diff --git a/src/config.cpp b/src/config.cpp
new file mode 100644
index 0000000..3919c91
--- /dev/null
+++ b/src/config.cpp
@@ -0,0 +1,11 @@
+#include <Adafruit_SSD1306.h>
+#include <ESPAsyncWebServer.h>
+#include <Audio.h>
+#include <Preferences.h>
+
+#include "config.h"
+
+Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
+AsyncWebServer server(80);
+Audio audio;
+Preferences preferences;
diff --git a/src/config.h b/src/config.h
new file mode 100644
index 0000000..3a90d85
--- /dev/null
+++ b/src/config.h
@@ -0,0 +1,56 @@
+#ifndef __CONFIG_H__
+#define __CONFIG_H__
+
+// Uncomment to switch to AP mode.
+// Leave commented for wifi station mode.
+// #define B_WIFI_AP
+
+// DAC
+#define I2S_DOUT 32
+#define I2S_BCLK 25
+#define I2S_LRC 27
+
+// SD CARD
+#define SPI_MISO 18
+#define SPI_MOSI 19
+#define SPI_SCK 23
+#define SD_CS 5
+
+// GPIO
+#define LED 2
+#define BUTTON 33
+
+// Screen
+#define SSD1306_NO_SPLASH
+#define SCREEN_WIDTH 128
+#define SCREEN_HEIGHT 64
+#define OLED_RESET -1
+#define SCREEN_ADDRESS 0x3C
+
+#define SCREEN_MSG_X 0
+#define SCREEN_MSG_Y 24
+
+#define LINE_LENGTH 21
+
+// Volume
+#define VOLUME_MIN 0
+#define VOLUME_MAX 21
+
+// Preference keys
+#define SELECTED_FILE "selectedFile"
+#define CURRENT_VOLUME "currentVolume"
+#define WIFI_IP "wifiIP"
+#define WIFI_SSID "wifiSSID"
+#define WIFI_PASSWORD "wifiPassword"
+
+#include <Adafruit_SSD1306.h>
+#include <ESPAsyncWebServer.h>
+#include <Audio.h>
+#include <Preferences.h>
+
+extern Adafruit_SSD1306 display;
+extern AsyncWebServer server;
+extern Audio audio;
+extern Preferences preferences;
+
+#endif
\ No newline at end of file
diff --git a/src/creds.dist.h b/src/creds.dist.h
index 62fb27c..5e0110d 100644
--- a/src/creds.dist.h
+++ b/src/creds.dist.h
@@ -1,3 +1,6 @@
 // Copy to creds.h or creds_ap.h and edit
+#ifndef __CREDS_H__
+#define __CREDS_H__
 const char *ssid = "buzzer";
 const char *password = "123456789";
+#endif
diff --git a/src/main.cpp b/src/main.cpp
index 428f897..0490053 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,361 +1,43 @@
 #include <Arduino.h>
-#include <ESPAsyncWebServer.h>
-#include <SPIFFS.h>
-#include <AsyncJson.h>
-#include <Audio.h>
-#include <SPI.h>
-#include <Wire.h>
-#include <Adafruit_GFX.h>
 #include <Adafruit_SSD1306.h>
+#include <ESPAsyncWebServer.h>
+#include <Audio.h>
 #include <Preferences.h>
-#include <AsyncElegantOTA.h>
 
-// Toggle on to switch to AP mode.
-// Leave commented for wifi station mode.
