#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <NTPClient.h>
#include <WiFiUdp.h>

// WiFi credentials
const char* ssid = "TestESP";
const char* password = "12345678";

// Relay pins
#define LIGHT1 D1
#define LIGHT2 D2

// Default ON/OFF times (HH:MM:SS)
int ON_HOUR = 18, ON_MIN = 0, ON_SEC = 0;
int OFF_HOUR = 6, OFF_MIN = 0, OFF_SEC = 0;

WiFiUDP ntpUDP;
NTPClient timeClient(ntpUDP, "pool.ntp.org", 19800); // +5:30 for IST
ESP8266WebServer server(80);

// Logs
#define MAX_LOGS 20
String logs[MAX_LOGS];
int logIndex = 0;

bool lightsOn = false;
bool manualMode = false;

unsigned long lastCheck = 0;
const unsigned long checkInterval = 1000; // 1 sec

// ===== Utility =====
void addLog(String msg) {
  String logLine = "[" + timeClient.getFormattedTime() + "] " + msg;
  Serial.println(logLine);
  logs[logIndex] = logLine;
  logIndex = (logIndex + 1) % MAX_LOGS;
}

bool isBetweenTimes(int h, int m, int s) {
  int nowSec = h * 3600 + m * 60 + s;
  int onSec  = ON_HOUR * 3600 + ON_MIN * 60 + ON_SEC;
  int offSec = OFF_HOUR * 3600 + OFF_MIN * 60 + OFF_SEC;

  if (onSec < offSec)
    return (nowSec >= onSec && nowSec < offSec);
  else
    return (nowSec >= onSec || nowSec < offSec); // Handles overnight
}

// ===== HTML Page =====
String getHTML() {
  String page = "<html><head><meta http-equiv='refresh' content='3'>";
  page += "<style>body{font-family:monospace;background:#111;color:#0f0;padding:10px;}button{padding:10px;margin:4px;background:#0f0;color:#111;border:none;border-radius:5px;}input{width:50px;text-align:center;background:#000;color:#0f0;border:1px solid #0f0;}</style></head><body>";
  page += "<h2>ESP8266 Smart Light Controller</h2>";
  page += "<p><b>IP:</b> " + WiFi.localIP().toString() + "</p>";
  page += "<p><b>Current Time:</b> " + timeClient.getFormattedTime() + "</p>";
  page += "<p><b>Mode:</b> " + String(manualMode ? "Manual" : "Auto") + "</p>";
  page += "<p><b>Light:</b> " + String(lightsOn ? "ON" : "OFF") + "</p>";
  
  // Manual controls
  page += "<form action='/on'><button>Turn ON</button></form>";
  page += "<form action='/off'><button>Turn OFF</button></form>";
  page += "<form action='/auto'><button>Auto Mode</button></form>";

  // Time settings
  page += "<hr><h3>Change Timer (HH:MM:SS)</h3>";
  page += "<form action='/settime' method='get'>";
  page += "ON <input name='onH' type='number' min='0' max='23' value='" + String(ON_HOUR) + "'> :";
  page += "<input name='onM' type='number' min='0' max='59' value='" + String(ON_MIN) + "'> :";
  page += "<input name='onS' type='number' min='0' max='59' value='" + String(ON_SEC) + "'><br><br>";
  page += "OFF <input name='offH' type='number' min='0' max='23' value='" + String(OFF_HOUR) + "'> :";
  page += "<input name='offM' type='number' min='0' max='59' value='" + String(OFF_MIN) + "'> :";
  page += "<input name='offS' type='number' min='0' max='59' value='" + String(OFF_SEC) + "'><br><br>";
  page += "<button type='submit'>Save Time</button></form><hr>";

  // Logs
  page += "<h3>Logs</h3><div style='max-height:200px;overflow:auto;border:1px solid #333;padding:5px;'>";
  for (int i = 0; i < MAX_LOGS; i++) {
    int idx = (logIndex + i) % MAX_LOGS;
    if (logs[idx].length() > 0) page += logs[idx] + "<br>";
  }
  page += "</div></body></html>";
  return page;
}

// ===== Routes =====
void handleRoot() { server.send(200, "text/html", getHTML()); }

void handleOn() {
  digitalWrite(LIGHT1, LOW);
  digitalWrite(LIGHT2, LOW);
  lightsOn = true;
  manualMode = true;
  addLog("Manual: Lights ON");
  handleRoot();
}

void handleOff() {
  digitalWrite(LIGHT1, HIGH);
  digitalWrite(LIGHT2, HIGH);
  lightsOn = false;
  manualMode = true;
  addLog("Manual: Lights OFF");
  handleRoot();
}

void handleAuto() {
  manualMode = false;
  addLog("Switched to AUTO mode");
  handleRoot();
}

void handleSetTime() {
  if (server.hasArg("onH")) ON_HOUR = server.arg("onH").toInt();
  if (server.hasArg("onM")) ON_MIN  = server.arg("onM").toInt();
  if (server.hasArg("onS")) ON_SEC  = server.arg("onS").toInt();
  if (server.hasArg("offH")) OFF_HOUR = server.arg("offH").toInt();
  if (server.hasArg("offM")) OFF_MIN  = server.arg("offM").toInt();
  if (server.hasArg("offS")) OFF_SEC  = server.arg("offS").toInt();
  
  addLog("Timer set → ON " + String(ON_HOUR) + ":" + String(ON_MIN) + ":" + String(ON_SEC) +
         " / OFF " + String(OFF_HOUR) + ":" + String(OFF_MIN) + ":" + String(OFF_SEC));
  handleRoot();
}

// ===== Setup =====
void setup() {
  Serial.begin(115200);
  pinMode(LIGHT1, OUTPUT);
  pinMode(LIGHT2, OUTPUT);
  digitalWrite(LIGHT1, HIGH);
  digitalWrite(LIGHT2, HIGH);

  WiFi.begin(ssid, password);
  Serial.print("Connecting to WiFi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nConnected! IP: " + WiFi.localIP().toString());

  timeClient.begin();
  timeClient.update();
  addLog("System started and time synced.");

  server.on("/", handleRoot);
  server.on("/on", handleOn);
  server.on("/off", handleOff);
  server.on("/auto", handleAuto);
  server.on("/settime", handleSetTime);
  server.begin();
  addLog("Web server started.");
}

// ===== Loop =====
void loop() {
  server.handleClient();
  unsigned long now = millis();

  if (now - lastCheck >= checkInterval) {
    lastCheck = now;
    timeClient.update();

    if (!manualMode) {
      int h = timeClient.getHours();
      int m = timeClient.getMinutes();
      int s = timeClient.getSeconds();

      bool shouldBeOn = isBetweenTimes(h, m, s);

      if (shouldBeOn && !lightsOn) {
        digitalWrite(LIGHT1, LOW);
        digitalWrite(LIGHT2, LOW);
        lightsOn = true;
        addLog("Auto: Lights ON");
      } 
      else if (!shouldBeOn && lightsOn) {
        digitalWrite(LIGHT1, HIGH);
        digitalWrite(LIGHT2, HIGH);
        lightsOn = false;
        addLog("Auto: Lights OFF");
      }
    }
  }
}