+#!/usr/bin/env bash
+# Desc: Copies random music
+# Usage: bk-copy-rand-music.sh [dir SOURCE] [dir DEST] [int DURATION]
+
+declare -Ag appRollCall # Associative array for storing app status
+declare -Ag fileRollCall # Associative array for storing file status
+declare -Ag dirRollCall # Associative array for storing dir status
+declare -a music_codecs # Array for storing valid codec names (e.g. "aac" "mp3")
+
+# Adjustable parameters
+music_codecs=("vorbis" "aac" "mp3" "flac" "opus"); # whitelist of valid codec_names ffprobe might return
+max_loops=1000000; # max number of files to test whether are audio or not
+
+yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
+die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
+try() { "$@" || 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 [ "$returnState" = "true" ]; then
+ return 0;
+ else
+ return 1;
+ fi;
+} # Check that file exists
+checkdir() {
+ # Desc: If arg is a dir path, save result in assoc array 'dirRollCall'
+ # Usage: checkdir arg1 arg2 arg3 ...
+ # Version 0.1.2
+ # Input: global assoc. array 'dirRollCall'
+ # Output: adds/updates key(value) to global assoc array 'dirRollCall';
+ # Output: returns 0 if all args are dirs; 1 otherwise
+ # Depends: Bash 5.0.3
+ local returnState
+
+ #===Process Args===
+ for arg in "$@"; do
+ if [ -z "$arg" ]; then
+ dirRollCall["(Unspecified Dirname(s))"]="false"; returnState="false";
+ elif [ -d "$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 1.0.0
+ # Input: associative arrays: appRollCall, fileRollCall, dirRollCall
+ # Output: stderr: messages indicating missing apps, file, or dirs
+ # Output: returns exit code 0 if nothing missing; 1 otherwise
+ # 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 "$missingDirs" 1>&2;
+ fi;
+ unset value;
+ #===END Display Missing Directories===
+
+ #==END Display errors==
+ #==BEGIN Determine function return code===
+ if [ "$appMissing" == "true" ] || [ "$fileMissing" == "true" ] || [ "$dirMissing" == "true" ]; then
+ return 1;
+ else
+ return 0;
+ fi
+ #==END Determine function return code===
+} # Display missing apps, files, dirs
+showUsage() {
+ # Desc: Display script usage information
+ # Usage: showUsage
+ # Version 0.0.1
+ # Input: none
+ # Output: stdout
+ # Depends: GNU-coreutils 8.30 (cat)
+ cat <<'EOF'
+
+ DESCRIPTION:
+ This script may be used to copy a random selection of files from
+ SOURCE to DEST.
+
+ USAGE:
+ bk-copy-rand-music [dir SOURCE] [dir DEST] [int DURATION]
+
+ EXAMPLE:
+ bk-copy-rand-music ~/Music /tmp/music-sample 3600
+
+ DEPENDENCIES:
+ ffprobe
+ GNU Coreutils 8.30
+EOF
+} # Display information on how to use this script.
+check_parsable_audio_ffprobe() {
+ # Desc: Checks if ffprobe returns valid audio codec name for file
+ # Usage: check_parsable_audio_ffprobe [path FILE]
+ # Version: 0.0.1
+ # Input: arg1: file path
+ # Output: exit code 0 if returns valid codec name; 1 otherwise
+ # Depends: ffprobe, die()
+ local file_in ffprobe_out
+
+ if [[ $# -ne 1 ]]; then die "ERROR:Invalid number of args:$#"; fi;
+
+ file_in="$1";
+
+ # Check if ffprobe detects an audio stream
+ if ffprobe -v error -select_streams a -show_entries stream=codec_name -of default=nokey=1:noprint_wrappers=1 "$file_in" 1>/dev/null 2>&1; then
+ return_state="true";
+ else
+ return_state="false";
+ fi;
+
+ # Fail if ffprobe returns no result
+ ffprobe_out="$(ffprobe -v error -select_streams a -show_entries stream=codec_name -of default=nokey=1:noprint_wrappers=1 "$file_in")";
+ if [[ -z $ffprobe_out ]]; then
+ return_state="false";
+ fi;
+
+ # Report exit code
+ if [[ $return_state = "true" ]]; then
+ return 0;
+ else
+ return 1;
+ fi;
