[BK-2020-03.git] / user / bkmpv2

#!/usr/bin/env bash
# Desc: Wrapper for mpv that accepts directory or file paths via posargs or stdin lines
# Usage: bkmpv2 [DIR]
# Version: 0.1.0
# Depends: GNU Parallel, GNU Bash v5.1.16, mpv v0.34.1, bc v1.07.1
# Ref/Attrib: [1] Tange, Ole. GNU Parallel with Bash Array. 2019-03-24. https://unix.stackexchange.com/a/508365/411854
# Example: find $HOME/Music -type d | bkmpv2
# Example: bkmpv2 $HOME/Music/
# Example: find $HOME -type f -name "*.mp3" | bkmpv2
# Note: Does not follow symlinks

# Find settings
firegex=".+\(aac\|aif\|aiff\|flac\|m4a\|mp3\|mp4\|ogg\|opus\|wav\)$"; # update according to `find . -type f | grep -Eo "\.([[:alnum:]])+$" | sort -u`
fsize="10k"; # default: minimum "10k"
fdepth_posarg="10"; # find depth for positional arguments
fdepth_stdin="1";  # find depth for stdin
fc_falloff="1000"; # characteristic file count falloff in the output
fc_redbase="10"; # logarithm base to reduce output file count

export firegex fsize ; # export for parallel

#===Declare local functions===
yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
must() { "$@" || die "cannot $*"; } # runs args as command, reports args if command fails
checkapp() {
    # Desc: If arg is a command, save result in assoc array 'appRollCall'
    # Usage: checkapp arg1 arg2 arg3 ...
    # Version: 0.1.1
    # Input: global assoc. array 'appRollCall'
    # Output: adds/updates key(value) to global assoc array 'appRollCall'
    # Depends: bash 5.0.3
    local returnState

    #===Process Args===
    for arg in "$@"; do
        if command -v "$arg" 1>/dev/null 2>&1; then # Check if arg is a valid command
            appRollCall[$arg]="true";
            if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
        else
            appRollCall[$arg]="false"; returnState="false";
        fi;
    done;

    #===Determine function return code===
    if [ "$returnState" = "true" ]; then
        return 0;
    else
        return 1;
    fi;
} # Check that app exists
checkfile() {
    # Desc: If arg is a file path, save result in assoc array 'fileRollCall'
    # Usage: checkfile arg1 arg2 arg3 ...
    # Version: 0.1.1
    # Input: global assoc. array 'fileRollCall'
    # Output: adds/updates key(value) to global assoc array 'fileRollCall';
    # Output: returns 0 if app found, 1 otherwise
    # Depends: bash 5.0.3
    local returnState

    #===Process Args===
    for arg in "$@"; do
        if [ -f "$arg" ]; then
            fileRollCall["$arg"]="true";
            if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
        else
            fileRollCall["$arg"]="false"; returnState="false";
        fi;
    done;

    #===Determine function return code===
    if [ "$returnState" = "true" ]; then
        return 0;
    else
        return 1;
    fi;
} # Check that file exists
checkdir() {
    # Desc: If arg is a dir path, save result in assoc array 'dirRollCall'
    # Usage: checkdir arg1 arg2 arg3 ...
    # Version 0.1.1
    # Input: global assoc. array 'dirRollCall'
    # Output: adds/updates key(value) to global assoc array 'dirRollCall';
    # Output: returns 0 if app found, 1 otherwise
    # Depends: Bash 5.0.3
    local returnState

    #===Process Args===
    for arg in "$@"; do
        if [ -d "$arg" ]; then
            dirRollCall["$arg"]="true";
            if ! [ "$returnState" = "false" ]; then returnState="true"; fi
        else
            dirRollCall["$arg"]="false"; returnState="false";
        fi
    done

    #===Determine function return code===
    if [ "$returnState" = "true" ]; then
        return 0;
    else
        return 1;
    fi
} # Check that dir exists
displayMissing() {
    # Desc: Displays missing apps, files, and dirs
    # Usage: displayMissing
    # Version 0.1.1
    # Input: associative arrays: appRollCall, fileRollCall, dirRollCall
    # Output: stderr: messages indicating missing apps, file, or dirs
    # Depends: bash 5, checkAppFileDir()
    local missingApps value appMissing missingFiles fileMissing
    local missingDirs dirMissing

