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

#!/usr/bin/env bash
# Desc: Wrapper for feh that accepts directory paths via posargs or stdin lines.
# Version: 0.2.0
# Ref/Attrib: [1] Tange, Ole. GNU Parallel with Bash Array. 2019-03-24. https://unix.stackexchange.com/a/508365/411854
# Depends: GNU Parallel, GNU Bash v5.1.16, feh 3.6.3

#===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 feh parallel; 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
save_sample() {
    # Usage: save_sample arg1
    # Input: arg1   list_paths        (list of files to take samples from)
    #        envvar BKFEH_SAMPLE_DIR  (environment variable set outside of this script)
    #        envvar BKFEH_SAMPLE_SIZE (space limit for sample dir files)
    # Depends: yell(), GNU Parallel, GNU find, GNU Coreutils 8.32 (cut, find, du)
    local list_paths
    sample_count="100"; # max number of images to put in sample dir
    sample_max_space="10000000"; # max bytes to put in sample dir

    # Load environment variables if set
    if [[ ! -v BKFEH_SAMPLE_DIR ]]; then return 0; fi; # return early if environment var not set.
    if [[ -v BKFEH_SAMPLE_SIZE ]] && checkInt "$BKFEH_SAMPLE_SIZE"; then
        sample_max_space="$BKFEH_SAMPLE_SIZE";
    fi;
    if [[ -v BKFEH_SAMPLE_COUNT ]] && checkInt "$BKFEH_SAMPLE_COUNT"; then
        sample_count="$BKFEH_SAMPLE_COUNT";
    fi;
    
    if [[ ! -z "$1" ]]; then
        list_paths="$1"; # newline-delimited list of file paths to sample from
    else
        yell "ERROR:NO paths available to sample.";
    fi;
    
    if [[ -d "$BKFEH_SAMPLE_DIR" ]]; then
        sample_dir="$BKFEH_SAMPLE_DIR";
        yell "STATUS:Environment variable BKFEH_SAMPLE_DIR set. Clearing and saving samples...";
        
        ## clear previous sample
        count_samples="$(find $BKFEH_SAMPLE_DIR -maxdepth 1 -type f | wc -l)";
        find "$BKFEH_SAMPLE_DIR" -maxdepth 1 -type f -exec rm '{}' \; ;
        
        ## save random sample
        yell "STATUS:Saving random sample of size $sample_count to $BKFEH_SAMPLE_DIR...";
        list_paths_sample="$(echo "$list_paths" | shuf | head -n"$sample_count")";
        while read -r line; do
            if [[ -z "$line" ]]; then continue; fi;
            ### check size limit
            sample_act_space="$(du -bd1 "$BKFEH_SAMPLE_DIR" | cut -f1 )"; # actual used space
            cand_space="$(du -bd1 "$line" | cut -f1 )"; # size of candidate file to add
            sample_req_space="$((sample_act_space + cand_space))";
            if [[ "$sample_req_space" -lt "$sample_max_space" ]]; then
                #### add file to sample dir
                cp -n "$line" "$BKFEH_SAMPLE_DIR" ;
            fi;
        done < <( echo "$list_paths_sample" );
    else
        yell "ERROR:Does not exist: $BKFEH_SAMPLE_DIR";
    fi;    
}; # save sample of files

main() {
    # Depends: read_stdin_psarg() v0.0.1, check_depends()
    local re_dotfile;
    declare -a dirs_stdin dirs_psarg;
    declare -a paths_images;
    declare list_paths_images;
    check_depends;

    #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+=("$line");
    done < <(read_stdin);
    ## Read positional arguments as lines
    re_dotfile="^\."; # first char is a dot
    while read -r line; do
        line="$(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+=("$line");
    done < <(read_psarg "$@");
    
    # Catch all arrays empty
    if [[ "${#dirs_stdin[@]}" -le 0 ]] && [[ "${#dirs_psarg[@]}" -le 0 ]]; then
        die "FATAL:No valid directories provided.";
    fi;
    
