#include "generate.hpp"

#include <components/detournavigator/navmeshtilescache.hpp>
#include <components/detournavigator/preparednavmeshdata.hpp>
#include <components/detournavigator/recast.hpp>
#include <components/detournavigator/recastmesh.hpp>

#include <osg/Vec3f>

#include <RecastAlloc.h>

#include <gtest/gtest.h>

#include <random>
#include <stdexcept>

namespace
{
    using namespace testing;
    using namespace DetourNavigator;
    using namespace DetourNavigator::Tests;

    template <class T, class Random>
    void generateRecastArray(T*& values, int size, Random& random)
    {
        values = static_cast<T*>(permRecastAlloc(size * sizeof(T)));
        generateRange(values, values + static_cast<std::ptrdiff_t>(size), random);
    }

    template <class Random>
    void generate(rcPolyMesh& value, int size, Random& random)
    {
        value.nverts = size;
        value.maxpolys = size;
        value.nvp = size;
        value.npolys = size;
        rcVcopy(value.bmin, osg::Vec3f(-1, -2, -3).ptr());
        rcVcopy(value.bmax, osg::Vec3f(3, 2, 1).ptr());
        generateValue(value.cs, random);
        generateValue(value.ch, random);
        generateValue(value.borderSize, random);
        generateValue(value.maxEdgeError, random);
        generateRecastArray(value.verts, getVertsLength(value), random);
        generateRecastArray(value.polys, getPolysLength(value), random);
        generateRecastArray(value.regs, getRegsLength(value), random);
        generateRecastArray(value.flags, getFlagsLength(value), random);
        generateRecastArray(value.areas, getAreasLength(value), random);
    }

    template <class Random>
    void generate(rcPolyMeshDetail& value, int size, Random& random)
    {
        value.nmeshes = size;
        value.nverts = size;
        value.ntris = size;
        generateRecastArray(value.meshes, getMeshesLength(value), random);
        generateRecastArray(value.verts, getVertsLength(value), random);
        generateRecastArray(value.tris, getTrisLength(value), random);
    }

    template <class Random>
    void generate(PreparedNavMeshData& value, int size, Random& random)
    {
        generateValue(value.mUserId, random);
        generateValue(value.mCellHeight, random);
        generateValue(value.mCellSize, random);
        generate(value.mPolyMesh, size, random);
        generate(value.mPolyMeshDetail, size, random);
    }

    std::unique_ptr<PreparedNavMeshData> makePeparedNavMeshData(int size)
    {
        std::minstd_rand random;
        auto result = std::make_unique<PreparedNavMeshData>();
        generate(*result, size, random);
        return result;
    }

    std::unique_ptr<PreparedNavMeshData> clone(const PreparedNavMeshData& value)
    {
        return std::make_unique<PreparedNavMeshData>(value);
    }

    Mesh makeMesh()
    {
        std::vector<int> indices{ { 0, 1, 2 } };
        std::vector<float> vertices{ { 0, 0, 0, 1, 0, 0, 1, 1, 0 } };
        std::vector<AreaType> areaTypes{ 1, AreaType_ground };
        return Mesh(std::move(indices), std::move(vertices), std::move(areaTypes));
    }

    struct DetourNavigatorNavMeshTilesCacheTest : Test
    {
        const AgentBounds mAgentBounds{ CollisionShapeType::Aabb, { 1, 2, 3 } };
        const TilePosition mTilePosition{ 0, 0 };
        const Version mVersion{ 0, 0 };
        const Mesh mMesh{ makeMesh() };
        const std::vector<CellWater> mWater{};
        const std::vector<Heightfield> mHeightfields{};
        const std::vector<FlatHeightfield> mFlatHeightfields{};
        const std::vector<MeshSource> mSources{};
        const RecastMesh mRecastMesh{ mVersion, mMesh, mWater, mHeightfields, mFlatHeightfields, mSources };
        std::unique_ptr<PreparedNavMeshData> mPreparedNavMeshData{ makePeparedNavMeshData(3) };

        const std::size_t mRecastMeshSize = sizeof(mRecastMesh) + getSize(mRecastMesh);
        const std::size_t mRecastMeshWithWaterSize = mRecastMeshSize + sizeof(CellWater);
        const std::size_t mPreparedNavMeshDataSize = sizeof(*mPreparedNavMeshData) + getSize(*mPreparedNavMeshData);
    };

