// SpeedTreeLib: the CSpeedTreeRT stand-in (platform/SpeedTreeLib/SpeedTreeRT.cpp) reads the .spt size and
// collision blocks the 40250 wrapper asks for (GetTreeSize, GetCollisionObject in OnUpdateCollisionData).
// The blocks are built here in the .spt token layout of the 40250 pack files.
#include "SpeedTreeLib/StdAfx.h"

#include <SpeedTreeRT.h>
#include "../../src/platform/EterLib/RenderCommands3D.h"

#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstring>
#include <string>
#include <vector>

static int g_failures = 0;
#define CHECK(cond)                                                    \
	do {                                                               \
		if (!(cond)) {                                                 \
			std::fprintf(stderr, "%s:%d: CHECK(%s)\n", __FILE__, __LINE__, #cond); \
			++g_failures;                                              \
		}                                                              \
	} while (0)
#define CHECK_NEAR(a, b) CHECK(std::fabs(double(a) - double(b)) < 1e-3)

namespace
{

struct Block
{
	std::vector<unsigned char> bytes;
	void i32(int32_t v) { bytes.insert(bytes.end(), reinterpret_cast<unsigned char *>(&v), reinterpret_cast<unsigned char *>(&v) + 4); }
	void f32(float v) { bytes.insert(bytes.end(), reinterpret_cast<unsigned char *>(&v), reinterpret_cast<unsigned char *>(&v) + 4); }
	void str(const std::string & s)
	{
		i32(int32_t(s.size()));
		bytes.insert(bytes.end(), s.begin(), s.end());
	}
};

// 1000 "__IdvSpt_02_", 1002, 2000 <bark>, 2001 size, 2002 variance, then filler up to the collision block.
Block header(float size, float variance)
{
	Block b;
	b.i32(1000);
	b.str("__IdvSpt_02_");
	b.i32(1002);
	b.i32(2000);
	b.str("BaobabBark.tga");
	b.i32(2001);
	b.f32(size);
	b.i32(2002);
	b.f32(variance);
	// texture-coordinate block: two leaf maps, one frond map, one billboard; corners (+r,+u) (-r,+u)
	// (-r,-u) (+r,-u) with v up (b1_baobab_rt.spt)
	b.i32(10000);
	b.i32(10002);
	b.i32(2);
	for (float f : { 0.5f, 0.25f, 0.25f, 0.25f, 0.25f, 0.0f, 0.5f, 0.0f })
		b.f32(f);
	for (float f : { 0.25f, 0.25f, 0.0f, 0.25f, 0.0f, 0.0f, 0.25f, 0.0f })
		b.f32(f);
	b.i32(10003);
	b.i32(1);
	for (float f : { 0.625f, 0.735f, 0.5f, 0.735f, 0.5f, 0.613f, 0.625f, 0.613f })
		b.f32(f);
	b.i32(10004);
	b.i32(1);
	for (float f : { 0.75f, 0.985f, 0.625f, 0.985f, 0.625f, 0.735f, 0.75f, 0.735f })
		b.f32(f);
	b.i32(10001);
	return b;
}

// The same block without leaf maps (palms, ferns, bare winter trees).
Block header_no_leaves()
{
	Block b;
	b.i32(1000);
	b.str("__IdvSpt_02_");
	b.i32(1002);
	b.i32(2000);
	b.str("PalmBark.tga");
	b.i32(2001);
	b.f32(50.0f);
	b.i32(2002);
	b.f32(0.0f);
	b.i32(10000);
	b.i32(10002);
	b.i32(0);
	b.i32(10003);
	b.i32(1);
	for (float f : { 0.375f, 0.625f, 0.25f, 0.625f, 0.25f, 0.5f, 0.375f, 0.5f })
		b.f32(f);
	b.i32(10004);
	b.i32(0);
	b.i32(10001);
	return b;
}

const float * leaf_texcoords(CSpeedTreeRT & tree, unsigned i)
{
	CSpeedTreeRT::SGeometry geometry;
	tree.GetGeometry(geometry, SpeedTree_LeafGeometry);
	CHECK(geometry.m_sLeaves0.m_usLeafCount > i);
	return geometry.m_sLeaves0.m_usLeafCount > i ? geometry.m_sLeaves0.m_pLeafMapTexCoords[i] : nullptr;
}

void test_leaf_texcoords()
{
	SetNativeTerrainRenderEnabled(true);
	CSpeedTreeRT::SetTextureFlip(true); // as CSpeedTreeWrapper::LoadTree

