#include <gtest/gtest.h>
#include "ContourBands.hpp"
using namespace geopro::core;
using namespace geopro::render;

// 上采样 2x：色带边界更密 → 多边形数应多于不上采样。
TEST(ContourBands, UpsampleIncreasesDetail) {
    Grid g(3, 3);
    g.x = {0, 1, 2}; g.y = {0, 1, 2};
    for (int j = 0; j < 3; ++j)
        for (int i = 0; i < 3; ++i) g.valueAt(i, j) = static_cast<double>(i * i + j);
    g.vmin = 0; g.vmax = 6;
    ColorScale cs;
    cs.addStop(0, Rgba{0,0,255,255}); cs.addStop(3, Rgba{0,255,0,255}); cs.addStop(6, Rgba{255,0,0,255});
    ContourOptions a; a.upsample = 1; a.smooth = 0; a.simplifyTol = 0;
    ContourOptions b; b.upsample = 2; b.smooth = 0; b.simplifyTol = 0;
    auto ra = buildContourBands(g, cs, a);
    auto rb = buildContourBands(g, cs, b);
    EXPECT_GT(rb.bands.size(), ra.bands.size());
}

// 2x2 平滑梯度网格 + 2 段色阶 → 至少 1 个色带多边形，多边形顶点 >=3。
TEST(ContourBands, ProducesNonEmptyBands) {
    Grid g(3, 3);
    g.x = {0, 1, 2}; g.y = {0, 1, 2};
    for (int j = 0; j < 3; ++j)
        for (int i = 0; i < 3; ++i) g.valueAt(i, j) = static_cast<double>(i + j);  // 0..4
    g.vmin = 0; g.vmax = 4;
    ColorScale cs;
    cs.addStop(0.0, Rgba{0, 0, 255, 255});
    cs.addStop(2.0, Rgba{0, 255, 0, 255});
    cs.addStop(4.0, Rgba{255, 0, 0, 255});

    ContourOptions opt; opt.upsample = 1; opt.smooth = 0; opt.simplifyTol = 0;
    auto r = buildContourBands(g, cs, opt);
    ASSERT_FALSE(r.bands.empty());
    for (const auto& b : r.bands) EXPECT_GE(b.ring.size(), 3u);
}