#!/usr/bin/env bash
# Desc: Wrapper for mpv that accepts directory paths via posargs or stdin lines
# Usage: bkmpv2 [DIR]
# Version: 0.0.1
# 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/
# 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 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 "$line")";
# Check if dir
if [[ ! -d "$line" ]]; then
echo "ERROR:Not a dir:$line" 1>&2;
continue;
fi;
dir_name="$(basename "$line")";
# Exclude dotdirs
if [[ "$dir_name" =~ $re_dotfile ]]; then
echo "ERROR:Is a dotdir:$line" 1>&2;
continue
fi;
dirs_stdin+=("$line");
done < <(read_stdin);
yell "STATUS:$SECONDS:Read stdin.";
## Read positional arguments as lines
re_dotfile="^\."; # first char is a dot
while read -r line; do
line="$(readlink -e "$line")";
# Check if dir
if [[ ! -d "$line" ]]; then
echo "ERROR:Not a dir:$line" 1>&2;
continue;
fi;
dir_name="$(basename "$line")";
# Exclude dotdirs
if [[ "$dir_name" =~ $re_dotfile ]]; then
echo "ERROR:Is a dotdir:$line" 1>&2;
continue
fi;
dirs_psarg+=("$line");
done < <(read_psarg "$@");
yell "STATUS:$SECONDS:Read posargs.";
# Catch all arrays empty
if [[ "${#dirs_stdin[@]}" -le 0 ]] && [[ "${#dirs_psarg[@]}" -le 0 ]]; then
die "FATAL:No valid directories provided.";
fi;
# Generate file list
## Call find_filelist() in parallel for positional argument input
if [[ "${#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 $fc_out files via bkshuf...";
must \
echo -n "$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+