create a Room database for local contacts

app/build.gradle

@@ -1,6 +1,7 @@
 apply plugin: 'com.android.application'
 apply plugin: 'kotlin-android'
 apply plugin: 'kotlin-android-extensions'
+apply plugin: 'kotlin-kapt'
 
 android {
     compileSdkVersion 28
@@ -45,6 +46,10 @@ dependencies {
     implementation 'joda-time:joda-time:2.9.9'
     implementation 'androidx.constraintlayout:constraintlayout:2.0.0-alpha2'
     implementation 'com.googlecode.ez-vcard:ez-vcard:0.10.4'
+
+    kapt "androidx.room:room-compiler:2.0.0"
+    implementation "androidx.room:room-runtime:2.0.0"
+    annotationProcessor "androidx.room:room-compiler:2.0.0"
 }
 
 Properties props = new Properties()

app/src/main/kotlin/com/simplemobiletools/contacts/pro/databases/ContactsDatabase.kt

@@ -0,0 +1,61 @@
+package com.simplemobiletools.contacts.pro.databases
+
+import android.content.Context
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+import androidx.sqlite.db.SupportSQLiteDatabase
+import com.simplemobiletools.contacts.pro.helpers.getEmptyLocalContact
+import com.simplemobiletools.contacts.pro.interfaces.ContactsDao
+import com.simplemobiletools.contacts.pro.models.LocalContact
+import com.simplemobiletools.contacts.pro.objects.MyExecutor
+import java.util.concurrent.Executors
+
+@Database(entities = [(LocalContact::class)], version = 1)
+abstract class ContactsDatabase : RoomDatabase() {
+
+    abstract fun ContactsDao(): ContactsDao
+
+    companion object {
+        private val FIRST_CONTACT_ID = 1000000L
+
+        private var db: ContactsDatabase? = null
+
+        fun getInstance(context: Context): ContactsDatabase {
+            if (db == null) {
+                synchronized(ContactsDatabase::class) {
+                    if (db == null) {
+                        db = Room.databaseBuilder(context.applicationContext, ContactsDatabase::class.java, "local_contacts.db")
+                                .setQueryExecutor(MyExecutor.myExecutor)
+                                .addCallback(object : Callback() {
+                                    override fun onCreate(db: SupportSQLiteDatabase) {
+                                        super.onCreate(db)
+                                        increaseAutoIncrementId()
+                                    }
+                                })
+                                .build()
+                        db!!.openHelper.setWriteAheadLoggingEnabled(true)
+                    }
+                }
+            }
+            return db!!
+        }
+
+        fun destroyInstance() {
+            db = null
+        }
+
+        // start autoincrement ID from FIRST_CONTACT_ID to avoid conflicts
+        // Room doesn't seem to have a built in way for it, so just create a contact and delete it
+        private fun increaseAutoIncrementId() {
+            Executors.newSingleThreadExecutor().execute {
+                val emptyContact = getEmptyLocalContact()
+                emptyContact.id = FIRST_CONTACT_ID
+                db!!.ContactsDao().apply {
+                    insertOrUpdate(emptyContact)
+                    deleteContactIds(FIRST_CONTACT_ID.toString())
+                }
+            }
+        }
+    }
+}

app/src/main/kotlin/com/simplemobiletools/contacts/pro/extensions/Context.kt

@@ -15,7 +15,9 @@ import com.simplemobiletools.contacts.pro.BuildConfig
 import com.simplemobiletools.contacts.pro.R
 import com.simplemobiletools.contacts.pro.activities.EditContactActivity
 import com.simplemobiletools.contacts.pro.activities.ViewContactActivity
+import com.simplemobiletools.contacts.pro.databases.ContactsDatabase
 import com.simplemobiletools.contacts.pro.helpers.*
+import com.simplemobiletools.contacts.pro.interfaces.ContactsDao
 import com.simplemobiletools.contacts.pro.models.Contact
 import java.io.File
 
@@ -23,6 +25,8 @@ val Context.config: Config get() = Config.newInstance(applicationContext)
 
 val Context.dbHelper: DBHelper get() = DBHelper.newInstance(applicationContext)
 
