<?php
// temperature_handler.php - Podrška za CLI i HTTP
date_default_timezone_set('Europe/Belgrade');

error_reporting(E_ALL);
ini_set('display_errors', 1);
ini_set('log_errors', 1);
ini_set('error_log', '/tmp/php_debug.log');

// DEBUG: Loguj početak izvršavanja
file_put_contents('/tmp/debug.log', "=== SCRIPT STARTED ===\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Time: " . date('Y-m-d H:i:s') . "\n", FILE_APPEND);

// DODAJTE OVE LINIJE - pratimo tok izvršavanja
file_put_contents('/tmp/debug.log', "1. Before includes\n", FILE_APPEND);

// ================= KONFIGURACIJA =================
define('API_KEY', 'esp32-secure-key-2024');

// ================= DETEKCIJA OKRUŽENJA =================
$isCli = (php_sapi_name() === 'cli');

// ================= KONFIGURACIJA =================
define('API_KEY', 'esp32-secure-key-2024');
define('LOW_TEMP_THRESHOLD', 18.0);
define('HIGH_TEMP_THRESHOLD', 25.0);
define('HYSTERESIS', 1.0);
define('LOG_FILE', __DIR__ . '/temperature.log');

// Dozvoljeni sensor IDs
$allowedSensors = ['esp32-bme280-01', 'esp32-bme280-02'];

// ================= INICIJALIZACIJA ZA HTTP =================
if (!$isCli) {
    header('Content-Type: application/json; charset=utf-8');
    header('Access-Control-Allow-Origin: *');
    header('Access-Control-Allow-Methods: POST, OPTIONS');
    header('Access-Control-Allow-Headers: Content-Type, X-API-Key');
}

// ================= FUNKCIJE =================
function logEvent($level, $message) {
    $logEntry = sprintf(
        "[%s] [%s] %s\n",
        date('Y-m-d H:i:s'),
        $level,
        $message
    );

    @file_put_contents(LOG_FILE, $logEntry, FILE_APPEND | LOCK_EX);
}

function sendJsonError($message, $code = 500) {
    global $isCli;

    if (!$isCli) {
        http_response_code($code);
    }

    echo json_encode([
        'status' => 'error',
        'message' => $message,
        'timestamp' => date('Y-m-d H:i:s')
    ], JSON_UNESCAPED_UNICODE);

    if ($isCli) {
        echo "\n"; // Dodaj novi red za CLI
    }

    exit;
}

// ================= OBRADA ZA CLI =================
if ($isCli) {
    // Proveri da li su prosleđeni argumenti
    if ($argc > 1 && $argv[1] === 'test') {
        $testData = '{"temperature": 22.5, "sensor_id": "test-sensor", "humidity": 45.0, "pressure": 1013.25}';
        processRequest($testData, true);
    } else {
        echo "Usage: php temperature_handler.php test\n";
        echo "Or pipe JSON data: echo '{\"temperature\":22.5}' | php temperature_handler.php\n";
        exit;
    }
} else {
    // ================= OBRADA ZA HTTP =================
    // Obradi OPTIONS zahtev za CORS
    if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
        http_response_code(200);
        exit;
    }

    // Provera HTTP metode
    if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
        sendJsonError('Samo POST zahtevi su dozvoljeni', 405);
    }

    // Autentifikacija za HTTP
    $apiKey = $_SERVER['HTTP_X_API_KEY'] ?? '';
    if (empty($apiKey)) {
        sendJsonError('API ključ je obavezan', 401);
    }

    if ($apiKey !== API_KEY) {
        sendJsonError('Nevažeći API ključ', 401);
    }

  // Provera Content-Type
    $contentType = $_SERVER['CONTENT_TYPE'] ?? '';
    if (stripos($contentType, 'application/json') === false) {
        sendJsonError('Unsupported Media Type', 415);
    }

    // Čitanje JSON podataka
    $json = file_get_contents('php://input');
    processRequest($json, false);
}

// ================= GLAVNA FUNKCIJA ZA OBRADU =================
function processRequest($json, $isTest = false) {
    global $allowedSensors;

    logEvent('DEBUG', 'ProcessRequest started');
file_put_contents('/tmp/debug.log', "5. processRequest started\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Raw input: " . file_get_contents('php://input') . "\n", FILE_APPEND);
    file_put_contents('/tmp/debug.log', "JSON var: " . $json . "\n", FILE_APPEND);

    // Debug HTTP headers
file_put_contents('/tmp/debug.log', "Content-Type: " . ($_SERVER['CONTENT_TYPE'] ?? 'NOT SET') . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Request Method: " . ($_SERVER['REQUEST_METHOD'] ?? 'NOT SET') . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "JSON length: " . strlen($json) . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "JSON content: '" . $json . "'\n", FILE_APPEND);

    if (strlen($json) === 0) {
file_put_contents('/tmp/debug.log', "JSON is REALLY empty\n", FILE_APPEND);
        sendJsonError('JSON podaci su prazni', 400);
    } else {
file_put_contents('/tmp/debug.log', "JSON has data, continuing ...\n", FILE_APPEND);
    }
file_put_contents('/tmp/debug.log', "8. Before json_decode\n", FILE_APPEND);

