/*
 * ESP32 智慧溫室整合系統 (IoT Smart Greenhouse) - 無庫版 Servo
 * 平台：Wokwi Simulator
 * 修正：移除 ESP32Servo 依賴，改用 ledc 底層控制
 */

#include <WiFi.h>
#include <WebServer.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHTesp.h>

// ================= 定義引腳 (Pin Definitions) =================

#define DHT_PIN 15
#define TRIG_PIN 5
#define ECHO_PIN 18
#define STEP_PIN 19
#define DIR_PIN  23
#define SERVO_PIN 4      // 伺服馬達
#define SOIL_PIN 34
#define RELAY_PIN 13

// LED Bar 引腳
const int ledPins[8] = {32, 33, 25, 26, 27, 14, 12, 2}; 

// ================= 參數設置 (Settings) =================

const char* ssid = "Wokwi-GUEST";
const char* password = "";

const float TEMP_THRESHOLD_FAN = 30.0;
const int STEP_SPEED = 2000; // 步進馬達速度 (us)

// Servo PWM 設置 (模擬 Servo 庫)
const int servoChannel = 0; // 使用 PWM 通道 0
const int servoFreq = 50;   // Servo 需要 50Hz
const int servoRes = 16;    // 16-bit 解析度 (0-65535)

// ================= 全局物件與變數 =================

DHTesp dht;
LiquidCrystal_I2C lcd(0x27, 16, 2);
WebServer server(80);

// 數據變數
float humidity = 0;
float temperature = 0;
float waterDistance = 0;
float waterLevelPercent = 0;
int soilMoisturePercent = 0;

// 狀態變數
bool fanManualOverride = false;
bool fanState = false;
bool pumpState = false;
bool wateringState = false;

// 計時器
unsigned long lastSensorTime = 0;
unsigned long lastLcdTime = 0;
unsigned long lastSerialTime = 0;
unsigned long lastStepTime = 0;

// ================= 函數聲明 =================

void setupWifi();
void handleRoot();
void handleFanOn();
void handleFanOff();
void setServoAngle(int angle); // 手動控制 Servo 的函數
void readSensors();
void updateOutputs();
void updateLCD();
void printASCIIStatus();

// ================= Setup =================

void setup() {
  Serial.begin(115200);
  
  // 初始化引腳
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(STEP_PIN, OUTPUT);
  pinMode(DIR_PIN, OUTPUT);
  pinMode(RELAY_PIN, OUTPUT);
  pinMode(SOIL_PIN, INPUT);
  
  for(int i=0; i<8; i++) pinMode(ledPins[i], OUTPUT);

  // 初始化 Servo (使用 LEDC PWM)
  ledcAttach(SERVO_PIN, servoFreq, servoRes); // Wokwi 支援的新版語法，或舊版 ledcSetup
  setServoAngle(0); // 初始關閉

  // 初始化組件
  dht.setup(DHT_PIN, DHTesp::DHT22);
  lcd.init();
  lcd.backlight();
  
  setupWifi();
}

// ================= Loop =================

void loop() {
  server.handleClient();
  unsigned long currentMillis = millis();

  // 1. 讀取傳感器 (1秒一次)
  if (currentMillis - lastSensorTime >= 1000) {
    lastSensorTime = currentMillis;
    readSensors();
    updateOutputs();
  }

  // 2. 更新 LCD (1秒一次)
  if (currentMillis - lastLcdTime >= 1000) {
    lastLcdTime = currentMillis;
    updateLCD();
  }

  // 3. 串口圖形化輸出 (3秒一次)
  if (currentMillis - lastSerialTime >= 3000) {
    lastSerialTime = currentMillis;
    printASCIIStatus();
  }

  // 4. 步進馬達 (無阻塞運作)
  bool fanShouldRun = (temperature > TEMP_THRESHOLD_FAN) || fanManualOverride;
  if (fanShouldRun) {
    fanState = true;
    if (micros() - lastStepTime >= STEP_SPEED) {
      lastStepTime = micros();
      digitalWrite(STEP_PIN, !digitalRead(STEP_PIN));
    }
  } else {
    fanState = false;
  }
}

// ================= 自定義 Servo 函數 (核心修改) =================

// 將角度 (0-180) 轉換為 PWM 佔空比
// Servo 0度 ≈ 0.5ms, 180度 ≈ 2.5ms, 週期 20ms
// 16-bit 解析度: 0-65535
void setServoAngle(int angle) {
  // 限制角度範圍
  if (angle < 0) angle = 0;
  if (angle > 180) angle = 180;

  // 計算脈寬 (0.5ms ~ 2.5ms)
  // 映射角度 0-180 到 脈寬 500-2500 微秒
  long pulseWidthUs = map(angle, 0, 180, 500, 2500);
  
