#include <WiFi.h>
#include <HTTPClient.h>
#include <Adafruit_NeoPixel.h>
#include <PubSubClient.h>
#include "driver/rtc_io.h" 

// --- CONFIG ---
const char* WIFI_SSID = "Aussie Broadband ****";
const char* WIFI_PASS = "Ffdfmu****";
// N8N HTTP IP
const char* N8N_URL   = "http://192.168.20.13:5678/webhook/front-door-cam";

// MQTT
const char* MQTT_BROKER = "192.168.20.30";
const int   MQTT_PORT   = 1883;
const char* MQTT_USER   = "mqtt-user";
const char* MQTT_PASS   = "sam***";
const char* MQTT_TOPIC  = "front-door-cam/events";

// --- TIMING ---
const long TIME_SLEEP_BUTTON = 120000; 
const long TIME_SLEEP_PIR    = 60000;
const long TIME_RETRIGGER    = 10000;

// --- PINS ---
#define PIN_BTN      14
#define PIN_PIR      13
#define PIN_LED      12
#define PIN_RX_CAM   18
#define PIN_TX_CAM   17

Adafruit_NeoPixel strip(12, PIN_LED, NEO_GRB + NEO_KHZ800);
HardwareSerial CamSerial(1);
WiFiClient espClient;
PubSubClient mqtt(espClient);

// Colors
uint32_t C_RED    = strip.Color(255, 0, 0);
uint32_t C_BLUE   = strip.Color(0, 0, 255);
uint32_t C_YELLOW = strip.Color(255, 200, 0);
uint32_t C_GREEN  = strip.Color(0, 255, 0);
uint32_t C_OFF    = 0;

void setColor(uint32_t c) { strip.fill(c); strip.show(); }

void setup() {
  Serial.begin(115200);
  
  CamSerial.begin(115200, SERIAL_8N1, PIN_RX_CAM, PIN_TX_CAM);
  pinMode(PIN_BTN, INPUT_PULLUP);
  pinMode(PIN_PIR, INPUT_PULLDOWN);
  strip.begin(); strip.setBrightness(50);

  Serial.println("Connecting WiFi...");
  WiFi.setTxPower(WIFI_POWER_19_5dBm);
  WiFi.begin(WIFI_SSID, WIFI_PASS);
  
  int t=0;
  while(WiFi.status() != WL_CONNECTED && t < 16) { delay(500); t++; }
  if(WiFi.status() == WL_CONNECTED) Serial.println("Connected.");
  else Serial.println("WiFi Failed.");

  // Check Wakeup
  esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
  bool btnPressed = (digitalRead(PIN_BTN) == LOW);
  bool pirTrigger = (digitalRead(PIN_PIR) == HIGH);

  if (cause == ESP_SLEEP_WAKEUP_EXT0 || btnPressed) {
    handleTrigger("BUTTON");
  } 
  else if (cause == ESP_SLEEP_WAKEUP_EXT1 || pirTrigger) {
    handleTrigger("MOTION");
  } 
  else {
    Serial.println("Fresh Boot.");
    setColor(C_GREEN); delay(2000);
    goToSleep();
  }
}

void loop() {
  // Main loop handles Retrigger logic
  if (digitalRead(PIN_BTN) == LOW) {
    // Only re-trigger if logic is running
    handleTrigger("BUTTON"); 
  }
  // If we fall through here, go to sleep
  goToSleep();
}

// Main Logic Sequence
void handleTrigger(const char* type) {
  Serial.printf("TRIGGER: %s\n", type);
  
  // 1. Set Visual State
  uint32_t stateColor = (strcmp(type, "BUTTON") == 0) ? C_BLUE : C_RED;
  int maxAwakeTime = (strcmp(type, "BUTTON") == 0) ? TIME_SLEEP_BUTTON : TIME_SLEEP_PIR;
  
  setColor(stateColor);

  // 2. Send MQTT IMMEDIATELY (Before Image)
  if (WiFi.status() == WL_CONNECTED) {
    sendMQTT(type);
  }

  // 3. Wait 2s Pre-Snap
  delay(2000);

  // 4. Snap & Upload N8N
  if (WiFi.status() == WL_CONNECTED) {
    snapAndUploadN8N(type);
  }
  
  // Restore Color
  setColor(stateColor);

  // 5. Cooldown Loop (Stay Awake)
  unsigned long startLoop = millis();
  while (millis() - startLoop < maxAwakeTime) {
    
    // Check for BUTTON Retrigger
    if (digitalRead(PIN_BTN) == LOW) {
      // Debounce Check
      static unsigned long lastBtnTime = 0;
      if (millis() - lastBtnTime > TIME_RETRIGGER) {
        Serial.println("Retriggered by Button!");
        lastBtnTime = millis();
        // Reset timers and switch to Button Mode
        type = "BUTTON";
        stateColor = C_BLUE;
        maxAwakeTime = TIME_SLEEP_BUTTON;
        setColor(C_BLUE);
        startLoop = millis(); // Reset Sleep Timer
        
        // REPEAT ACTION
        sendMQTT("BUTTON");
        delay(2000);
        snapAndUploadN8N("BUTTON");
        setColor(C_BLUE);
      }
    }
    delay(100);
  }

  goToSleep();
}

void sendMQTT(const char* eventType) {
  mqtt.setServer(MQTT_BROKER, MQTT_PORT);
  if (mqtt.connect("ESP32Doorbell", MQTT_USER, MQTT_PASS)) {
    char payload[64];
    // Simple Alert Payload
    snprintf(payload, sizeof(payload), "{\"event\": \"%s\", \"status\": \"active\"}", eventType);
    mqtt.publish(MQTT_TOPIC, payload);
    mqtt.disconnect();
    Serial.println("MQTT Sent.");
  } else {
    Serial.println("MQTT Failed.");
  }
}

void snapAndUploadN8N(const char* eventName) {
  setColor(C_YELLOW); 

  while(CamSerial.available()) CamSerial.read();
  CamSerial.write('S');

  uint32_t start = millis();
  while (CamSerial.available() < 4) {
    if (millis() - start > 3000) {
      Serial.println("Camera Timeout");
      return;
    }
  }

  uint32_t imgLen = 0;
  CamSerial.readBytes((char*)&imgLen, 4);
  Serial.printf("Size: %d\n", imgLen);
  
  if (imgLen > 300000) return;

  uint8_t *fb = (uint8_t *)malloc(imgLen);
  if (!fb) return;

  uint32_t received = 0;
  start = millis();
  while (received < imgLen && (millis() - start < 5000)) {
    if (CamSerial.available()) fb[received++] = CamSerial.read();
  }

  if (received == imgLen) {
    HTTPClient http;
    if (http.begin(N8N_URL)) {
      http.addHeader("Content-Type", "image/jpeg");
      http.addHeader("X-Event-Type", eventName);
      
      int code = http.POST(fb, imgLen);
      Serial.printf("N8N Upload: %d\n", code);
      http.end();
    }
  }
  free(fb);
}

void goToSleep() {
  Serial.println("Sleep.");
  setColor(C_OFF);
  delay(100); 

  rtc_gpio_pullup_en((gpio_num_t)PIN_BTN);
  rtc_gpio_pulldown_dis((gpio_num_t)PIN_BTN);
  
  esp_sleep_enable_ext0_wakeup((gpio_num_t)PIN_BTN, 0); 
  esp_sleep_enable_ext1_wakeup(1ULL << PIN_PIR, ESP_EXT1_WAKEUP_ANY_HIGH); 
  
  esp_deep_sleep_start();
}