// Copyright (2019-2022) Paul Scherrer Institute
// SPDX-License-Identifier: GPL-3.0-or-later

#include <catch2/catch.hpp>
#include "../writer/HDF5Objects.h"
#include "../image_analysis/IndexerWrapper.h"

#define make_unit_cell(a1,a2,a3,a4,a5,a6) UnitCell{.a = a1, .b = a2, .c = a3, .alpha = a4, .beta = a5, .gamma = a6}

TEST_CASE("CrystalLattice") {
    CrystalLattice l(make_unit_cell(50,60,80, 90, 90, 90));
    REQUIRE(l.Vec0().Length() == Approx(50));
    REQUIRE(l.Vec1().Length() == Approx(60));
    REQUIRE(l.Vec2().Length() == Approx(80));
    REQUIRE(angle_deg(l.Vec0(), l.Vec2()) == 90);
    REQUIRE(angle_deg(l.Vec0(), l.Vec1()) == 90);
    REQUIRE(angle_deg(l.Vec1(), l.Vec2()) == 90);

    l = CrystalLattice(make_unit_cell(30, 40, 70, 90, 95, 90));
    REQUIRE(l.Vec0().Length() == Approx(30));
    REQUIRE(l.Vec1().Length() == Approx(40));
    REQUIRE(l.Vec2().Length() == Approx(70));
    REQUIRE(angle_deg(l.Vec0(), l.Vec2()) == 95);
    REQUIRE(angle_deg(l.Vec0(), l.Vec1()) == 90);
    REQUIRE(angle_deg(l.Vec1(), l.Vec2()) == 90);

    l = CrystalLattice(make_unit_cell(45, 45, 70, 90, 90, 120));
    REQUIRE(l.Vec0().Length() == Approx(45));
    REQUIRE(l.Vec1().Length() == Approx(45));
    REQUIRE(l.Vec2().Length() == Approx(70));
    REQUIRE(angle_deg(l.Vec0(), l.Vec2()) == Approx(90));
    REQUIRE(angle_deg(l.Vec0(), l.Vec1()) == Approx(120));
    REQUIRE(angle_deg(l.Vec1(), l.Vec2()) == Approx(90));
}

TEST_CASE("CrystalLattice_ReciprocalLattice") {
    CrystalLattice l(make_unit_cell(50,60,80, 78, 80, 120));
    CrystalLattice rl = l.ReciprocalLattice();

    REQUIRE(l.Vec0() * rl.Vec0() == Approx(1.0));
    REQUIRE(l.Vec0() * rl.Vec1() < 1e-5);
    REQUIRE(l.Vec0() * rl.Vec2() < 1e-5);

    REQUIRE(l.Vec1() * rl.Vec0() < 1e-5);
    REQUIRE(l.Vec1() * rl.Vec1() == Approx(1.0));
    REQUIRE(l.Vec1() * rl.Vec2() < 1e-5);

    REQUIRE(l.Vec2() * rl.Vec0() < 1e-5);
    REQUIRE(l.Vec2() * rl.Vec1() < 1e-5);
    REQUIRE(l.Vec2() * rl.Vec2() == Approx(1.0));
}

TEST_CASE("CrystalLattice_EigenMatrix") {
    CrystalLattice l1(make_unit_cell(50,60,80, 78, 80, 120));
    auto m = l1.GetEigenMatrix();
    CrystalLattice l2(m);
    REQUIRE(l2.Vec0().x == Approx(l1.Vec0().x));
    REQUIRE(l2.Vec1().y == Approx(l1.Vec1().y));
    REQUIRE(l2.Vec2().x == Approx(l1.Vec2().x));
}

inline double round_err(double x) {
    return std::abs(x - std::round(x));
}

TEST_CASE("FastFeedbackIndexer","[Indexing]") {
    std::vector<Coord> hkl;
    for (int i = 1; i < 7; i++)
        for (int j = 1; j<6; j++)
            for (int k = 1; k < 4; k++)
                hkl.emplace_back(i,j,k);

    std::vector<UnitCell> cells;
    cells.emplace_back(make_unit_cell(30,40,50,90,90,90));
    cells.emplace_back(make_unit_cell(80,80,90,90,90,120));
    cells.emplace_back(make_unit_cell(40,45,80,90,82.5,90));

    for (auto &c: cells) {
        CrystalLattice l(c);
        CrystalLattice recip_l = l.ReciprocalLattice();

        std::vector<Coord> recip;
        recip.reserve(hkl.size());
        for (const auto &i: hkl)
            recip.emplace_back(i.x * recip_l.Vec0() + i.y * recip_l.Vec1() + i.z * recip_l.Vec2());

        IndexerWrapper wrapper;

        wrapper.Setup(c);
        auto ret = wrapper.Run(recip);
        REQUIRE(!ret.empty());

        //auto uc = ret[0].GetUnitCell();
        //REQUIRE(c.a == Approx(uc.a));
        //REQUIRE(c.b == Approx(uc.b));
        //REQUIRE(c.c == Approx(uc.c));
        REQUIRE(ret[0].indexed_spots_count == recip.size());

        double err[3] = {0.0, 0.0, 0.0};
        for (const auto &iter: recip) {
            err[0] += round_err(ret[0].l.Vec0() * iter);
            err[1] += round_err(ret[0].l.Vec1() * iter);
            err[2] += round_err(ret[0].l.Vec2() * iter);
        }
        REQUIRE (err[0] < 0.001 * recip.size());
        REQUIRE (err[1] < 0.001 * recip.size());
        REQUIRE (err[2] < 0.001 * recip.size());
    }
}