#include <Arduino.h>
#include <WiFi.h>
#include <HTTPClient.h>
#include <Audio.h>
#include <Wire.h>
#include <ArduinoJson.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// ==== 配置 ==== //
const char* ssid = "Y0ur_SSID";
const char* password = "Y0ur_pass";
const char* music_api = "http://www.expamle.com/get_music_list.php";

// OLED 設置
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// 按鈕引腳
#define BUTTON_PLAY 34
#define BUTTON_NEXT 35

// I2S 引腳
#define I2S_DOUT 25
#define I2S_BCLK 26
#define I2S_LRC  27

Audio audio;
bool isPlaying = false;

// 音樂信息結構體
struct MusicItem {
  String url;
  String title;
};

// ========== 獲取音樂 JSON ==========
MusicItem fetchMusicURL() {
  MusicItem result;
  HTTPClient http;
  http.begin(music_api);
  int httpCode = http.GET();

  if (httpCode == 200) {
    String payload = http.getString();
    http.end();

    StaticJsonDocument<1024> doc;
    DeserializationError error = deserializeJson(doc, payload);
    if (!error && doc.is<JsonArray>()) {
      JsonObject obj = doc[0];
      result.url = obj["url"].as<String>();
      result.title = obj["title"].as<String>();
    }
  } else {
    http.end();
  }

  return result;
}

// ========== OLED 顯示函數 ==========
void showStatus(const String& line1, const String& line2 = "") {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 10);
  display.println(line1);
  display.println(line2);
  display.display();
}

// ========== 播放下一首 ==========
void playNext() {
  showStatus("Loading...");
  MusicItem item = fetchMusicURL();
  if (item.url != "") {
    showStatus("Playing", item.title);
    audio.connecttohost(item.url.c_str());
    isPlaying = true;
  } else {
    showStatus("Failed to load");
  }
}

// ========== 初始化 ==========
void setup() {
  Serial.begin(115200);
  pinMode(BUTTON_PLAY, INPUT_PULLUP);
  pinMode(BUTTON_NEXT, INPUT_PULLUP);

  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected!");

  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("SSD1306 init failed");
    while (true);
  }
  showStatus("WiFi Connected", WiFi.localIP().toString());

  audio.setPinout(I2S_BCLK, I2S_LRC, I2S_DOUT);
  audio.setVolume(10);

  playNext();
}

// ========== 主循環 ==========
unsigned long lastPlayNextTime = 0;

void loop() {
  static bool lastPlayState = HIGH;
  static bool lastNextState = HIGH;

  // 播放/暫停
  bool currentPlay = digitalRead(BUTTON_PLAY);
  if (currentPlay == LOW && lastPlayState == HIGH) {
    if (isPlaying) {
      audio.stopSong();
      showStatus("Paused");
      isPlaying = false;
    } else {
      playNext();
    }
  }
  lastPlayState = currentPlay;

  // 下一首
  bool currentNext = digitalRead(BUTTON_NEXT);
  if (currentNext == LOW && lastNextState == HIGH) {
    playNext();
  }
  lastNextState = currentNext;

  // ? 播放完成 -> 自動下一首（加延時防抖）
  if (!audio.isRunning() && isPlaying) {
    unsigned long now = millis();
    if (now - lastPlayNextTime > 3000) {  // 至少間隔3秒
      playNext();
      lastPlayNextTime = now;
    }
  }

  audio.loop();
  delay(50);
}