    # Generate file list
    # Find settings
    firegex=".+\(jpg\|jpeg\|gif\|png\|webm\)$"; # update according to `find . -type f | grep -Eo "\.([[:alnum:]])+$" | sort -u`
    fsize="10k"; # default: minimum "10k"
    export firegex fsize ; # export for parallel
    ## Call find_filelist() in parallel for positional argument input
    if [[ "${#dirs_psarg[@]}" -gt 0 ]]; then
        fdepth=10; export fdepth; # 10 for dirs from positional arguments
        paths_images+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_psarg[@]}" )"); # See [1]
    fi;
    ## Call find_filelist() in parallel for stdin input
    if [[ "${#dirs_stdin[@]}" -gt 0 ]]; then
        fdepth=1; export fdepth; # 1 ofr dirs from stdin
        paths_images+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_stdin[@]}" )"); # See [1]
    fi;
    
    # Convert paths_images array into file list
    for i in "${!paths_images[@]}"; do
        list_paths_images="$(printf "%s\n%s" "${paths_images[$i]}" "$list_paths_images")";

        # Get stats
        file_count="$(wc -l < <(echo -n "$list_paths_images"))";
        echo "$DEBUG:file_count:$file_count"
    done;
    
    # Sort, remove duplicate paths
    list_paths_images="$(echo "$list_paths_images" | sort -u | tr -s '\n')";

    # Remove paths with dotfiles
    list_paths_images="$(echo "$list_paths_images" | grep -viE "/\." )";

    # Write
    list_paths_images_tmp="/dev/shm/$(date +%Y%m%dT%H%M%S.%N%z)"..feh_paths.txt;
    must echo -n "$list_paths_images" > "$list_paths_images_tmp";

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

    # Run feh with filelist
    feh --full-screen --auto-zoom --draw-filename --filelist "$list_paths_images_tmp" && \
        must rm "$list_paths_images_tmp" &

    # Save sample to path in env. var. BKFEH_SAMPLE_DIR if set
    save_sample "$list_paths_images";
    
};
export -f yell die must read_stdin read_psarg find_flist;
#==END Define local functions==

main "$@";

