Query instance for toot character limit (#571)

* Query instance for toot character limit
Fixes #393

* Move maximumTootCharacters to instance field

* Add caching for maximum toot characters, expanding on the emoji list storage

* Update formatting per review feedback

* Fix compose activity tests

* Rename mastodon api point for nicer interaction with kotlin

* Default emoji list to empty list instead of null, to appease json converters in failure cases

* Use empty list helper

* Fix database migration

app/src/main/java/com/keylesspalace/tusky/ComposeActivity.java

@@ -31,6 +31,7 @@ import android.graphics.PorterDuff;
 import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.AsyncTask;
+import android.os.Build;
 import android.os.Bundle;
 import android.os.Environment;
 import android.os.Parcel;
@@ -85,11 +86,12 @@ import com.keylesspalace.tusky.adapter.MentionAutoCompleteAdapter;
 import com.keylesspalace.tusky.adapter.OnEmojiSelectedListener;
 import com.keylesspalace.tusky.db.AccountEntity;
 import com.keylesspalace.tusky.db.AccountManager;
-import com.keylesspalace.tusky.db.EmojiListEntity;
+import com.keylesspalace.tusky.db.InstanceEntity;
 import com.keylesspalace.tusky.di.Injectable;
 import com.keylesspalace.tusky.entity.Account;
 import com.keylesspalace.tusky.entity.Attachment;
 import com.keylesspalace.tusky.entity.Emoji;
+import com.keylesspalace.tusky.entity.Instance;
 import com.keylesspalace.tusky.entity.Status;
 import com.keylesspalace.tusky.network.MastodonApi;
 import com.keylesspalace.tusky.network.ProgressRequestBody;
@@ -124,6 +126,7 @@ import java.io.InputStream;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.Date;
 import java.util.Iterator;
 import java.util.List;
@@ -200,6 +203,8 @@ public final class ComposeActivity
     private int currentFlags;
     private Uri photoUploadUri;
     private int savedTootUid = 0;
+    private List<Emoji> emojiList;
+    private int maximumTootCharacters = STATUS_CHARACTER_LIMIT;
 
     private SaveTootHelper saveTootHelper;
 
@@ -222,6 +227,7 @@ public final class ComposeActivity
         emojiButton = findViewById(R.id.composeEmojiButton);
         hideMediaToggle = findViewById(R.id.composeHideMediaButton);
         emojiView = findViewById(R.id.emojiView);
+        emojiList = Collections.emptyList();
 
         saveTootHelper = new SaveTootHelper(TuskyApplication.getDB().tootDao(), this);
 
@@ -258,6 +264,37 @@ public final class ComposeActivity
                     getString(R.string.compose_active_account_description,
                             activeAccount.getFullName()));
 
+            mastodonApi.getInstance().enqueue(new Callback<Instance>() {
+                @Override
+                public void onResponse(@NonNull Call<Instance> call, @NonNull Response<Instance> response) {
+                    if (response.isSuccessful() && response.body().getMaxTootChars() != null) {
+                        maximumTootCharacters = response.body().getMaxTootChars();
+                        updateVisibleCharactersLeft();
+                        cacheInstanceMetadata(activeAccount);
+                    }
+                }
+
+                @Override
+                public void onFailure(@NonNull Call<Instance> call, @NonNull Throwable t) {
+                    Log.w(TAG, "error loading instance data", t);
+                    loadCachedInstanceMetadata(activeAccount);
+                }
+            });
+
+            mastodonApi.getCustomEmojis().enqueue(new Callback<List<Emoji>>() {
+                @Override
+                public void onResponse(@NonNull Call<List<Emoji>> call, @NonNull Response<List<Emoji>> response) {
+                    emojiList = response.body();
+                    enableButton(emojiButton, true, emojiList.size() > 0);
+                    cacheInstanceMetadata(activeAccount);
+                }
+
+                @Override
+                public void onFailure(@NonNull Call<List<Emoji>> call, @NonNull Throwable t) {
+                    Log.w(TAG, "error loading custom emojis", t);
+                    loadCachedInstanceMetadata(activeAccount);
+                }
+            });
         } else {
             // do not do anything when not logged in, activity will be finished in super.onCreate() anyway
             return;
@@ -277,34 +314,6 @@ public final class ComposeActivity
 
         enableButton(emojiButton, false, false);
 