-// #define B_WIFI_AP
-
-#ifdef B_WIFI_AP
-#include "creds_ap.h"
-#else
-#include "creds.h"
-#endif
-
-// DAC
-#define I2S_DOUT 32
-#define I2S_BCLK 25
-#define I2S_LRC 27
-
-// SD CARD
-#define SPI_MISO 18
-#define SPI_MOSI 19
-#define SPI_SCK 23
-#define SD_CS 5
-
-#define LED 2
-#define BUTTON 33
-
-#define SSD1306_NO_SPLASH
-#define SCREEN_WIDTH 128
-#define SCREEN_HEIGHT 64
-#define OLED_RESET -1
-#define SCREEN_ADDRESS 0x3C
-
-#define SCREEN_MSG_X 0
-#define SCREEN_MSG_Y 24
-
-#define VOLUME_MIN 0
-#define VOLUME_MAX 21
-
-Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
-
-String selectedFile = "";
-
-AsyncWebServer server(80);
-Audio audio;
-Preferences preferences;
+#include "setup.h"
+#include "utils.h"
+#include "config.h"
 
 byte buttonLastState = HIGH;
-byte currentVolume = 12;
-
-bool fileIsValid(String fileName)
-{
-  return !fileName.startsWith(".") && (fileName.endsWith(".mp3") || fileName.endsWith(".wav"));
-}
-
-void clearMessageArea()
-{
-  display.fillRect(SCREEN_MSG_X, SCREEN_MSG_Y, SCREEN_WIDTH - SCREEN_MSG_X, SCREEN_HEIGHT - SCREEN_MSG_Y, BLACK);
-  display.setCursor(SCREEN_MSG_X, SCREEN_MSG_Y);
-}
-
-void displayText(String text)
-{
-  clearMessageArea();
-  display.println(text);
-  display.display();
-}
-
-void play()
-{
-  String path = "/" + selectedFile;
-  Serial.println("Playing file: " + path);
-  audio.stopSong();
-  audio.connecttoFS(SD, path.c_str());
-}
-
-void onStop(AsyncWebServerRequest *request)
-{
-  Serial.println("Stop playing");
-  audio.stopSong();
-  request->send(200);
-}
-
-void onPlay(AsyncWebServerRequest *request)
-{
-  play();
-  request->send(200);
-}
-
-void onStatus(AsyncWebServerRequest *request)
-{
-  Serial.println("Status");
-  AsyncResponseStream *response = request->beginResponseStream("application/json");
-
-  StaticJsonDocument<96> root;
-  root["files"]["selected"] = selectedFile.c_str();
-
-  JsonObject volume = root.createNestedObject("volume");
-  volume["current"] = currentVolume;
-  volume["canDecrease"] = currentVolume > 0;
-  volume["canIncrease"] = currentVolume < 21;
-
-  serializeJson(root, *response);
-  request->send(response);
-}
-
-void onListFiles(AsyncWebServerRequest *request)
-{
-  Serial.print("List files cursor=");
-  int cursor = 0;
-  if (request->hasParam("cursor")) {
-    String s_cursor = request->getParam("cursor")->value();
-    cursor = s_cursor.toInt();
-  }
-  Serial.println(cursor);
-
-  AsyncResponseStream *response = request->beginResponseStream("application/json");
-
-  StaticJsonDocument<512> root;
-  root["next"] = -1;
-  JsonArray files = root.createNestedArray("files");
-  File music = SD.open("/");
-  File file = music.openNextFile();
-  int index = 0;
-  while (file)
-  {
-    String fileName = file.name();
-    if (fileIsValid(fileName))
-    {
-      index++;
-      if (index >= cursor)
-        files.add(fileName);
-    }
-    file.close();
-
-    if (root.overflowed())
-    {
-      root["next"] = index;
-      break;
-    }
-    file = music.openNextFile();
-  }
-  if (root["next"] == -1) {
-    root.remove("next");
-  }
-
-  serializeJson(root, *response);
-  request->send(response);
-}
-
-void onSelectFile(AsyncWebServerRequest *request)
-{
-  Serial.print("Select file: ");
-  if (request->hasParam("fileName", true))
-  {
-    selectedFile = request->getParam("fileName", true)->value();
-    preferences.putString("selectedFile", selectedFile);
-    Serial.print(selectedFile);