	Block b = header(1100.0f, 150.0f);
	CSpeedTreeRT tree;
	CHECK(tree.LoadTree(b.bytes.data(), unsigned(b.bytes.size())));
	CHECK(tree.Compute(nullptr, 1));
	// leaf 0: leaf map 0, v flipped
	if (const float * t = leaf_texcoords(tree, 0))
	{
		const float want[8] = { 0.5f, 0.75f, 0.25f, 0.75f, 0.25f, 1.0f, 0.5f, 1.0f };
		for (int k = 0; k < 8; ++k)
			CHECK_NEAR(t[k], want[k]);
	}
	// leaf 1: leaf map 1, mirrored in u by the proxy
	if (const float * t = leaf_texcoords(tree, 1))
	{
		const float want[8] = { 0.0f, 0.75f, 0.25f, 0.75f, 0.25f, 1.0f, 0.0f, 1.0f };
		for (int k = 0; k < 8; ++k)
			CHECK_NEAR(t[k], want[k]);
	}

	// no leaf maps: the proxy clusters use the frond map
	Block palm = header_no_leaves();
	CSpeedTreeRT palmTree;
	CHECK(palmTree.LoadTree(palm.bytes.data(), unsigned(palm.bytes.size())));
	CHECK(palmTree.Compute(nullptr, 1));
	if (const float * t = leaf_texcoords(palmTree, 0))
	{
		const float want[8] = { 0.375f, 0.375f, 0.25f, 0.375f, 0.25f, 0.5f, 0.375f, 0.5f };
		for (int k = 0; k < 8; ++k)
			CHECK_NEAR(t[k], want[k]);
	}
	SetNativeTerrainRenderEnabled(false);
}

void test_collision()
{
	Block b = header(1100.0f, 150.0f);
	b.i32(12000);
	b.i32(12003); // cylinder x y z radius height
	b.f32(0.0f);
	b.f32(0.0f);
	b.f32(0.0f);
	b.f32(164.47f);
	b.f32(582.55f);
	b.i32(12002); // sphere x y z radius
	b.f32(-10.44f);
	b.f32(18.5f);
	b.f32(775.42f);
	b.f32(450.15f);
	b.i32(12001);
	b.i32(13000);
	b.i32(13001);

	CSpeedTreeRT tree;
	CHECK(tree.LoadTree(b.bytes.data(), unsigned(b.bytes.size())));
	float size = 0.0f, variance = 0.0f;
	tree.GetTreeSize(size, variance);
	CHECK_NEAR(size, 1100.0f);
	CHECK_NEAR(variance, 150.0f);

	CHECK(tree.GetCollisionObjectCount() == 2);
	CSpeedTreeRT::ECollisionObjectType type = CSpeedTreeRT::CO_BOX;
	float pos[3] = {}, dim[3] = {};
	tree.GetCollisionObject(0, type, pos, dim);
	CHECK(type == CSpeedTreeRT::CO_CYLINDER);
	CHECK_NEAR(pos[0], 0.0f);
	CHECK_NEAR(pos[2], 0.0f);
	CHECK_NEAR(dim[0], 164.47f);
	CHECK_NEAR(dim[1], 582.55f);
	tree.GetCollisionObject(1, type, pos, dim);
	CHECK(type == CSpeedTreeRT::CO_SPHERE);
	CHECK_NEAR(pos[0], -10.44f);
	CHECK_NEAR(pos[1], 18.5f);
	CHECK_NEAR(pos[2], 775.42f);
	CHECK_NEAR(dim[0], 450.15f);

	// instances share the tree data
	CSpeedTreeRT * instance = tree.MakeInstance();
	CHECK(instance->GetCollisionObjectCount() == 2);
	delete instance;
}

void test_no_collision()
{
	// aloe flowers / ferns: no 12000 section, no collision objects
	Block b = header(50.0f, 0.0f);
	b.i32(13000);
	b.i32(13001);
	CSpeedTreeRT tree;
	CHECK(tree.LoadTree(b.bytes.data(), unsigned(b.bytes.size())));
	CHECK(tree.GetCollisionObjectCount() == 0);
}

} // namespace

int main()
{
	test_collision();
	test_no_collision();
	test_leaf_texcoords();
	if (g_failures)
	{
		std::fprintf(stderr, "port_speedtree_test: %d failure(s)\n", g_failures);
		return 1;
	}
	std::printf("port_speedtree_test: ok\n");
	return 0;
}