/*
 * SOFA info utility for inspecting SOFA file metrics and determining HRTF
 * utility compatible layouts.
 *
 * Copyright (C) 2018-2019  Christopher Fitzgerald
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Or visit:  http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 */

#include "config.h"

#include <memory>
#include <ranges>
#include <span>
#include <string>
#include <string_view>
#include <vector>

#include "altypes.hpp"
#include "fmt/base.h"
#include "sofa-support.h"

#include "mysofa.h"

#include "win_main_utf8.h"

#if HAVE_CXXMODULES
import gsl;
#else
#include "gsl/gsl"
#endif

namespace {

using namespace std::string_view_literals;

void PrintSofaAttributes(const std::string_view prefix, MYSOFA_ATTRIBUTE *attribute)
{
    while(attribute)
    {
        fmt::println("{}.{}: {}", prefix, attribute->name ? attribute->name : "<null>",
            attribute->value ? attribute->value : "<null>");
        attribute = attribute->next;
    }
}

void PrintSofaArray(const std::string_view prefix, MYSOFA_ARRAY *array, bool showValues=true)
{
    PrintSofaAttributes(prefix, array->attributes);
    if(showValues)
    {
        const auto values = std::span{array->values, array->elements};
        for(size_t i{0u};i < values.size();++i)
            fmt::println("{}[{}]: {:.6f}", prefix, i, values[i]);
    }
    else
        fmt::println("{}[...]: <{} values suppressed>", prefix, array->elements);
}

/* Attempts to produce a compatible layout.  Most data sets tend to be
 * uniform and have the same major axis as used by OpenAL Soft's HRTF model.
 * This will remove outliers and produce a maximally dense layout when
 * possible.  Those sets that contain purely random measurements or use
 * different major axes will fail.
 */
void PrintCompatibleLayout(const std::span<const float> xyzs)
{
    fmt::println("");

    auto fds = GetCompatibleLayout(xyzs);
    if(fds.empty())
    {
        fmt::println("No compatible field layouts in SOFA file.");
        return;
    }

    auto used_elems = 0u;
    for(size_t fi{0u};fi < fds.size();++fi)
    {
        for(unsigned ei{fds[fi].mEvStart};ei < fds[fi].mEvCount;++ei)
            used_elems += fds[fi].mAzCounts[ei];
    }

    fmt::print("Compatible Layout ({} of {} measurements):\n\ndistance = {:.3f}", used_elems,
        xyzs.size()/3, fds[0].mDistance);
    for(size_t fi{1u};fi < fds.size();fi++)
        fmt::print(", {:.3f}", fds[fi].mDistance);

    fmt::print("\nazimuths = ");
    for(size_t fi{0u};fi < fds.size();++fi)
    {
        for(unsigned ei{0u};ei < fds[fi].mEvStart;++ei)
            fmt::print("{}{}", fds[fi].mAzCounts[fds[fi].mEvCount - 1 - ei], ", ");
        for(unsigned ei{fds[fi].mEvStart};ei < fds[fi].mEvCount;++ei)
            fmt::print("{}{}", fds[fi].mAzCounts[ei],
                (ei < (fds[fi].mEvCount - 1)) ? ", " :
                (fi < (fds.size() - 1)) ? ";\n           " : "\n");
    }
}

// Load and inspect the given SOFA file.
void SofaInfo(const std::string &filename)
{
    int err;
    MySofaHrtfPtr sofa{mysofa_load(filename.c_str(), &err)};
    if(!sofa)
    {
        fmt::println("Error: Could not load source file '{}' ({}).", filename,
            SofaErrorStr(err));
        return;
    }

    /* NOTE: Some valid SOFA files are failing this check. */
    err = mysofa_check(sofa.get());
    if(err != MYSOFA_OK)
        fmt::println("Warning: Supposedly malformed source file '{}' ({}).", filename,
            SofaErrorStr(err));

    mysofa_tocartesian(sofa.get());

    PrintSofaAttributes("Info", sofa->attributes);

    fmt::println("Measurements: {}", sofa->M);
    fmt::println("Receivers: {}", sofa->R);
    fmt::println("Emitters: {}", sofa->E);
    fmt::println("Samples: {}", sofa->N);

    PrintSofaArray("SampleRate"sv, &sofa->DataSamplingRate);
    PrintSofaArray("DataDelay"sv, &sofa->DataDelay);
    PrintSofaArray("SourcePosition"sv, &sofa->SourcePosition, false);

    PrintCompatibleLayout(std::span{sofa->SourcePosition.values, sofa->M*3_uz});
}

int main(std::span<std::string_view> args)
{
    if(args.size() != 2)
    {
        fmt::println("Usage: {} <sofa-file>", args[0]);
        return 0;
    }

    SofaInfo(std::string{args[1]});

    return 0;
}

} /* namespace */

int main(int argc, char **argv)
{
    auto args = std::vector<std::string_view>(gsl::narrow<unsigned int>(argc));
    std::ranges::copy(std::views::counted(argv, argc), args.begin());
    return main(std::span{args});
}