-    displayText("Selectionne : " + selectedFile);
-  }
-  Serial.println();
-  onStatus(request);
-}
-
-void onChangeVolume(AsyncWebServerRequest *request)
-{
-  Serial.print("Volume: ");
-  if (request->hasParam("modifier", true))
-  {
-    String s_modifier = request->getParam("modifier", true)->value();
-    int modifier = s_modifier.toInt();
-    currentVolume += modifier;
-    if (currentVolume > VOLUME_MAX)
-      currentVolume = VOLUME_MAX;
-    else if (currentVolume < VOLUME_MIN)
-      currentVolume = VOLUME_MIN;
-    preferences.putUChar("currentVolume", currentVolume);
-    audio.setVolume(currentVolume);
-    Serial.print(currentVolume);
-    clearMessageArea();
-    display.print("Volume : ");
-    display.println(currentVolume);
-    display.display();
-  }
-  Serial.println();
-  onStatus(request);
-}
-
-void onUpload(AsyncWebServerRequest *request)
-{
-  Serial.println("onUpload");
-  request->send(200);
-}
-
-void onUploadFile(AsyncWebServerRequest *request, String filename, size_t index, uint8_t *data, size_t len, bool final)
-{
-  if (!index)
-  {
-    Serial.printf("UploadStart: %s\n", filename.c_str());
-    String filePath = "/" + filename;
-    request->_tempFile = SD.open(filePath, FILE_WRITE);
-  }
-  if (!request->_tempFile)
-  {
-    Serial.println("Couldn't open file.");
-    request->redirect("/");
-    return;
-  }
-  if (len)
-  {
-    request->_tempFile.write(data, len);
-  }
-
-  if (final)
-  {
-    Serial.printf("UploadEnd: %s, %u B\n", filename.c_str(), index + len);
-    request->_tempFile.close();
-    request->redirect("/");
-  }
-}
-
-void onNotFound(AsyncWebServerRequest *request)
-{
-  Serial.println("not found");
-  request->send(400);
-}
 
 void setup()
 {
-  // Setup serial
-  Serial.begin(115200);
+  // Setup GPIO
   pinMode(LED, OUTPUT);
   digitalWrite(LED, LOW);
-
-  preferences.begin("buzzer", false);
-
-  // Screen
-  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS))
-  {
-    Serial.println("Display init failed");
-    while (true);
-  }
-  display.clearDisplay();
-  display.setTextSize(1);
-  display.setTextColor(WHITE, BLACK);
-  display.setCursor(0, 0);
-  display.println("Chargement...");
-  display.display();
-
   pinMode(BUTTON, INPUT_PULLUP);
   buttonLastState = digitalRead(BUTTON);
 
-  // Setup SPIFFS
-  if (!SPIFFS.begin())
-  {
-    Serial.println("SPIFFS error. Exiting.");
-    display.println("Impossible d'acceder aux fichiers...");
-    display.display();
-    while (true);
-  }
+  Serial.begin(115200);
+  Serial.println("Serial... OK");
 
-  pinMode(SD_CS, OUTPUT);
-  digitalWrite(SD_CS, HIGH);
-  SPI.begin(SPI_SCK, SPI_MISO, SPI_MOSI);
+  preferences.begin("buzzer", false);
+  Serial.println("Preferences... OK");
 
-  if (!SD.begin(SD_CS))
-  {
-    Serial.println("Error talking to SD card!");
-    display.println("Impossible d'acceder a la carte SD...");
-    display.display();
-    while (true);
-  }
+  setupScreen();
+  setupSPIFFS();
+  setupSDCard();
+  setupAudio();
+  selectDefaultFile();
+  setupWifi();
+  setupWebServer();
+  diagnosticPrintln("Configuration OK!");
 
-  selectedFile = preferences.getString("selectedFile", "");
-  if (selectedFile == "" || !fileIsValid(selectedFile))
-  {
-    File root = SD.open("/");
-    File file = root.openNextFile();
-    while (file)
-    {
-      String fileName = file.name();
-      if (fileIsValid(fileName))
-      {
-        selectedFile = fileName;