    $data = json_decode($json, true);
    if (json_last_error() !== JSON_ERROR_NONE) {
file_put_contents('/tmp/debug.log', "10. JSON decode error: " . json_last_error_msg() . "\n", FILE_APPEND);
        sendJsonError('Nevažeći JSON format: ' . json_last_error_msg(), 400);
    }
file_put_contents('/tmp/debug.log', "11. JSON decoded successfully\n", FILE_APPEND);

    // Validacija obaveznih polja
file_put_contents('/tmp/debug.log', "12. Before validation - data: " . print_r($data, true) . "\n", FILE_APPEND);
// Proverite tačno šta se dešava u validaciji
$tempExists = isset($data['temperature']);
$sensorExists = isset($data['sensor_id']);

file_put_contents('/tmp/debug.log', "Temperature exists: " . ($tempExists ? 'YES' : 'NO') . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Sensor_id exists: " . ($sensorExists ? 'YES' : 'NO') . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Temperature value: " . ($data['temperature'] ?? 'NULL') . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Sensor_id value: " . ($data['sensor_id'] ?? 'NULL') . "\n", FILE_APPEND);

    if (!isset($data['temperature']) || !isset($data['sensor_id'])) {
file_put_contents('/tmp/debug.log', "13. Validation failed\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Temperature exists: " . (isset($data['temperature']) ? 'YES' : 'NO') . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "Sensor_id exists: " . (isset($data['sensor_id']) ? 'YES' : 'NO') . "\n", FILE_APPEND);
        sendJsonError('Nedostaje temperatura ili sensor_id', 400);
    }
file_put_contents('/tmp/debug.log', "14. Validation passed - extracting values\n", FILE_APPEND);
    $sensorId = trim($data['sensor_id']);
    $temperature = floatval($data['temperature']);
    $humidity = isset($data['humidity']) ? floatval($data['humidity']) : null;
    $pressure = isset($data['pressure']) ? floatval($data['pressure']) : null;
file_put_contents('/tmp/debug.log', "15. Extracted - Sensor: '$sensorId', Temp: $temperature, Humidity: " . ($humidity ?? 'NULL') . ", Pressure: " . ($pressure ?? 'NULL') . "\n", FILE_APPEND);

// Provera dozvoljenih senzora
file_put_contents('/tmp/debug.log', "16. Checking allowed sensors\n", FILE_APPEND);
    $allowedSensors = ['esp32-bme280-01', 'esp32-bme280-02'];
    $isAllowed = in_array($sensorId, $allowedSensors);

    if (!$isAllowed) {
file_put_contents('/tmp/debug.log', "18. Sensor not allowed error\n", FILE_APPEND);
        sendJsonError('Nedozvoljeni sensor ID: ' . $sensorId, 403);
}

    // Za test mode, preskoči proveru senzora
    if (!$isTest && !in_array($sensorId, $allowedSensors)) {
        sendJsonError('Nedozvoljeni sensor ID: ' . $sensorId, 403);
    }
    // Validacija temperature
    if ($temperature < -50 || $temperature > 100) {
        sendJsonError('Temperatura van opsega (-50 do 100)', 400);
    }
    // ================= LOGIKA ZA GREJANJE =================
    $lastHeatingState = 'off'; // Početno stanje
    $isCurrentlyHeating = ($lastHeatingState === 'on');

file_put_contents('/tmp/debug.log', "19. Sensor allowed, continuing...\n", FILE_APPEND);

// Konekcija sa bazom
file_put_contents('/tmp/debug.log', "20. Before database connection\n", FILE_APPEND);
	$pdo = getDatabaseConnection();
file_put_contents('/tmp/debug.log', "21. After database connection\n", FILE_APPEND);

// Logika za grejanje
file_put_contents('/tmp/debug.log', "22. Before heating logic\n", FILE_APPEND);
	$lastHeatingState = getLastHeatingState($pdo, $sensorId);
	$isCurrentlyHeating = ($lastHeatingState === 'on');
	$heatingCommand = determineHeatingCommand($temperature, $isCurrentlyHeating);

file_put_contents('/tmp/debug.log', "23. Heating command: $heatingCommand (last state: $lastHeatingState, current temp: $temperature)\n", FILE_APPEND);

// Snimanje u bazu
file_put_contents('/tmp/debug.log', "24. Before database insert\n", FILE_APPEND);
	$insertId = saveTemperatureData($pdo, $sensorId, $temperature, $humidity, $pressure, $heatingCommand);
file_put_contents('/tmp/debug.log', "25. After database insert, ID: " . ($insertId ?: 'FAILED') . "\n", FILE_APPEND);

    // Određivanje komande sa histerezom
    	$heatingCommand = determineHeatingCommand($temperature, $isCurrentlyHeating);