    #==BEGIN Display errors==
    #===BEGIN Display Missing Apps===
    missingApps="Missing apps  :";
    #for key in "${!appRollCall[@]}"; do echo "DEBUG:$key => ${appRollCall[$key]}"; done
    for key in "${!appRollCall[@]}"; do
        value="${appRollCall[$key]}";
        if [ "$value" = "false" ]; then
            #echo "DEBUG:Missing apps: $key => $value";
            missingApps="$missingApps""$key ";
            appMissing="true";
        fi;
    done;
    if [ "$appMissing" = "true" ]; then  # Only indicate if an app is missing.
        echo "$missingApps" 1>&2;
    fi;
    unset value;
    #===END Display Missing Apps===

    #===BEGIN Display Missing Files===
    missingFiles="Missing files:";
    #for key in "${!fileRollCall[@]}"; do echo "DEBUG:$key => ${fileRollCall[$key]}"; done
    for key in "${!fileRollCall[@]}"; do
        value="${fileRollCall[$key]}";
        if [ "$value" = "false" ]; then
            #echo "DEBUG:Missing files: $key => $value";
            missingFiles="$missingFiles""$key ";
            fileMissing="true";
        fi;
    done;
    if [ "$fileMissing" = "true" ]; then  # Only indicate if an app is missing.
        echo "$missingFiles" 1>&2;
    fi;
    unset value;
    #===END Display Missing Files===

    #===BEGIN Display Missing Directories===
    missingDirs="Missing dirs:";
    #for key in "${!dirRollCall[@]}"; do echo "DEBUG:$key => ${dirRollCall[$key]}"; done
    for key in "${!dirRollCall[@]}"; do
        value="${dirRollCall[$key]}";
        if [ "$value" = "false" ]; then
            #echo "DEBUG:Missing dirs: $key => $value";
            missingDirs="$missingDirs""$key ";
            dirMissing="true";
        fi;
    done;
    if [ "$dirMissing" = "true" ]; then  # Only indicate if an dir is missing.
        echo "$missingDirs" 1>&2;
    fi;
    unset value;
    #===END Display Missing Directories===

    #==END Display errors==
} # Display missing apps, files, dirs
check_depends() {
    if ! checkapp mpv parallel bkshuf bc b2sum; then
        displayMissing;
        die "FATAL:Missing apps.";
    fi;
    return 1;
}; # check dependencies
checkInt() {
    # Desc: Checks if arg is integer
    # Usage: checkInt arg
    # Input: arg: integer
    # Output: - return code 0 (if arg is integer)
    #         - return code 1 (if arg is not integer)
    # Example: if ! checkInt $arg; then echo "not int"; fi;
    # Version: 0.0.1
    local returnState

    #===Process Arg===
    if [[ $# -ne 1 ]]; then
        die "ERROR:Invalid number of arguments:$#";
    fi;

    RETEST1='^[0-9]+$'; # Regular Expression to test
    if [[ ! $1 =~ $RETEST1 ]] ; then
        returnState="false";
    else
        returnState="true";
    fi;

    #===Determine function return code===
    if [ "$returnState" = "true" ]; then
        return 0;
    else
        return 1;
    fi;
} # Checks if arg is integer
read_stdin() {
    # Desc: Consumes stdin; outputs as stdout lines
    # Input: stdin (consumes)
    # Output: stdout (newline delimited)
    # Example: printf "foo\nbar\n" | read_stdin
    # Depends: GNU bash (version 5.1.16)
    # Version: 0.0.1
    local input_stdin output;

    # Store stdin
    if [[ -p /dev/stdin ]]; then
        input_stdin="$(cat -)";
    fi;

    # Store as output array elements
    ## Read in stdin
    if [[ -n $input_stdin ]]; then
        while read -r line; do
            output+=("$line");
        done < <(printf "%s\n" "$input_stdin");
    fi;