-        Serial.println("Selected " + fileName);
-        display.println("Selectionne : " + fileName);
-        display.display();
-        break;
-      }
-      file.close();
-      file = root.openNextFile();
-    }
-    root.close();
-  }
-
-  display.clearDisplay();
-  display.setCursor(0, 0);
-  // Wifi
-#ifdef B_WIFI_AP
-  Serial.println("Setting up AP...");
-  WiFi.softAP(ssid, password);
-  String wifiIP = WiFi.softAPIP().toString();
-  String wifiMode = "AP";
-  display.print("Wifi: ");
-  display.println(ssid);
-  display.print("Pass: ");
-  display.println(password);
-#else
-  Serial.print("Connecting to wifi...");
-  WiFi.begin(ssid, password);
-  while (WiFi.status() != WL_CONNECTED)
-  {
-    Serial.print(".");
-    delay(500);
-  }
-  Serial.println();
-  String wifiIP = WiFi.localIP().toString();
-  String wifiMode = "client";
-#endif
-  String wifiMessage = wifiMode + " IP: " + wifiIP;
-  Serial.println(wifiMessage);
-  display.print("IP:   ");
-  display.println(wifiIP);
-  display.display();
-
-  // Server
-  server.on("/play", HTTP_GET, onPlay);
-  server.on("/stop", HTTP_GET, onStop);
-  server.on("/status", HTTP_GET, onStatus);
-  server.on("/list-files", HTTP_GET, onListFiles);
-  server.on("/select-file", HTTP_POST, onSelectFile);
-  server.on("/change-volume", HTTP_POST, onChangeVolume);
-  server.on("/upload", HTTP_POST, onUpload, onUploadFile);
-  server.onNotFound(onNotFound);
-  server.serveStatic("/", SPIFFS, "/www/").setDefaultFile("index.html");
-  AsyncElegantOTA.begin(&server);
-  server.begin();
-
-  Serial.println("Server ready!");
-  clearMessageArea();
-  display.println("Pret !");
-  display.display();
-
-  // Audio
-  audio.setPinout(I2S_BCLK, I2S_LRC, I2S_DOUT);
-  currentVolume = preferences.getUChar("currentVolume", 12);
-  audio.setVolume(currentVolume);
+  displayWifiCreds();
+  displaySelectedFile();
 
   // Setup is done, light up the LED
+  Serial.println("All setup & ready to go!");
   digitalWrite(LED, HIGH);
 }
 
diff --git a/src/setup.cpp b/src/setup.cpp
new file mode 100644
index 0000000..684af36
--- /dev/null
+++ b/src/setup.cpp
@@ -0,0 +1,140 @@
+#include <SPIFFS.h>
+#include <Wire.h>  // Required by display.begin
+#include <AsyncElegantOTA.h>
+#include <Audio.h>
+
+#ifdef B_WIFI_AP
+#include "creds_ap.h"
+#else
+#include "creds.h"
+#endif
+
+#include "config.h"
+#include "utils.h"
+#include "webHandlers.h"
+
+void setupScreen()
+{
+  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS))
+  {
+    Serial.println("Display init failed");
+    while (true);
+  }
+  display.clearDisplay();
+  display.setTextSize(1);
+  display.setTextColor(WHITE, BLACK);
+  display.setCursor(0, 0);
+  display.println("Ecran... OK");
+  display.display();
+  Serial.println("Ecran... OK");
+}
+
+void setupSPIFFS()
+{
+  diagnosticPrint("Fichiers... ");
+  if (!SPIFFS.begin())
+  {
+    Serial.println("SPIFFS error. Exiting.");
+    display.println("KO");
+    display.display();
+    while (true);
+  }
+  diagnosticPrintln("OK");
+}
+
+void setupSDCard()
+{
+  diagnosticPrint("Carte SD... ");
+  pinMode(SD_CS, OUTPUT);
+  digitalWrite(SD_CS, HIGH);
+  SPI.begin(SPI_SCK, SPI_MISO, SPI_MOSI);
+
+  if (!SD.begin(SD_CS))
+  {
+    Serial.println("Error talking to SD card!");
+    display.println("KO");
+    display.display();
+    while (true);
+  }
+  diagnosticPrintln("OK");
+}
+
+void setupAudio()
+{
+  diagnosticPrint("Audio... ");
+  audio.setPinout(I2S_BCLK, I2S_LRC, I2S_DOUT);
