Subversion Repositories SmartDukaan

package com.smartdukaan.cron.scheduled;

import nu.pattern.OpenCV;

import org.apache.commons.io.FileUtils;

import org.apache.logging.log4j.LogManager;

import org.apache.logging.log4j.Logger;

import org.opencv.core.Mat;

import org.opencv.core.Size;

import org.opencv.imgcodecs.Imgcodecs;

import org.opencv.imgproc.Imgproc;

import org.json.JSONObject;

import org.openqa.selenium.*;

import org.openqa.selenium.chrome.ChromeDriver;

import org.openqa.selenium.chrome.ChromeOptions;

import org.openqa.selenium.interactions.Actions;

import org.openqa.selenium.support.ui.ExpectedConditions;

import org.openqa.selenium.support.ui.WebDriverWait;

import org.springframework.stereotype.Component;

import javax.imageio.ImageIO;

import java.awt.image.BufferedImage;

import java.io.File;

import java.time.LocalDate;

import java.time.format.DateTimeFormatter;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import java.util.concurrent.TimeUnit;

import java.util.stream.Collectors;

@Component

public class CheckRealmeWarrantyTask {

    private static final Logger LOGGER = LogManager.getLogger(CheckRealmeWarrantyTask.class);

    static {

        try {

            OpenCV.loadShared();

        } catch (Throwable t) {

            LogManager.getLogger(CheckRealmeWarrantyTask.class).warn("OpenCV not available on this platform: {}", t.getMessage());

        }

    }

    public Map<String, LocalDate> checkWarranty(List<String> imeis) {

        Map<String, LocalDate> dateMap = new HashMap<>();

        LOGGER.info("Initiating webdriver...");

        Map<String, Object> prefsMap = new HashMap<>();

        prefsMap.put("profile.default_content_settings.popups", 0);

        prefsMap.put("download.prompt", false);

        prefsMap.put("download.directory_upgrade", true);

        System.setProperty("webdriver.chrome.driver", "/usr/bin/chromedriver");

        //I need this

        //System.setProperty("webdriver.chrome.driver", "/Users/amit/cft/chromedriver/chromedriver");

        ChromeOptions options = new ChromeOptions();

        //options.setBinary("/Users/amit/cft/chrome/Google Chrome for Testing.app/Contents/MacOS/Google Chrome For Testing");

        options.setExperimentalOption("prefs", prefsMap);

        //options.setExperimentalOption("detach", true);

        options.addArguments("--headless");

        options.addArguments("--user-agent=\"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36\"");

        options.addArguments("--no-sandbox");

        options.addArguments("start-maximized");

        options.addArguments("disable-infobars");

        options.addArguments("--disable-extensions");

        options.addArguments("--force-device-scale-factor=1");

        options.addArguments("--test-type");

        options.addArguments(

                "--disable-blink-features=AutomationControlled",

                "--disable-infobars",

                "--disable-popup-blocking",

                "--disable-notifications",

                "--disable-extensions"

        );

        WebDriver driver = null;

        try {

            driver = new ChromeDriver(options);

            driver.manage().timeouts().setScriptTimeout(6, TimeUnit.SECONDS);

            driver.manage().window().setSize(new Dimension(1600, 900));

            driver.manage().window().maximize();

            // Deleting all the cookies

            driver.manage().deleteAllCookies();

            // Specifiying pageLoadTimeout and Implicit wait

            driver.manage().timeouts().pageLoadTimeout(15, TimeUnit.SECONDS);

            driver.manage().timeouts().implicitlyWait(9, TimeUnit.SECONDS);

            int mainCount = 0;

            List<String> remainingImeis = imeis;

            WebDriverWait wait10Sec = new WebDriverWait(driver, 15);

            WebDriverWait wait5Sec = new WebDriverWait(driver, 4);

            WebElement slideButton;

            Actions actionProvider = new Actions(driver);

            do {

                driver.get("https://www.realme.com/in/support/phonecheck");

                installResponseCapture(driver);

            /*try {

                driver.findElement(By.cssSelector(".cp-cookie-tip a.close")).click();

            } catch (Exception e) {

                try {

                    LOGGER.info("Cookie not found");

                } catch (Exception e1) {

                }

            }*/

                for (int i = 0; i < remainingImeis.size(); i++) {

                    String imei = remainingImeis.get(i);

                    try {

                        LOGGER.info("Starting fresh with new IMEI " + imei);

                        // realme rebuilt this page: the field is no longer .sn-input and the

                        // submit is no longer div.check-btn but an icon inside the same box.

