// Copyright (c) 2014, The Monero Project
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#include "gtest/gtest.h"

#include "fcmp/fcmp.h"
#include "misc_log_ex.h"

#include <cmath>

static const fcmp::Leaves generate_leaves(const std::size_t num_leaves)
{
    std::vector<fcmp::LeafTuple> tuples;
    tuples.reserve(num_leaves);

    for (std::size_t i = 0; i < num_leaves; ++i)
    {
        // Generate random output tuple
        crypto::secret_key o,c;
        crypto::public_key O,C;
        crypto::generate_keys(O, o, o, false);
        crypto::generate_keys(C, c, c, false);

        tuples.emplace_back(fcmp::output_to_leaf_tuple(O, C));
    }

    return fcmp::Leaves{
        .start_idx = 0,
        .tuples    = std::move(tuples)
    };
}

static void log_tree_extension(const fcmp::TreeExtension<fcmp::Helios, fcmp::Selene> &tree_extension)
{
    const auto &c1_extensions = tree_extension.c1_layer_extensions;
    const auto &c2_extensions = tree_extension.c2_layer_extensions;

    MDEBUG("Tree extension has " << tree_extension.leaves.tuples.size() << " leaves, "
        << c1_extensions.size() << " helios layers, " <<  c2_extensions.size() << " selene layers");

    MDEBUG("Leaf start idx: " << tree_extension.leaves.start_idx);
    for (std::size_t i = 0; i < tree_extension.leaves.tuples.size(); ++i)
    {
        const auto &leaf = tree_extension.leaves.tuples[i];

        const auto O_x = fcmp::SELENE.to_string(leaf.O_x);
        const auto I_x = fcmp::SELENE.to_string(leaf.I_x);
        const auto C_x = fcmp::SELENE.to_string(leaf.C_x);

        MDEBUG("Leaf idx " << ((i*fcmp::LEAF_TUPLE_SIZE) + tree_extension.leaves.start_idx) << " : { O_x: " << O_x << " , I_x: " << I_x << " , C_x: " << C_x << " }");
    }

    bool use_c2 = true;
    std::size_t c1_idx = 0;
    std::size_t c2_idx = 0;
    for (std::size_t i = 0; i < (c1_extensions.size() + c2_extensions.size()); ++i)
    {
        if (use_c2)
        {
            CHECK_AND_ASSERT_THROW_MES(c2_idx < c2_extensions.size(), "unexpected c2 layer");

            const fcmp::LayerExtension<fcmp::Selene> &c2_layer = c2_extensions[c2_idx];
            MDEBUG("Selene tree extension start idx: " << c2_layer.start_idx);

            for (std::size_t j = 0; j < c2_layer.hashes.size(); ++j)
                MDEBUG("Hash idx: " << (j + c2_layer.start_idx) << " , hash: " << fcmp::SELENE.to_string(c2_layer.hashes[j]));

            ++c2_idx;
        }
        else
        {
            CHECK_AND_ASSERT_THROW_MES(c1_idx < c1_extensions.size(), "unexpected c1 layer");

            const fcmp::LayerExtension<fcmp::Helios> &c1_layer = c1_extensions[c1_idx];
            MDEBUG("Helios tree extension start idx: " << c1_layer.start_idx);

            for (std::size_t j = 0; j < c1_layer.hashes.size(); ++j)
                MDEBUG("Hash idx: " << (j + c1_layer.start_idx) << " , hash: " << fcmp::HELIOS.to_string(c1_layer.hashes[j]));

            ++c1_idx;
        }

        use_c2 = !use_c2;
    }
}

static void log_tree(const fcmp::Tree<fcmp::Helios, fcmp::Selene> &tree)
{
    MDEBUG("Tree has " << tree.leaves.size() << " leaves, "
        << tree.c1_layers.size() << " helios layers, " <<  tree.c2_layers.size() << " selene layers");

    for (std::size_t i = 0; i < tree.leaves.size(); ++i)
    {
        const auto &leaf = tree.leaves[i];

        const auto O_x = fcmp::SELENE.to_string(leaf.O_x);
        const auto I_x = fcmp::SELENE.to_string(leaf.I_x);
        const auto C_x = fcmp::SELENE.to_string(leaf.C_x);

        MDEBUG("Leaf idx " << i << " : { O_x: " << O_x << " , I_x: " << I_x << " , C_x: " << C_x << " }");
    }

    bool use_c2 = true;
    std::size_t c1_idx = 0;
    std::size_t c2_idx = 0;
    for (std::size_t i = 0; i < (tree.c1_layers.size() + tree.c2_layers.size()); ++i)
    {
        if (use_c2)
        {
            CHECK_AND_ASSERT_THROW_MES(c2_idx < tree.c2_layers.size(), "unexpected c2 layer");

            const fcmp::Layer<fcmp::Selene> &c2_layer = tree.c2_layers[c2_idx];
            MDEBUG("Selene layer size: " << c2_layer.size() << " , tree layer: " << i);

            for (std::size_t j = 0; j < c2_layer.size(); ++j)
                MDEBUG("Hash idx: " << j << " , hash: " << fcmp::SELENE.to_string(c2_layer[j]));

            ++c2_idx;
        }
        else
        {
            CHECK_AND_ASSERT_THROW_MES(c1_idx < tree.c1_layers.size(), "unexpected c1 layer");

            const fcmp::Layer<fcmp::Helios> &c1_layer = tree.c1_layers[c1_idx];
            MDEBUG("Helios layer size: " << c1_layer.size() << " , tree layer: " << i);

            for (std::size_t j = 0; j < c1_layer.size(); ++j)
                MDEBUG("Hash idx: " << j << " , hash: " << fcmp::HELIOS.to_string(c1_layer[j]));

