#!/bin/sh

die () {
        echo "$@" >&2
        exit 1
}

command_list () {
        grep -v '^#' "$1"
}

get_categories () {
        tr ' ' '\n'|
        grep -v '^$' |
        sort |
        uniq
}

category_list () {
        command_list "$1" |
        cut -c 40- |
        get_categories
}

get_synopsis () {
        sed -n '
                /^NAME/,/'"$1"'/H
                ${
                        x
                        s/.*'"$1"' - \(.*\)/N_("\1")/
                        p
                }' "Documentation/$1.txt"
}

define_categories () {
        echo
        echo "/* Command categories */"
        bit=0
        category_list "$1" |
        while read cat
        do
                echo "#define CAT_$cat (1UL << $bit)"
                bit=$(($bit+1))
        done
        test "$bit" -gt 32 && die "Urgh.. too many categories?"
}

print_command_list () {
        echo "static struct cmdname_help command_list[] = {"

        command_list "$1" |
        while read cmd rest
        do
                printf "        { \"$cmd\", $(get_synopsis $cmd), 0"
                for cat in $(echo "$rest" | get_categories)
                do
                        printf " | CAT_$cat"
                done
                echo " },"
        done
        echo "};"
}

echo "/* Automatically generated by generate-cmdlist.sh */
struct cmdname_help {
        const char *name;
        const char *help;
        uint32_t category;
};
"
if test -z "$2"
then
        define_categories "$1"
        echo
        print_command_list "$1"
        exit 0
fi

echo "static const char *common_cmd_groups[] = {"

grps=grps$$.tmp
match=match$$.tmp
trap "rm -f '$grps' '$match'" 0 1 2 3 15

sed -n '
        1,/^### common groups/b
        /^### command list/q
        /^#/b
        /^[     ]*$/b
        h;s/^[^         ][^     ]*[     ][      ]*\(.*\)/       N_("\1"),/p
        g;s/^\([^       ][^     ]*\)[   ].*/\1/w '$grps'
        ' "$1"
printf '};\n\n'

n=0
substnum=
while read grp
do
        echo "^git-..*[         ]$grp"
        substnum="$substnum${substnum:+;}s/[    ]$grp/$n/"
        n=$(($n+1))
done <"$grps" >"$match"

printf 'static struct cmdname_help common_cmds[] = {\n'
grep -f "$match" "$1" |
sed 's/^git-//' |
sort |
while read cmd tags
do
        tag=$(echo "$tags" | sed "$substnum; s/[^0-9]//g")
        echo "  {\"$cmd\", $(get_synopsis git-$cmd), $tag},"
done
echo "};"