fix follow{ing,ers} for mastodon, start fixing viewmodel brokenness

app/src/main/java/org/pixeldroid/app/MainActivity.kt

@@ -73,21 +73,20 @@ class MainActivity : BaseActivity() {
 
             setupDrawer()
 
-            val tabs: List<() -> Fragment> = listOf(
+            val tabs: List<Fragment> = listOf(
-                    {
+
                         PostFeedFragment<HomeStatusDatabaseEntity>()
                                 .apply {
                                     arguments = Bundle().apply { putBoolean("home", true) }
                                 }
-                    },
+                    ,
-                    { SearchDiscoverFragment() },
+                    SearchDiscoverFragment() ,
-                    { CameraFragment() },
+                    CameraFragment() ,
-                    { NotificationsFragment() },
+                    NotificationsFragment() ,
-                    {
+
                         PostFeedFragment<PublicFeedStatusDatabaseEntity>()
                                 .apply {
                                     arguments = Bundle().apply { putBoolean("home", false) }
-                                }
                     }
             )
             setupTabs(tabs)
@@ -270,10 +269,10 @@ class MainActivity : BaseActivity() {
     }
 
 
-    private fun setupTabs(tab_array: List<() -> Fragment>){
+    private fun setupTabs(tab_array: List<Fragment>){
         binding.viewPager.adapter = object : FragmentStateAdapter(this) {
             override fun createFragment(position: Int): Fragment {
-                return tab_array[position]()
+                return tab_array[position]
             }
 
             override fun getItemCount(): Int {

app/src/main/java/org/pixeldroid/app/posts/feeds/cachedFeeds/notifications/NotificationsFragment.kt

@@ -53,10 +53,10 @@ class NotificationsFragment : CachedFeedFragment<Notification>() {
         // get the view model
         @Suppress("UNCHECKED_CAST")
         viewModel = ViewModelProvider(
-            this,
+            requireActivity(),
             ViewModelFactory(db, db.notificationDao(), NotificationsRemoteMediator(apiHolder, db))
         )
-            .get(FeedViewModel::class.java) as FeedViewModel<Notification>
+            .get("notifications", FeedViewModel::class.java) as FeedViewModel<Notification>
 
         launch()
         initSearch()

app/src/main/java/org/pixeldroid/app/posts/feeds/cachedFeeds/postFeeds/PostFeedFragment.kt

@@ -20,6 +20,7 @@ import org.pixeldroid.app.posts.feeds.cachedFeeds.ViewModelFactory
 import org.pixeldroid.app.utils.api.objects.FeedContentDatabase
 import org.pixeldroid.app.utils.api.objects.Status
 import org.pixeldroid.app.utils.displayDimensionsInPx
+import kotlin.properties.Delegates
 
 
 /**
@@ -32,14 +33,17 @@ class PostFeedFragment<T: FeedContentDatabase>: CachedFeedFragment<T>() {
 
     private lateinit var mediator: RemoteMediator<Int, T>
     private lateinit var dao: FeedContentDao<T>
+    private var home by Delegates.notNull<Boolean>()
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
         adapter = PostsAdapter(requireContext().displayDimensionsInPx())
 
+        home = requireArguments().get("home") as Boolean
+
         @Suppress("UNCHECKED_CAST")
-        if (requireArguments().get("home") as Boolean){
+        if (home){
             mediator = HomeFeedRemoteMediator(apiHolder, db) as RemoteMediator<Int, T>
             dao = db.homePostDao() as FeedContentDao<T>
         }
@@ -59,8 +63,8 @@ class PostFeedFragment<T: FeedContentDatabase>: CachedFeedFragment<T>() {
 
         // get the view model
         @Suppress("UNCHECKED_CAST")
-        viewModel = ViewModelProvider(this, ViewModelFactory(db, dao, mediator))
+        viewModel = ViewModelProvider(requireActivity(), ViewModelFactory(db, dao, mediator))
-            .get(FeedViewModel::class.java) as FeedViewModel<T>
+            .get(if(home) "home" else "public", FeedViewModel::class.java) as FeedViewModel<T>
 
         launch()
         initSearch()

app/src/main/java/org/pixeldroid/app/posts/feeds/uncachedFeeds/UncachedFeedFragment.kt

@@ -65,9 +65,6 @@ open class UncachedFeedFragment<T: FeedContent> : BaseFragment() {
             binding.motionLayout, binding.errorLayout, adapter)
 
         binding.swipeRefreshLayout.setOnRefreshListener {
-            //It shouldn't be necessary to also retry() in addition to refresh(),
-            //but if we don't do this, reloads after an error fail immediately...
-            adapter.retry()
             adapter.refresh()
         }
 

app/src/main/java/org/pixeldroid/app/posts/feeds/uncachedFeeds/accountLists/AccountListFragment.kt

@@ -52,7 +52,7 @@ class AccountListFragment : UncachedFeedFragment<Account>() {
 
         // get the view model
         @Suppress("UNCHECKED_CAST")
-        viewModel = ViewModelProvider(this, ViewModelFactory(
+        viewModel = ViewModelProvider(requireActivity(), ViewModelFactory(
             FollowersContentRepository(
                 apiHolder.setToCurrentUser(),
                 id,
@@ -60,7 +60,7 @@ class AccountListFragment : UncachedFeedFragment<Account>() {
             )
         )
         )
-            .get(FeedViewModel::class.java) as FeedViewModel<Account>
+            .get("accountList", FeedViewModel::class.java) as FeedViewModel<Account>
 
         launch()
         initSearch()

app/src/main/java/org/pixeldroid/app/posts/feeds/uncachedFeeds/accountLists/FollowersPagingSource.kt

