// This file is part of OpenCV project.
// It is subject to the license terms in the LICENSE file found in the top-level directory
// of this distribution and at http://opencv.org/license.html

#include "test_precomp.hpp"

namespace opencv_test { namespace {

TEST(Features2d_AKAZE, detect_and_compute_split)
{
    Mat testImg(100, 100, CV_8U);
    theRNG().fill(testImg, RNG::UNIFORM, Scalar(0), Scalar(255), true);

    Ptr<Feature2D> ext = AKAZE::create(AKAZE::DESCRIPTOR_MLDB, 0, 3, 0.001f, 1, 1, KAZE::DIFF_PM_G2);
    vector<KeyPoint> detAndCompKps;
    Mat desc;
    ext->detectAndCompute(testImg, noArray(), detAndCompKps, desc);

    vector<KeyPoint> detKps;
    ext->detect(testImg, detKps);

    ASSERT_EQ(detKps.size(), detAndCompKps.size());

    for(size_t i = 0; i < detKps.size(); i++)
        ASSERT_EQ(detKps[i].hash(), detAndCompKps[i].hash());
}

/**
 * This test is here to guard propagation of NaNs that happens on this image. NaNs are guarded
 * by debug asserts in AKAZE, which should fire for you if you are lucky.
 *
 * This test also reveals problems with uninitialized memory that happens only on this image.
 * This is very hard to hit and depends a lot on particular allocator. Run this test in valgrind and check
 * for uninitialized values if you think you are hitting this problem again.
 */
TEST(Features2d_AKAZE, uninitialized_and_nans)
{
    Mat b1 = imread(cvtest::TS::ptr()->get_data_path() + "../stitching/b1.png");
    ASSERT_FALSE(b1.empty());

    vector<KeyPoint> keypoints;
    Mat desc;
    Ptr<Feature2D> akaze = AKAZE::create();
    akaze->detectAndCompute(b1, noArray(), keypoints, desc);
}

// Test for https://github.com/opencv/opencv/issues/27134
TEST(Features2d_KAZE, diffusivity_charbonnier)
{
    Mat testImg(200, 200, CV_8U);
    theRNG().fill(testImg, RNG::UNIFORM, Scalar(0), Scalar(255), true);

    // KAZE with DIFF_CHARBONNIER
    Ptr<KAZE> kaze_charbonnier = KAZE::create(false, false, 0.001f, 4, 4, KAZE::DIFF_CHARBONNIER);
    vector<KeyPoint> kps_charbonnier;
    Mat desc_charbonnier;
    kaze_charbonnier->detectAndCompute(testImg, noArray(), kps_charbonnier, desc_charbonnier);

    // KAZE with DIFF_PM_G2 (default)
    Ptr<KAZE> kaze_pm_g2 = KAZE::create(false, false, 0.001f, 4, 4, KAZE::DIFF_PM_G2);
    vector<KeyPoint> kps_pm_g2;
    Mat desc_pm_g2;
    kaze_pm_g2->detectAndCompute(testImg, noArray(), kps_pm_g2, desc_pm_g2);

    // Both should detect keypoints
    ASSERT_FALSE(kps_charbonnier.empty());
    ASSERT_FALSE(kps_pm_g2.empty());

    // Check subpixel accuracy for DIFF_CHARBONNIER (issue #27134)
    bool hasSubpixel = false;
    for (size_t i = 0; i < kps_charbonnier.size(); i++)
    {
        float fx = kps_charbonnier[i].pt.x - std::floor(kps_charbonnier[i].pt.x);
        float fy = kps_charbonnier[i].pt.y - std::floor(kps_charbonnier[i].pt.y);
        if (fx > 1e-5f || fy > 1e-5f)
        {
            hasSubpixel = true;
            break;
        }
    }
    EXPECT_TRUE(hasSubpixel) << "KAZE with DIFF_CHARBONNIER should have subpixel keypoint coordinates";

    // Descriptor dimensions should match
    ASSERT_EQ(desc_charbonnier.cols, desc_pm_g2.cols);
}

}} // namespace