애플리케이션 이름 변경 & gradle 의존성 일부 수정

.gitignore

@@ -130,3 +130,4 @@ replay_pid*
 # Kotlin Gradle plugin data, see https://kotlinlang.org/docs/whatsnew20.html#new-directory-for-kotlin-data-in-gradle-projects
 .kotlin/
 gcp/
+library

build.gradle.kts

@@ -20,31 +20,28 @@ repositories {
 	mavenCentral()
 }
 
-extra["springCloudGcpVersion"] = "7.1.0"
-extra["springCloudVersion"] = "2025.0.0"
-
 dependencies {
 	implementation("org.springframework.boot:spring-boot-starter-data-jpa")
 	implementation("org.springframework.boot:spring-boot-starter-mail")
 	implementation("org.springframework.boot:spring-boot-starter-validation")
 	implementation("org.springframework.boot:spring-boot-starter-web")
+
 	implementation("com.fasterxml.jackson.module:jackson-module-kotlin")
-	implementation("com.google.cloud:spring-cloud-gcp-starter")
+	implementation("io.github.oshai:kotlin-logging-jvm:7.0.3")
 	implementation("org.jetbrains.kotlin:kotlin-reflect")
+
 	implementation("com.google.cloud:google-cloud-texttospeech:2.68.0")
 	implementation("org.apache.poi:poi:5.4.1")
+	implementation("net.bramp.ffmpeg:ffmpeg:0.8.0")
+
 	runtimeOnly("com.mysql:mysql-connector-j")
+	runtimeOnly("com.h2database:h2")
+
+	testRuntimeOnly("org.junit.platform:junit-platform-launcher")
 	testImplementation("org.springframework.boot:spring-boot-starter-test")
 	testImplementation("org.jetbrains.kotlin:kotlin-test-junit5")
-	runtimeOnly("com.h2database:h2")
+	testImplementation("io.kotest:kotest-runner-junit5:5.9.1")
-	testRuntimeOnly("org.junit.platform:junit-platform-launcher")
+	testImplementation("io.kotest.extensions:kotest-extensions-spring:1.3.0")
-}
-
-dependencyManagement {
-	imports {
-		mavenBom("com.google.cloud:spring-cloud-gcp-dependencies:${property("springCloudGcpVersion")}")
-		mavenBom("org.springframework.cloud:spring-cloud-dependencies:${property("springCloudVersion")}")
-	}
 }
 
 kotlin {

src/main/kotlin/com/sangdol/text_to_speech/ConvertSingleTextRequest.kt

@@ -0,0 +1,8 @@
+package com.sangdol.text_to_speech
+
+data class ConvertSingleTextRequest(
+    val text: String,
+    val type: VoiceType,
+    val speakingRate: Double,
+    val order: Int
+)