@@ -41,25 +41,22 @@ class FollowersPagingSource(
                 throw HttpException(response)
             }
 
-            val nextPosition: String = if(response.headers()["Link"] != null){
+            val nextPosition: String = response.headers()["Link"]
-                //Header is of the form:
+                // Header is of the form:
                 // Link: <https://mastodon.social/api/v1/accounts/1/followers?limit=2&max_id=7628164>; rel="next", <https://mastodon.social/api/v1/accounts/1/followers?limit=2&since_id=7628165>; rel="prev"
                 // So we want the first max_id value. In case there are arguments after
                 // the max_id in the URL, we make sure to stop at the first '?'
-                response.headers()["Link"]
+                ?.substringAfter("max_id=", "")
-                    .orEmpty()
+                ?.substringBefore('?', "")
-                    .substringAfter("max_id=", "")
+                ?.substringBefore('>', "")
-                    .substringBefore('?', "")
+
-                    .substringBefore('>', "")
+                ?: // No Link header, so we just increment the position value (Pixelfed case)
-            } else {
-                // No Link header, so we just increment the position value
                 (position?.toBigIntegerOrNull() ?: 1.toBigInteger()).inc().toString()
-            }
 
             LoadResult.Page(
                 data = accounts,
                 prevKey = null,
-                nextKey = if (accounts.isEmpty()) null else nextPosition
+                nextKey = if (accounts.isEmpty() or nextPosition.isEmpty()) null else nextPosition
             )
         } catch (exception: IOException) {
             LoadResult.Error(exception)
@@ -68,8 +65,5 @@ class FollowersPagingSource(
         }
     }
 
-    override fun getRefreshKey(state: PagingState<String, Account>): String? =
+    override fun getRefreshKey(state: PagingState<String, Account>): String? = null
-        state.anchorPosition?.run {
-            state.closestItemToPosition(this)?.id
-        }
 }

app/src/main/java/org/pixeldroid/app/posts/feeds/uncachedFeeds/search/SearchAccountFragment.kt

@@ -37,14 +37,14 @@ class SearchAccountFragment : UncachedFeedFragment<Account>() {
 
         // get the view model
         @Suppress("UNCHECKED_CAST")
-        viewModel = ViewModelProvider(this, ViewModelFactory(
+        viewModel = ViewModelProvider(requireActivity(), ViewModelFactory(
                 SearchContentRepository<Account>(
                     apiHolder.setToCurrentUser(),
                     Results.SearchType.accounts,
                     query
                 )
             )
-        ).get(FeedViewModel::class.java) as FeedViewModel<Account>
+        ).get("searchAccounts", FeedViewModel::class.java) as FeedViewModel<Account>
 
         launch()
         initSearch()

app/src/main/java/org/pixeldroid/app/posts/feeds/uncachedFeeds/search/SearchHashtagFragment.kt

@@ -44,7 +44,7 @@ class SearchHashtagFragment : UncachedFeedFragment<Tag>() {
 
         // get the view model
         @Suppress("UNCHECKED_CAST")
-        viewModel = ViewModelProvider(this, ViewModelFactory(
+        viewModel = ViewModelProvider(requireActivity(), ViewModelFactory(
             SearchContentRepository<Tag>(
                 apiHolder.setToCurrentUser(),
                 Results.SearchType.hashtags,
@@ -52,7 +52,7 @@ class SearchHashtagFragment : UncachedFeedFragment<Tag>() {
             )
         )
         )
-            .get(FeedViewModel::class.java) as FeedViewModel<Tag>
+            .get("searchHashtag", FeedViewModel::class.java) as FeedViewModel<Tag>
 
         launch()
         initSearch()

app/src/main/java/org/pixeldroid/app/posts/feeds/uncachedFeeds/search/SearchPagingSource.kt

@@ -46,8 +46,9 @@ class SearchPagingSource<T: FeedContent>(
         }
     }
 
-    override fun getRefreshKey(state: PagingState<Int, T>): Int? =
+    /**
-        state.anchorPosition?.run {
+     * FIXME if implemented with [PagingState.anchorPosition], this breaks refreshes? How is this
-            state.closestItemToPosition(this)?.id?.toIntOrNull()
+     * supposed to work?
-        }
+     */
+    override fun getRefreshKey(state: PagingState<Int, T>): Int? = null
 }

app/src/main/java/org/pixeldroid/app/posts/feeds/uncachedFeeds/search/SearchPostsFragment.kt

@@ -41,7 +41,7 @@ class SearchPostsFragment : UncachedFeedFragment<Status>() {
 
         // get the view model
         @Suppress("UNCHECKED_CAST")
-        viewModel = ViewModelProvider(this, ViewModelFactory(
+        viewModel = ViewModelProvider(requireActivity(), ViewModelFactory(
             SearchContentRepository<Status>(
                 apiHolder.setToCurrentUser(),
                 Results.SearchType.statuses,
@@ -49,7 +49,7 @@ class SearchPostsFragment : UncachedFeedFragment<Status>() {
             )
         )
         )
-            .get(FeedViewModel::class.java) as FeedViewModel<Status>
+            .get("searchPosts", FeedViewModel::class.java) as FeedViewModel<Status>
 
         launch()
         initSearch()