package serverevents

import (
	di "git.apihub24.de/admin/generic-di"
	"sync"
	"time"
)

func init() {
	di.Injectable(newContext)
}

type IContext interface {
	SetId(id string)
	GetId() string
	Set(key string, data any)
	Get(key string) (any, bool)
	RemoveMetaData(key string)
	CleanupIn(lifetime time.Duration)
	Dispatch(eventName string, data any, filter func(c IContext) bool)
	IsCaller(c IContext) bool
}

type context struct {
	id       string
	metadata map[string]any
	timer    *time.Timer
	emitter  IEventEmitter
	mutex    sync.RWMutex
}

func newContext() IContext {
	return &context{
		id:       "",
		metadata: make(map[string]any),
		timer:    nil,
		emitter:  di.Inject[IEventEmitter](),
		mutex:    sync.RWMutex{},
	}
}

func (context *context) SetId(id string) {
	context.mutex.Lock()
	defer context.mutex.Unlock()

	if context.timer != nil {
		context.timer.Stop()
		context.timer = nil
	}
	context.id = id
}

func (context *context) GetId() string {
	return context.id
}

func (context *context) IsCaller(c IContext) bool {
	return context.id == c.GetId()
}

func (context *context) Set(key string, data any) {
	context.mutex.Lock()
	defer context.mutex.Unlock()

	context.metadata[key] = data
}

func (context *context) Get(key string) (any, bool) {
	context.mutex.RLock()
	defer context.mutex.RUnlock()

	v, ok := context.metadata[key]
	return v, ok
}

func (context *context) RemoveMetaData(key string) {
	context.mutex.Lock()
	defer context.mutex.Unlock()

	if _, ok := context.metadata[key]; ok {
		delete(context.metadata, key)
	}
}

func (context *context) CleanupIn(lifetime time.Duration) {
	context.mutex.Lock()
	defer context.mutex.Unlock()

	if context.timer != nil {
		context.timer.Stop()
	}
	context.timer = time.NewTimer(lifetime)
	go func(currentId string) {
		<-context.timer.C

		context.mutex.Lock()
		defer context.mutex.Unlock()

		if context.timer != nil {
			di.Destroy[IContext](context.id)
			context.timer = nil
		}
	}(context.id)
}

func (context *context) Dispatch(eventName string, data any, filter func(c IContext) bool) {
	ev := Event{
		Type:          eventName,
		Data:          data,
		IsBackendOnly: filter == nil,
		Filter:        filter,
	}
	context.emitter.Emit(ev)
}