package domain

import "strings"

func validResourceID(id string) bool {
	if !strings.Contains(id, "/") {
		return strings.TrimSpace(id) != ""
	}
	if strings.Count(id, "/") != 1 {
		return false
	}
	namespace, localID, _ := strings.Cut(id, "/")
	return namespace != "" && localID != ""
}

func validResourceNamespace(namespace string) bool {
	return strings.TrimSpace(namespace) != "" && !strings.Contains(namespace, "/")
}

func validLocalResourceKey(key string) bool {
	return strings.TrimSpace(key) != "" && !strings.Contains(key, "/")
}

func qualifyResourceID(id, namespace string) (string, bool) {
	if !validResourceID(id) || (namespace != "" && !validResourceNamespace(namespace)) {
		return "", false
	}
	if strings.Contains(id, "/") || namespace == "" {
		return id, true
	}
	return namespace + "/" + id, true
}

func resourceNamespaceFromID(id string) (string, bool) {
	if !validResourceID(id) || !strings.Contains(id, "/") {
		return "", false
	}
	namespace, _, _ := strings.Cut(id, "/")
	return namespace, true
}

// IsValidResourceID reports whether id is an unqualified resource ID or one
// valid namespace/local-ID pair.
func IsValidResourceID(id string) bool { return validResourceID(id) }

// QualifyResourceID validates id and applies namespace to an unqualified ID.
// An already-qualified ID is returned unchanged.
func QualifyResourceID(id, namespace string) (string, bool) {
	return qualifyResourceID(id, namespace)
}

// IsValidResourceNamespace reports whether namespace is nonblank and contains
// no namespace separator.
func IsValidResourceNamespace(namespace string) bool { return validResourceNamespace(namespace) }

// IsValidLocalResourceKey reports whether key is a nonblank key for a
// namespace-local resource mapping.
func IsValidLocalResourceKey(key string) bool { return validLocalResourceKey(key) }

// QualifyLocalResourceID combines a validated namespace and local mapping key.
// An empty namespace leaves a valid unqualified key unchanged.
func QualifyLocalResourceID(namespace, key string) (string, bool) {
	if !validLocalResourceKey(key) || (namespace != "" && !validResourceNamespace(namespace)) {
		return "", false
	}
	if namespace == "" {
		return key, true
	}
	return namespace + "/" + key, true
}