Improve tag emoji assignment

data/database/build.gradle.kts

@@ -49,6 +49,7 @@ dependencies {
     ksp(libs.androidx.roomcompiler)
     api(libs.androidx.room)
     implementation(libs.koin.android)
+    implementation(libs.emoji4j)
 
     implementation(project(":core:i18n"))
     implementation(project(":core:ktx"))

data/database/src/main/java/de/mm20/launcher2/database/AppDatabase.kt

@@ -36,6 +36,7 @@ import de.mm20.launcher2.database.migrations.Migration_22_23
 import de.mm20.launcher2.database.migrations.Migration_23_24
 import de.mm20.launcher2.database.migrations.Migration_24_25
 import de.mm20.launcher2.database.migrations.Migration_25_26
+import de.mm20.launcher2.database.migrations.Migration_26_27
 import de.mm20.launcher2.database.migrations.Migration_6_7
 import de.mm20.launcher2.database.migrations.Migration_7_8
 import de.mm20.launcher2.database.migrations.Migration_8_9
@@ -55,7 +56,7 @@ import java.util.UUID
         SearchActionEntity::class,
         ThemeEntity::class,
         PluginEntity::class,
-    ], version = 26, exportSchema = true
+    ], version = 27, exportSchema = true
 )
 @TypeConverters(ComponentNameConverter::class)
 abstract class AppDatabase : RoomDatabase() {
@@ -154,6 +155,7 @@ abstract class AppDatabase : RoomDatabase() {
                         Migration_23_24(),
                         Migration_24_25(),
                         Migration_25_26(),
+                        Migration_26_27(),
                     ).build()
             if (_instance == null) _instance = instance
             return instance

data/database/src/main/java/de/mm20/launcher2/database/migrations/Migration_26_27.kt

@@ -0,0 +1,72 @@
+package de.mm20.launcher2.database.migrations
+
+import android.content.ContentValues
+import android.database.sqlite.SQLiteDatabase
+import android.util.Log
+import androidx.room.migration.Migration
+import androidx.sqlite.db.SupportSQLiteDatabase
+import com.sigpwned.emoji4j.core.Grapheme
+import com.sigpwned.emoji4j.core.GraphemeMatcher
+import de.mm20.launcher2.ktx.jsonObjectOf
+
+class Migration_26_27 : Migration(26, 27) {
+    override fun migrate(db: SupportSQLiteDatabase) {
+        Log.d("Tags-Migration", "Migrating tags")
+        db.query("SELECT DISTINCT value FROM CustomAttributes WHERE type = 'tag'").use { cursor ->
+            while (cursor.moveToNext()) {
+                val oldName = cursor.getString(0)
+                val (emoji, newName) = oldName.splitLeadingEmoji()
+
+                if (emoji != null) {
+                    db.update(
+                        "CustomAttributes",
+                        SQLiteDatabase.CONFLICT_FAIL,
+                        ContentValues().apply {
+                            put("value", newName)
+                        }, "type = 'tag' AND value = ?",
+                        arrayOf(oldName)
+                    )
+                    db.insert(
+                        "CustomAttributes",
+                        SQLiteDatabase.CONFLICT_REPLACE,
+                        ContentValues().apply {
+                            put("key", "tag://$newName")
+                            put("type", "icon")
+                            put("value", jsonObjectOf(
+                                "type" to "custom_text_icon",
+                                "text" to emoji,
+                                "color" to 0,
+                            ).toString())
+                        }
+                    )
+                    db.update(
+                        "Searchable",
+                        SQLiteDatabase.CONFLICT_IGNORE,
+                        ContentValues().apply {
+                            put("key", "tag://$newName")
+                            put("searchable", jsonObjectOf(
+                                "tag" to newName
+                            ).toString())
+                        },
+                        "key = ?",
+                        arrayOf("tag://$oldName")
+                    )
+                }
+            }
+        }
+    }
+
+    fun String.splitLeadingEmoji(): Pair<String?, String> {
+        val matcher = GraphemeMatcher(this)
+        if (!matcher.find()) return null to this.trim()
+        val grapheme = matcher.grapheme()
+        if (grapheme?.type == Grapheme.Type.EMOJI && matcher.start() == 0) {
+            val end = matcher.end()
+            val emoji = this.substring(0, end)
+            val tagName = this.substring(end).takeIf { it.isNotBlank() }
+            if (tagName == null) return emoji to emoji
+            return emoji to tagName
+        }
+        return null to this.trim()
+    }
+}