#!/bin/bash

FFOO_DIR=${FFOO_DIR:-__FFOO_DIR__}
FFOO_DEBUG=${FFOO_DEBUG:-false}
FFOO_DEBUGINIT=${FFOO_DEBUGINIT:-false}
FFOO_INCLUDE=${FFOO_INCLUDE:-$FFOO_DIR/include}
FFOO_MKPRETTY=${FFOO_MKPRETTY:-plain}
FFOO_VERBOSE=${FFOO_VERBOSE:-false}
FFOO_VERSION=__VERSION__

ffoo() {
    case $1 in
        __debug)
            $FFOO_DEBUGINIT || return 0
            shift
            echo "debug: $@" >&2
            ;;
        __die)
            shift
            echo "$@" >&2
            test -z "$PS1" && exit 1
            ;;

        doc)
            ffoo _cat_function "$2" | ffoo _filter_doc
            ;;
        import)
            ffoo __debug "importing module $2"
            local mfile=$(ffoo _select_mfile $2)
            test -n "$mfile" || ffoo __die "cannot find module: $2"
            ffoo __debug "found module file: $mfile"
            bash -n $mfile && . $mfile
            return $?
            ;;

        _parse)
            # convert stdin from $1 to $2 (can be 1:N conversion)
            local src=$2
            local tgt=$3
            local line
            while read line;
            do
                ffoo _parse_${src}_to_${tgt} "$line"
            done
            ;;
        _parse_path_to_mod)
            local fname="${2##*/}"; echo "${fname%%.sh}"
            ;;
        _parse_fspec_to_mod)
            echo "${2%%.*}"
            ;;
        _parse_fspec_to_fun)
            local mod=$(ffoo _parse_fspec_to_mod "$2")
            echo "${2##$mod.}"
            ;;
        _parse_path_to_fspeclist)
            grep -HE '^[[:alnum:]_]+\(\) \{' "$2" \
              | sed -e 's/^.*\///; s/\.sh:/./; s/(.*//'
            ;;
        _parse_path_to_fnlist)
            grep -E '^[[:alnum:]_]+\(\) \{' "$2" \
              | sed -e 's/^.*\///; s/(.*//'
            ;;

        _cat_function)
            local mod=$(ffoo _parse_fspec_to_mod "$2")
            local fun=$(ffoo _parse_fspec_to_fun "$2")
            local mfname=$(ffoo _select_mfile "$mod")
            test -n "$mfname" || ffoo __die "unknown module: $mod"
            name=$fun perl -we '
                undef $/;
                my $name = $ENV{name};
                my ($fbody) = <> =~ m/^($name\(\) \{.*?^\}$)/ms;
                print "$fbody\n" if defined $fbody;
            ' < "$mfname"
            ;;
        _filter_doc)
            # 1. line "^    #$" opens doc
            # 2. first line that is not "^    #" closes doc
            # 3. first and last line will be stripped
            perl -we '
                my $isdoc;
                while (<>) {
                    if (m/^    #$/) {
                        $isdoc = 1;
                    } elsif (m/^    [^#]/) {
                        exit;
                    }
                    next unless $isdoc;
                    s/    # ?//;
                    print;
                }' \
              | head -n -1 \
              | tail -n +2
            ;;

        _list_modules)
            ffoo _list_mfiles "$2" | ffoo _parse path mod
            ;;
        _list_mfiles)
            local ex="${2:-*}"
            find $FFOO_INCLUDE ${FFOO_PATH/:/ } -name "$ex.sh"
            ;;
        _select_mfile)
            ffoo _list_mfiles $2 | head -1
            ;;
        _list_functions)
            ffoo _list_mfiles "$2" | ffoo _parse path fspeclist
            ;;
        _list_functions_in)
            ffoo _list_mfiles "$2" | ffoo _parse path fnlist
            ;;

        *)
            ffoo __die "unknown ffoo command: $1"
            ;;
    esac
}

ffoo __debug "FFOO_DIR='$FFOO_DIR'"
ffoo __debug "FFOO_DEBUG='$FFOO_DEBUG'"
ffoo __debug "FFOO_DEBUGINIT='$FFOO_DEBUGINIT'"
ffoo __debug "FFOO_INCLUDE='$FFOO_INCLUDE'"
ffoo __debug "FFOO_INI_PATH='$FFOO_INI_PATH'"
ffoo __debug "FFOO_MKPRETTY='$FFOO_MKPRETTY'"
ffoo __debug "FFOO_VERBOSE='$FFOO_VERBOSE'"
ffoo __debug "FFOO_VERSION='$FFOO_VERSION'"