#include "light.h"

#include "../lib/glm/gtc/matrix_transform.hpp"

#include "shader.h"
#include "state.h"

Light::Light()
    : Entity()
    , type_(Type::DIRECTIONAL)
    , color_(1.0f, 1.0f, 1.0f)
    , intensity_(1.0f)
    , linear_attenuation_(0.0f)
{
}

void Light::prepare(int index, std::shared_ptr<Shader>& shader) const
{
	if (!shader)
		return;

	// Build uniform names for this light index
	std::string light_vector =
	    "lights[" + std::to_string(index) + "].vector";
	std::string light_color = "lights[" + std::to_string(index) + "].color";
	std::string light_intensity =
	    "lights[" + std::to_string(index) + "].intensity";
	std::string light_linear_att =
	    "lights[" + std::to_string(index) + "].linear_att";

	// Get uniform locations
	int vector_loc	   = shader->uniform_location(light_vector.c_str());
	int color_loc	   = shader->uniform_location(light_color.c_str());
	int intensity_loc  = shader->uniform_location(light_intensity.c_str());
	int linear_att_loc = shader->uniform_location(light_linear_att.c_str());

	// Calculate light vector in view space
	glm::vec4 light_vector_view;
	if (type_ == Type::DIRECTIONAL) {
		// For directional lights, w = 0
		glm::vec3 direction =
		    glm::normalize(position_); // Use position as direction
		light_vector_view =
		    state::view_matrix * glm::vec4(direction, 0.0f);
	} else {
		// For point lights, w = 1
		light_vector_view =
		    state::view_matrix * glm::vec4(position_, 1.0f);
	}

	// Set uniforms
	Shader::set_vec4(vector_loc, light_vector_view);
	Shader::set_vec3(color_loc, color_);
	Shader::set_float(intensity_loc, intensity_);
	Shader::set_float(linear_att_loc, linear_attenuation_);
}