  // 計算佔空比數值 (Duty Cycle)
  // 佔空比 = (脈寬 / 週期20000us) * 65536
  long duty = (pulseWidthUs * 65536) / 20000;

  ledcWrite(SERVO_PIN, duty);
}

// ================= 邏輯處理 =================

void readSensors() {
  TempAndHumidity data = dht.getTempAndHumidity();
  if (!isnan(data.temperature)) {
    temperature = data.temperature;
    humidity = data.humidity;
  }

  digitalWrite(TRIG_PIN, LOW); delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH); delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  long duration = pulseIn(ECHO_PIN, HIGH, 30000);
  waterDistance = duration * 0.034 / 2;
  if (waterDistance == 0) waterDistance = 30; // 避免除錯或超時顯示0

  waterLevelPercent = map(waterDistance, 20, 2, 0, 100); 
  waterLevelPercent = constrain(waterLevelPercent, 0, 100);

  int rawSoil = analogRead(SOIL_PIN);
  soilMoisturePercent = map(rawSoil, 0, 4095, 0, 100); 
}

void updateOutputs() {
  // LED Bar
  int ledLevel = map(temperature, 0, 50, 0, 8);
  for (int i = 0; i < 8; i++) {
    digitalWrite(ledPins[i], (i < ledLevel) ? HIGH : LOW);
  }

  // 補水 Pump
  if (waterDistance > 18.0) {
    digitalWrite(RELAY_PIN, HIGH);
    pumpState = true;
  } else if (waterDistance < 5.0) {
    digitalWrite(RELAY_PIN, LOW);
    pumpState = false;
  }

  // 澆水 Servo (自動控制)
  // 如果土壤乾且水箱有水
  if (soilMoisturePercent < 30 && waterDistance < 15.0) {
    if (!wateringState) {
       setServoAngle(90); // 打開閥門
       wateringState = true;
    }
  } else {
    if (wateringState) {
       setServoAngle(0);  // 關閉閥門
       wateringState = false;
    }
  }
}

void updateLCD() {
  lcd.setCursor(0, 0);
  lcd.printf("T:%.1f H:%.0f%%", temperature, humidity);
  lcd.setCursor(0, 1);
  String fStatus = fanState ? "ON" : "OF";
  lcd.printf("Lvl:%02.0f%% Fan:%s", waterLevelPercent, fStatus);
}

void printASCIIStatus() {
  Serial.println("================ SYSTEM STATUS ================");
  Serial.print("Web Control IP: "); Serial.println(WiFi.localIP());
  
  Serial.print("Temp ["); Serial.print(temperature, 1); Serial.print("C]: ");
  int tBars = map(temperature, 0, 50, 0, 20);
  for(int i=0; i<20; i++) Serial.print(i < tBars ? "#" : ".");
  Serial.println();

  Serial.print("Soil ["); Serial.print(soilMoisturePercent); Serial.print("%]: ");
  int sBars = map(soilMoisturePercent, 0, 100, 0, 20);
  for(int i=0; i<20; i++) Serial.print(i < sBars ? "=" : ".");
  Serial.println();

  Serial.printf("Status: FAN[%s]  PUMP[%s]  VALVE[%s]\n", 
    fanState ? "RUN" : "OFF", pumpState ? "ON " : "OFF", wateringState ? "OPEN" : "CLOS");
  Serial.println("===============================================\n");
}

void setupWifi() {
  Serial.print("Connecting Wifi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500); Serial.print(".");
  }
  Serial.println(" OK!");
  server.on("/", handleRoot);
  server.on("/fan/on", handleFanOn);
  server.on("/fan/off", handleFanOff);
  server.begin();
}

void handleRoot() {
  String html = "<html><body style='font-family:sans-serif; text-align:center; padding:50px;'>";
  html += "<h1>ESP32 Greenhouse</h1>";
  html += "<h2>Temp: " + String(temperature) + " C | Hum: " + String(humidity) + " %</h2>";
  html += "<p>Water Level: " + String(waterLevelPercent) + "%</p>";
  html += "<p><a href='/fan/on'><button style='font-size:20px;padding:10px;background:green;color:white;'>Fan ON</button></a>";
  html += "&nbsp;<a href='/fan/off'><button style='font-size:20px;padding:10px;background:red;color:white;'>Fan Auto</button></a></p>";
  html += "</body></html>";
  server.send(200, "text/html", html);
}

void handleFanOn() { fanManualOverride = true; server.sendHeader("Location", "/"); server.send(303); }
void handleFanOff() { fanManualOverride = false; server.sendHeader("Location", "/"); server.send(303); }