package apierr

import (
	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/api"
)

func Wrap(err error) error {
	apiErr := &api.Error{}
	if !errors.As(err, &apiErr) {
		return err
	}

	switch apiErr.Code {
	case api.ErrCodeInvalidFieldValue:
		return wrapInvalidFieldValueErr(apiErr)

	default:
		return wrapApiErrorWithMessage(apiErr)
	}
}

func wrapApiErrorWithMessage(err *api.Error) error {
	data, ok := err.Data.(map[string]any)
	if !ok {
		return err
	}

	rawMessage, exists := data["message"]
	if !exists {
		return err
	}

	message, ok := rawMessage.(string)
	if !ok {
		return err
	}

	return errors.Wrapf(err, message)
}

func wrapInvalidFieldValueErr(err *api.Error) error {
	data, ok := err.Data.(map[string]any)
	if !ok {
		return err
	}

	rawFields, exists := data["Fields"]
	if !exists {
		return err
	}

	fields, ok := rawFields.([]any)
	if !ok {
		return err
	}

	var (
		field string
		rule  string
	)

	if len(fields) == 0 {
		return err
	}

	firstField, ok := fields[0].(map[string]any)
	if !ok {
		return err
	}

	param, ok := firstField["Param"].(string)
	if !ok {
		return err
	}

	tag, ok := firstField["Tag"].(string)
	if !ok {
		return err
	}

	fieldName, ok := firstField["Field"].(string)
	if !ok {
		return err
	}

	field = fieldName
	rule = tag + "=" + param

	return errors.Wrapf(err, "server expected field '%s' to match rule '%s'", field, rule)
}