package container

import (
	"context"
	"errors"

	"github.com/go-chi/chi/middleware"
	goweb "gitlab.com/wpetit/goweb/middleware"
	"gitlab.com/wpetit/goweb/service"
)

const (
	// KeyServiceContainer is the context key associated with the ServiceContainer value
	KeyServiceContainer goweb.ContextKey = "serviceContainer"
)

// ErrInvalidServiceContainer is returned when no service container
// could be found on the given context
var ErrInvalidServiceContainer = errors.New("invalid service container")

// From retrieves the service container from the given context
func From(ctx context.Context) (*service.Container, error) {
	container, ok := ctx.Value(KeyServiceContainer).(*service.Container)
	if !ok {
		return nil, ErrInvalidServiceContainer
	}
	return container, nil
}

// Must retrieves the service container from the given context or panics otherwise
func Must(ctx context.Context) *service.Container {
	container, err := From(ctx)
	if err != nil {
		panic(err)
	}
	return container
}

// ServiceContainer expose the given service container as a context value
// on the HTTP requests
func ServiceContainer(container *service.Container) goweb.Middleware {
	return middleware.WithValue(KeyServiceContainer, container)
}

// WithContainer returns a new context.Context with the given *service.Container
// attached.
func WithContainer(ctx context.Context, container *service.Container) context.Context {
	return context.WithValue(ctx, KeyServiceContainer, container)
}