# Author: Steven Baltakatei Sandoval
# License: GPLv3+
Commit	Line	Data
9eaab35f	1	#!/usr/bin/env bash
acaa0f3d SBS	2	# Desc: Wrapper for feh that accepts directory paths via posargs or stdin lines.
acaa0f3d SBS	3	# Version: 0.2.0
9eaab35f SBS	4	# Ref/Attrib: [1] Tange, Ole. GNU Parallel with Bash Array. 2019-03-24. https://unix.stackexchange.com/a/508365/411854
	5	# Depends: GNU Parallel, GNU Bash v5.1.16, feh 3.6.3
	6
	7	#===Declare local functions===
	8	yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
	9	die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
	10	must() { "$@" \|\| die "cannot $*"; } # runs args as command, reports args if command fails
	11	checkapp() {
	12	# Desc: If arg is a command, save result in assoc array 'appRollCall'
	13	# Usage: checkapp arg1 arg2 arg3 ...
	14	# Version: 0.1.1
	15	# Input: global assoc. array 'appRollCall'
	16	# Output: adds/updates key(value) to global assoc array 'appRollCall'
	17	# Depends: bash 5.0.3
	18	local returnState
	19
	20	#===Process Args===
	21	for arg in "$@"; do
	22	if command -v "$arg" 1>/dev/null 2>&1; then # Check if arg is a valid command
	23	appRollCall[$arg]="true";
	24	if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
	25	else
	26	appRollCall[$arg]="false"; returnState="false";
	27	fi;
	28	done;
	29
	30	#===Determine function return code===
	31	if [ "$returnState" = "true" ]; then
	32	return 0;
	33	else
	34	return 1;
	35	fi;
	36	} # Check that app exists
	37	checkfile() {
	38	# Desc: If arg is a file path, save result in assoc array 'fileRollCall'
	39	# Usage: checkfile arg1 arg2 arg3 ...
	40	# Version: 0.1.1
	41	# Input: global assoc. array 'fileRollCall'
	42	# Output: adds/updates key(value) to global assoc array 'fileRollCall';
	43	# Output: returns 0 if app found, 1 otherwise
	44	# Depends: bash 5.0.3
	45	local returnState
	46
	47	#===Process Args===
	48	for arg in "$@"; do
	49	if [ -f "$arg" ]; then
	50	fileRollCall["$arg"]="true";
	51	if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
	52	else
	53	fileRollCall["$arg"]="false"; returnState="false";
	54	fi;
	55	done;
	56
	57	#===Determine function return code===
	58	if [ "$returnState" = "true" ]; then
	59	return 0;
	60	else
	61	return 1;
	62	fi;
	63	} # Check that file exists
	64	checkdir() {
	65	# Desc: If arg is a dir path, save result in assoc array 'dirRollCall'
	66	# Usage: checkdir arg1 arg2 arg3 ...
	67	# Version 0.1.1
68	# Input: global assoc. array 'dirRollCall'
69	# Output: adds/updates key(value) to global assoc array 'dirRollCall';
70	# Output: returns 0 if app found, 1 otherwise
71	# Depends: Bash 5.0.3
72	local returnState
73
74	#===Process Args===
75	for arg in "$@"; do
76	if [ -d "$arg" ]; then
77	dirRollCall["$arg"]="true";
78	if ! [ "$returnState" = "false" ]; then returnState="true"; fi
79	else
80	dirRollCall["$arg"]="false"; returnState="false";
81	fi
82	done
83
84	#===Determine function return code===
85	if [ "$returnState" = "true" ]; then
86	return 0;
87	else
88	return 1;
89	fi
90	} # Check that dir exists
91	displayMissing() {
92	# Desc: Displays missing apps, files, and dirs
93	# Usage: displayMissing
94	# Version 0.1.1
95	# Input: associative arrays: appRollCall, fileRollCall, dirRollCall
96	# Output: stderr: messages indicating missing apps, file, or dirs
97	# Depends: bash 5, checkAppFileDir()
98	local missingApps value appMissing missingFiles fileMissing
99	local missingDirs dirMissing
100
101	#==BEGIN Display errors==
102	#===BEGIN Display Missing Apps===
103	missingApps="Missing apps :";
104	#for key in "${!appRollCall[@]}"; do echo "DEBUG:$key => ${appRollCall[$key]}"; done
