// SPDX-FileCopyrightText: 2026 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#include <catch2/catch_all.hpp>

#include <filesystem>
#include <fstream>
#include <map>
#include <stdexcept>

#include "../rugnux/RugnuxSweeps.h"

namespace {

// Inputs described by name alone: "<template>_<n>.cbf" frames, "<name>_rot.h5" / "<name>_still.h5"
// masters, "<name>.cxi" for the stills readers; the wavelength from a table.
struct FakeInputs {
    std::map<std::string, double> wavelength;
    int sweeps_described = 0;

    RugnuxInputDescription File(const std::string &f) const {
        RugnuxInputDescription d;
        if (f.ends_with(".cbf"))
            d.frame_template = RugnuxFrameTemplate(f);
        d.foreign = f.ends_with(".cxi");
        return d;
    }
    RugnuxInputDescription Sweep(const std::string &f) {
        sweeps_described++;
        RugnuxInputDescription d = File(f);
        d.rotation = f.ends_with(".cbf") || f.ends_with("_rot.h5");
        d.wavelength_A = wavelength.contains(f) ? wavelength.at(f) : 1.0;
        return d;
    }
    RugnuxSweepPlan Plan(const std::vector<std::string> &inputs) {
        return PlanRugnuxSweeps(inputs, [this](const std::string &f) { return File(f); },
                                [this](const std::string &f) { return Sweep(f); });
    }
};

}  // namespace

TEST_CASE("RugnuxFrameTemplate", "[Rugnux][portable]") {
    CHECK(RugnuxFrameTemplate("/d/x_1_0001.cbf") == "/d/x_1_####.cbf");
    CHECK(RugnuxFrameTemplate("x_00017.cbf.gz") == "x_#####.cbf.gz");
    CHECK(RugnuxFrameTemplate("formal.001") == "formal.###");
    CHECK(RugnuxFrameTemplate("noframe.cbf").empty());
}

TEST_CASE("PlanRugnuxSweeps_single_input_is_not_planned", "[Rugnux][portable]") {
    FakeInputs in;
    CHECK(in.Plan({"a_0001.cbf"}).sweeps.empty());
    CHECK(in.Plan({"run_rot.h5"}).sweeps.empty());
    CHECK(in.sweeps_described == 0);   // nothing is opened for one input
}

TEST_CASE("PlanRugnuxSweeps_frames_by_template", "[Rugnux][portable]") {
    FakeInputs in;
    SECTION("frames of one template are its one sweep, named by the first given") {
        const auto plan = in.Plan({"d/a_0003.cbf", "d/a_0001.cbf", "d/a_0002.cbf"});
        REQUIRE(plan.sweeps.size() == 1);
        CHECK(plan.sweeps[0].input == "d/a_0003.cbf");
        CHECK(plan.sweeps[0].frames);
    }
    SECTION("two templates are two sweeps, in the order given") {
        const auto plan = in.Plan({"d/b_0001.cbf", "d/b_0002.cbf", "d/a_0001.cbf"});
        REQUIRE(plan.sweeps.size() == 2);
        CHECK(plan.sweeps[0].input == "d/b_0001.cbf");
        CHECK(plan.sweeps[0].label == std::filesystem::path("d/b_####.cbf").string());
        CHECK(plan.sweeps[1].input == "d/a_0001.cbf");
        CHECK(plan.wavelength_A == Catch::Approx(1.0));
    }
    SECTION("the same name in two directories is two sweeps") {
        CHECK(in.Plan({"d1/a_0001.cbf", "d2/a_0001.cbf"}).sweeps.size() == 2);
    }
    SECTION("sweeps at different wavelengths are refused") {
        in.wavelength["d/b_0001.cbf"] = 1.2;
        CHECK_THROWS_AS(in.Plan({"d/a_0001.cbf", "d/b_0001.cbf"}), std::runtime_error);
    }
}

TEST_CASE("PlanRugnuxSweeps_masters", "[Rugnux][portable]") {
    FakeInputs in;
    SECTION("stills masters stay one stills run") {
        CHECK(in.Plan({"a_still.h5", "b_still.h5", "c_still.h5"}).sweeps.empty());
        CHECK(in.sweeps_described == 1);   // the first decides; the stills reader refuses a rotation one
    }
    SECTION("rotation masters are a sweep each") {
        const auto plan = in.Plan({"a_rot.h5", "b_rot.h5"});
        REQUIRE(plan.sweeps.size() == 2);
        CHECK(plan.sweeps[1].input == "b_rot.h5");
        CHECK_FALSE(plan.sweeps[0].frames);
    }
    SECTION("rotation and stills are refused") {
        CHECK_THROWS_AS(in.Plan({"a_rot.h5", "b_still.h5"}), std::runtime_error);
    }
    SECTION("rotation masters at different wavelengths are refused") {
        in.wavelength["b_rot.h5"] = 0.98;
        CHECK_THROWS_AS(in.Plan({"a_rot.h5", "b_rot.h5"}), std::runtime_error);
    }
    SECTION("a wavelength within the tolerance is the same") {
        in.wavelength["b_rot.h5"] = 1.0 + 1e-4;
        CHECK(in.Plan({"a_rot.h5", "b_rot.h5"}).sweeps.size() == 2);
    }
}

TEST_CASE("PlanRugnuxSweeps_leaves_the_stills_readers_and_mixtures_alone", "[Rugnux][portable]") {
    FakeInputs in;
    CHECK(in.Plan({"a.cxi", "b.cxi"}).sweeps.empty());
    CHECK(in.Plan({"a_0001.cbf", "b_rot.h5"}).sweeps.empty());   // the readers refuse the mix, as before
    CHECK(in.sweeps_described == 0);
}

TEST_CASE("RugnuxSiblingSweeps", "[Rugnux][portable]") {
    namespace fs = std::filesystem;
    const fs::path dir = fs::path("rugnux_sweeps_siblings");
    fs::remove_all(dir);
    fs::create_directories(dir);
    for (const char *name: {"a_0001.cbf", "a_0002.cbf", "b_0001.cbf", "b_0002.cbf", "b_0003.cbf", "c_0001.cbf.gz",
                            "notes.txt", "x_master.h5", "y_master.h5"})
        std::ofstream(dir / name) << "x";

    RugnuxSweepPlan plan;
    plan.sweeps.push_back({(dir / "a_0001.cbf").string(), RugnuxFrameTemplate((dir / "a_0001.cbf").string()), true});
    plan.sweeps.push_back({(dir / "x_master.h5").string(), (dir / "x_master.h5").string(), false});
    const auto siblings = RugnuxSiblingSweeps(plan, {".cbf"});
    REQUIRE(siblings.size() == 3);
    CHECK(siblings[0] == (dir / "b_####.cbf").string() + " (3 frames)");
    CHECK(siblings[1] == (dir / "c_####.cbf.gz").string() + " (1 frame)");
    CHECK(siblings[2] == (dir / "y_master.h5").string());
    fs::remove_all(dir);
}