package registry

import (
	"fmt"
	"reflect"

	cda "git.loafle.net/commons_go/di/annotation"
	cdur "git.loafle.net/commons_go/di/util/reflect"
)

type ComponentRegistry interface {
	RegisterType(t reflect.Type, ca *cda.ComponentAnnotation) error
	RegisterFactory(i interface{}, ca *cda.ComponentAnnotation) error

	GetInstance(t reflect.Type) (interface{}, error)
	GetInstanceByName(name string) (interface{}, error)
}

type defaultComponentRegistry struct {
	definitionsByType map[reflect.Type]*ComponentDefinition

	definitionByName map[string]*ComponentDefinition
}

func (cr *defaultComponentRegistry) RegisterType(t reflect.Type, ca *cda.ComponentAnnotation) error {
	if nil == t {
		return fmt.Errorf("DI: t[reflect.Type] is nil")
	}
	if !cdur.IsTypeKind(t, reflect.Struct, true) {
		return fmt.Errorf("DI: t[reflect.Type] must be specified but is %v", t)
	}

	rt, pkgName, tName := cdur.GetTypeName(t)
	cr.definitions[name] = rt

	return nil
}

func (cr *defaultComponentRegistry) GetInstance(t reflect.Type) (interface{}, error) {
	if nil == t {
		return nil, fmt.Errorf("DI: t[reflect.Type] is nil")
	}

	cd, ok := cr.definitionsByType[t]
	if !ok {
		cd = cr.buildDefinition(t)
	}

	return nil, nil
}

func (cr *defaultComponentRegistry) GetInstanceByName(name string) (interface{}, error) {

	return nil, nil
}

func (cr *defaultComponentRegistry) buildDefinition(t reflect.Type) (*ComponentDefinition, error) {
	if nil == t {
		return nil, fmt.Errorf("DI: t[reflect.Type] is nil")
	}

	rt, pkgName, tName := cdur.GetTypeName(t)
	cd := &ComponentDefinition{}
	cd.PkgName = pkgName
	cd.TypeName = tName
	cd.Type = t
	cd.RealType = rt

	return nil, nil
}