-        mastodonApi.getCustomEmojis().enqueue(new Callback<List<Emoji>>() {
-            @Override
-            public void onResponse(@NonNull Call<List<Emoji>> call, @NonNull Response<List<Emoji>> response) {
-                List<Emoji> emojiList = response.body();
-
-                if (emojiList != null) {
-                    emojiView.setAdapter(new EmojiAdapter(emojiList, ComposeActivity.this));
-
-                    enableButton(emojiButton, true, emojiList.size() > 0);
-
-                    EmojiListEntity emojiListEntity = new EmojiListEntity(activeAccount.getDomain(), emojiList);
-
-                    TuskyApplication.getDB().emojiListDao().insertOrReplace(emojiListEntity);
-                }
-            }
-
-            @Override
-            public void onFailure(@NonNull Call<List<Emoji>> call, @NonNull Throwable t) {
-                Log.w(TAG, "error loading custom emojis", t);
-                EmojiListEntity emojiListEntity = TuskyApplication.getDB().emojiListDao().loadEmojisForInstance(activeAccount.getDomain());
-
-                if(emojiListEntity != null) {
-                    emojiView.setAdapter(new EmojiAdapter(emojiListEntity.getEmojiList(), ComposeActivity.this));
-                    enableButton(emojiButton, true, emojiListEntity.getEmojiList().size() > 0);
-                }
-            }
-        });
-
         // Setup the interface buttons.
         tootButton.setOnClickListener(v -> onSendClicked());
         pickButton.setOnClickListener(v -> openPickDialog());
@@ -761,7 +770,7 @@ public final class ComposeActivity
     }
 
     private void updateVisibleCharactersLeft() {
-        int charactersLeft = STATUS_CHARACTER_LIMIT - textEditor.length();
+        int charactersLeft = maximumTootCharacters - textEditor.length();
         if (statusHideText) {
             charactersLeft -= contentWarningEditor.length();
         }
@@ -914,7 +923,7 @@ public final class ComposeActivity
         if (characterCount <= 0 && mediaQueued.size()==0) {
             textEditor.setError(getString(R.string.error_empty));
             enableButtons();
-        } else if (characterCount <= STATUS_CHARACTER_LIMIT) {
+        } else if (characterCount <= maximumTootCharacters) {
             sendStatus(contentText, visibility, sensitive, spoilerText);
 
         } else {
@@ -1423,6 +1432,27 @@ public final class ComposeActivity
         textEditor.getText().insert(textEditor.getSelectionStart(), ":"+shortcode+": ");
     }
 
+    private void loadCachedInstanceMetadata(@NotNull AccountEntity activeAccount)
+    {
+        InstanceEntity instanceEntity = TuskyApplication.getDB().instanceDao().loadMetadataForInstance(activeAccount.getDomain());
+
+        if(instanceEntity != null) {
+            Integer max = instanceEntity.getMaximumTootCharacters();
+            maximumTootCharacters = (max == null ? STATUS_CHARACTER_LIMIT : max.intValue());
+            emojiList = instanceEntity.getEmojiList();
+            if (emojiList != null) {
+                emojiView.setAdapter(new EmojiAdapter(emojiList, ComposeActivity.this));
+                enableButton(emojiButton, true, emojiList.size() > 0);
+            }
+        }
+    }
+
+    private void cacheInstanceMetadata(@NotNull AccountEntity activeAccount)
+    {
+        InstanceEntity instanceEntity = new InstanceEntity(activeAccount.getDomain(), emojiList, maximumTootCharacters);
+        TuskyApplication.getDB().instanceDao().insertOrReplace(instanceEntity);
+    }
+
     public static final class QueuedMedia {
         Type type;
         ProgressImageView preview;