    // Snimanje podataka (simulacija za sada)
//    saveTemperatureData($sensorId, $temperature, $humidity, $pressure, $heatingCommand);

    // ================= GENERISANJE ODGOVORA =================
    $response = [
        'status' => 'success',
        'received_data' => [
            'temperature' => $temperature,
            'humidity' => $humidity,
            'pressure' => $pressure,
            'sensor_id' => $sensorId,
            'timestamp' => date('Y-m-d H:i:s')
        ],
        'heating_command' => $heatingCommand,
        'message' => getHeatingMessage($heatingCommand, $temperature),
        'threshold_info' => [
            'low_threshold' => LOW_TEMP_THRESHOLD,
            'high_threshold' => HIGH_TEMP_THRESHOLD,
            'hysteresis' => HYSTERESIS,
            'current_temperature' => $temperature
        ]
    ];
    
    if (!$isTest) {
        http_response_code(200);
    }
    
    echo json_encode($response, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
    
    if ($isTest) {
        echo "\n"; // Dodaj novi red za CLI
    }
    
    logEvent('INFO', "Uspeh - Sensor $sensorId: Temp={$temperature}°C, Cmd=$heatingCommand");
}

// ================= POMOĆNE FUNKCIJE =================
function determineHeatingCommand($temperature, $isCurrentlyHeating) {
    if ($isCurrentlyHeating) {
        return ($temperature > (HIGH_TEMP_THRESHOLD + HYSTERESIS)) ? 'off' : 'on';
    } else {
        return ($temperature < (LOW_TEMP_THRESHOLD - HYSTERESIS)) ? 'on' : 'off';
    }
}

function getHeatingMessage($command, $temperature) {
    if ($command === 'on') {
        return "Grejanje UKLJUČENO. Temperatura (" . $temperature . "°C) je ispod donjeg praga.";
    } else {
        return "Grejanje ISKLJUČENO. Temperatura (" . $temperature . "°C) je iznad gornjeg praga.";
    }
}


function saveTemperatureData($sensorId, $temperature, $humidity, $pressure, $command) {
    $logEntry = sprintf(
        "[%s] Sensor: %s, Temp: %.1f°C, Humidity: %.1f%%, Pressure: %.1fhPa, Command: %s\n",
        date('Y-m-d H:i:s'),
        $sensorId,
        $temperature,
        $humidity ?? 0,
        $pressure ?? 0,
        $command
    );

    @file_put_contents(LOG_FILE, $logEntry, FILE_APPEND | LOCK_EX);
}
function getDatabaseConnection() {
// Dodajte ove linije u getDatabaseConnection()
file_put_contents('/tmp/debug.log', "PHP_SAPI: " . PHP_SAPI . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "PHP_VERSION: " . PHP_VERSION . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "PDO_DRIVERS: " . implode(', ', PDO::getAvailableDrivers()) . "\n", FILE_APPEND);
    try {
file_put_contents('/tmp/debug.log', "DB_CONNECTION: Attempting to connect...\n", FILE_APPEND);
        $dsn = "mysql:host=" . DB_HOST . ";dbname=" . DB_NAME . ";charset=" . DB_CHARSET;
file_put_contents('/tmp/debug.log', "DB_CONNECTION: DSN: $dsn\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "DB_CONNECTION: User: " . DB_USER . "\n", FILE_APPEND);
// Dodajte timeout za PDO konekciju
        $options = [
            PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
            PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
            PDO::ATTR_EMULATE_PREPARES => false,
            PDO::ATTR_TIMEOUT => 5, // 5 sekundi timeout
        ];
file_put_contents('/tmp/debug.log', "DB_CONNECTION: Creating PDO instance...\n", FILE_APPEND);
        $pdo = new PDO($dsn, DB_USER, DB_PASS, [
            PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
            PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
            PDO::ATTR_EMULATE_PREPARES => false,
        ]);
file_put_contents('/tmp/debug.log', "DB_CONNECTION: Successfully connected!\n", FILE_APPEND);
        logEvent('INFO', 'Uspešna konekcija sa bazom podataka');
        return $pdo;

    } catch (PDOException $e) {
file_put_contents('/tmp/debug.log', "DB_CONNECTION_ERROR: " . $e->getMessage() . "\n", FILE_APPEND);
file_put_contents('/tmp/debug.log', "DB_CONNECTION_ERROR_CODE: " . $e->getCode() . "\n", FILE_APPEND);
        logEvent('ERROR', 'Greška pri konekciji sa bazom: ' . $e->getMessage());
        // DODAJTE OVO ZA DEBUG:
        error_log("PDO ERROR: " . $e->getMessage());
        sendJsonError('Database connection failed: ' . $e->getMessage(), 500);
    } catch (Exception $e) {
        file_put_contents('/tmp/debug.log', "GENERAL_DB_ERROR: " . $e->getMessage() . "\n", FILE_APPEND);
	sendJsonError('Database error: ' . $e->getMessage(), 500);
    }
}
?>