#include <gtest/gtest.h>
#include "vde/curves/parallel_intersection.h"
#include <cmath>

using namespace vde::curves;
using namespace vde::core;

// Helper: create a simple NURBS line from (0,0) to (1,0)
static NurbsCurve make_line_curve() {
    std::vector<Point3D> cp = {{0,0,0}, {1,0,0}};
    std::vector<double> knots = {0, 0, 1, 1};
    std::vector<double> weights = {1, 1};
    return NurbsCurve(cp, knots, weights, 1);
}

TEST(ParallelIntersectionTest, CurveIntersection_Empty) {
    auto results = parallel_curve_intersections({}, {}, {});
    EXPECT_EQ(results.size(), 0u);
}

TEST(ParallelIntersectionTest, CurveIntersection_SinglePair) {
    auto c1 = make_line_curve();
    auto c2 = make_line_curve();
    std::vector<std::pair<int,int>> pairs = {{0, 0}};

    auto results = parallel_curve_intersections(pairs,
        std::vector<NurbsCurve>{c1},
        std::vector<NurbsCurve>{c2});
    EXPECT_EQ(results.size(), 1u);
}

TEST(ParallelIntersectionTest, SurfaceIntersection_Empty) {
    // Create two planes
    NurbsSurface a, b;
    auto results = parallel_surface_intersection(a, b);
    EXPECT_EQ(results.size(), 0u);
}

TEST(ParallelIntersectionTest, SurfaceIntersection_Batch) {
    std::vector<std::pair<int,int>> pairs;
    auto results = parallel_surface_intersections(pairs, {}, {});
    EXPECT_EQ(results.size(), 0u);
}