package exerr

import (
	"encoding/json"
	"errors"
	"fmt"
	"go.mongodb.org/mongo-driver/v2/bson"
)

type ErrorCategory struct{ Category string }

var (
	CatWrap    = ErrorCategory{"Wrap"}    // The error is simply wrapping another error (e.g. when a grpc call returns an error)
	CatSystem  = ErrorCategory{"System"}  // An internal system error (e.g. connection to db failed)
	CatUser    = ErrorCategory{"User"}    // The user (the API caller) did something wrong (e.g. he has no permissions to do this)
	CatForeign = ErrorCategory{"Foreign"} // A foreign error that some component threw (e.g. an unknown mongodb error), happens if we call Wrap(..) on an non-bmerror value
)

func (e *ErrorCategory) UnmarshalJSON(bytes []byte) error {
	return json.Unmarshal(bytes, &e.Category)
}

func (e ErrorCategory) MarshalJSON() ([]byte, error) {
	return json.Marshal(e.Category)
}

func (e *ErrorCategory) UnmarshalBSONValue(bt byte, data []byte) error {
	if bson.Type(bt) == bson.TypeNull {
		// we can't set nil in UnmarshalBSONValue (so we use default(struct))
		// Use mongoext.CreateGoExtBsonRegistry if you need to unmarsh pointer values
		// https://stackoverflow.com/questions/75167597
		// https://jira.mongodb.org/browse/GODRIVER-2252
		*e = ErrorCategory{}
		return nil
	}
	if bson.Type(bt) != bson.TypeString {
		return errors.New(fmt.Sprintf("cannot unmarshal %v into String", bson.Type(bt)))
	}
	var tt string
	err := bson.RawValue{Type: bson.Type(bt), Value: data}.Unmarshal(&tt)
	if err != nil {
		return err
	}
	*e = ErrorCategory{tt}
	return nil
}

func (e ErrorCategory) MarshalBSONValue() (byte, []byte, error) {
	tp, data, err := bson.MarshalValue(e.Category)
	return byte(tp), data, err
}

//goland:noinspection GoUnusedGlobalVariable
var AllCategories = []ErrorCategory{CatWrap, CatSystem, CatUser, CatForeign}