viewModel.getPosts()

fun getPosts() {
    if (postsOutcome.value == null)
        repo.fetchPosts(compositeDisposable)
}

val postFetchOutcome: PublishSubject<Outcome<List<PostWithUser>>> = PublishSubject.create<Outcome<List<PostWithUser>>>()

private val TAG = "ListRepository"

fun fetchPosts(compositeDisposable: CompositeDisposable) {
    postFetchOutcome.loading(true)
    //Observe changes to the db
    postDb.postDao().getAll()
            .performOnBackOutOnMain()
            .subscribe({ retailers ->
                postFetchOutcome.success(retailers)
                if (remoteFetch)
                    refreshPosts(compositeDisposable)
                remoteFetch = false
            }, { error -> handleError(error) }
            .addTo(compositeDisposable)
    )
}

fun refreshPosts(compositeDisposable: CompositeDisposable) {
    postFetchOutcome.loading(true)
        Flowable.zip(
                postService.getUsers(),
                postService.getPosts(),
                BiFunction<List<User>, List<Post>, Unit> { t1, t2 -> saveUsersAndPosts(t1, t2) }
        )
                .performOnBackOutOnMain()
                .subscribe({}, { error -> handleError(error) })
                .addTo(compositeDisposable)
}

private fun saveUsersAndPosts(users: List<User>, posts: List<Post>) {
    Completable.fromAction {
        postDb.userDao().insertAll(users)
        postDb.postDao().insertAll(posts)
    }
            .performOnBackOutOnMain()
            .subscribe()
}

private fun handleError(error: Throwable) {
    postFetchOutcome.failed(error)
}

val postsOutcome: LiveData<Outcome<List<Post>>> by lazy {
    //Convert publish subject to livedata
    repo.postFetchOutcome.toLiveData(compositeDisposable)
}

viewModel.postsOutcome.observe(this, Observer<Outcome<List<Post>>> { outcome ->
        when (outcome) {

            is Outcome.Progress -> srlPosts.isRefreshing = outcome.loading

            is Outcome.Success -> {
                Log.d(TAG, "initiateDataListener: Successfully loaded data")
                adapter.setData(outcome.data)
            }

            is Outcome.Failure -> {
                if (outcome.e is IOException)
                    Toast.makeText(context, R.string.need_internet_posts, Toast.LENGTH_LONG).show()
                else
                    Toast.makeText(context, R.string.failed_post_try_again, Toast.LENGTH_LONG).show()
            }

        }
    })