#!/usr/bin/env bash

POD_BASE_DIR=${POD_BASE_DIR:-~/Music/}
POD_SUB_DIR=${POD_SUB_DIR:-Podcasts}

POD_EXPORT_BRANCH=${POD_EXPORT_BRANCH:-master}
POD_EXPORT_TARGET=${POD_EXPORT_TARGET:-sansa-cast}

show_usage() {
    echo "$(basename $0) [ list | list-all | play [ FILE ] | pick [-x] | pause | stop | listened | update-feeds | wanted | export [ BRANCH [ TARGET ] ] ]" >&2
}

show_help() {
    show_usage
    cat <<EOF
$(basename $0): Manage podcasts

help                     : show help
list                     : list local podcast episodes
list-all                 : list all podcast episodes
play [ FILE ]            : if FILE, play, picking up from where last paused/stopped
pick  [ -x ]             : pick a podcast to play, if -x, using an X-windows picker
pause                    : pause current episode, saving current location
stop                     : stop current episode, saving current location
listened [ FILE* ]       : mark current episode as listened or if FILES mark them
update-feeds             : update feeds
wanted                   : list wanted episodes
export [ BRNCH ] [ TGT ] : export unlistened podcasts to device
EOF
}

git_annex_wrap() {
    CUR_DIR=$(pwd)
    cd $POD_BASE_DIR
    git annex $@
    RET_VAL=$?
    cd $CUR_DIR
    return $RET_VAL
}

find_unlistened() {
    git_annex_wrap find --metadata "tag=unlistened" --include="${POD_SUB_DIR}/*" $@
}

play_pod() {
    FILE=$1
    PAUSE_LOC=$(git_annex_wrap metadata -g seek_time $FILE)
    if [ "${#PAUSE_LOC}" -lt 1 ] ; then
        mpc add $FILE
        mpc play
    else
        mpc add $FILE
        mpc play
        mpc seek $PAUSE_LOC
    fi
}

get_cur_seek() {
    mpc status | \
        awk 'NR==2 {print $0}' |\
        grep -Eo '([0-9]+:)?[0-9][0-9]:[0-9][0-9]' |\
        head -n 1
}

get_cur_file() {
    mpc status -f '%file%' | head -n 1
}

set_loc() {
    FILE=$1
    SEEK=$2
    if echo $FILE | grep "${POD_SUB_DIR}/" > /dev/null ; then
        git_annex_wrap metadata -s "seek_time=${SEEK}" "${FILE}"
    fi
}

if [ $# -lt 1 ] ; then
    show_usage
    exit 1
fi

CMD=$1
shift

case "$CMD" in
    help)
        show_help
        exit
        ;;
    list)
        if [ $# -lt 1 ] ; then
            find_unlistened --in=here
        else
            find_unlistened --in=here | grep $@
        fi
        exit
        ;;
    list-all)
        if [ $# -lt 1 ] ; then
            find_unlistened
        else
            find_unlistened | grep $@
        fi
        exit
        ;;
    play)
        pod stop
        mpc clear
        if [ $# -lt 1 ] ; then
            for item in $(find_unlistened --in=here) ; do
                mpc add $item
            done
        else
            play_pod $1
        fi
        exit
        ;;
    pick)
        CHOSEN_POD=''
        if [ "$1" == "-x" ] ; then
            CHOSEN_POD=$(find_unlistened --in=here | cut -d'/' -f 2- | rofi -dmenu -p "podcast")
        else
            CHOSEN_POD=$(find_unlistened --in=here | cut -d'/' -f 2- | fzf)
        fi
        if [ "${#CHOSEN_POD}" -gt 0 ] ; then
            play_pod "${POD_SUB_DIR}/${CHOSEN_POD}"
        fi
        exit
        ;;
    pause)
        FILE=$(get_cur_file)
        SEEK=$(get_cur_seek)
        mpc pause
        set_loc $FILE $SEEK
        exit
    ;;
    stop)
        FILE=$(get_cur_file)
        SEEK=$(get_cur_seek)
        mpc stop
        set_loc $FILE $SEEK
        exit
    ;;
    listened)
        if [ $# -lt 1 ] ; then
            FILE=$(get_cur_file)
            git_annex_wrap metadata -s tag=listened "${FILE}"
        else
            if [ $1 = '-' ] ; then
                cat | while read FILE ; do
                    git_annex_wrap metadata -s tag=listened "${FILE}"
                done
            else
                for FILE in $* ; do
                    git_annex_wrap metadata -s tag=listened "${FILE}"
                done
            fi
        fi
        exit
        ;;
    update-feeds)
        CUR_DIR=$(pwd)
        cd $POD_BASE_DIR
        grep -v '^# ' ${POD_SUB_DIR}/podcasts-list.txt |\
            while read -r LINE; do
                URL=${LINE##*	}
                TITLE=${LINE%	*}
                echo "Downloading ${TITLE}..."
                git annex importfeed \
                    --template="${POD_SUB_DIR}/\${feedtitle}/\${itempubdate}-\${itemtitle}\${extension}" \
                    "${URL}"
                echo
            done
        git annex add ${POD_SUB_DIR}
        git commit -m "Caught podcasts"
        git annex find --include="${POD_SUB_DIR}/*" --and --not --metadata tag=listened |\
            xargs git annex metadata --tag unlistened
        mpc update
        cd $CUR_DIR
        exit
        ;;
    wanted)
        find_unlistened --not --in=here
        exit
        ;;
    export)
        BRANCH=${1:-${POD_EXPORT_BRANCH}}
        TARGET=${2:-${POD_EXPORT_TARGET}}
        git_annex_wrap export "${BRANCH}" -t "${TARGET}"
        exit
        ;;
    *)
        show_usage
        echo
        echo "Subcommand $CMD is not valid." >&2
        exit 1
        ;;
esac