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, get_for_empty_cache_should_return_empty_value)
    {
        const std::size_t maxSize = 0;
        NavMeshTilesCache cache(maxSize);

        EXPECT_FALSE(cache.get(mAgentBounds, mTilePosition, mRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, set_for_not_enought_cache_size_should_return_empty_value)
    {
        const std::size_t maxSize = 0;
        NavMeshTilesCache cache(maxSize);

        EXPECT_FALSE(cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData)));
        EXPECT_NE(mPreparedNavMeshData, nullptr);
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, set_should_return_cached_value)
    {
        const std::size_t maxSize = mRecastMeshSize + mPreparedNavMeshDataSize;
        NavMeshTilesCache cache(maxSize);
        const auto copy = clone(*mPreparedNavMeshData);
        ASSERT_EQ(*mPreparedNavMeshData, *copy);

        const auto result = cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        ASSERT_TRUE(result);
        EXPECT_EQ(result.get(), *copy);
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, set_existing_element_should_return_cached_element)
    {
        const std::size_t maxSize = 2 * (mRecastMeshSize + mPreparedNavMeshDataSize);
        NavMeshTilesCache cache(maxSize);
        auto copy = clone(*mPreparedNavMeshData);
        const auto sameCopy = clone(*mPreparedNavMeshData);

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_EQ(mPreparedNavMeshData, nullptr);
        const auto result = cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(copy));
        ASSERT_TRUE(result);
        EXPECT_EQ(result.get(), *sameCopy);
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, get_should_return_cached_value)
    {
        const std::size_t maxSize = mRecastMeshSize + mPreparedNavMeshDataSize;
        NavMeshTilesCache cache(maxSize);
        const auto copy = clone(*mPreparedNavMeshData);

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        const auto result = cache.get(mAgentBounds, mTilePosition, mRecastMesh);
        ASSERT_TRUE(result);
        EXPECT_EQ(result.get(), *copy);
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, get_for_cache_miss_by_agent_half_extents_should_return_empty_value)
    {
        const std::size_t maxSize = 1;
        NavMeshTilesCache cache(maxSize);
        const AgentBounds absentAgentBounds{ CollisionShapeType::Aabb, { 1, 1, 1 } };

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_FALSE(cache.get(absentAgentBounds, mTilePosition, mRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, get_for_cache_miss_by_tile_position_should_return_empty_value)
    {
        const std::size_t maxSize = 1;
        NavMeshTilesCache cache(maxSize);
        const TilePosition unexistentTilePosition{ 1, 1 };

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_FALSE(cache.get(mAgentBounds, unexistentTilePosition, mRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, get_for_cache_miss_by_recast_mesh_should_return_empty_value)
    {
        const std::size_t maxSize = 1;
        NavMeshTilesCache cache(maxSize);
        const std::vector<CellWater> water(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh unexistentRecastMesh(mVersion, mMesh, water, mHeightfields, mFlatHeightfields, mSources);

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_FALSE(cache.get(mAgentBounds, mTilePosition, unexistentRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, set_should_replace_unused_value)
    {
        const std::size_t maxSize = mRecastMeshWithWaterSize + mPreparedNavMeshDataSize;
        NavMeshTilesCache cache(maxSize);

        const std::vector<CellWater> water(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh anotherRecastMesh(mVersion, mMesh, water, mHeightfields, mFlatHeightfields, mSources);
        auto anotherPreparedNavMeshData = makePeparedNavMeshData(3);
        const auto copy = clone(*anotherPreparedNavMeshData);

