#!/bin/bash
#  $HeadURL$ $LastChangedRevision$

#  Modules
. $(miniade) || { echo "${0##*/}: ERROR: miniade failed (hint: run 'miniade' to see error)" >&2; exit 1; }

#  Configurable stuff
TIMEOUT=5

#  Other globals

main()
{
    local MY_ARGS
    local PROGNAME

    #  Defaults for options
    MODE=unset

    #  Process options
    special_opts_handler()
    {
        case $1 in
            --server|--submit|--stop) MODE=${1#--} ;;
            *)      return 1 ;;
        esac
    }
    miniade_process_options --help-handler=usage --special-opts-handler=special_opts_handler MY_ARGS "$@" && set -- "${MY_ARGS[@]}"

    #  Process arguments
    #  (delegated)

    #  Sanity checks and derivations
    [ $MODE != unset ] || usage
    [ "X$LOGNAME" != X ] || miniade_error "LOGNAME: not set"
    miniade_get_progname PROGNAME
    LOCKFILE=/tmp/$PROGNAME-$LOGNAME.lock 
    SOCK=/tmp/$PROGNAME-$LOGNAME.sock

    #  Guts
    ${MODE//-/_} "$@"
}

usage()
{
    local PROGNAME

    miniade_get_progname PROGNAME
    echo "Usage: $PROGNAME [ <standard-options> ] { --server | --submit <url> | --stop }"
    exit 0
}

server()
{
    local PROG BBC_OPTS NEW_BBC_OPTS RADIO_FM_OPTS STANDARD_OPTS

    #  Process arguments
    [ $# = 0 ] || usage

    #  Sanity checks and derivations
    miniade_validate_command mpv socat

    #  Guts
    miniade_debug 10 "server: locking ..."
    if ! miniade_lock $LOCKFILE; then
         miniade_debug 10 "server: server is already running; this is fine"
         return 0
    fi

    miniade_debug 10 "server: launching mpv server ..."
    #
    #  That didn't work but we'll keep the options as they may help with
    #  future problems. 
    #
    #  Other suggestions at the same page were to add reconnect_at_eof,
    #  but I think that should be reconnect_on_eof. Anyway, it didn't
    #  work. Again, we'll keep it.
    STANDARD_OPTS=( 
        --no-terminal 
        --really-quiet 
        --idle 
        --input-ipc-server=$SOCK 
        --audio-device=pulse
        #  '--fs' is so rnd-xmas-film can use the mpv helper
        --fs
    )
    #  https://github.com/mpv-player/mpv/issues/5793#issuecomment-1902197279
    #  suggested the following options to prevent disconnect-without-recovery
    #  issues for Rádio FM. They did not work so we still define them but we
    #  don't use them in the mpv call itself.
    RADIO_FM_OPTS=(
        --stream-lavf-o-append=reconnect_on_http_error=4xx,5xx 
        --stream-lavf-o-append=reconnect_delay_max=30 
        --stream-lavf-o-append=reconnect_streamed=yes 
        --stream-lavf-o-append=reconnect_on_network_error=yes
    )
    #  https://github.com/mpv-player/mpv/issues/13428  suggested the following
    #  options to prevent disconnect-without-recovery issues for BBC Radio 4.
    #  They worked!
    BBC_OPTS=( 
        --loop-playlist=force 
    )
    #  Comments on https://github.com/mpv-player/mpv/issues/13428 suggest this
    #  is enough, and it kept playing for two weeks, before I killed it.
    NEW_BBC_OPTS=(
        --demuxer-lavf-o=max_reload=1000
    )

    #  Note that only NEW_BBC_OPTS is used currently.
    WRA_LAUNCHED_THIS=1 mpv "${STANDARD_OPTS[@]}" "${NEW_BBC_OPTS[@]}" &
        
    #  Since *we* locked above, then *we* can rewrite the lock file :-) But
    #  we need to do it atomically, which means we need to use mv. See
    #  https://unix.stackexchange.com/questions/24395/.
    echo $! > $LOCKFILE.$$
    mv $LOCKFILE.$$ $LOCKFILE
    #  Let it settle.
    sleep 5
}

submit()
{
    local URL

    #  Process arguments
    [ $# = 1 ] || usage
    URL=$1

    #  Sanity checks and derivations
    miniade_lock_is_fresh $LOCKFILE || miniade_error "mpv server seems not to be running"

    #  Guts
    echo "{ \"command\": [ \"loadfile\", \"$URL\", \"replace\" ] }" | socat -u - $SOCK
}

stop()
{
    #  Process arguments
    [ $# = 0 ] || usage

    #  Sanity checks and derivations
    #  No need to send stop if it's not running
    miniade_lock_is_fresh $LOCKFILE || return 0
    
    #  Guts
    echo '{ "command": [ "stop" ] }' | socat -u - $SOCK
}

main "$@"