                        if (driver.findElement(By.cssSelector(IMEI_INPUT)).getAttribute("value").length() > 0) {

                            //System.out.println("Darn.. leaving" + driver.findElement(By.className("el-input__inner")).getAttribute("value"));

                            driver.get("https://www.realme.com/in/support/phonecheck");

                installResponseCapture(driver);

                            break;

                        }

                        driver.findElement(By.cssSelector(IMEI_INPUT)).sendKeys(imei);

                        //driver.findElement(By.className("el-button--primary")).click();

                        driver.findElement(By.cssSelector(SUBMIT_ICON)).click();

                        // Perform click-and-hold action on the element

                        int counter = 1;

                        boolean captchaNotBroken = true;

                        // release() is only reached on the moveByOffset > 0 path, so an attempt

                        // that fails detection or calibration leaves the button DOWN -- measured

                        // at 77% of realme presses in production. Actions is one instance per

                        // driver, created outside the imei loop, so the stuck press leaks into the

                        // next attempt and the next imei: the following clickAndHold lands on an

                        // already-held button and the widget never repositions the handle.

                        boolean pressed = false;

                        do {

                            String fileName = "/tmp/oppo-simple-i-" + counter + " " + System.currentTimeMillis() + ".png";

                            try {

                                LOGGER.info("Starting Do");

                                //Thread.sleep(5000);

                                wait10Sec.until(ExpectedConditions.visibilityOfElementLocated(By.tagName("canvas")));

                                wait10Sec.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_bg_')]")));

                                wait10Sec.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_wrapper_')]")));

                                wait10Sec.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_slider_')]")));

                                slideButton = driver.findElement(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_slider_')]"));

                                //System.out.println("Slide button - " + slideButton);

                                LOGGER.info("Margin Left before- " + slideButton.getCssValue("margin-left"));

                                actionProvider.moveToElement(slideButton).clickAndHold()

                                        .moveByOffset(1, 0)//.pause(2000)

                                        .perform();

                                pressed = true;

                                //actionProvider.moveByOffset(-1,0).pause(2000).perform();

                                LOGGER.info("Margin Left after - " + slideButton.getCssValue("margin-left"));

                                //Thread.sleep(5000);

                            } catch (Exception e) {

                                LOGGER.info(e.getMessage());

                                driver.get("https://www.realme.com/in/support/phonecheck");

                installResponseCapture(driver);

                                break;

                            }

                            double[] circles = getMatCircles2(driver, fileName);

                            if (circles != null) {

                                double firstCircleX = circles[0];

                                double secondCircleX = circles[1];

                                double distance = Math.abs(firstCircleX - secondCircleX);

                                LOGGER.info("Distance is " + distance);

                                double[] cal = calibrate(driver, actionProvider, distance);

                                int moveByOffset = cal == null ? 0 : (int) cal[0];

                                if (moveByOffset > 0) {

                                    // Move, measure again, close the remainder, THEN release.

                                    actionProvider.moveByOffset(moveByOffset, 0).perform();

                                    refine(driver, actionProvider, cal[1]);

                                    actionProvider.release().perform();

                                    pressed = false;

                                    LOGGER.info("Move click performed (main {}px)", moveByOffset);

                                    try {

                                        // Success used to mean "the dx_captcha_basic_bar-inform error element

                                        // did not appear". realme rebuilt this page, so that element may no

                                        // longer exist -- in which case the wait always times out and EVERY

                                        // attempt reports success while the captcha was never solved. That is

                                        // exactly what happened: 27 successes, 27 missed responses, 0 rows.

                                        //

                                        // The lookup response arriving is the only signal that actually proves

                                        // the captcha passed, so wait for that instead.

                                        String json = awaitResponse(driver, 8000);

                                        if (json == null) {

                                            LOGGER.warn("Failed = {} (captcha said: {}) urls={}",

                                                    counter, captchaSignal(driver), seenUrls(driver));

                                        } else {

                                            LOGGER.info("Success  at attempt " + counter);

                                            //List<WebElement> warrantyDateElements = driver.findElements(By.className("warranty-service--result_info__dateValue"));

                                            //WebElement activationTimeElement = driver.findElement(By.xpath("//*[contains(text(), 'UTC+5.5')  or contains(text(), 'Non-Activate')]"));

                                            // Read the JSON the page already received. The old locator

                                            // keyed off a label that no longer exists, and its "| //h1" branch

                                            // would silently grab a page heading and try to parse it as a date.