105	for key in "${!appRollCall[@]}"; do
106	value="${appRollCall[$key]}";
107	if [ "$value" = "false" ]; then
108	#echo "DEBUG:Missing apps: $key => $value";
109	missingApps="$missingApps""$key ";
110	appMissing="true";
111	fi;
112	done;
113	if [ "$appMissing" = "true" ]; then # Only indicate if an app is missing.
114	echo "$missingApps" 1>&2;
115	fi;
116	unset value;
117	#===END Display Missing Apps===
118
119	#===BEGIN Display Missing Files===
120	missingFiles="Missing files:";
121	#for key in "${!fileRollCall[@]}"; do echo "DEBUG:$key => ${fileRollCall[$key]}"; done
122	for key in "${!fileRollCall[@]}"; do
123	value="${fileRollCall[$key]}";
124	if [ "$value" = "false" ]; then
125	#echo "DEBUG:Missing files: $key => $value";
126	missingFiles="$missingFiles""$key ";
127	fileMissing="true";
128	fi;
129	done;
130	if [ "$fileMissing" = "true" ]; then # Only indicate if an app is missing.
131	echo "$missingFiles" 1>&2;
132	fi;
133	unset value;
134	#===END Display Missing Files===
135
136	#===BEGIN Display Missing Directories===
137	missingDirs="Missing dirs:";
138	#for key in "${!dirRollCall[@]}"; do echo "DEBUG:$key => ${dirRollCall[$key]}"; done
139	for key in "${!dirRollCall[@]}"; do
140	value="${dirRollCall[$key]}";
141	if [ "$value" = "false" ]; then
142	#echo "DEBUG:Missing dirs: $key => $value";
143	missingDirs="$missingDirs""$key ";
144	dirMissing="true";
145	fi;
146	done;
147	if [ "$dirMissing" = "true" ]; then # Only indicate if an dir is missing.
148	echo "$missingDirs" 1>&2;
149	fi;
150	unset value;
151	#===END Display Missing Directories===
152
153	#==END Display errors==
154	} # Display missing apps, files, dirs
155	check_depends() {
156	if ! checkapp feh parallel; then displayMissing; die "FATAL:Missing apps."; fi;
157	return 1;
158	}; # check dependencies
acaa0f3d SBS	159	checkInt() {
	160	# Desc: Checks if arg is integer
	161	# Usage: checkInt arg
	162	# Input: arg: integer
	163	# Output: - return code 0 (if arg is integer)
	164	# - return code 1 (if arg is not integer)
	165	# Example: if ! checkInt $arg; then echo "not int"; fi;
	166	# Version: 0.0.1
	167	local returnState
	168
	169	#===Process Arg===
	170	if [[ $# -ne 1 ]]; then
	171	die "ERROR:Invalid number of arguments:$#";
	172	fi;
	173
	174	RETEST1='^[0-9]+$'; # Regular Expression to test
	175	if [[ ! $1 =~ $RETEST1 ]] ; then
	176	returnState="false";
	177	else
	178	returnState="true";
	179	fi;
	180
	181	#===Determine function return code===
	182	if [ "$returnState" = "true" ]; then
	183	return 0;
	184	else
	185	return 1;
	186	fi;
	187	} # Checks if arg is integer
335b71e1 SBS	188	read_stdin() {
335b71e1 SBS	189	# Desc: Consumes stdin; outputs as stdout lines
9eaab35f	190	# Input: stdin (consumes)
9eaab35f	191	# Output: stdout (newline delimited)
335b71e1	192	# Example: printf "foo\nbar\n" \| read_stdin
9eaab35f	193	# Depends: GNU bash (version 5.1.16)
335b71e1 SBS	194	# Version: 0.0.1
335b71e1 SBS	195	local input_stdin output;
9eaab35f SBS	196
	197	# Store stdin
	198	if [[ -p /dev/stdin ]]; then
	199	input_stdin="$(cat -)";
335b71e1	200	fi;
966a8d11	201
335b71e1	202	# Store as output array elements
9eaab35f SBS	203	## Read in stdin
	204	if [[ -n $input_stdin ]]; then
	205	while read -r line; do
	206	output+=("$line");
	207	done < <(printf "%s\n" "$input_stdin");
	208	fi;
335b71e1 SBS	209
	210	# Print to stdout
	211	printf "%s\n" "${output[@]}";
	212	}; # read stdin to stdout lines
	213	read_psarg() {
	214	# Desc: Reads arguments; outputs as stdout lines
	215	# Input: args
	216	# Output: stdout (newline delimited)
	217	# Example: read_psarg "$@"