    # Print to stdout
    printf "%s\n" "${output[@]}";
}; # read stdin to stdout lines
read_psarg() {
    # Desc: Reads arguments; outputs as stdout lines
    # Input: args
    # Output: stdout (newline delimited)
    # Example: read_psarg "$@"
    # Depends: GNU bash (version 5.1.16)
    # Version: 0.0.1
    local input_psarg output;

    # Store arguments
    if [[ $# -gt 0 ]]; then
        input_psarg="$*";
    fi;

    # Store as output array elements
    ## Read in positional arguments
    if [[ -n $input_psarg ]]; then
        for arg in "$@"; do
            output+=("$arg");
        done;
    fi;

    # Print to stdout
    printf "%s\n" "${output[@]}";
}; # read positional argument to stdout lines
find_flist() {
    # Desc: print file list to stdout via `find` using script parameters
    # Input: arg1: path to dir
    #        var: find_depth
    #        var: pattern_find_iregex
    #        var: find_size
    if [[ ! -d "$1" ]]; then return 1; fi;
    must find "$1" -maxdepth "$fdepth" -type f -iregex "$firegex" -size +"$fsize";
}; # print file list to stdout from dir with script parameters
main() {
    # Input: var: firegex     find iregex file name pattern
    #        var: fsize       find minimum file siz
    #        var: fc_falloff  characteristic file count falloff in the output
    #        var: fc_redbase  logarithm base to reduce output file count

    local re_dotfile;
    declare -a files_stdin dirs_stdin dirs_psarg;
    declare -a paths_files;
    declare list_paths_files;
    declare -a cmd_args;
    check_depends;

    yell "STATUS:$SECONDS:Started.";
    #Populate dirs_stdin and dirs_psarg arrays
    ## Read stdin as lines
    re_dotfile="^\."; # first char is a dot
    while read -r line; do
        line="$(readlink -e "$line")";
        line_bn="$(basename "$line")";
        # Check if dir and not dotfile
        if [[ -d "$line" ]] && [[ ! "$line_bn" =~ $re_dotfile ]]; then
            dirs_stdin+=("$line");
            continue;
        fi;

        # Check if file
        if [[ -f "$line" ]]; then
            files_stdin+=("$line");
            continue;
        fi;

        # Throw warning
        yell "WARNING:Not a valid dir or file:$line";
    done < <( read_stdin; read_psarg "$@"; );
    yell "STATUS:$SECONDS:Read stdin and psargs.";

    # Catch all arrays empty
    if [[ "${#dirs_stdin[@]}" -le 0 ]] && \
           [[ "${#dirs_psarg[@]}" -le 0 ]] && \
           [[ "${#files_stdin[@]}" -le 0 ]]; then
        die "FATAL:No valid directories or files provided.";
    fi;

    # Generate file list
    ## Add stdin argument input
    if [[ "${#files_stdin[@]}" -gt 0 ]]; then
        paths_files+=("${files_stdin[@]}");
    fi;

    ## Call find_filelist() in parallel for positional argument input
    if [[ "${#dirs_psarg[@]}" -gt 0 ]]; then
        fdepth="$fdepth_posarg"; export fdepth; # for dirs from positional arguments
        paths_files+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_psarg[@]}" )"); # See [1]
    fi;
    ## Call find_filelist() in parallel for stdin input
    if [[ "${#dirs_stdin[@]}" -gt 0 ]]; then
        fdepth="$fdepth_stdin"; export fdepth; # 1 for dirs from stdin
        paths_files+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_stdin[@]}" )"); # See [1]
    fi;

    # Convert paths_files array into file list
    for i in "${!paths_files[@]}"; do
        list_paths_files="$(printf "%s\n%s" "${paths_files[$i]}" "$list_paths_files")";
    done;
    # Get stats
    fc="$(wc -l < <(echo -n "$list_paths_files"))";
    echo "STATUS:$SECONDS:file count:fc:$fc"
    yell "STATUS:$SECONDS:Generated file list.";

    # Sort, remove duplicate paths
    list_paths_files="$(echo "$list_paths_files" | sort -u | tr -s '\n')";
    yell "STATUS:$SECONDS:Sorted and deduplicated list.";

