metadata.sh

#!/bin/bash
is_debug=1
is_warning=1

dst_file=readme.txt
tmp_file=tmp_readme.txt

# used for bash4 hashmaps
if [[ "${BASH_VERSION::1}" -lt "4" ]] || [[ "${BASH_VERSION::1}" == "" ]]
then
    echo "Error: this script requires bash 4 or later"
    echo "       you have $BASH_VERSION"
    exit 1
fi

if ! [ -x "$(command -v sha1sum)" ];
then
    echo 'Error: sha1sum is not installed.' >&2
    exit 1
fi

function dbg() {
    if [ "$is_debug" -eq 0 ]
    then
        return
    fi
    echo "[*] $1"
}
function wrn() {
    if [ "$is_warning" -eq 0 ]
    then
        return
    fi
    echo "[!] $1"
}

function delete_cache() {
    if [ -f "$tmp_file" ]
    then
        rm "$tmp_file"
    fi
}

function usage() {
    echo "usage: $(basename "$0") <directory> [OPTION]"
    echo "options:"
    echo " -Werror	handle warnings as errors"
    echo "example: $(basename "$0") cartoon -Werror"
}

if [ "$#" -lt "1" ]
then
	usage
	exit 0
fi

dir="$1"
is_werror=0
warnings=0

for arg in "$@"
do
	if [ "${arg::1}" == "-" ]
	then
		if [ "$arg" == "--help" ] || [ "$arg" == "-h" ]
		then
			usage
			exit 0
		elif [ "$arg" == "-Werror" ]
		then
			is_werror=1
		else
			echo "Error: invalid option '$arg'"
		fi
	elif [ "$dir" == "" ]
	then
		dir="$arg"
	fi
done

dbg "Parsing dir '$dir' ..."
if [ ! -d "$dir" ]
then
    echo "Error: invalid directory '$dir'"
    exit 1
fi

cd "$dir" || exit 1

if [ ! -f "$dst_file" ]
then
    echo "Error: file not found '$dst_file'"
    exit 1
fi

delete_cache

declare -A file_images

function check_line() {
    local type="$1"
    local value="$2"
    local expected="$3"
    local line_num="$4"
    if [ "${value:0:1}" != "$expected" ]
    then
        echo "Error: got token '${value:0:1}' expected '$expected'."
        echo "expected type: $type"
        echo "$line_num: $value"
        delete_cache
        exit 1
    fi
}

function add_image() {
    local path="$1"
    local author="$2"
    local notes="$3"
    local tags="$4"
    local old_sha1="$5"
    local line_num="$6"
    check_line "path" "$path" "-" "$line_num"
    check_line "author" "$author" " " "$line_num"
    check_line "notes" "$notes" " " "$line_num"
    check_line "tags" "$tags" " " "$line_num"
    check_line "sha1" "$old_sha1" " " "$line_num"
    old_sha1="$(echo "${old_sha1#*:}" | xargs)"
    path="${path:2}"
    author="$(echo "${author#*:}" | xargs)"
    notes="$(echo "${notes#*:}" | xargs)"
    tags="$(echo "${tags#*:}" | xargs)"
    if [ "$author" != "" ]; then author=" $author"; fi
    if [ "$notes" != "" ]; then notes=" $notes"; fi
    if [ "$tags" != "" ]; then tags=" $tags"; fi
    new_sha1="$(sha1sum "$path" | cut -d ' ' -f1)"
    if [ "$old_sha1" != "$new_sha1" ]
    then
        wrn "WARNING sha1 missmatch '$path'"
        wrn "'$old_sha1' -> '$new_sha1'"
    	warnings="$((warnings + 1))"
    fi
    dbg "Adding image '$path' ..."
    dbg " author = '$author'"
    dbg " notes  = '$notes'"
    dbg " tags   = '$tags'"
    dbg " sha1   = '$old_sha1'"
    read -rd '' credit << EOF
- $path
    author:$author
    notes:$notes
    tags:$tags
    sha1: $new_sha1
EOF
    file_images["$path"]="$credit"
}

i=0
line_num=0
file_path=INVALID
sha1=INVALID
author=INVALID
notes=INVALID
tags=INVALID
while IFS= read -r l
do
    i=$((i+1))
    line_num=$((line_num+1))
    if [ "$i" -eq 1 ]; then
        file_path="$l"
    elif [ "$i" -eq 2 ]; then
        author="$l"
    elif [ "$i" -eq 3 ]; then
        notes="$l"
    elif [ "$i" -eq 4 ]; then
        tags="$l"
    elif [ "$i" -eq 5 ]; then
        sha1="$l"
        i=0
        found=0
        while IFS= read -r -d '' f
        do
            img="- ${f:2}"
            if [ "$img" == "$file_path" ]
            then
                found=1
                break;
            fi
        done < <(find . -type f \( \
            -name "*.jpg" -o \
            -name "*.svg" -o \
            -name "*.xcf" -o \
            -name "*.rules" -o \
            -name "*.json" -o \
            -name "*.png" \) -print0)
        if [ "$found" -eq 0 ]
        then
            wrn "WARNING delete image only exisiting in readme:"
            wrn "$file_path"
	    warnings="$((warnings + 1))"
        else
            add_image "$file_path" "$author" "$notes" "$tags" "$sha1" "$line_num"
        fi
    fi
done < readme.txt

if [ "$i" -ne 0 ]
then
    echo "Error: invalid index $i != 0"
    delete_cache
    exit 1
fi

if [ "$warnings" -gt "0" ] && [ "$is_werror" == "1" ]
then
	echo "Error: finished with $warnings warnings and -Werror is active"
	exit 1
fi

# find order change change
# https://serverfault.com/questions/181787/find-command-default-sorting-order/181815#181815
# thus sort to ensure same order on different machines
# use -z to sort -print0
find . -type f \( \
    -name "*.jpg" -o \
    -name "*.svg" -o \
    -name "*.xcf" -o \
    -name "*.rules" -o \
    -name "*.json" -o \
    -name "*.png" \) -print0 | sort -z | while IFS= read -r -d '' f
do
    img=${f:2}
    if [[ -n "${file_images[$img]:-}" ]]
    then
        dbg "'$img' is in list"
        echo "${file_images[$img]}" >> "$tmp_file"
        # file_images["$img"]="XXX" # empty element
    else
        dbg "'$img' is in not list"
        {
            echo "- $img"
            echo "    author:"
            echo "    notes:"
            echo "    tags:"
            echo "    sha1: $(sha1sum "$img" | cut -d ' ' -f1)"
        } >> "$tmp_file"
    fi
done

mv "$tmp_file" "$dst_file"
delete_cache