	218	# Depends: GNU bash (version 5.1.16)
	219	# Version: 0.0.1
	220	local input_psarg output;
	221
	222	# Store arguments
	223	if [[ $# -gt 0 ]]; then
	224	input_psarg="$*";
	225	fi;
	226
	227	# Store as output array elements
9eaab35f SBS	228	## Read in positional arguments
	229	if [[ -n $input_psarg ]]; then
	230	for arg in "$@"; do
	231	output+=("$arg");
	232	done;
	233	fi;
	234
	235	# Print to stdout
	236	printf "%s\n" "${output[@]}";
335b71e1 SBS	237	}; # read positional argument to stdout lines
335b71e1 SBS	238	find_flist() {
9eaab35f SBS	239	# Desc: print file list to stdout via `find` using script parameters
	240	# Input: arg1: path to dir
	241	# var: find_depth
	242	# var: pattern_find_iregex
	243	# var: find_size
	244	if [[ ! -d "$1" ]]; then return 1; fi;
335b71e1	245	must find "$1" -maxdepth "$fdepth" -type f -iregex "$firegex" -size +"$fsize";
9eaab35f	246	}; # print file list to stdout from dir with script parameters
4db78240 SBS	247	save_sample() {
	248	# Usage: save_sample arg1
	249	# Input: arg1 list_paths (list of files to take samples from)
	250	# envvar BKFEH_SAMPLE_DIR (environment variable set outside of this script)
acaa0f3d	251	# envvar BKFEH_SAMPLE_SIZE (space limit for sample dir files)
4db78240 SBS	252	# Depends: yell(), GNU Parallel, GNU find, GNU Coreutils 8.32 (cut, find, du)
4db78240 SBS	253	local list_paths
acaa0f3d SBS	254	sample_count="100"; # max number of images to put in sample dir
	255	sample_max_space="10000000"; # max bytes to put in sample dir
	256
	257	# Load environment variables if set
4db78240	258	if [[ ! -v BKFEH_SAMPLE_DIR ]]; then return 0; fi; # return early if environment var not set.
acaa0f3d SBS	259	if [[ -v BKFEH_SAMPLE_SIZE ]] && checkInt "$BKFEH_SAMPLE_SIZE"; then
	260	sample_max_space="$BKFEH_SAMPLE_SIZE";
	261	fi;
	262	if [[ -v BKFEH_SAMPLE_COUNT ]] && checkInt "$BKFEH_SAMPLE_COUNT"; then
	263	sample_count="$BKFEH_SAMPLE_COUNT";
	264	fi;
4db78240 SBS	265
	266	if [[ ! -z "$1" ]]; then
	267	list_paths="$1"; # newline-delimited list of file paths to sample from
	268	else
	269	yell "ERROR:NO paths available to sample.";
	270	fi;
	271
	272	if [[ -d "$BKFEH_SAMPLE_DIR" ]]; then
	273	sample_dir="$BKFEH_SAMPLE_DIR";
	274	yell "STATUS:Environment variable BKFEH_SAMPLE_DIR set. Clearing and saving samples...";
	275
	276	## clear previous sample
	277	count_samples="$(find $BKFEH_SAMPLE_DIR -maxdepth 1 -type f \| wc -l)";
	278	find "$BKFEH_SAMPLE_DIR" -maxdepth 1 -type f -exec rm '{}' \; ;
	279
	280	## save random sample
	281	yell "STATUS:Saving random sample of size $sample_count to $BKFEH_SAMPLE_DIR...";
	282	list_paths_sample="$(echo "$list_paths" \| shuf \| head -n"$sample_count")";
	283	while read -r line; do
	284	if [[ -z "$line" ]]; then continue; fi;
	285	### check size limit
	286	sample_act_space="$(du -bd1 "$BKFEH_SAMPLE_DIR" \| cut -f1 )"; # actual used space
	287	cand_space="$(du -bd1 "$line" \| cut -f1 )"; # size of candidate file to add
	288	sample_req_space="$((sample_act_space + cand_space))";
	289	if [[ "$sample_req_space" -lt "$sample_max_space" ]]; then
	290	#### add file to sample dir
	291	cp -n "$line" "$BKFEH_SAMPLE_DIR" ;
	292	fi;
	293	done < <( echo "$list_paths_sample" );
	294	else
	295	yell "ERROR:Does not exist: $BKFEH_SAMPLE_DIR";
	296	fi;
	297	}; # save sample of files
	298
9eaab35f SBS	299	main() {
9eaab35f SBS	300	# Depends: read_stdin_psarg() v0.0.1, check_depends()
966a8d11	301	local re_dotfile;
335b71e1	302	declare -a dirs_stdin dirs_psarg;
9eaab35f SBS	303	declare -a paths_images;
	304	declare list_paths_images;
	305	check_depends;
	306
335b71e1 SBS	307	#Populate dirs_stdin and dirs_psarg arrays
