package hwsauth

import (
	"context"
	"database/sql"
)

type authenticatedModel[T Model] struct {
	model T
	fresh int64
}

func getNil[T Model]() T {
	var result T
	return result
}

type Model interface {
	ID() int
}

type ContextLoader[T Model] func(ctx context.Context) T

type LoadFunc[T Model] func(tx *sql.Tx, id int) (T, error)

// Return a new context with the user added in
func setAuthenticatedModel[T Model](ctx context.Context, m *authenticatedModel[T]) context.Context {
	return context.WithValue(ctx, "hwsauth context key authenticated-model", m)
}

// Retrieve a user from the given context. Returns nil if not set
func getAuthorizedModel[T Model](ctx context.Context) *authenticatedModel[T] {
	model, ok := ctx.Value("hwsauth context key authenticated-model").(*authenticatedModel[T])
	if !ok {
		return nil
	}
	return model
}

func (auth *Authenticator[T]) CurrentModel(ctx context.Context) T {
	model := getAuthorizedModel[T](ctx)
	if model == nil {
		return getNil[T]()
	}
	return model.model
}