+  byte volume = preferences.getUChar(CURRENT_VOLUME, 12);
+  audio.setVolume(volume);
+  diagnosticPrintln("OK");
+}
+
+void selectDefaultFile()
+{
+  String linePrefix = "Son: ";
+  diagnosticPrint(linePrefix);
+  String selectedFile = preferences.getString(SELECTED_FILE, "");
+  if (selectedFile == "" || !fileIsValid(selectedFile) || !fileExists(selectedFile))
+  {
+    File root = SD.open("/");
+    File file = root.openNextFile();
+    while (file)
+    {
+      String fileName = file.name();
+      if (fileIsValid(fileName))
+      {
+        Serial.println("Selected " + fileName);
+        selectedFile = fileName;
+        preferences.putString(SELECTED_FILE, fileName);
+        break;
+      }
+      file.close();
+      file = root.openNextFile();
+    }
+    root.close();
+  }
+  diagnosticPrintln(selectedFile.substring(0, LINE_LENGTH - linePrefix.length()));
+}
+
+void setupWifi()
+{
+  diagnosticPrint("Wifi...");
+  preferences.putString(WIFI_SSID, ssid);
+  preferences.putString(WIFI_PASSWORD, password);
+#ifdef B_WIFI_AP
+  WiFi.softAP(ssid, password);
+  String wifiIP = WiFi.softAPIP().toString();
+#else
+  WiFi.begin(ssid, password);
+  while (WiFi.status() != WL_CONNECTED)
+  {
+    Serial.print(".");
+    delay(500);
+  }
+  String wifiIP = WiFi.localIP().toString();
+#endif
+  diagnosticPrintln(" OK");
+  Serial.print("IP: ");
+  Serial.println(wifiIP);
+  preferences.putString(WIFI_IP, wifiIP);
+}
+
+void setupWebServer()
+{
+  Serial.print("Server... ");
+  display.print("Serveur... ");
+  display.display();
+  server.on("/play", HTTP_GET, onPlay);
+  server.on("/stop", HTTP_GET, onStop);
+  server.on("/status", HTTP_GET, onStatus);
+  server.on("/list-files", HTTP_GET, onListFiles);
+  server.on("/select-file", HTTP_POST, onSelectFile);
+  server.on("/change-volume", HTTP_POST, onChangeVolume);
+  server.on("/upload", HTTP_POST, onUpload, onUploadFile);
+  server.onNotFound(onNotFound);
+  server.serveStatic("/", SPIFFS, "/www/").setDefaultFile("index.html");
+  AsyncElegantOTA.begin(&server);
+  server.begin();
+  Serial.println("OK");
+  display.println("OK");
+  display.display();
+}
\ No newline at end of file
diff --git a/src/setup.h b/src/setup.h
new file mode 100644
index 0000000..7ca9c24
--- /dev/null
+++ b/src/setup.h
@@ -0,0 +1,17 @@
+#ifndef __SETUP_H__
+#define __SETUP_H__
+
+#include <ESPAsyncWebServer.h>
+#include <Adafruit_SSD1306.h>
+#include <Preferences.h>
+#include <Audio.h>
+
+void setupScreen();
+void setupSPIFFS();
+void setupSDCard();
+void setupAudio();
+void selectDefaultFile();
+void setupWifi();
+void setupWebServer();
+
+#endif
diff --git a/src/utils.cpp b/src/utils.cpp
new file mode 100644
index 0000000..4488e12
--- /dev/null
+++ b/src/utils.cpp
@@ -0,0 +1,87 @@
+#include <Arduino.h>
+#include <Audio.h>
+#include <Preferences.h>
+#include <Adafruit_SSD1306.h>
+#include <SD.h>
+
+#include "config.h"
+
+bool fileIsValid(String fileName)
+{
+  return !fileName.startsWith(".") && (fileName.endsWith(".mp3") || fileName.endsWith(".wav"));
+}
+
+bool fileExists(String fileName)
+{
+  return SD.exists("/" + fileName);
+}
+
+void clearMessageArea()
+{
+  display.fillRect(SCREEN_MSG_X, SCREEN_MSG_Y, SCREEN_WIDTH - SCREEN_MSG_X, SCREEN_HEIGHT - SCREEN_MSG_Y, BLACK);
+  display.setCursor(SCREEN_MSG_X, SCREEN_MSG_Y);
+}
+
+void displayText(String text)
+{
+  clearMessageArea();
+  display.println(text);
+  display.display();
+}
+
+void play()
+{
