package smshook

import (
	"encoding/json"
	"net/http"
	"sync"
	"time"

	"git.directme.in/Joren/SmsHook/ringbuffer"
)

type WebhookServer struct {
	buffer *ringbuffer.RingBuffer
	cond   *sync.Cond
	mux    *http.ServeMux
}

type WebhookPayload struct {
	Content string `json:"content"`
}

func NewWebhookServer(bufferSize int) *WebhookServer {
	mutex := sync.Mutex{}
	server := &WebhookServer{
		buffer: ringbuffer.NewRingBuffer(bufferSize),
		cond:   sync.NewCond(&mutex),
		mux:    http.NewServeMux(),
	}

	server.mux.HandleFunc("/webhook", server.webhookHandler)
	return server
}

func (s *WebhookServer) webhookHandler(w http.ResponseWriter, r *http.Request) {
	var payload WebhookPayload

	err := json.NewDecoder(r.Body).Decode(&payload)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	s.buffer.Add(payload.Content)
	s.cond.Broadcast()
}

func (s *WebhookServer) GetLastItem() (string, int) {
	return s.buffer.GetLast()
}

func (s *WebhookServer) WaitForNewItem() string {
	s.cond.L.Lock()
	s.cond.Wait()
	newItem := s.buffer.WaitForNewItem()
	s.cond.L.Unlock()
	return newItem
}

func (s *WebhookServer) WaitForNewItemWithTimeout(timeout time.Duration) (string, bool) {
	s.cond.L.Lock()
	defer s.cond.L.Unlock()

	initialPos := s.buffer.GetLastPosition()

	timedOut := false
	timer := time.AfterFunc(timeout, func() {
		s.cond.Broadcast()
		timedOut = true
	})

	for s.buffer.GetLastPosition() == initialPos {
		if timedOut {
			return "", false
		}
		s.cond.Wait()
	}

	timer.Stop()
	newItem := s.buffer.WaitForNewItem()
	return newItem, true
}

func (s *WebhookServer) Start(address string) error {
	return http.ListenAndServe(address, s.mux)
}

var Server *WebhookServer

func Init(bufferSize int, address string) {
	Server = NewWebhookServer(bufferSize)
	go func() {
		if err := Server.Start(address); err != nil {
			panic(err)
		}
	}()
}

func GetLast() (string, int) {
	return Server.GetLastItem()
}

func WaitForNew() string {
	return Server.WaitForNewItem()
}

func WaitForNewWithTimeout(timeout time.Duration) (string, bool) {
	return Server.WaitForNewItemWithTimeout(timeout)
}