app/src/main/java/com/keylesspalace/tusky/TuskyApplication.java

@@ -79,7 +79,7 @@ public class TuskyApplication extends Application implements HasActivityInjector
 
         db = Room.databaseBuilder(getApplicationContext(), AppDatabase.class, "tuskyDB")
                 .allowMainThreadQueries()
-                .addMigrations(AppDatabase.MIGRATION_2_3, AppDatabase.MIGRATION_3_4, AppDatabase.MIGRATION_4_5, AppDatabase.MIGRATION_5_6)
+                .addMigrations(AppDatabase.MIGRATION_2_3, AppDatabase.MIGRATION_3_4, AppDatabase.MIGRATION_4_5, AppDatabase.MIGRATION_5_6, AppDatabase.MIGRATION_6_7)
                 .build();
         accountManager = new AccountManager(db);
         serviceLocator = new ServiceLocator() {

app/src/main/java/com/keylesspalace/tusky/db/AppDatabase.java

@@ -25,12 +25,12 @@ import android.support.annotation.NonNull;
  * DB version & declare DAO
  */
 
-@Database(entities = {TootEntity.class, AccountEntity.class, EmojiListEntity.class}, version = 6, exportSchema = false)
+@Database(entities = {TootEntity.class, AccountEntity.class, InstanceEntity.class}, version = 7, exportSchema = false)
 public abstract class AppDatabase extends RoomDatabase {
 
     public abstract TootDao tootDao();
     public abstract AccountDao accountDao();
-    public abstract EmojiListDao emojiListDao();
+    public abstract InstanceDao instanceDao();
 
     public static final Migration MIGRATION_2_3 = new Migration(2, 3) {
         @Override
@@ -82,4 +82,13 @@ public abstract class AppDatabase extends RoomDatabase {
             database.execSQL("CREATE TABLE IF NOT EXISTS `EmojiListEntity` (`instance` TEXT NOT NULL, `emojiList` TEXT NOT NULL, PRIMARY KEY(`instance`))");
         }
     };
+
+    public static final Migration MIGRATION_6_7 = new Migration(6, 7) {
+        @Override
+        public void migrate(@NonNull SupportSQLiteDatabase database) {
+            database.execSQL("CREATE TABLE IF NOT EXISTS `InstanceEntity` (`instance` TEXT NOT NULL, `emojiList` TEXT, `maximumTootCharacters` INTEGER, PRIMARY KEY(`instance`))");
+            database.execSQL("INSERT OR REPLACE INTO `InstanceEntity` SELECT `instance`,`emojiList`,NULL FROM `EmojiListEntity`;");
+            database.execSQL("DROP TABLE `EmojiListEntity`;");
+        }
+    };
 }

app/src/main/java/com/keylesspalace/tusky/db/InstanceDao.kt

@@ -21,11 +21,10 @@ import android.arch.persistence.room.OnConflictStrategy
 import android.arch.persistence.room.Query
 
 @Dao
-interface EmojiListDao {
+interface InstanceDao {
     @Insert(onConflict = OnConflictStrategy.REPLACE)
-    fun insertOrReplace(emojiList: EmojiListEntity)
-
-    @Query("SELECT * FROM EmojiListEntity WHERE instance = :instance LIMIT 1")
-    fun loadEmojisForInstance(instance: String): EmojiListEntity?
+    fun insertOrReplace(instance: InstanceEntity)
 
