package main

// Queue for pending authentication requests

import (
	"math/rand"
	"sync"
	"time"

	"github.com/oklog/ulid"
)

type AuthenticationMap struct {
	requestMap      map[string]*AuthRequest
	app             *App
	requestMapMutex *sync.RWMutex
}

// Returns empty string when no request by that id is present
func (q *AuthenticationMap) GetRequestByID(ID string) *AuthRequest {
	q.requestMapMutex.RLock()

	req, ok := q.requestMap[ID]

	q.requestMapMutex.RUnlock()

	if !ok {
		return nil
	}

	return req
}

func (q *AuthenticationMap) QueueRequest(r *AuthRequest) error {
	t := time.Unix(1000000, 0)
	entropy := ulid.Monotonic(rand.New(rand.NewSource(t.UnixNano())), 0)

	ulidID := ulid.MustNew(ulid.Timestamp(t), entropy)
	ID := ulidID.String()

	err := r.SetId(ID)

	if err != nil {
		return err
	}

	r.Queued = time.Now()

	q.requestMapMutex.Lock()
	q.requestMap[ID] = r
	q.requestMapMutex.Unlock()

	(*q.app.Logger).Info("Queued request by id: ", ID)

	return nil
}

func (q *AuthenticationMap) Init() {
	q.requestMap = make(map[string]*AuthRequest)
	q.requestMapMutex = &sync.RWMutex{}
	q.startRequestMapCleaner()
}

func (q *AuthenticationMap) startRequestMapCleaner() {
	go func() {
		for _ = range time.Tick(10 * time.Minute) {
			q.requestMapMutex.Lock()

			for key, req := range q.requestMap {
				// If the request has been queued for more than 30
				// minutes, it's time to delete it.
				if req.Queued.Add(30 * time.Minute).Before(time.Now()) {
					(*q.app.Logger).Info("Deleting inactive request with id: ", req.ID)

					req.Cancel()
					delete(q.requestMap, key)
				}

			}

			q.requestMapMutex.Unlock()
		}
	}()
}

func (q *AuthenticationMap) Delete(ID string) {
	q.requestMapMutex.Lock()
	delete(q.requestMap, ID)
	q.requestMapMutex.Unlock()
}