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        const auto result
            = cache.set(mAgentBounds, mTilePosition, anotherRecastMesh, std::move(anotherPreparedNavMeshData));
        ASSERT_TRUE(result);
        EXPECT_EQ(result.get(), *copy);
        EXPECT_FALSE(cache.get(mAgentBounds, mTilePosition, mRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, set_should_not_replace_used_value)
    {
        const std::size_t maxSize = mRecastMeshWithWaterSize + mPreparedNavMeshDataSize;
        NavMeshTilesCache cache(maxSize);

        const std::vector<CellWater> water(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh anotherRecastMesh(mVersion, mMesh, water, mHeightfields, mFlatHeightfields, mSources);
        auto anotherPreparedNavMeshData = makePeparedNavMeshData(3);

        const auto value = cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_FALSE(cache.set(mAgentBounds, mTilePosition, anotherRecastMesh, std::move(anotherPreparedNavMeshData)));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, set_should_replace_unused_least_recently_set_value)
    {
        const std::size_t maxSize = 2 * (mRecastMeshWithWaterSize + mPreparedNavMeshDataSize);
        NavMeshTilesCache cache(maxSize);
        const auto copy = clone(*mPreparedNavMeshData);

        const std::vector<CellWater> leastRecentlySetWater(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh leastRecentlySetRecastMesh(
            mVersion, mMesh, leastRecentlySetWater, mHeightfields, mFlatHeightfields, mSources);
        auto leastRecentlySetData = makePeparedNavMeshData(3);

        const std::vector<CellWater> mostRecentlySetWater(1, CellWater{ osg::Vec2i(), Water{ 2, 0.0f } });
        const RecastMesh mostRecentlySetRecastMesh(
            mVersion, mMesh, mostRecentlySetWater, mHeightfields, mFlatHeightfields, mSources);
        auto mostRecentlySetData = makePeparedNavMeshData(3);

        ASSERT_TRUE(
            cache.set(mAgentBounds, mTilePosition, leastRecentlySetRecastMesh, std::move(leastRecentlySetData)));
        ASSERT_TRUE(cache.set(mAgentBounds, mTilePosition, mostRecentlySetRecastMesh, std::move(mostRecentlySetData)));

        const auto result = cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_EQ(result.get(), *copy);

        EXPECT_FALSE(cache.get(mAgentBounds, mTilePosition, leastRecentlySetRecastMesh));
        EXPECT_TRUE(cache.get(mAgentBounds, mTilePosition, mostRecentlySetRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, set_should_replace_unused_least_recently_used_value)
    {
        const std::size_t maxSize = 2 * (mRecastMeshWithWaterSize + mPreparedNavMeshDataSize);
        NavMeshTilesCache cache(maxSize);

        const std::vector<CellWater> leastRecentlyUsedWater(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh leastRecentlyUsedRecastMesh(
            mVersion, mMesh, leastRecentlyUsedWater, mHeightfields, mFlatHeightfields, mSources);
        auto leastRecentlyUsedData = makePeparedNavMeshData(3);
        const auto leastRecentlyUsedCopy = clone(*leastRecentlyUsedData);

        const std::vector<CellWater> mostRecentlyUsedWater(1, CellWater{ osg::Vec2i(), Water{ 2, 0.0f } });
        const RecastMesh mostRecentlyUsedRecastMesh(
            mVersion, mMesh, mostRecentlyUsedWater, mHeightfields, mFlatHeightfields, mSources);
        auto mostRecentlyUsedData = makePeparedNavMeshData(3);
        const auto mostRecentlyUsedCopy = clone(*mostRecentlyUsedData);

        cache.set(mAgentBounds, mTilePosition, leastRecentlyUsedRecastMesh, std::move(leastRecentlyUsedData));
        cache.set(mAgentBounds, mTilePosition, mostRecentlyUsedRecastMesh, std::move(mostRecentlyUsedData));

        {
            const auto value = cache.get(mAgentBounds, mTilePosition, leastRecentlyUsedRecastMesh);
            ASSERT_TRUE(value);
            ASSERT_EQ(value.get(), *leastRecentlyUsedCopy);
        }

        {
            const auto value = cache.get(mAgentBounds, mTilePosition, mostRecentlyUsedRecastMesh);
            ASSERT_TRUE(value);
            ASSERT_EQ(value.get(), *mostRecentlyUsedCopy);
        }

        const auto copy = clone(*mPreparedNavMeshData);
        const auto result = cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_EQ(result.get(), *copy);

