Record and send voice messages (#1596)

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Co-authored-by: ElementBot <benoitm+elementbot@element.io>

libraries/voicerecorder/api/build.gradle.kts

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+plugins {
+    id("io.element.android-library")
+    alias(libs.plugins.anvil)
+}
+
+android {
+    namespace = "io.element.android.libraries.voicerecorder.api"
+}
+
+anvil {
+    generateDaggerFactories.set(true)
+}
+
+dependencies {
+    implementation(libs.androidx.annotationjvm)
+    implementation(libs.coroutines.core)
+}

libraries/voicerecorder/api/src/main/kotlin/io/element/android/libraries/voicerecorder/api/VoiceRecorder.kt

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+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.element.android.libraries.voicerecorder.api
+
+import android.Manifest
+import androidx.annotation.RequiresPermission
+import kotlinx.coroutines.flow.StateFlow
+
+/**
+ * Audio recorder which records audio to opus/ogg files.
+ */
+interface VoiceRecorder {
+    /**
+     * Start a recording.
+     *
+     * Call [stopRecord] to stop the recording and release resources.
+     */
+    @RequiresPermission(Manifest.permission.RECORD_AUDIO)
+    suspend fun startRecord()
+
+    /**
+     * Stop the current recording.
+     *
+     * Call [deleteRecording] to delete any recorded audio.
+     *
+     * @param cancelled If true, the recording is deleted.
+     */
+    suspend fun stopRecord(
+        cancelled: Boolean = false
+    )
+
+    /**
+     * Stop the current recording and delete the output file.
+     */
+    suspend fun deleteRecording()
+
+    /**
+     * The current state of the recorder.
+     */
+    val state: StateFlow<VoiceRecorderState>
+}

libraries/voicerecorder/api/src/main/kotlin/io/element/android/libraries/voicerecorder/api/VoiceRecorderState.kt

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+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.element.android.libraries.voicerecorder.api
+
+import java.io.File
+
+sealed class VoiceRecorderState {
+    /**
+     * The recorder is idle and not recording.
+     */
+    data object Idle : VoiceRecorderState()
+
+    /**
+     * The recorder is currently recording.
+     *
+     * @property level The current audio level of the recording as a fraction of 1.
+     */
+    data class Recording(val level: Double) : VoiceRecorderState()
+
+    /**
+     * The recorder has finished recording.
+     *
+     * @property file The recorded file.
+     * @property mimeType The mime type of the file.
+     */
+    data class Finished(
+        val file: File,
+        val mimeType: String,
+    ) : VoiceRecorderState()
+}