                                            // The API is explicit: expiryDate (yyyy.MM.dd) plus an isActivation

                                            // flag, so nothing has to be inferred from message text.

                                            LocalDate activationDate = activationFrom(json);

                                            LOGGER.info("Activation lookup for {} -> {}", imei,

                                                    activationDate != null ? activationDate : "not activated");

                                            // Always record, even with a null date. findElement used to THROW

                                            // when the element was missing, so nothing was written and the imei

                                            // came back on every run indefinitely.

                                            dateMap.put(imei, activationDate);

                                            clearCapture(driver);

                                            if (dateMap.size() == imeis.size()) {

                                                return dateMap;

                                            }

                                            WebElement checkAgainButton = driver.findElement(By.className("recheck-btn"));

                                            captchaNotBroken = false;

                                            checkAgainButton.click();

                                            break;

                                        }

                                    } catch (Throwable e) {

                                        LOGGER.warn("Failed = " + counter + " ----------" + e.getMessage());

                                    }

                                }

                            }

                            // Any path that got here without releasing (null circles, unusable

                            // calibration) must let go before the next attempt re-presses.

                            if (pressed) {

                                try {

                                    actionProvider.release().perform();

                                } catch (Exception releaseFailed) {

                                    LOGGER.warn("Could not release the slider: " + releaseFailed.getMessage());

                                }

                                pressed = false;

                            }

                            LOGGER.info("After circles conditions");

                            wait10Sec.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_wrapper_')]")));

                            wait10Sec.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_slider_')]")));

                            slideButton = driver.findElement(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_slider_')]"));

                            actionProvider.moveToElement(slideButton).doubleClick().perform();

                            LOGGER.info("Ending Do" + counter++);

                        } while (captchaNotBroken && counter <= 20);

                        // The widget-not-found path breaks out mid-iteration; do not carry a held

                        // button into the next imei.

                        if (pressed) {

                            try {

                                actionProvider.release().perform();

                            } catch (Exception releaseFailed) {

                                LOGGER.warn("Could not release the slider: " + releaseFailed.getMessage());

                            }

                        }

                        LOGGER.warn("Counter reached upto 20");

                    } catch (Exception e) {

                        LOGGER.info("Caught unknown - for imei " + imei);

                        LOGGER.error("Realme warranty check failed for imei " + imei, e);

                    }

                    driver.get("https://www.realme.com/in/support/phonecheck");

                installResponseCapture(driver);

                }

                mainCount++;

                remainingImeis = imeis.stream().filter(x -> !dateMap.containsKey(x)).collect(Collectors.toList());

                if (remainingImeis.isEmpty()) break;

            } while (mainCount < 5);

        } finally {

            if (driver != null) {

                try {

                    driver.quit();  // Always shuts everything down

                } catch (Exception e) {

                    LOGGER.warn("Error closing driver: " + e.getMessage());

                }

            }

        }

        return dateMap;

    }

    /** realme rebuilt the page; the old .sn-input / div.check-btn no longer render. */

    private static final String IMEI_INPUT  = ".imei-input input";

    private static final String SUBMIT_ICON = ".imei-input .search-icon";

    /**

     * Calibration nudge, in slider px, sized from the gap rather than fixed.

     *

     * A fixed 15px was far too small: it closed only ~25px, so the ratio came from a

     * measurement ~20% noise and the aim landed ~30px out. A fixed 60px then proved too

     * large in the other direction -- production data showed 85% of attempts with a gap

     * under 60px ended up UNUSABLE (the piece shot past the hole and the measured gap

     * grew), and 45% overall.

     *

     * Aim to close about half the gap: the piece travels roughly ASSUMED_RATIO px per

     * slider px, so nudge ~= gap / (2 * ratio), clamped. The real ratio is still derived

     * from the measurement; this only sizes the probe.

     */

    /*

     * REALME's tuning values, deliberately independent of oppo's -- do not sync the two.