        EXPECT_FALSE(cache.get(mAgentBounds, mTilePosition, leastRecentlyUsedRecastMesh));
        EXPECT_TRUE(cache.get(mAgentBounds, mTilePosition, mostRecentlyUsedRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest,
        set_should_not_replace_unused_least_recently_used_value_when_item_does_not_not_fit_cache_max_size)
    {
        const std::size_t maxSize = 2 * (mRecastMeshWithWaterSize + mPreparedNavMeshDataSize);
        NavMeshTilesCache cache(maxSize);

        const std::vector<CellWater> water(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh tooLargeRecastMesh(mVersion, mMesh, water, mHeightfields, mFlatHeightfields, mSources);
        auto tooLargeData = makePeparedNavMeshData(10);

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        EXPECT_FALSE(cache.set(mAgentBounds, mTilePosition, tooLargeRecastMesh, std::move(tooLargeData)));
        EXPECT_TRUE(cache.get(mAgentBounds, mTilePosition, mRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest,
        set_should_not_replace_unused_least_recently_used_value_when_item_does_not_not_fit_size_of_unused_items)
    {
        const std::size_t maxSize = 2 * (mRecastMeshWithWaterSize + mPreparedNavMeshDataSize);
        NavMeshTilesCache cache(maxSize);

        const std::vector<CellWater> anotherWater(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh anotherRecastMesh(mVersion, mMesh, anotherWater, mHeightfields, mFlatHeightfields, mSources);
        auto anotherData = makePeparedNavMeshData(3);

        const std::vector<CellWater> tooLargeWater(1, CellWater{ osg::Vec2i(), Water{ 2, 0.0f } });
        const RecastMesh tooLargeRecastMesh(mVersion, mMesh, tooLargeWater, mHeightfields, mFlatHeightfields, mSources);
        auto tooLargeData = makePeparedNavMeshData(10);

        const auto value = cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        ASSERT_TRUE(value);
        ASSERT_TRUE(cache.set(mAgentBounds, mTilePosition, anotherRecastMesh, std::move(anotherData)));
        EXPECT_FALSE(cache.set(mAgentBounds, mTilePosition, tooLargeRecastMesh, std::move(tooLargeData)));
        EXPECT_TRUE(cache.get(mAgentBounds, mTilePosition, mRecastMesh));
        EXPECT_TRUE(cache.get(mAgentBounds, mTilePosition, anotherRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest,
        release_used_after_set_then_used_by_get_item_should_left_this_item_available)
    {
        const std::size_t maxSize = mRecastMeshWithWaterSize + mPreparedNavMeshDataSize;
        NavMeshTilesCache cache(maxSize);

        const std::vector<CellWater> water(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh anotherRecastMesh(mVersion, mMesh, water, mHeightfields, mFlatHeightfields, mSources);
        auto anotherData = makePeparedNavMeshData(3);

        const auto firstCopy = cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        ASSERT_TRUE(firstCopy);
        {
            const auto secondCopy = cache.get(mAgentBounds, mTilePosition, mRecastMesh);
            ASSERT_TRUE(secondCopy);
        }
        EXPECT_FALSE(cache.set(mAgentBounds, mTilePosition, anotherRecastMesh, std::move(anotherData)));
        EXPECT_TRUE(cache.get(mAgentBounds, mTilePosition, mRecastMesh));
    }

    TEST_F(DetourNavigatorNavMeshTilesCacheTest, release_twice_used_item_should_left_this_item_available)
    {
        const std::size_t maxSize = mRecastMeshWithWaterSize + mPreparedNavMeshDataSize;
        NavMeshTilesCache cache(maxSize);

        const std::vector<CellWater> water(1, CellWater{ osg::Vec2i(), Water{ 1, 0.0f } });
        const RecastMesh anotherRecastMesh(mVersion, mMesh, water, mHeightfields, mFlatHeightfields, mSources);
        auto anotherData = makePeparedNavMeshData(3);

        cache.set(mAgentBounds, mTilePosition, mRecastMesh, std::move(mPreparedNavMeshData));
        const auto firstCopy = cache.get(mAgentBounds, mTilePosition, mRecastMesh);
        ASSERT_TRUE(firstCopy);
        {
            const auto secondCopy = cache.get(mAgentBounds, mTilePosition, mRecastMesh);
            ASSERT_TRUE(secondCopy);
        }
        EXPECT_FALSE(cache.set(mAgentBounds, mTilePosition, anotherRecastMesh, std::move(anotherData)));
        EXPECT_TRUE(cache.get(mAgentBounds, mTilePosition, mRecastMesh));
    }
}