package common

type Config interface {
	Name() string
	Starter() StartFct
	Children() []Config
	Add(Config)
}

type Context interface {
	Config() Config
	Parent() Context
	Services() map[string]Context
	ChildContext(Config) Context
}

type StartFct = func(Context)

// Context implementation

type context struct {
	cfg    Config
	parent Context
}

func (ctx *context) Config() Config {
	return ctx.cfg
}

func (ctx *context) Parent() Context {
	return ctx.parent
}

func (ctx *context) Services() map[string]Context {
	return ctx.parent.Services()
}

func (ctx *context) ChildContext(cfg Config) Context {
	cctx := context{cfg, ctx}
	ctx.Services()[cfg.Name()] = &cctx
	return &cctx
}

// top-level application context

type appContext struct {
	*context
	services map[string]Context
}

func (ctx *appContext) ChildContext(cfg Config) Context {
	cctx := context{cfg, ctx}
	ctx.services[cfg.Name()] = &cctx
	return &cctx
}

func (ctx *appContext) Services() map[string]Context {
	return ctx.services
}

func AppContext(cfg Config) Context {
	return &appContext{
		context:  &context{cfg, nil},
		services: map[string]Context{},
	}
}