GithubSearchViewModel.kt

class GithubSearchViewModel(
    private val searchGithubUseCase: SearchGithubUseCase,
    private val likeGithubUseCase: LikeGithubRepoUseCase
) : BaseViewModel(), EmptyObservableHost {
 
    val shouldClearCurrentSearchResults = false

    private val searchEvent: MediatorLiveData<String?> = searchQuery.map {
        if (it.isNullOrBlank() || (restoredSearchQuery != null && restoredSearchQuery == it)) null
        else {
            pageNumber = 1
            shouldClearCurrentSearchResults = true
            it.trim()
        }
    }.debounce(SEARCH_DEBOUNCE_TIME, viewModelScope)
 
    val dataList: LiveData<List<GithubQuery>> = searchResult.map {
        when (it) {
            is ApiResult.Success -> {
                mIsInPullToRefreshState.postValue(false)
                if (pageNumber == 1) {
                    _onSuccessfulFirstPageFetch.postValue(Any())
                }
                if (it.data.items.isNotEmpty()) {
                    pageNumber += 1
                }

                /**
                 * Every time users update [searchQuery], they need a fresh search result.
                 * so if the [searchResult] are coming from a new searched query and not a pagination call,
                 * we clear the current list of items.
                 */
                if (shouldClearCurrentSearchResults) {
                    currentGithubQueryList.clear()
                }
                currentGithubQueryList.addAll(it.data.items)
                return@map currentGithubQueryList
            }
        }
    }
    
    fun onCardsReachTheEnd() {
        shouldClearCurrentSearchResults = false
        searchByExistingValues(true)
    }

    fun onCardsReachingTheEnd() {
        shouldClearCurrentSearchResults = false
        searchByExistingValues(true)
    }
}