335b71e1 SBS	308	## Read stdin as lines
966a8d11	309	re_dotfile="^\."; # first char is a dot
9eaab35f	310	while read -r line; do
4db78240	311	line="$(readlink -e "$line")";
966a8d11	312	# Check if dir
9eaab35f SBS	313	if [[ ! -d "$line" ]]; then
	314	echo "ERROR:Not a dir:$line" 1>&2;
	315	continue;
	316	fi;
966a8d11 SBS	317	dir_name="$(basename "$line")";
	318	# Exclude dotdirs
	319	if [[ "$dir_name" =~ $re_dotfile ]]; then
	320	echo "ERROR:Is a dotdir:$line" 1>&2;
	321	continue
	322	fi;
335b71e1 SBS	323	dirs_stdin+=("$line");
	324	done < <(read_stdin);
	325	## Read positional arguments as lines
	326	re_dotfile="^\."; # first char is a dot
	327	while read -r line; do
4db78240	328	line="$(readlink -e "$line")";
335b71e1 SBS	329	# Check if dir
	330	if [[ ! -d "$line" ]]; then
	331	echo "ERROR:Not a dir:$line" 1>&2;
	332	continue;
	333	fi;
	334	dir_name="$(basename "$line")";
	335	# Exclude dotdirs
	336	if [[ "$dir_name" =~ $re_dotfile ]]; then
	337	echo "ERROR:Is a dotdir:$line" 1>&2;
	338	continue
	339	fi;
	340	dirs_psarg+=("$line");
	341	done < <(read_psarg "$@");
	342
	343	# Catch all arrays empty
	344	if [[ "${#dirs_stdin[@]}" -le 0 ]] && [[ "${#dirs_psarg[@]}" -le 0 ]]; then
	345	die "FATAL:No valid directories provided.";
	346	fi;
9eaab35f SBS	347
9eaab35f SBS	348	# Generate file list
335b71e1 SBS	349	# Find settings
	350	firegex=".+\(jpg\\|jpeg\\|gif\\|png\\|webm\)$"; # update according to `find . -type f \| grep -Eo "\.([[:alnum:]])+$" \| sort -u`
	351	fsize="10k"; # default: minimum "10k"
	352	export firegex fsize ; # export for parallel
	353	## Call find_filelist() in parallel for positional argument input
	354	if [[ "${#dirs_psarg[@]}" -gt 0 ]]; then
	355	fdepth=10; export fdepth; # 10 for dirs from positional arguments
	356	paths_images+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_psarg[@]}" )"); # See [1]
	357	fi;
	358	## Call find_filelist() in parallel for stdin input
	359	if [[ "${#dirs_stdin[@]}" -gt 0 ]]; then
	360	fdepth=1; export fdepth; # 1 ofr dirs from stdin
	361	paths_images+=("$( parallel find_flist {} "$fdepth" "$firegex" "$fsize" ::: "${dirs_stdin[@]}" )"); # See [1]
	362	fi;
	363
9eaab35f SBS	364	# Convert paths_images array into file list
	365	for i in "${!paths_images[@]}"; do
	366	list_paths_images="$(printf "%s\n%s" "${paths_images[$i]}" "$list_paths_images")";
	367
	368	# Get stats
	369	file_count="$(wc -l < <(echo -n "$list_paths_images"))";
	370	echo "$DEBUG:file_count:$file_count"
	371	done;
966a8d11 SBS	372
966a8d11 SBS	373	# Sort, remove duplicate paths
9eaab35f SBS	374	list_paths_images="$(echo "$list_paths_images" \| sort -u \| tr -s '\n')";
9eaab35f SBS	375
335b71e1 SBS	376	# Remove paths with dotfiles
	377	list_paths_images="$(echo "$list_paths_images" \| grep -viE "/\." )";
	378
9eaab35f SBS	379	# Write
	380	list_paths_images_tmp="/dev/shm/$(date +%Y%m%dT%H%M%S.%N%z)"..feh_paths.txt;
	381	must echo -n "$list_paths_images" > "$list_paths_images_tmp";
	382
	383	# Print stats
	384	yell "STATUS:Built file list in $SECONDS seconds.";
	385
	386	# Run feh with filelist
acaa0f3d SBS	387	feh --full-screen --auto-zoom --draw-filename --filelist "$list_paths_images_tmp" && \
acaa0f3d SBS	388	must rm "$list_paths_images_tmp" &
9eaab35f	389
acaa0f3d SBS	390	# Save sample to path in env. var. BKFEH_SAMPLE_DIR if set
	391	save_sample "$list_paths_images";
	392
9eaab35f	393	};
335b71e1	394	export -f yell die must read_stdin read_psarg find_flist;
9eaab35f SBS	395	#==END Define local functions==
	396
	397	main "$@";
	398
	399	# Author: Steven Baltakatei Sandoval
	400	# License: GPLv3+