+  String selectedFile = preferences.getString(SELECTED_FILE);
+  String path = "/" + selectedFile;
+  Serial.println("Playing file: " + path);
+  audio.stopSong();
+  audio.connecttoFS(SD, path.c_str());
+}
+
+
+void diagnosticPrint(String text)
+{
+  Serial.print(text);
+  display.print(text);
+  display.display();
+}
+void diagnosticPrintln(String text)
+{
+  Serial.println(text);
+  display.println(text);
+  display.display();
+}
+
+void displayWifiCreds()
+{
+  display.clearDisplay();
+  display.setCursor(0, 0);
+
+  String ssid = preferences.getString(WIFI_SSID, "");
+  display.print("Wifi: ");
+  display.println(ssid);
+
+  display.print("Pass: ");
+#ifdef B_WIFI_AP
+  String password = preferences.getString(WIFI_PASSWORD, "");
+  display.println(password);
+#else
+  display.println("****");
+#endif
+
+  display.print("IP: ");
+  String ip = preferences.getString(WIFI_IP, "");
+  display.println(ip);
+  display.display();
+}
+
+void displaySelectedFile()
+{
+  String prefix = "Son: ";
+  displayText(prefix + preferences.getString(SELECTED_FILE, "").substring(0, LINE_LENGTH - prefix.length()));
+}
+
+void displayVolume() {
+    String volume = String(preferences.getUChar(CURRENT_VOLUME));
+    displayText("Volume: " + volume);
+}
\ No newline at end of file
diff --git a/src/utils.h b/src/utils.h
new file mode 100644
index 0000000..29d4abf
--- /dev/null
+++ b/src/utils.h
@@ -0,0 +1,20 @@
+#ifndef __UTILS_H__
+#define __UTILS_H__
+
+#include <Arduino.h>
+#include <Adafruit_SSD1306.h>
+#include <Preferences.h>
+
+bool fileIsValid(String fileName);
+bool fileExists(String fileName);
+void clearMessageArea();
+void displayText(String text);
+void play();
+
+void displayWifiCreds();
+void displaySelectedFile();
+
+void diagnosticPrint(String text);
+void diagnosticPrintln(String text);
+
+#endif
diff --git a/src/webHandlers.cpp b/src/webHandlers.cpp
new file mode 100644
index 0000000..ca6a6eb
--- /dev/null
+++ b/src/webHandlers.cpp
@@ -0,0 +1,161 @@
+#include <Arduino.h>
+#include <ESPAsyncWebServer.h>
+#include <AsyncJson.h>
+#include <ArduinoJson.h>
+#include <Adafruit_SSD1306.h>
+#include <Preferences.h>
+#include <SD.h>
+
+#include "config.h"
+#include "utils.h"
+
+void onStop(AsyncWebServerRequest *request)
+{
+  Serial.println("Stop playing");
+  audio.stopSong();
+  request->send(200);
+}
+
+void onPlay(AsyncWebServerRequest *request)
+{
+  play();
+  request->send(200);
+}
+
+void onStatus(AsyncWebServerRequest *request)
+{
+  Serial.println("Status");
+  AsyncResponseStream *response = request->beginResponseStream("application/json");
+
+  StaticJsonDocument<96> root;
+  root["files"]["selected"] = preferences.getString(SELECTED_FILE, "").c_str();
+
+  JsonObject volume = root.createNestedObject("volume");
+  byte currentVolume = preferences.getUChar(CURRENT_VOLUME);
+  volume["current"] = currentVolume;
+  volume["canDecrease"] = currentVolume > 0;
+  volume["canIncrease"] = currentVolume < 21;
+
+  serializeJson(root, *response);
+  request->send(response);
+}
+
+void onListFiles(AsyncWebServerRequest *request)
+{
+  Serial.print("List files cursor=");
+  int cursor = 0;
+  if (request->hasParam("cursor")) {
+    String s_cursor = request->getParam("cursor")->value();
+    cursor = s_cursor.toInt();
+  }
+  Serial.println(cursor);
+
+  AsyncResponseStream *response = request->beginResponseStream("application/json");
+
+  StaticJsonDocument<512> root;
+  root["next"] = -1;