    # Remove paths with dotfiles
    list_paths_files="$(echo "$list_paths_files" | grep -viE "/\." )";
    yell "STATUS:$SECONDS:Removed dotfiles.";

    # Write playlist
    list_paths_files_tmp="/dev/shm/$(date +%Y%m%dT%H%M%S.%N%z)"..mpv_paths.txt;
    ## Reduce output file count if greater than falloff
    if [[ $fc -gt $fc_falloff ]]; then
            bc_exp="$fc_falloff * (1 + l( $fc / $fc_falloff )/l($fc_redbase))";
            fc_out="$( echo "$bc_exp" | bc -l )";
    else
        fc_out="$fc";
    fi;
    ## Reduce output file count by fixed fraction (bkshuf optimization)
    fc_out="$(echo "$fc_out * 0.75" | bc -l)";
    ## Select subset via bkshuf
    ### Specify bkshuf-specific environment variables
    export BKSHUF_PARAM_LINC=1000000; # for these numbers of lines of input..
    export BKSHUF_PARAM_GSIZE=25;     # target this group size
    ### Round file count down
    fc_out="$(printf "%.0f" "$fc_out")"; # round float down to int
    ### Get neighbor-preserving shuffled subset (size $fc_out)
    yell "STATUS:$SECONDS:Selecting $fc_out of $fc files via bkshuf...";
    must \
        echo -n "$list_paths_files" | \
        bkshuf "$fc_out" > "$list_paths_files_tmp";
    yell "STATUS:$SECONDS:Wrote playlist.";

    # Print stats
    yell "STATUS:$SECONDS:Built file list in $SECONDS seconds.";

    # Run mpv with filelist
    ## Form command
    cmd_args+=("mpv");
    cmd_args+=("--audio-display=no"); # disable video for audio files
    cmd_args+=("--vid=no"); # donʼt show video track
    cmd_args+=("--image-display-duration=0"); # don't show album art
    cmd_args+=("--af=scaletempo=stride=15:overlap=1:search=15"); # improve scrubbing
    cmd_args+=("--playlist=$list_paths_files_tmp"); # read playlist
    declare -p cmd_args; # debug
    ## Execute command
    must "${cmd_args[@]}";
    must rm "$list_paths_files_tmp";
};
export -f yell die must read_stdin read_psarg find_flist;

main "$@";