+val Context.contactsDB: ContactsDao get() = ContactsDatabase.getInstance(applicationContext).ContactsDao()
+
 fun Context.viewContact(contact: Contact) {
     Intent(applicationContext, ViewContactActivity::class.java).apply {
         putExtra(CONTACT_ID, contact.id)

app/src/main/kotlin/com/simplemobiletools/contacts/pro/helpers/Constants.kt

@@ -1,6 +1,7 @@
 package com.simplemobiletools.contacts.pro.helpers
 
 import android.provider.ContactsContract.CommonDataKinds
+import com.simplemobiletools.contacts.pro.models.LocalContact
 
 // shared prefs
 const val SHOW_CONTACT_THUMBNAILS = "show_contact_thumbnails"
@@ -119,3 +120,5 @@ val localAccountTypes = arrayListOf("vnd.sec.contact.phone",
 const val TELEGRAM_PACKAGE = "org.telegram.messenger"
 const val SIGNAL_PACKAGE = "org.thoughtcrime.securesms"
 const val WHATSAPP_PACKAGE = "com.whatsapp"
+
+fun getEmptyLocalContact() = LocalContact(0, "", "", "", "", "", "", null, "", "", "", false, "", "", "", "", "", "", "")

app/src/main/kotlin/com/simplemobiletools/contacts/pro/interfaces/ContactsDao.kt

@@ -0,0 +1,22 @@
+package com.simplemobiletools.contacts.pro.interfaces
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+import com.simplemobiletools.contacts.pro.models.LocalContact
+
+@Dao
+interface ContactsDao {
+    @Query("SELECT * FROM contacts")
+    fun getContacts(): List<LocalContact>
+
+    @Query("SELECT * FROM contacts WHERE id = :id")
+    fun getContactWithId(id: Long): LocalContact
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    fun insertOrUpdate(contact: LocalContact)
+
+    @Query("DELETE FROM contacts WHERE id IN (:ids)")
+    fun deleteContactIds(ids: String)
+}

app/src/main/kotlin/com/simplemobiletools/contacts/pro/models/LocalContact.kt

@@ -0,0 +1,33 @@
+package com.simplemobiletools.contacts.pro.models
+
+import androidx.room.ColumnInfo
+import androidx.room.Entity
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "contacts", indices = [(Index(value = ["id"], unique = true))])
+data class LocalContact(
+        @PrimaryKey(autoGenerate = true) var id: Long?,
+        @ColumnInfo(name = "prefix") var prefix: String,
+        @ColumnInfo(name = "first_name") var firstName: String,
+        @ColumnInfo(name = "middle_name") var middleName: String,
+        @ColumnInfo(name = "surname") var surname: String,
+        @ColumnInfo(name = "suffix") var suffix: String,
+        @ColumnInfo(name = "nickname") var nickname: String,
+        @ColumnInfo(name = "photo", typeAffinity = ColumnInfo.BLOB) var photo: ByteArray?,
+        @ColumnInfo(name = "phone_numbers") var phoneNumbers: String,
+        @ColumnInfo(name = "emails") var emails: String,
+        @ColumnInfo(name = "events") var events: String,
+        @ColumnInfo(name = "starred") var starred: Boolean,
+        @ColumnInfo(name = "addresses") var addresses: String,
+        @ColumnInfo(name = "notes") var notes: String,
+        @ColumnInfo(name = "groups") var groups: String,
+        @ColumnInfo(name = "company") var company: String,
+        @ColumnInfo(name = "job_position") var jobPosition: String,
+        @ColumnInfo(name = "websites") var websites: String,
+        @ColumnInfo(name = "ims") var ims: String) {
+
+    companion object {
+        private const val serialVersionUID = -655314977575622L
+    }
+}

app/src/main/kotlin/com/simplemobiletools/contacts/pro/objects/MyExecutor.kt

@@ -0,0 +1,7 @@
+package com.simplemobiletools.contacts.pro.objects
+
+import java.util.concurrent.Executors
+
+object MyExecutor {
+    val myExecutor = Executors.newSingleThreadExecutor()
+}