ff (current window) to X clipboard.
{
    fullscreen=$1
    if [[ $fullscreen == *n* ]]; then
        xdotool key alt+d ctrl+c
    else
        xdotool key F11 alt+d ctrl+c F11
    fi
}


function get_ff_location()
# Get location from current ff window
# Arg: ff window id.
{
    local win="$1"
    local fullscreen="$2"

    local width height
    eval $( get_ff_window_width_height $win )

    local X Y SCREEN WINDOW
    eval $(xdotool getmouselocation --shell)
    echo "No-url" | xsel -ib

    xdotool windowactivate "$win"

    # Try to click outside video widget, it doesn't pass alt-d,ctrl-c.
    # alt+d, ctrl+c = "select location bar", "copy" keyboard shortcuts.
    xdotool mousemove --sync $(( $width/2 )) $(( $height - 1 ))
    get_ff_url $fullscreen

    for delay in 0.1 0.2 0.3 0.5 0.8; do
        sleep $delay
        url=$( xsel -ob )
        [[ "$url" != *No-url* ]] && break
        get_ff_url $fullscreen
    done

    if [[ "$url" == *No-url* ]]; then
        error_msg "Can\'t copy url from firefox (!)"
        exit 2
    fi

    xdotool mousemove $X $Y
    echo $url
}


function rotate_cache()
# Ensure there are at most CACHE_SIZE - 1 downloads in cache,
# remove old log files. Rename newest file to it's "native"
# name as hinted by flash-download.
{
    (
        cd $CACHE_DIR
        [ -f ".rename-head" ] && \
            eval "$( cat .rename-head)" && rm ".rename-head"
        rm $( ls -t --hide '*.log' | awk "NR > $((CACHE_SIZE - 1))" ) \
              &>/dev/null || :
        rm $( find . -mtime +1  -name '*.log' ) &>/dev/null || :
    )
}


function check_running_process()
# Exit if there is a running process messing w ff, else accquire lock.
{
    if [ -f $LOCK_FILE ]; then
       local pid=$( cat $LOCK_FILE )
       if [ "$( ps --pid "$pid" -o uid --no-headers )" = '' ]; then
           logger "$0: Removing stale lock file, pid: $pid"
           echo "Removing stale lock file" >&2
           rm -f $LOCK_FILE
       fi
    fi
    local tmp_pid=$( mktemp )
    echo $$ > $tmp_pid
    mv --no-clobber $tmp_pid $LOCK_FILE
    local lock_pid=$(cat $LOCK_FILE)
    rm -f "$tmp_pid"
    if [ "$lock_pid" != "$$" ]; then
        logger "$0: Another instance is messing with FF, exiting"
        exit 3
    fi
}


function get_dl_path
{
    local location=$1
    local key value
    get_flash_videos --info $location | while read key value; do
	[ "$key" = 'Filename:' ] && echo "$value"
    done
}


function setup_nickname()
{
    local location=$1

    local dl_path=$( get_dl_path $location )
    if [ "$dl_path" = "" ] ; then
        error_msg "Can't download from Firefox"
        exit 1
    fi
    local nickname=${location%.*}
    nickname=${nickname#*://}
    nickname=${nickname#www.}.flv
    echo "mv '$nickname' '$dl_path'" > "$CACHE_DIR/.rename-head"
    echo $nickname
}


get_options $@

exec 1>$LOGFILE 2>&1
set -x

check_running_process

wid=$( get_ff_window )
fullscreen=$( get_fullscreen $wid )
location=$( get_ff_location $wid $fullscreen ) || exit 1
nickname=$( setup_nickname $location ) || exit 2

dl_file="$CACHE_DIR/$nickname"
logfile=${dl_file/.flv/.log}
rotate_cache

pkill -f "get_flash_videos.*$dl_file" && sleep 1
get_flash_videos -q -f $dl_file $location  &>$logfile &
dl_pid=$!
rm -f $LOCK_FILE

info_msg "Download started" &

sleep 1; size_1=$( get_size $dl_file)
sleep 10; size_2=$( get_size $dl_file)

if (( "$size_1" == "$size_2" || "$size_2" == '0' ));  then
    msg="Warning: Download seem to have stalled, $size_2 bytes downloaded"
    warning_msg "$msg" &
fi

if wait $dl_pid; then
    info_msg "Download complete"
else
    result=$?
    test $result -gt 127 && echo "Interrupted!" >> $logfile
    echo "Result: $result"  >> $logfile
fi

exit  0