# Sourced, not run: organization selector options, the shell half of
# packages/organization/src/selector.mjs (rename design r2, "Selector scopes and parser matrix"). A
# script in the same checkout sources it; it defines functions only and runs no other program.
#
# --org and --business are one option family (id), and --org-file and --business-file are another
# (file). A scope is one parser's own options, so the caller's own loop decides which tokens are
# selectors; text after a separator or a value another option consumes is never passed here. In a
# scope each spelling may appear once, and a second spelling must carry exactly the same value.
#
#   selector_take SCOPE FAMILY REFUSE VALID FLAG [VALUE]
#     SCOPE   [a-z0-9_]+, the scope's name; each keeps its own spellings and value
#     FAMILY  id or file
#     REFUSE  a function called as REFUSE KIND MESSAGE that must exit; KIND is missing, flag,
#             repeated, invalid or differ, so each script keeps its exit codes and wording
#     VALID   a predicate called as VALID VALUE, or - when the caller checks the value itself
#     FLAG    the spelling given
#     VALUE   absent when the argument list ended there; pass "${@:2:1}" from a loop on "$@"
#   selector_value SCOPE   prints the scope's value, nothing when none was given
#
# A missing or empty value, one starting with "-", one VALID refuses, a repeated spelling and two
# spellings with different values all refuse. File values are compared as given, not as paths.

selector__bug() { echo "selector.sh: $*" >&2; exit 70; }

selector_take() {
    [ $# -ge 5 ] && [ $# -le 6 ] || selector__bug "selector_take takes 5 or 6 arguments, not $#"
    local scope="$1" family="$2" refuse="$3" valid="$4" flag="$5"
    [[ "$scope" =~ ^[a-z0-9_]+$ ]] || selector__bug "bad scope name $scope"
    case "$family:$flag" in
        id:--business|id:--org|file:--business-file|file:--org-file) ;;
        *) selector__bug "$flag is not a $family selector" ;;
    esac
    local seen_name="SELECTOR_SEEN_$scope" value_name="SELECTOR_VALUE_$scope"
    local seen="${!seen_name-}" current="${!value_name-}" first
    case " $seen " in *" $flag "*) "$refuse" repeated "$flag given twice"; selector__bug "$refuse returned" ;; esac
    if [ $# -lt 6 ] || [ -z "$6" ]; then "$refuse" missing "$flag needs one value"; selector__bug "$refuse returned"; fi
    local value="$6"
    case "$value" in -*) "$refuse" flag "$flag needs one value, not $value"; selector__bug "$refuse returned" ;; esac
    if [ "$valid" != - ] && ! "$valid" "$value"; then "$refuse" invalid "$flag $value is not valid"; selector__bug "$refuse returned"; fi
    first="${seen%% *}"
    if [ -n "$seen" ] && [ "$current" != "$value" ]; then
        "$refuse" differ "$first $current and $flag $value conflict"; selector__bug "$refuse returned"
    fi
    printf -v "$seen_name" '%s' "${seen:+$seen }$flag"
    printf -v "$value_name" '%s' "$value"
}

selector_value() {
    [[ "${1-}" =~ ^[a-z0-9_]+$ ]] || selector__bug "bad scope name ${1-}"
    local value_name="SELECTOR_VALUE_$1"
    printf '%s' "${!value_name-}"
}