src/main/kotlin/com/sangdol/text_to_speech/FfmpegUtils.kt

@@ -0,0 +1,94 @@
+package com.sangdol.text_to_speech
+
+import net.bramp.ffmpeg.FFmpeg
+import net.bramp.ffmpeg.FFmpegExecutor
+import net.bramp.ffmpeg.builder.FFmpegBuilder
+import org.springframework.stereotype.Component
+import java.io.File
+
+private const val FFMPEG_PATH: String = "/opt/homebrew/bin/ffmpeg"
+private const val SILENCE_AUDIO_PATH: String = "library/silences"
+
+private fun convertSilenceAudioFilePath(durationMs: Long) = "$SILENCE_AUDIO_PATH/silence-${durationMs}ms.mp3"
+
+@Component
+class FfmpegUtils(
+    private val ffmpegExecutor: FFmpegExecutor = FFmpegExecutor(FFmpeg(FFMPEG_PATH))
+) {
+
+    fun createSilenceAudio(durationMs: Long) {
+        val durationSeconds = durationMs / 1000.0
+        val outputFile = convertSilenceAudioFilePath(durationMs)
+
+        val command = listOf(
+            FFMPEG_PATH,
+            "-y",
+            "-f", "lavfi",
+            "-i", "anullsrc=r=44100:cl=stereo",
+            "-t", durationSeconds.toString(),
+            "-acodec", "mp3",
+            outputFile
+        )
+
+        val process = ProcessBuilder(command)
+            .redirectErrorStream(true)
+            .start()
+
+        process.inputStream.bufferedReader().forEachLine { println(it) }
+        process.waitFor()
+            .takeUnless { exitCode -> exitCode == 0 }
+            ?: throw RuntimeException("FFmpeg failed with exit code ${process.exitValue()}")
+    }
+
+    fun mergeAudioWithInterval(intervalMs: Long, targetDirectory: String, saveDirectory: String, fileName: String) {
+        val targetDir = File(targetDirectory).also { validateIsValidFileDirectory(it) }
+        val fileNameRegex = """(\d+)(.*)""".toRegex()
+
+        if (intervalMs > 0 && !File(convertSilenceAudioFilePath(intervalMs)).exists()) {
+            createSilenceAudio(intervalMs)
+        }
+
+        val files = targetDir.listFiles().sortedBy { it ->
+            val matchResult: MatchResult = fileNameRegex.find(it.name)
+                ?: throw IllegalStateException("Invalid filename-convention")
+            matchResult.groups[1]!!.value.toInt()
+        }.map { "$it" }
+
+        val inputs = mutableListOf<String>()
+        files.forEachIndexed { idx, file ->
+            inputs.add(file)
+            if (intervalMs > 0L && (idx != files.lastIndex)) {
+                inputs.add("library/silences/silence-${intervalMs}ms.mp3")
+            }
+        }
+
+        val builder = FFmpegBuilder()
+
+        inputs.forEach { filePath -> builder.addInput(filePath) }
+
+        val filterInputs = inputs.indices.joinToString("") { idx -> "[$idx:a]" }
+        val filterComplex = "$filterInputs concat=n=${inputs.size}:v=0:a=1[out]"
+
+        builder.setComplexFilter(filterComplex)
+            .addOutput("$saveDirectory/$fileName")
+            .setAudioCodec("mp3")
+            .addExtraArgs("-map", "[out]")
+            .done()
+
+        ffmpegExecutor.createJob(builder).run()
+    }
+
+    private fun validateIsValidFileDirectory(dir: File) {
+        if (!dir.exists()) {
+            throw IllegalArgumentException("Directory not found: $dir")
+        }
+        if (!dir.isDirectory) {
+            throw IllegalArgumentException("Path is not a directory: $dir")
+        }
+        val fileList = dir.listFiles()
+
+        if (fileList == null || fileList.isEmpty()) {
+            throw IllegalArgumentException("Directory is null or empty: $dir")
+        }
+    }
+}

src/main/kotlin/com/sangdol/text_to_speech/GoogleTtsConfig.kt

@@ -0,0 +1,44 @@
+package com.sangdol.text_to_speech
+
+import com.google.cloud.texttospeech.v1.TextToSpeechClient
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+
+@Configuration
+class GoogleTtsConfig {
+
+    @Bean
+    fun textToSpeechClient(): TextToSpeechClient = TextToSpeechClient.create()
+}
+
+enum class TtsLanguageCode(
+    val code: String
+) {
+    ENGLISH_US("en-US")
+}
+
+sealed interface VoiceType {
+    val identifier: String
+    val name: String
+}
+
+enum class Neural2MaleVoice(
+    override val identifier: String,
+): VoiceType {
+    TYPE_A("en-US-Neural2-A"),
+    TYPE_D("en-US-Neural2-D"),
+    TYPE_I("en-US-Neural2-I"),
+    TYPE_J("en-US-Neural2-J"),
+    ;
+}
+
+enum class Neural2FemaleVoice(
+    override val identifier: String
+): VoiceType {
+    TYPE_C("en-US-Neural2-C"),
+    TYPE_E("en-US-Neural2-E"),
+    TYPE_F("en-US-Neural2-F"),
+    TYPE_G("en-US-Neural2-G"),
+    TYPE_H("en-US-Neural2-H"),
+    ;
+}