+    @Query("SELECT * FROM InstanceEntity WHERE instance = :instance LIMIT 1")
+    fun loadMetadataForInstance(instance: String): InstanceEntity?
 }

app/src/main/java/com/keylesspalace/tusky/db/InstanceEntity.kt

@@ -25,8 +25,10 @@ import com.keylesspalace.tusky.entity.Emoji
 
 @Entity
 @TypeConverters(Converters::class)
-data class EmojiListEntity(@field:PrimaryKey var instance: String,
-                           val emojiList: List<Emoji>)
+data class InstanceEntity(
+        @field:PrimaryKey var instance: String,
+        val emojiList: List<Emoji>?,
+        val maximumTootCharacters: Int?)
 
 
 class Converters {

app/src/main/java/com/keylesspalace/tusky/entity/Instance.kt

@@ -0,0 +1,46 @@
+/* Copyright 2018 Levi Bard
+ *
+ * This file is a part of Tusky.
+ *
+ * This program is free software; you can redistribute it and/or modify it under the terms of the
+ * GNU General Public License as published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * Tusky is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+ * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with Tusky; if not,
+ * see <http://www.gnu.org/licenses>. */
+
+package com.keylesspalace.tusky.entity
+
+import com.google.gson.annotations.SerializedName
+import java.util.*
+
+data class Instance (
+        val uri: String,
+        val title: String,
+        val description: String,
+        val email: String,
+        val version: String,
+        val urls: Map<String,String>,
+        val stats: Map<String,Int>?,
+        val thumbnail: String?,
+        val languages: List<String>,
+        @SerializedName("contact_account") val contactAccount: Account,
+        @SerializedName("max_toot_chars") val maxTootChars: Int?
+) {
+    override fun hashCode(): Int {
+        return uri.hashCode()
+    }
+
+    override fun equals(other: Any?): Boolean {
+        if (other !is Instance) {
+            return false
+        }
+        val instance = other as Instance?
+        return instance?.uri.equals(uri)
+    }
+}
+

app/src/main/java/com/keylesspalace/tusky/network/MastodonApi.java

@@ -23,6 +23,7 @@ import com.keylesspalace.tusky.entity.AppCredentials;
 import com.keylesspalace.tusky.entity.Attachment;
 import com.keylesspalace.tusky.entity.Card;
 import com.keylesspalace.tusky.entity.Emoji;
+import com.keylesspalace.tusky.entity.Instance;
 import com.keylesspalace.tusky.entity.MastoList;
 import com.keylesspalace.tusky.entity.Notification;
 import com.keylesspalace.tusky.entity.Relationship;
@@ -270,4 +271,7 @@ public interface MastodonApi {
 
     @GET("/api/v1/custom_emojis")
     Call<List<Emoji>> getCustomEmojis();
+
+    @GET("api/v1/instance")
+    Call<Instance> getInstance();
 }

app/src/test/java/com/keylesspalace/tusky/ComposeActivityTest.kt

@@ -20,6 +20,7 @@ import android.widget.EditText
 import com.keylesspalace.tusky.db.AccountEntity
 import com.keylesspalace.tusky.db.AccountManager
 import com.keylesspalace.tusky.entity.Emoji
+import com.keylesspalace.tusky.entity.Instance
 import com.keylesspalace.tusky.network.MastodonApi
 import okhttp3.Request
 import org.junit.Assert.assertFalse
@@ -103,6 +104,28 @@ class ComposeActivityTest {
 
             override fun enqueue(callback: Callback<List<Emoji>>?) {}
         })
+        `when`(apiMock.instance).thenReturn(object: Call<Instance> {
+            override fun isExecuted(): Boolean {
+                return false
+            }
+            override fun clone(): Call<Instance> {
+                throw Error("not implemented")
+            }
+            override fun isCanceled(): Boolean {
+                throw Error("not implemented")
+            }
+            override fun cancel() {
+                throw Error("not implemented")
+            }
+            override fun execute(): Response<Instance> {
+                throw Error("not implemented")
+            }
+            override fun request(): Request {
+                throw Error("not implemented")
+            }
+
+            override fun enqueue(callback: Callback<Instance>?) {}
+        })
 
         activity.mastodonApi = apiMock
         activity.accountManager = accountManagerMock