# Author: Steven Baltakatei Sandoval
# License: GPLv3+
Commit	Line	Data
75e92939	1	#!/usr/bin/env bash
75baf701	2	# Desc: Wrapper for mpv that accepts directory or file paths via posargs or stdin lines
75e92939	3	# Usage: bkmpv2 [DIR]
75baf701	4	# Version: 0.1.0
75e92939 SBS	5	# Depends: GNU Parallel, GNU Bash v5.1.16, mpv v0.34.1, bc v1.07.1
	6	# Ref/Attrib: [1] Tange, Ole. GNU Parallel with Bash Array. 2019-03-24. https://unix.stackexchange.com/a/508365/411854
	7	# Example: find $HOME/Music -type d \| bkmpv2
	8	# Example: bkmpv2 $HOME/Music/
75baf701	9	# Example: find $HOME -type f -name "*.mp3" \| bkmpv2
75e92939 SBS	10	# Note: Does not follow symlinks
	11
	12	# Find settings
	13	firegex=".+\(aac\\|aif\\|aiff\\|flac\\|m4a\\|mp3\\|mp4\\|ogg\\|opus\\|wav\)$"; # update according to `find . -type f \| grep -Eo "\.([[:alnum:]])+$" \| sort -u`
	14	fsize="10k"; # default: minimum "10k"
	15	fdepth_posarg="10"; # find depth for positional arguments
	16	fdepth_stdin="1"; # find depth for stdin
	17	fc_falloff="1000"; # characteristic file count falloff in the output
	18	fc_redbase="10"; # logarithm base to reduce output file count
	19
	20	export firegex fsize ; # export for parallel
	21
	22	#===Declare local functions===
	23	yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
	24	die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
	25	must() { "$@" \|\| die "cannot $*"; } # runs args as command, reports args if command fails
	26	checkapp() {
	27	# Desc: If arg is a command, save result in assoc array 'appRollCall'
	28	# Usage: checkapp arg1 arg2 arg3 ...
	29	# Version: 0.1.1
	30	# Input: global assoc. array 'appRollCall'
	31	# Output: adds/updates key(value) to global assoc array 'appRollCall'
	32	# Depends: bash 5.0.3
75baf701	33	local returnState
75e92939 SBS	34
	35	#===Process Args===
	36	for arg in "$@"; do
75baf701 SBS	37	if command -v "$arg" 1>/dev/null 2>&1; then # Check if arg is a valid command
	38	appRollCall[$arg]="true";
	39	if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
	40	else
	41	appRollCall[$arg]="false"; returnState="false";
	42	fi;
75e92939 SBS	43	done;
	44
	45	#===Determine function return code===
	46	if [ "$returnState" = "true" ]; then
75baf701	47	return 0;
75e92939	48	else
75baf701	49	return 1;
75e92939 SBS	50	fi;
	51	} # Check that app exists
	52	checkfile() {
	53	# Desc: If arg is a file path, save result in assoc array 'fileRollCall'
	54	# Usage: checkfile arg1 arg2 arg3 ...
	55	# Version: 0.1.1
	56	# Input: global assoc. array 'fileRollCall'
	57	# Output: adds/updates key(value) to global assoc array 'fileRollCall';
	58	# Output: returns 0 if app found, 1 otherwise
	59	# Depends: bash 5.0.3
	60	local returnState
	61
	62	#===Process Args===
	63	for arg in "$@"; do
75baf701 SBS	64	if [ -f "$arg" ]; then
	65	fileRollCall["$arg"]="true";
	66	if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
	67	else
	68	fileRollCall["$arg"]="false"; returnState="false";
	69	fi;
75e92939	70	done;
75baf701	71
75e92939 SBS	72	#===Determine function return code===
75e92939 SBS	73	if [ "$returnState" = "true" ]; then
75baf701	74	return 0;
75e92939	75	else
75baf701	76	return 1;
75e92939 SBS	77	fi;
	78	} # Check that file exists
	79	checkdir() {
	80	# Desc: If arg is a dir path, save result in assoc array 'dirRollCall'
	81	# Usage: checkdir arg1 arg2 arg3 ...
	82	# Version 0.1.1
	83	# Input: global assoc. array 'dirRollCall'
	84	# Output: adds/updates key(value) to global assoc array 'dirRollCall';
	85	# Output: returns 0 if app found, 1 otherwise
	86	# Depends: Bash 5.0.3
	87	local returnState
	88
	89	#===Process Args===