src/main/kotlin/com/sangdol/text_to_speech/SampleCreateTestRunner.kt

@@ -0,0 +1,91 @@
+package com.sangdol.text_to_speech
+
+import io.github.oshai.kotlinlogging.KLogger
+import io.github.oshai.kotlinlogging.KotlinLogging
+import org.springframework.boot.CommandLineRunner
+import org.springframework.context.annotation.Profile
+import org.springframework.stereotype.Component
+
+private val log: KLogger = KotlinLogging.logger {}
+
+@Profile("none")
+@Component
+class SampleCreateTestRunner(
+    private val singleTextConverter: SingleTextConverter
+) : CommandLineRunner {
+
+    override fun run(vararg args: String?) {
+        listOf(
+            ConvertSingleTextRequest(
+                text = "Did you find the book you were looking for?",
+                type = Neural2FemaleVoice.TYPE_C,
+                speakingRate = 1.0,
+                order = 1
+            ),
+            ConvertSingleTextRequest(
+                text = "Yes, it’s right here. It’s exactly what I need for my project.",
+                type = Neural2MaleVoice.TYPE_A,
+                speakingRate = 1.0,
+                order = 2
+            ),
+            ConvertSingleTextRequest(
+                text = "Great. Do you need help with anything else?",
+                type = Neural2FemaleVoice.TYPE_E,
+                speakingRate = 1.0,
+                order = 3
+            ),
+            ConvertSingleTextRequest(
+                text = "Could you show me how to use the copy machine?",
+                type = Neural2MaleVoice.TYPE_D,
+                speakingRate = 1.0,
+                order = 4
+            ),
+            ConvertSingleTextRequest(
+                text = "Sure, it’s over there in the corner. Let me guide you.",
+                type = Neural2FemaleVoice.TYPE_F,
+                speakingRate = 1.0,
+                order = 5
+            ),
+        ).forEach {
+            val type: VoiceType = it.type
+            val filePath = "library/sample-scripts-1/${it.order}(${genderString(type)}-${type.name}).mp3"
+            singleTextConverter.convert(it, filePath)
+        }
+
+        listOf(
+            ConvertSingleTextRequest(
+                text = "I want to pick up a new hobby, but I’m not sure what to try.",
+                type = Neural2FemaleVoice.TYPE_C,
+                speakingRate = 1.0,
+                order = 1
+            ),
+            ConvertSingleTextRequest(
+                text = "Have you thought about gardening? ",
+                type = Neural2MaleVoice.TYPE_A,
+                speakingRate = 1.0,
+                order = 2
+            ),
+            ConvertSingleTextRequest(
+                text = "Gardening? I’ve never tried it before. What can I grow?",
+                type = Neural2FemaleVoice.TYPE_E,
+                speakingRate = 1.0,
+                order = 3
+            ),
+            ConvertSingleTextRequest(
+                text = "You can start with some flowers for your balcony.",
+                type = Neural2MaleVoice.TYPE_D,
+                speakingRate = 1.0,
+                order = 4
+            ),
+        ).forEach {
+            val type: VoiceType = it.type
+            val filePath = "library/sample-scripts-1/${it.order}(${genderString(type)}-${type.name}).mp3"
+            singleTextConverter.convert(it, filePath)
+        }
+    }
+
+    private fun genderString(type: VoiceType) = when(type) {
+        is Neural2MaleVoice -> "male"
+        is Neural2FemaleVoice -> "female"
+    }
+}

src/main/kotlin/com/sangdol/text_to_speech/SingleTextConverter.kt

@@ -0,0 +1,44 @@
+package com.sangdol.text_to_speech
+
+import com.google.cloud.texttospeech.v1.*
+import com.google.protobuf.ByteString
+import org.springframework.stereotype.Component
+import java.io.File
+import java.io.FileOutputStream
+
+@Component
+class SingleTextConverter(
+    private val ttsClient: TextToSpeechClient
+) {
+    fun convert(
+        request: ConvertSingleTextRequest,
+        filePath: String,
+        language: TtsLanguageCode = TtsLanguageCode.ENGLISH_US,
+        encodingType: AudioEncoding = AudioEncoding.MP3
+    ) {
+        val synthesisInput = SynthesisInput.newBuilder()
+            .setText(request.text)
+            .build()
+
+        val voiceOptions = VoiceSelectionParams.newBuilder()
+            .setLanguageCode(language.code)
+            .setName(request.type.identifier)
+            .build()
+
+        val audioConfig = AudioConfig.newBuilder()
+            .setAudioEncoding(encodingType)
+            .setSpeakingRate(request.speakingRate)
+            .build()
+
+        val synthesizeResponse: SynthesizeSpeechResponse = ttsClient.synthesizeSpeech(synthesisInput, voiceOptions, audioConfig)
+        val content: ByteString = synthesizeResponse.audioContent
+
+        val file = File(filePath).also {
+            it.parentFile
+                .takeIf { dir -> !dir.exists() }
+                ?.mkdirs()
+        }
+
+        FileOutputStream(file).use { it.write(content.toByteArray()) }
+    }
+}

src/main/kotlin/com/sangdol/text_to_speech/TTSApplication.kt

@@ -4,8 +4,8 @@ import org.springframework.boot.autoconfigure.SpringBootApplication
 import org.springframework.boot.runApplication
 
 @SpringBootApplication
-class TextToSpeechApplication
+class TTSApplication
 
 fun main(args: Array<String>) {
-	runApplication<TextToSpeechApplication>(*args)
+	runApplication<TTSApplication>(*args)
 }