     * Realme currently converts ~60% of completed drags against oppo's ~12% on the same

     * widget, so it is the one that must not be disturbed to chase oppo.

     *

     * Left at 1.7 on purpose. Realme's measured ratio over 1,683 production calibrations

     * is 0.70, so this is wrong here too and the probe is smaller than intended -- but it

     * is wrong while converting 60%, and oppo is carrying the corrected value first. If

     * oppo improves, bring 0.70 over here and measure it on its own.

     */

    private static final double ASSUMED_RATIO = 1.7;

    private static final int MIN_NUDGE = 10;

    private static final int MAX_NUDGE = 60;

    private static final double ALIGNED_PX = 2.0;

    private static int nudgeFor(double gap) {

        int n = (int) Math.round(gap / (2 * ASSUMED_RATIO));

        return Math.max(MIN_NUDGE, Math.min(MAX_NUDGE, n));

    }

    /** Stash the active/check response on window as the page receives it. */

    private void installResponseCapture(WebDriver driver) {

        try {

            ((JavascriptExecutor) driver).executeScript(

                "if (!window.__rmCapInstalled) {"

              + "  window.__rmCapInstalled = true; window.__rmResp = null; window.__rmCaptcha = null; window.__rmSeen = [];"

              // Three transports, because realme's page uses all of them and only the

              // prototype-level patches are reliable.

              //

              // The lookup goes through Nuxt's $fetch (ofetch), which grabs its

              // reference to globalThis.fetch when its bundle is evaluated -- long

              // before driver.get() returns and we can wrap window.fetch. So wrapping

              // window.fetch NEVER sees /active/check: verified on the live page, the

              // same $fetch call is invisible to a window.fetch wrapper and visible to

              // a Response.prototype one. That is why 526 solved captchas produced 0

              // rows: the answer arrived and we could not see it.

              //

              // Response.prototype.json / .text are resolved at call time, so patching

              // them catches any client no matter when it took its fetch reference.

              + "  var O = XMLHttpRequest.prototype.open;"

              + "  XMLHttpRequest.prototype.open = function(m,u){"

              + "    this.addEventListener('load', function(){"

              + "      try { var s=String(u);"

              + "        if (s.indexOf('active/check') !== -1 || s.indexOf('customer-api') !== -1) window.__rmResp = this.responseText;"

              + "        else if (s.indexOf('captcha') !== -1) window.__rmCaptcha = s + ' -> ' + (this.responseText||'').slice(0,200);"

              + "        else if (window.__rmSeen.length < 12) window.__rmSeen.push(s.slice(0,80));"

              + "      } catch(e){}"

              + "    });"

              + "    return O.apply(this, arguments);"

              + "  };"

              + "  var F = window.fetch;"

              + "  if (F) { window.fetch = function(){"

              + "    var u = arguments[0]; u = (u && u.url) ? u.url : String(u);"

              + "    return F.apply(this, arguments).then(function(r){"

              + "      try { if (u.indexOf('active/check') !== -1 || u.indexOf('customer-api') !== -1) { r.clone().text().then(function(t){ window.__rmResp = t; }); }"

              + "        else if (window.__rmSeen.length < 12) window.__rmSeen.push('F ' + u.slice(0,80)); } catch(e){}"

              + "      return r;"

              + "    });"

              + "  }; }"

              // Read the body off the Response itself. Must use the ORIGINAL reader on

              // the clone -- calling the patched one recurses forever (it hangs the page).

              + "  ['json','text'].forEach(function(name){"

              + "    var orig = Response.prototype[name];"

              + "    if (!orig) return;"

              + "    Response.prototype[name] = function(){"

              + "      try { var u = this.url || '';"

              + "        if ((u.indexOf('active/check') !== -1 || u.indexOf('customer-api') !== -1) && !this.__rmSeenBody) {"

              + "          var c = this.clone(); c.__rmSeenBody = 1;"

              + "          orig.call(c).then(function(t){ window.__rmResp = (typeof t === 'string') ? t : JSON.stringify(t); });"

              + "        } else if (u && window.__rmSeen.length < 12 && u.indexOf('captcha') === -1) {"

              + "          window.__rmSeen.push('R ' + u.slice(0,80));"

              + "        } } catch(e){}"

              + "      return orig.apply(this, arguments);"

              + "    };"

              + "  });"

              + "}");

        } catch (Exception e) {

            LOGGER.warn("Could not install the response capture hook: " + e.getMessage());

        }

    }

    /**

     * Wait for the lookup response to arrive, which is the only reliable proof that

     * the captcha was actually solved. Polls rather than blocking so a solved captcha

     * is picked up as soon as the request completes.