	90	for arg in "$@"; do
75baf701 SBS	91	if [ -d "$arg" ]; then
	92	dirRollCall["$arg"]="true";
	93	if ! [ "$returnState" = "false" ]; then returnState="true"; fi
	94	else
	95	dirRollCall["$arg"]="false"; returnState="false";
	96	fi
75e92939	97	done
75baf701	98
75e92939 SBS	99	#===Determine function return code===
75e92939 SBS	100	if [ "$returnState" = "true" ]; then
75baf701	101	return 0;
75e92939	102	else
75baf701	103	return 1;
75e92939 SBS	104	fi
	105	} # Check that dir exists
	106	displayMissing() {
	107	# Desc: Displays missing apps, files, and dirs
	108	# Usage: displayMissing
	109	# Version 0.1.1
	110	# Input: associative arrays: appRollCall, fileRollCall, dirRollCall
	111	# Output: stderr: messages indicating missing apps, file, or dirs
	112	# Depends: bash 5, checkAppFileDir()
	113	local missingApps value appMissing missingFiles fileMissing
	114	local missingDirs dirMissing
75baf701	115
75e92939 SBS	116	#==BEGIN Display errors==
	117	#===BEGIN Display Missing Apps===
	118	missingApps="Missing apps :";
	119	#for key in "${!appRollCall[@]}"; do echo "DEBUG:$key => ${appRollCall[$key]}"; done
	120	for key in "${!appRollCall[@]}"; do
75baf701 SBS	121	value="${appRollCall[$key]}";
	122	if [ "$value" = "false" ]; then
	123	#echo "DEBUG:Missing apps: $key => $value";
	124	missingApps="$missingApps""$key ";
	125	appMissing="true";
	126	fi;
75e92939 SBS	127	done;
75e92939 SBS	128	if [ "$appMissing" = "true" ]; then # Only indicate if an app is missing.
75baf701	129	echo "$missingApps" 1>&2;
75e92939 SBS	130	fi;
	131	unset value;
	132	#===END Display Missing Apps===
	133
	134	#===BEGIN Display Missing Files===
	135	missingFiles="Missing files:";
	136	#for key in "${!fileRollCall[@]}"; do echo "DEBUG:$key => ${fileRollCall[$key]}"; done
	137	for key in "${!fileRollCall[@]}"; do
75baf701 SBS	138	value="${fileRollCall[$key]}";
	139	if [ "$value" = "false" ]; then
	140	#echo "DEBUG:Missing files: $key => $value";
	141	missingFiles="$missingFiles""$key ";
	142	fileMissing="true";
	143	fi;
75e92939 SBS	144	done;
75e92939 SBS	145	if [ "$fileMissing" = "true" ]; then # Only indicate if an app is missing.
75baf701	146	echo "$missingFiles" 1>&2;
75e92939 SBS	147	fi;
	148	unset value;
	149	#===END Display Missing Files===
	150
	151	#===BEGIN Display Missing Directories===
	152	missingDirs="Missing dirs:";
	153	#for key in "${!dirRollCall[@]}"; do echo "DEBUG:$key => ${dirRollCall[$key]}"; done
	154	for key in "${!dirRollCall[@]}"; do
75baf701 SBS	155	value="${dirRollCall[$key]}";
	156	if [ "$value" = "false" ]; then
	157	#echo "DEBUG:Missing dirs: $key => $value";
	158	missingDirs="$missingDirs""$key ";
	159	dirMissing="true";
	160	fi;
75e92939 SBS	161	done;
75e92939 SBS	162	if [ "$dirMissing" = "true" ]; then # Only indicate if an dir is missing.
75baf701	163	echo "$missingDirs" 1>&2;
75e92939 SBS	164	fi;
	165	unset value;
	166	#===END Display Missing Directories===
	167
	168	#==END Display errors==
	169	} # Display missing apps, files, dirs
	170	check_depends() {
	171	if ! checkapp mpv parallel bkshuf bc b2sum; then
	172	displayMissing;
	173	die "FATAL:Missing apps.";
	174	fi;
	175	return 1;
	176	}; # check dependencies
	177	checkInt() {
	178	# Desc: Checks if arg is integer
	179	# Usage: checkInt arg
	180	# Input: arg: integer
	181	# Output: - return code 0 (if arg is integer)
	182	# - return code 1 (if arg is not integer)
	183	# Example: if ! checkInt $arg; then echo "not int"; fi;
	184	# Version: 0.0.1
	185	local returnState
	186
	187	#===Process Arg===
	188	if [[ $# -ne 1 ]]; then
75baf701	189	die "ERROR:Invalid number of arguments:$#";