+} # Checks if file has valid codec name using ffprobe
+get_audio_format() {
+ # Desc: Gets audio format of file as string
+ # Usage: get_audio_format arg1
+ # Depends: ffprobe
+ # Version: 0.0.1
+ # Input: arg1: input file path
+ # Output: stdout (if valid audio format)
+ # exit code 0 if audio file; 1 otherwise
+ # Example: get_audio_format myvideo.mp4
+ # Note: Would return "opus" if full ffprobe report had 'Audio: opus, 48000 Hz, stereo, fltp'
+ # Note: Not tested with videos containing multiple video streams
+ # Ref/Attrib: [1] https://stackoverflow.com/questions/5618363/is-there-a-way-to-use-ffmpeg-to-determine-the-encoding-of-a-file-before-transcod
+ # [2] https://stackoverflow.com/questions/44123532/how-to-find-out-the-file-extension-for-extracting-audio-tracks-with-ffmpeg-and-p#comment88464070_50723126
+ local audio_format file_in;
+ local return_state;
+ file_in="$1";
+
+ # Return error exit code if not audio file
+ ## Return error if ffprobe itself exited on error
+ if ! ffprobe -v error -select_streams a -show_entries stream=codec_name -of default=nokey=1:noprint_wrappers=1 "$file_in" 1>/dev/null 2>&1; then
+ return_state="false";
+ fi;
+
+ # Get audio format
+ audio_format="$(ffprobe -v error -select_streams a -show_entries stream=codec_name -of default=nokey=1:noprint_wrappers=1 "$file_in")"; # see [1]
+
+ ## Return error if audio format is incorrectly formatted (e.g. reject if contains spaces)
+ pattern="^[[:alnum:]]+$"; # alphanumeric string with no spaces
+ if [[ $audio_format =~ $pattern ]]; then
+ return_state="true";
+ # Report audio format
+ echo "$audio_format";
+ else
+ return_state="false";
+ fi;
+
+ # Report exit code
+ if [[ $return_state = "true" ]]; then
+ return 0;
+ else
+ return 1;
+ fi;
+} # Get audio format as stdout
+get_media_length() {
+ # Use ffprobe to get media container length in seconds (float)
+ # Usage: get_media_length arg1
+ # Input: arg1: path to file
+ # Output: stdout: seconds (float)
+ # Depends: ffprobe 4.1.8
+ # Ref/Attrib: [1] How to get video duration in seconds? https://superuser.com/a/945604
+ local file_in
+ file_in="$1";
+ if [[ ! -f $file_in ]]; then
+ die "ERROR:Not a file:$file_in";
+ fi;
+ ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 "$file_in";
+} # Get media container length in seconds via stdout
+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
+checkIsInArray() {
+ # Desc: Checks if input arg is element in array
+ # Usage: checkIsInArray arg1 arg2
+ # Version: 0.0.1
+ # Input: arg1: test string
+ # arg2: array
+ # Output: exit code 0 if test string is in array; 1 otherwise
+ # Example: checkIsInArray "foo" "${myArray[@]}"
+ # Ref/Attrib: [1] How do I check if variable is an array? https://stackoverflow.com/a/27254437
+ # [2] How to pass an array as function argument? https://askubuntu.com/a/674347
+ local return_state input arg1 string_test
+ declare -a arg2 array_test
+ input=("$@") # See [2]
+ arg1="${input[0]}";
+ arg2=("${input[@]:1}");
+ #yell "DEBUG:input:${input[@]}";
+ #yell "DEBUG:arg1:${arg1[@]}";
+ #yell "DEBUG:arg2:${arg2[@]}";
+
+ string_test="$arg1";
+ array_test=("${arg2[@]}");
+
+ #yell "DEBUG:string_test:$string_test";
+ #yell "DEBUG:$(declare -p array_test)";
+ for element in "${array_test[@]}"; do
+ #yell "DEBUG:element:$element";
+ if [[ "$element" =~ ^"$string_test" ]]; then
+ return_state="true";
+ continue;
+ fi;
+ done;
+
+ # Report exit code
+ if [[ $return_state == "true" ]]; then
+ return 0;
+ else
+ return 1;
+ fi;
+} # Check if string is element in array
+main() {
+ # Desc: Main program
+ # Input: arg1: path to source tree
+ # arg2: path to destination tree
+ # arg3: cumulative duration (seconds) of audio files in destination tree