     */

    private String awaitResponse(WebDriver driver, long timeoutMs) {

        long deadline = System.currentTimeMillis() + timeoutMs;

        while (System.currentTimeMillis() < deadline) {

            String json = capturedResponse(driver);

            if (json != null && !json.trim().isEmpty()) return json;

            try {

                Thread.sleep(300);

            } catch (InterruptedException ie) {

                Thread.currentThread().interrupt();

                return null;

            }

        }

        return null;

    }

    /** Last response from the captcha widget itself -- says WHY a drag was refused. */

    private String captchaSignal(WebDriver driver) {

        try {

            Object v = ((JavascriptExecutor) driver).executeScript("return window.__rmCaptcha || null;");

            return v == null ? null : v.toString();

        } catch (Exception e) {

            return null;

        }

    }

    /** Non-captcha URLs the page called -- shows what to match on when the lookup is missed. */

    private String seenUrls(WebDriver driver) {

        try {

            Object v = ((JavascriptExecutor) driver).executeScript(

                    "return (window.__rmSeen||[]).join(' | ');");

            return v == null ? "" : v.toString();

        } catch (Exception e) {

            return "";

        }

    }

    private String capturedResponse(WebDriver driver) {

        try {

            Object v = ((JavascriptExecutor) driver).executeScript("return window.__rmResp || null;");

            return v == null ? null : v.toString();

        } catch (Exception e) {

            return null;

        }

    }

    private void clearCapture(WebDriver driver) {

        try {

            ((JavascriptExecutor) driver).executeScript("window.__rmResp = null;");

        } catch (Exception ignored) {

        }

    }

    /**

     * realme returns the WARRANTY EXPIRY, not the activation date, so a year is

     * subtracted -- warranty is 12 months as standard. Verified against our own

     * records: 41,267 of 41,289 stored Realme activation dates precede the date we

     * checked them, averaging 13 days before, which is only consistent with the

     * subtraction being applied. isActivation false means the device is not

     * activated yet and there is no date to derive.

     */

    private LocalDate activationFrom(String json) {

        if (json == null) return null;

        try {

            JSONObject root = new JSONObject(json);

            JSONObject data = root.optJSONObject("data");

            if (data == null) return null;

            if (!data.optBoolean("isActivation", false)) return null;

            String expiry = data.optString("expiryDate", "");

            if (expiry == null || expiry.trim().isEmpty() || "null".equals(expiry)) return null;

            return LocalDate.parse(expiry.trim().split(" ")[0],

                    DateTimeFormatter.ofPattern("yyyy.MM.dd")).minusYears(1);

        } catch (Exception e) {

            LOGGER.warn("Could not read expiryDate from the realme response: " + e.getMessage());

            return null;

        }

    }

    /** @return {sliderPxToMove, sliderPxPerCirclePx}, or null if the circles were unreadable. */

    private double[] calibrate(WebDriver driver, Actions actionProvider, double distance) throws Exception {

        int nudge = nudgeFor(distance);

        actionProvider.moveByOffset(nudge, 0).perform();

        String fileName2 = "/tmp/" + Thread.currentThread().getName() + "-moved.png";

        double[] movedCircles = getMatCircles2(driver, fileName2);

        if (movedCircles == null) return null;

        double movedDistance = Math.abs(movedCircles[0] - movedCircles[1]);

        double closed = distance - movedDistance;

        LOGGER.info("Calibration: gap {} -> {} after {}px, closed {}",

                distance, movedDistance, nudge, closed);

        if (closed <= 0) return null;

        double sliderPerCircle = nudge / closed;

        return new double[]{Math.round(movedDistance * sliderPerCircle), sliderPerCircle};

    }

    /** Measure again after the main move and close the remainder before releasing. */

    private int refine(WebDriver driver, Actions actionProvider, double sliderPerCircle) throws Exception {