75e92939	190	fi;
75baf701	191
75e92939 SBS	192	RETEST1='^[0-9]+$'; # Regular Expression to test
75e92939 SBS	193	if [[ ! $1 =~ $RETEST1 ]] ; then
75baf701	194	returnState="false";
75e92939	195	else
75baf701	196	returnState="true";
75e92939 SBS	197	fi;
	198
	199	#===Determine function return code===
	200	if [ "$returnState" = "true" ]; then
75baf701	201	return 0;
75e92939	202	else
75baf701	203	return 1;
75e92939 SBS	204	fi;
	205	} # Checks if arg is integer
	206	read_stdin() {
	207	# Desc: Consumes stdin; outputs as stdout lines
	208	# Input: stdin (consumes)
	209	# Output: stdout (newline delimited)
	210	# Example: printf "foo\nbar\n" \| read_stdin
	211	# Depends: GNU bash (version 5.1.16)
	212	# Version: 0.0.1
	213	local input_stdin output;
	214
	215	# Store stdin
	216	if [[ -p /dev/stdin ]]; then
	217	input_stdin="$(cat -)";
75baf701 SBS	218	fi;
75baf701 SBS	219
75e92939 SBS	220	# Store as output array elements
	221	## Read in stdin
	222	if [[ -n $input_stdin ]]; then
	223	while read -r line; do
	224	output+=("$line");
	225	done < <(printf "%s\n" "$input_stdin");
	226	fi;
	227
	228	# Print to stdout
	229	printf "%s\n" "${output[@]}";
	230	}; # read stdin to stdout lines
	231	read_psarg() {
	232	# Desc: Reads arguments; outputs as stdout lines
	233	# Input: args
	234	# Output: stdout (newline delimited)
	235	# Example: read_psarg "$@"
	236	# Depends: GNU bash (version 5.1.16)
	237	# Version: 0.0.1
	238	local input_psarg output;
75baf701	239
75e92939 SBS	240	# Store arguments
	241	if [[ $# -gt 0 ]]; then
	242	input_psarg="$*";
	243	fi;
75baf701	244
75e92939 SBS	245	# Store as output array elements
	246	## Read in positional arguments
	247	if [[ -n $input_psarg ]]; then
	248	for arg in "$@"; do
	249	output+=("$arg");
	250	done;
	251	fi;
	252
	253	# Print to stdout
	254	printf "%s\n" "${output[@]}";
	255	}; # read positional argument to stdout lines
	256	find_flist() {
	257	# Desc: print file list to stdout via `find` using script parameters
	258	# Input: arg1: path to dir
	259	# var: find_depth
	260	# var: pattern_find_iregex
	261	# var: find_size
	262	if [[ ! -d "$1" ]]; then return 1; fi;
	263	must find "$1" -maxdepth "$fdepth" -type f -iregex "$firegex" -size +"$fsize";
	264	}; # print file list to stdout from dir with script parameters
	265	main() {
	266	# Input: var: firegex find iregex file name pattern
	267	# var: fsize find minimum file siz
	268	# var: fc_falloff characteristic file count falloff in the output
	269	# var: fc_redbase logarithm base to reduce output file count
	270
	271	local re_dotfile;
75baf701	272	declare -a files_stdin dirs_stdin dirs_psarg;
75e92939 SBS	273	declare -a paths_files;
	274	declare list_paths_files;
	275	declare -a cmd_args;
	276	check_depends;
	277
	278	yell "STATUS:$SECONDS:Started.";
	279	#Populate dirs_stdin and dirs_psarg arrays
	280	## Read stdin as lines
	281	re_dotfile="^\."; # first char is a dot
	282	while read -r line; do
	283	line="$(readlink -e "$line")";
75baf701 SBS	284	line_bn="$(basename "$line")";
	285	# Check if dir and not dotfile
	286	if [[ -d "$line" ]] && [[ ! "$line_bn" =~ $re_dotfile ]]; then
	287	dirs_stdin+=("$line");
75e92939 SBS	288	continue;
75e92939 SBS	289	fi;
75baf701 SBS	290
	291	# Check if file
	292	if [[ -f "$line" ]]; then
	293	files_stdin+=("$line");
75e92939 SBS	294	continue;
75e92939 SBS	295	fi;
75baf701 SBS	296
	297	# Throw warning
	298	yell "WARNING:Not a valid dir or file:$line";
	299	done < <( read_stdin; read_psarg "$@"; );
	300	yell "STATUS:$SECONDS:Read stdin and psargs.";
	301
75e92939	302	# Catch all arrays empty
