package domain

import (
	"errors"
	"fmt"

	"github.com/gosimple/slug"
)

type ErrorCode uint8

const (
	ErrorCodeUnknown ErrorCode = iota
	ErrorCodeEntityNotFound
	ErrorCodeIncorrectInput
)

func (e ErrorCode) String() string {
	switch e {
	case ErrorCodeEntityNotFound:
		return "entity-not-found"
	case ErrorCodeIncorrectInput:
		return "incorrect-input"
	case ErrorCodeUnknown:
		fallthrough
	default:
		return "unknown-error"
	}
}

type Error interface {
	error
	Code() ErrorCode
	Slug() string
}

type ErrorWithParams interface {
	Error
	Params() map[string]any
}

type ValidationError struct {
	Field string
	Err   error
}

var _ ErrorWithParams = ValidationError{}

func (e ValidationError) Error() string {
	return fmt.Sprintf("%s: %s", e.Field, e.Err)
}

func (e ValidationError) Code() ErrorCode {
	var domainErr Error
	if errors.As(e.Err, &domainErr) {
		return domainErr.Code()
	}
	return ErrorCodeIncorrectInput
}

func (e ValidationError) Slug() string {
	s := "validation"
	var domainErr Error
	if errors.As(e.Err, &domainErr) {
		s = domainErr.Slug()
	}
	return fmt.Sprintf("%s-%s", slug.Make(e.Field), s)
}

func (e ValidationError) Params() map[string]any {
	var withParams ErrorWithParams
	ok := errors.As(e.Err, &withParams)
	if !ok {
		return nil
	}
	return withParams.Params()
}