        String fileName = "/tmp/" + Thread.currentThread().getName() + "-refine.png";

        double[] circles = getMatCircles2(driver, fileName);

        if (circles == null) return 0;

        double remaining = Math.abs(circles[0] - circles[1]);

        if (remaining <= ALIGNED_PX) return 0;

        int correction = (int) Math.round(remaining * sliderPerCircle);

        if (correction == 0) return 0;

        LOGGER.info("Refine: {}px of gap left -> nudging {}px", remaining, correction);

        actionProvider.moveByOffset(correction, 0).perform();

        return correction;

    }

    private Mat getMatCircles(WebDriver driver, String fileName) throws Exception {

        File screenshot = ((TakesScreenshot) driver).getScreenshotAs(OutputType.FILE);

        BufferedImage fullImg = ImageIO.read(screenshot);

        // Get the location of element on the page

        WebElement imageElement = driver.findElement(By.id("dx_captcha_basic_bg_1"));

        Point point = imageElement.getLocation();

        // Get width and height of the element

        int eleWidth = imageElement.getSize().getWidth();

        int eleHeight = imageElement.getSize().getHeight();

        // Crop the entire page screenshot to get only element screenshot

        BufferedImage eleScreenshot = fullImg.getSubimage(point.getX(), point.getY(),

                eleWidth, eleHeight);

        ImageIO.write(eleScreenshot, "png", screenshot);

        // Copy the element screenshot to disk

        File screenshotLocation = new File(fileName);

        FileUtils.copyFile(screenshot, screenshotLocation);

        Imgcodecs imageCodecs = new Imgcodecs();

        Mat grayMatrix = imageCodecs.imread(fileName, Imgcodecs.IMREAD_COLOR);

        Imgproc.cvtColor(grayMatrix, grayMatrix, Imgproc.COLOR_BGR2GRAY);

        Mat medianBlur = new Mat();

        Imgproc.medianBlur(grayMatrix, medianBlur, 5);

        Mat circles = new Mat();

        Imgproc.HoughCircles(medianBlur, circles, Imgproc.HOUGH_GRADIENT, 1, 15, 50, 20, 17, 25);

        return circles;

    }

    private double[] getMatCircles2(WebDriver driver, String fileName) throws Exception {

        File screenshot = ((TakesScreenshot) driver).getScreenshotAs(OutputType.FILE);

        BufferedImage fullImg = ImageIO.read(screenshot);

        // Get the location of element on the page

        WebElement imageElement = driver.findElement(By.xpath("//*[starts-with(@id, 'dx_captcha_basic_bg_')]"));

        Point point = imageElement.getLocation();

        // Get width and height of the element

        int eleWidth = imageElement.getSize().getWidth();

        int eleHeight = imageElement.getSize().getHeight();

        // Crop the entire page screenshot to get only element screenshot

        BufferedImage eleScreenshot = fullImg.getSubimage(point.getX(), point.getY(),

                eleWidth, eleHeight);

        ImageIO.write(eleScreenshot, "png", screenshot);

        // Copy the element screenshot to disk

        File screenshotLocation = new File(fileName);

        FileUtils.copyFile(screenshot, screenshotLocation);

        Mat src = Imgcodecs.imread(fileName);

        if (src.empty()) {

            LOGGER.warn("Cannot read image: {}", fileName);

            new File(fileName).delete();

            return null;

        }

        Mat gray = new Mat();

        Imgproc.cvtColor(src, gray, Imgproc.COLOR_BGR2GRAY);

        Imgproc.GaussianBlur(gray, gray, new Size(9, 9), 2, 2);

        Mat circles = new Mat();

        Imgproc.HoughCircles(gray, circles, Imgproc.HOUGH_GRADIENT, 1.0,

                20, // min distance between centers

                100, 20, // param1 (Canny high threshold), param2 (accumulator threshold)

                10, 50); // minRadius, maxRadius (adjust as needed)

        if (circles.cols() < 2) {

            new File(fileName).delete();

            return null;

        }

        for (int i = 0; i < circles.cols(); i++) {

            double[] c1 = circles.get(0, i);

            for (int j = i + 1; j < circles.cols(); j++) {

                double[] c2 = circles.get(0, j);

                if (Math.abs(c1[2] - c2[2]) < 3) { // check similar radius

                    new File(fileName).delete();

                    return new double[] {

                            c1[0], c2[0] // x-coordinates

                    };

                }

            }

        }

        new File(fileName).delete();

        return null;

    }

}