+  JsonArray files = root.createNestedArray("files");
+  File music = SD.open("/");
+  File file = music.openNextFile();
+  int index = 0;
+  while (file)
+  {
+    String fileName = file.name();
+    if (fileIsValid(fileName))
+    {
+      index++;
+      if (index >= cursor)
+        files.add(fileName);
+    }
+    file.close();
+
+    if (root.overflowed())
+    {
+      root["next"] = index;
+      break;
+    }
+    file = music.openNextFile();
+  }
+  if (root["next"] == -1) {
+    root.remove("next");
+  }
+
+  serializeJson(root, *response);
+  request->send(response);
+}
+
+void onSelectFile(AsyncWebServerRequest *request)
+{
+  Serial.print("Select file: ");
+  if (request->hasParam("fileName", true))
+  {
+    String selectedFile = request->getParam("fileName", true)->value();
+    preferences.putString(SELECTED_FILE, selectedFile);
+    Serial.print(selectedFile);
+    displaySelectedFile();
+  }
+  Serial.println();
+  onStatus(request);
+}
+
+void onChangeVolume(AsyncWebServerRequest *request)
+{
+  Serial.print("Volume: ");
+  if (request->hasParam("modifier", true))
+  {
+    String s_modifier = request->getParam("modifier", true)->value();
+    int modifier = s_modifier.toInt();
+    byte currentVolume = preferences.getUChar(CURRENT_VOLUME);
+    currentVolume += modifier;
+    if (currentVolume > VOLUME_MAX)
+      currentVolume = VOLUME_MAX;
+    else if (currentVolume < VOLUME_MIN)
+      currentVolume = VOLUME_MIN;
+    preferences.putUChar(CURRENT_VOLUME, currentVolume);
+    audio.setVolume(currentVolume);
+    Serial.print(currentVolume);
+    String s_volume = String(currentVolume);
+    displayText("Volume : " + s_volume);
+  }
+  Serial.println();
+  onStatus(request);
+}
+
+void onUpload(AsyncWebServerRequest *request)
+{
+  Serial.println("onUpload");
+  request->send(200);
+}
+
+void onUploadFile(AsyncWebServerRequest *request, String filename, size_t index, uint8_t *data, size_t len, bool final)
+{
+  if (!index)
+  {
+    Serial.printf("UploadStart: %s\n", filename.c_str());
+    String filePath = "/" + filename;
+    request->_tempFile = SD.open(filePath, FILE_WRITE);
+  }
+  if (!request->_tempFile)
+  {
+    Serial.println("Couldn't open file.");
+    request->redirect("/");
+    return;
+  }
+  if (len)
+  {
+    request->_tempFile.write(data, len);
+  }
+
+  if (final)
+  {
+    Serial.printf("UploadEnd: %s, %u B\n", filename.c_str(), index + len);
+    request->_tempFile.close();
+    request->redirect("/");
+  }
+}
+
+void onNotFound(AsyncWebServerRequest *request)
+{
+  Serial.println("not found");
+  request->send(400);
+}
diff --git a/src/webHandlers.h b/src/webHandlers.h
new file mode 100644
index 0000000..cecc260
--- /dev/null
+++ b/src/webHandlers.h
@@ -0,0 +1,20 @@
+#ifndef __MAIN_H__
+#define __MAIN_H__
+
+#include <Arduino.h>
+#include <ESPAsyncWebServer.h>
+#include <Adafruit_SSD1306.h>
+#include <Preferences.h>
+
+
+void onStop(AsyncWebServerRequest *request);
+void onPlay(AsyncWebServerRequest *request);
+void onStatus(AsyncWebServerRequest *request);
+void onListFiles(AsyncWebServerRequest *request);
+void onSelectFile(AsyncWebServerRequest *request);
+void onChangeVolume(AsyncWebServerRequest *request);
+void onUpload(AsyncWebServerRequest *request);
+void onUploadFile(AsyncWebServerRequest *request, String filename, size_t index, uint8_t *data, size_t len, bool final);
+void onNotFound(AsyncWebServerRequest *request);
+
+#endif
\ No newline at end of file