#pragma once
// m2_material — Metin2-style forward material as a Godot ShaderMaterial.
//
// M2.5 infrastructure. The gr2 fixed-function texture-stage / blend data is not
// yet exposed by libgr2's POD API (see docs/GODOT-POC-PLAN.md §M2.5 gap list),
// so callers pick the blend mode heuristically for now. The shader itself
// already covers the common Metin2 cases: modulate(tex, vertex_color) + light,
// alpha-test, alpha-blend, additive.

#include <godot_cpp/classes/ref.hpp>

namespace godot {
class ShaderMaterial;
class Texture2D;
class ImageTexture;
} // namespace godot

namespace mtgodot {

enum class BlendMode {
	Opaque, // blend_mix, ALPHA=1, no discard
	Alpha, // blend_mix, sorted, uses texture alpha
	AlphaTest, // blend_mix, discard below alpha_scissor (cutout)
	Add, // blend_add (glow / effects)
};

struct MaterialDesc {
	godot::Ref<godot::Texture2D> albedo; // null -> flat white
	BlendMode blend = BlendMode::Opaque;
	float alpha_scissor = 0.5f;
	bool two_sided = true; // winding not yet verified per-model
	// GPU skinning: LBS with FULL per-bone affine matrices in the vertex shader
	// (no Skeleton3D -> no quaternion orthonormalization -> shear preserved).
	// `bones_tex` is RGBAF, size 3 x bone_count; columns 0..2 = the 3 columns of
	// the row-vector skin matrix (see metin2_model.cpp::gpu_skin).
	bool skinned = false;
	godot::Ref<godot::ImageTexture> bones_tex;

	// Sphere-map specular — port of CGrannyMaterial::__ApplySpecularRenderState
	// (EterGrnLib/Material.cpp:305). Opaque armor gets a metallic highlight from a
	// camera-space reflection-vector lookup into a shared sphere map, added on top
	// of the lit diffuse:
	//     out.rgb = tex.rgb*modulate  +  (tex.a * spec_power) * sphere(reflect_uv)
	// Client enables this per skin-part only when the equipped body-armor item's
	// item_proto `bSpecular > 0` (power = bSpecular/100); the base body is flat.
	// Dormant here until an equipment layer feeds a power: spec_power <= 0 ->
	// the shader branch is skipped and output is byte-identical to before.
	godot::Ref<godot::Texture2D> spec_map; // shared sphere map; null -> disabled
	float spec_power = 0.0f;               // fSpecularPower (D3DRS_TEXTUREFACTOR.a); 0 = off
};

godot::Ref<godot::ShaderMaterial> make_material(const MaterialDesc &d);

// Drop the extension-owned shader cache before GDExtension teardown. Materials
// still alive in the scene keep their own Ref, so this only removes the static
// lifetime that otherwise survives Godot's leak check.
void cleanup_material_shaders();

} // namespace mtgodot