75baf701 SBS	303	if [[ "${#dirs_stdin[@]}" -le 0 ]] && \
	304	[[ "${#dirs_psarg[@]}" -le 0 ]] && \
	305	[[ "${#files_stdin[@]}" -le 0 ]]; then
	306	die "FATAL:No valid directories or files provided.";
75e92939 SBS	307	fi;
	308
	309	# Generate file list
75baf701 SBS	310	## Add stdin argument input
	311	if [[ "${#files_stdin[@]}" -gt 0 ]]; then
	312	paths_files+=("${files_stdin[@]}");
	313	fi;
	314
75e92939 SBS	315	## Call find_filelist() in parallel for positional argument input
	316	if [[ "${#dirs_psarg[@]}" -gt 0 ]]; then
	317	fdepth="$fdepth_posarg"; export fdepth; # for dirs from positional arguments
	318	paths_files+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_psarg[@]}" )"); # See [1]
	319	fi;
	320	## Call find_filelist() in parallel for stdin input
	321	if [[ "${#dirs_stdin[@]}" -gt 0 ]]; then
	322	fdepth="$fdepth_stdin"; export fdepth; # 1 for dirs from stdin
	323	paths_files+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_stdin[@]}" )"); # See [1]
	324	fi;
	325
	326	# Convert paths_files array into file list
	327	for i in "${!paths_files[@]}"; do
	328	list_paths_files="$(printf "%s\n%s" "${paths_files[$i]}" "$list_paths_files")";
	329	done;
	330	# Get stats
	331	fc="$(wc -l < <(echo -n "$list_paths_files"))";
	332	echo "STATUS:$SECONDS:file count:fc:$fc"
	333	yell "STATUS:$SECONDS:Generated file list.";
	334
	335	# Sort, remove duplicate paths
	336	list_paths_files="$(echo "$list_paths_files" \| sort -u \| tr -s '\n')";
	337	yell "STATUS:$SECONDS:Sorted and deduplicated list.";
	338
	339	# Remove paths with dotfiles
	340	list_paths_files="$(echo "$list_paths_files" \| grep -viE "/\." )";
	341	yell "STATUS:$SECONDS:Removed dotfiles.";
	342
	343	# Write playlist
	344	list_paths_files_tmp="/dev/shm/$(date +%Y%m%dT%H%M%S.%N%z)"..mpv_paths.txt;
	345	## Reduce output file count if greater than falloff
	346	if [[ $fc -gt $fc_falloff ]]; then
	347	bc_exp="$fc_falloff * (1 + l( $fc / $fc_falloff )/l($fc_redbase))";
	348	fc_out="$( echo "$bc_exp" \| bc -l )";
	349	else
75baf701	350	fc_out="$fc";
75e92939 SBS	351	fi;
	352	## Reduce output file count by fixed fraction (bkshuf optimization)
	353	fc_out="$(echo "$fc_out * 0.75" \| bc -l)";
	354	## Select subset via bkshuf
	355	### Specify bkshuf-specific environment variables
	356	export BKSHUF_PARAM_LINC=1000000; # for these numbers of lines of input..
	357	export BKSHUF_PARAM_GSIZE=25; # target this group size
	358	### Round file count down
	359	fc_out="$(printf "%.0f" "$fc_out")"; # round float down to int
	360	### Get neighbor-preserving shuffled subset (size $fc_out)
75baf701	361	yell "STATUS:$SECONDS:Selecting $fc_out of $fc files via bkshuf...";
75e92939 SBS	362	must \
	363	echo -n "$list_paths_files" \| \
	364	bkshuf "$fc_out" > "$list_paths_files_tmp";
	365	yell "STATUS:$SECONDS:Wrote playlist.";
	366
	367	# Print stats
	368	yell "STATUS:$SECONDS:Built file list in $SECONDS seconds.";
	369
	370	# Run mpv with filelist
	371	## Form command
	372	cmd_args+=("mpv");
	373	cmd_args+=("--audio-display=no"); # disable video for audio files
	374	cmd_args+=("--vid=no"); # donʼt show video track
	375	cmd_args+=("--image-display-duration=0"); # don't show album art
	376	cmd_args+=("--af=scaletempo=stride=15:overlap=1:search=15"); # improve scrubbing
	377	cmd_args+=("--playlist=$list_paths_files_tmp"); # read playlist
	378	declare -p cmd_args; # debug
	379	## Execute command
	380	must "${cmd_args[@]}";
	381	must rm "$list_paths_files_tmp";
	382	};
	383	export -f yell die must read_stdin read_psarg find_flist;
	384
	385	main "$@";
	386
	387	# Author: Steven Baltakatei Sandoval
	388	# License: GPLv3+