package org.opencv.test.objdetect;

import java.util.List;
import org.opencv.core.Mat;
import org.opencv.core.Size;
import org.opencv.objdetect.QRCodeDetector;
import org.opencv.objdetect.QRCodeEncoder;
import org.opencv.objdetect.QRCodeEncoder_Params;
import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.imgproc.Imgproc;
import org.opencv.test.OpenCVTestCase;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;

public class QRCodeDetectorTest extends OpenCVTestCase {

    private final static String ENV_OPENCV_TEST_DATA_PATH = "OPENCV_TEST_DATA_PATH";
    private String testDataPath;

    @Override
    protected void setUp() throws Exception {
        super.setUp();

        // relys on https://developer.android.com/reference/java/lang/System
        isTestCaseEnabled = System.getProperties().getProperty("java.vm.name") != "Dalvik";

        if (isTestCaseEnabled) {
            testDataPath = System.getenv(ENV_OPENCV_TEST_DATA_PATH);
            if (testDataPath == null)
                throw new Exception(ENV_OPENCV_TEST_DATA_PATH + " has to be defined!");
        }
    }

    public void testDetectAndDecode() {
        Mat img = Imgcodecs.imread(testDataPath + "/cv/qrcode/link_ocv.jpg");
        assertFalse(img.empty());
        QRCodeDetector detector = new QRCodeDetector();
        assertNotNull(detector);
        String output = detector.detectAndDecode(img);
        assertEquals(output, "https://opencv.org/");
    }

    public void testDetectAndDecodeMulti() {
        Mat img = Imgcodecs.imread(testDataPath + "/cv/qrcode/multiple/6_qrcodes.png");
        assertFalse(img.empty());
        QRCodeDetector detector = new QRCodeDetector();
        assertNotNull(detector);
        List < String > output = new ArrayList< String >();
        boolean result = detector.detectAndDecodeMulti(img, output);
        assertTrue(result);
        assertEquals(output.size(), 6);
        List < String > expectedResults = Arrays.asList("SKIP", "EXTRA", "TWO STEPS FORWARD", "STEP BACK", "QUESTION", "STEP FORWARD");
        assertEquals(new HashSet<String>(output), new HashSet<String>(expectedResults));
    }

    public void testKanji() throws UnsupportedEncodingException {
        if (!Charset.isSupported("Shift_JIS"))
            throw new TestSkipException();

        String inp = new String("\u3053\u3093\u306B\u3061\u306F\u4E16\u754C");

        QRCodeEncoder_Params params = new QRCodeEncoder_Params();
        params.set_mode(QRCodeEncoder.MODE_KANJI);
        QRCodeEncoder encoder = QRCodeEncoder.create(params);

        Mat qrcode = new Mat();
        encoder.encode(inp.getBytes("Shift_JIS"), qrcode);
        Imgproc.resize(qrcode, qrcode, new Size(0, 0), 2, 2, Imgproc.INTER_NEAREST);

        QRCodeDetector detector = new QRCodeDetector();
        byte[] output = detector.detectAndDecodeBytes(qrcode);
        assertEquals(detector.getEncoding(), QRCodeEncoder.ECI_SHIFT_JIS);
        assertEquals(inp, new String(output, "Shift_JIS"));

        List < byte[] > outputs = new ArrayList< byte[] >();
        assertTrue(detector.detectAndDecodeBytesMulti(qrcode, outputs));
        assertEquals(detector.getEncoding(0), QRCodeEncoder.ECI_SHIFT_JIS);
        assertEquals(inp, new String(outputs.get(0), "Shift_JIS"));
    }
}