            ++c1_idx;
        }

        use_c2 = !use_c2;
    }
}

static void log_last_chunks(const fcmp::LastChunks<fcmp::Helios, fcmp::Selene> &last_chunks)
{
    const auto &c1_last_chunks = last_chunks.c1_last_chunks;
    const auto &c2_last_chunks = last_chunks.c2_last_chunks;

    MDEBUG("Total of " << c1_last_chunks.size() << " Helios last chunks and "
        << c2_last_chunks.size() << " Selene last chunks");

    bool use_c2 = true;
    std::size_t c1_idx = 0;
    std::size_t c2_idx = 0;
    for (std::size_t i = 0; i < (c1_last_chunks.size() + c2_last_chunks.size()); ++i)
    {
        if (use_c2)
        {
            CHECK_AND_ASSERT_THROW_MES(c2_idx < c2_last_chunks.size(), "unexpected c2 layer");

            const fcmp::LastChunkData<fcmp::Selene> &last_chunk = c2_last_chunks[c2_idx];

            MDEBUG("child_offset: "         << last_chunk.child_offset
                << " , last_child: "        << fcmp::SELENE.to_string(last_chunk.last_child)
                << " , last_parent: "       << fcmp::SELENE.to_string(last_chunk.last_parent)
                << " , child_layer_size: "  << last_chunk.child_layer_size
                << " , parent_layer_size: " << last_chunk.parent_layer_size);

            ++c2_idx;
        }
        else
        {
            CHECK_AND_ASSERT_THROW_MES(c1_idx < c1_last_chunks.size(), "unexpected c1 layer");

            const fcmp::LastChunkData<fcmp::Helios> &last_chunk = c1_last_chunks[c1_idx];

            MDEBUG("child_offset: "         << last_chunk.child_offset
                << " , last_child: "        << fcmp::HELIOS.to_string(last_chunk.last_child)
                << " , last_parent: "       << fcmp::HELIOS.to_string(last_chunk.last_parent)
                << " , child_layer_size: "  << last_chunk.child_layer_size
                << " , parent_layer_size: " << last_chunk.parent_layer_size);

            ++c1_idx;
        }

        use_c2 = !use_c2;
    }
}

TEST(fcmp_tree, grow_tree)
{
    // TODO: 1 .. std::pow(fcmp::SELENE.WIDTH, 5)+2
    const std::vector<std::size_t> N_LEAVES{
        1,
        2,
        3,
        fcmp::SELENE.WIDTH - 1,
        fcmp::SELENE.WIDTH,
        fcmp::SELENE.WIDTH + 1,
        (std::size_t)std::pow(fcmp::SELENE.WIDTH, 2) - 1,
        (std::size_t)std::pow(fcmp::SELENE.WIDTH, 2),
        (std::size_t)std::pow(fcmp::SELENE.WIDTH, 2) + 1,
        (std::size_t)std::pow(fcmp::SELENE.WIDTH, 3),
        (std::size_t)std::pow(fcmp::SELENE.WIDTH, 4),
        (std::size_t)std::pow(fcmp::SELENE.WIDTH, 5)
    };

    for (const auto &init_leaves : N_LEAVES)
    {
        for (const auto &ext_leaves : N_LEAVES)
        {
            MDEBUG("Adding " << init_leaves << " leaves to tree, then extending by " << ext_leaves << " leaves");

            fcmp::Tree<fcmp::Helios, fcmp::Selene> global_tree;

            // TODO: use a class that's initialized with the curve cycle and don't need to call templated functions with curve instances every time

            // Initially extend global tree by `init_leaves`
            {
                MDEBUG("Adding " << init_leaves << " leaves to tree");

                const auto tree_extension = fcmp::get_tree_extension<fcmp::Helios, fcmp::Selene>(
                    fcmp::LastChunks<fcmp::Helios, fcmp::Selene>{},
                    generate_leaves(init_leaves),
                    fcmp::HELIOS,
                    fcmp::SELENE);

                log_tree_extension(tree_extension);

                fcmp::extend_tree<fcmp::Helios, fcmp::Selene>(
                    tree_extension,
                    fcmp::HELIOS,
                    fcmp::SELENE,
                    global_tree);

                log_tree(global_tree);

                const bool validated = fcmp::validate_tree<fcmp::Helios, fcmp::Selene>(
                    global_tree,
                    fcmp::HELIOS,
                    fcmp::SELENE);

                ASSERT_TRUE(validated);

                MDEBUG("Successfully added initial " << init_leaves << " leaves to tree");
            }

            // Then extend the global tree again by `ext_leaves`
            {
                MDEBUG("Extending tree by " << ext_leaves << " leaves");

                const auto last_chunks = fcmp::get_last_chunks<fcmp::Helios, fcmp::Selene>(
                    fcmp::HELIOS,
                    fcmp::SELENE,
                    global_tree);

                log_last_chunks(last_chunks);

                const auto tree_extension = fcmp::get_tree_extension<fcmp::Helios, fcmp::Selene>(
                    last_chunks,
                    generate_leaves(ext_leaves),
                    fcmp::HELIOS,
                    fcmp::SELENE);

                log_tree_extension(tree_extension);

                fcmp::extend_tree<fcmp::Helios, fcmp::Selene>(
                    tree_extension,
                    fcmp::HELIOS,
                    fcmp::SELENE,
                    global_tree);

                log_tree(global_tree);

                const bool validated = fcmp::validate_tree<fcmp::Helios, fcmp::Selene>(
                    global_tree,
                    fcmp::HELIOS,
                    fcmp::SELENE);

                ASSERT_TRUE(validated);

                MDEBUG("Successfully extended by " << ext_leaves << " leaves");
            }
        }
    }
}