+ # assoc arrays: appRollCall, fileRollCall, dirRollCall
+ # Output: [none]
+ # Depends: yell(), checkdir() 0.1.2, displayMissing() 1.0.0, GNU Coreutils 8.30 (shuf)
+ local arg1 arg2 arg3 dur_dest dir_source dir_dest list_all
+ declare -a list_files # array for files to be considered
+ declare -A list_copy # assoc array for files to be copied (key=path; value=duration)
+
+ # Parse args
+ arg1="$1";
+ arg2="$2";
+ arg3="$3";
+ if [[ $# -ne 3 ]]; then showUsage; die "ERROR:Invalid number of args."; fi;
+
+ ## Check duration
+ if checkInt "$arg3"; then
+ dur_dest="$arg3";
+ else
+ yell "ERROR:Duration (seconds) not an int:$arg3"
+ fi;
+
+ ## Check directories
+ if checkdir "$arg1" "$arg2"; then
+ dir_source="$arg1";
+ dir_dest="$arg2";
+ else
+ yell "ERROR:Directory error";
+ fi;
+
+ ## Check apps
+ checkapp ffprobe;
+
+ if ! displayMissing; then
+ showUsage;
+ die "ERROR:Check missing resources.";
+ fi;
+
+ yell "STATUS:Working...";
+
+ # Generate file path list
+ list_all="$(find -L "$dir_source")";
+ #yell "DEBUG:list_files_rel:$list_files_rel";
+
+ # Prune list_all of non-files and save as array list_files
+ while read -r line; do
+ #yell "DEBUG:line:$line";
+ if ! [[ -f $line ]]; then
+ #yell "DEBUG:Not a file:$line";
+ #yell ""; # debug
+ continue;
+ fi;
+ list_files+=("$line");
+ done < <(echo "$list_all");
+
+ # Randomly test and add elements of list_files array to list_copy
+ dur=0; # Initialize duration
+ n=0; # Initialize loop counter
+ ## Get element count of list_files array
+ list_files_count="${#list_files[@]}";
+ while [[ $dur -le $dur_dest ]]; do
+ #yell "DEBUG:list_copy building loop:$n";
+ ### Select random element of list_files array
+ list_files_index="$(shuf -i 1-"$list_files_count" -n1)";
+ list_files_index="$((list_files_index - 1))"; # bash arrays are zero-indexed
+ path_candfile="${list_files[$list_files_index]}"; # path of candidate file
+
+ ### Check if has valid codec
+ if ! check_parsable_audio_ffprobe "$path_candfile"; then continue; fi; # reject
+
+ ### Check if desired codec
+ file_format="$(get_audio_format "$path_candfile")";
+ if ! checkIsInArray "$file_format" "${music_codecs[@]}"; then continue; fi; # reject
+
+ ### Check and save duration
+ dur_cand="$(get_media_length "$path_candfile")";
+ dur_cand="${dur_cand%%.*}"; # convert float to int
+ if ! checkInt "$dur_cand"; then continue; fi; # reject
+
+ ### Add/update candfile to list_copy assoc. array (key=path; value=duration)
+ #yell "DEBUG:Adding $path_candfile";
+ list_copy["$path_candfile"]="$dur_cand";
+
+ ### Update total duration $dur by summing all list_copy assoc. array values
+ dur=0;
+ for value in "${list_copy[@]}"; do
+ dur="$((dur + value))";
+ done;
+ #yell "DEBUG:dur:$dur";
+
+ ### Sanity check
+ ((n++));
+ if [[ $n -gt $max_loops ]]; then die "ERROR:Too many loops:$n"; fi;
+ done;
+
+ # Copy files in list_copy to dir_dest;
+ for key in "${!list_copy[@]}"; do
+ value="${list_copy[$key]}";
+ ## Get basename of path
+ file_basename="$(basename "$key")";
+
+ ## Get 16-character b2sum fingerprint (for different files that share basename)
+ fingerprint="$(b2sum -l64 "$key" | cut -d' ' -f1)";
+
+ ## Form output path
+ path_output="$dir_dest"/"$fingerprint".."$file_basename";
+
+ ## Copy
+ try cp "$key" "$path_output" && yell "NOTICE:Copied ($value seconds): $key ";
+ #yell "DEBUG:Copied $file_basename to $dur_dest.";
+
+ unset file_basename path_output
+ done;
+
+ # Report total duration
+ yell "NOTICE:Total duration (seconds):$dur";
+
+} # Main program
+
+main "$@";
+
+# Author: Steven Baltakatei Sandoval
+# License: GPLv3+
projects / BK-2020-03.git / commitdiff