package presenter

import (
	"context"
	"errors"
	"fmt"
	"log/slog"

	"github.com/99designs/gqlgen/graphql"
	"github.com/vektah/gqlparser/v2/gqlerror"
)

func New[C ~string, E ~string](logger *slog.Logger, codes []C, entities []E, internalErrorCode C) func(ctx context.Context, e error) *gqlerror.Error {
	return func(ctx context.Context, e error) *gqlerror.Error {
		err := graphql.DefaultErrorPresenter(ctx, e)
		var codedError CodedError
		if errors.As(e, &codedError) {
			code := toModelErrorCode(codedError.Code, codes, internalErrorCode)
			errorEntity := toModelErrorEntity(codedError.Entity, entities)
			extensions := map[string]interface{}{"code": code}
			if len(errorEntity) > 0 {
				extensions["errorEntity"] = errorEntity
			}
			if len(codedError.Params) > 0 {
				extensions["params"] = codedError.Params
			}
			err.Extensions = extensions
		} else {
			err.Extensions = map[string]interface{}{"code": internalErrorCode}
		}
		if logError(e) {
			logger.ErrorContext(ctx, fmt.Sprintf("%v", e))
		}
		return err
	}
}

func logError(err error) bool {
	return !errors.Is(err, context.Canceled)
}

func toModelErrorCode[C ~string](code Code, codes []C, internalErrorCode C) C {
	for _, c := range codes {
		if string(c) == string(code) {
			return c
		}
	}
	return internalErrorCode
}

func toModelErrorEntity[E ~string](entity Entity, entities []E) E {
	for _, e := range entities {
		if string(e) == string(entity) {
			return e
		}
	}
	return ""
}