// Masked cube shader - based on renderer_3d.wgsl with mask sampling
#include "common_uniforms"
#include "math/common_utils"
#include "math/sdf_utils"

@group(0) @binding(0) var<uniform> globals: GlobalUniforms;
@group(0) @binding(1) var<storage, read> object_data: ObjectsBuffer;
@group(0) @binding(3) var noise_tex: texture_2d<f32>;
@group(0) @binding(4) var noise_sampler: sampler;
@group(0) @binding(5) var sky_tex: texture_2d<f32>;

@group(1) @binding(0) var mask_tex: texture_2d<f32>;
@group(1) @binding(1) var mask_sampler: sampler;

struct VertexOutput {
  @builtin(position) position: vec4<f32>,
  @location(0) local_pos: vec3<f32>,
  @location(1) color: vec4<f32>,
  @location(2) @interpolate(flat) instance_index: u32,
  @location(3) world_pos: vec3<f32>,
  @location(4) transformed_normal: vec3<f32>,
};

@vertex
fn vs_main(@builtin(vertex_index) vertex_index: u32,
           @builtin(instance_index) instance_index: u32) -> VertexOutput {
  var pos = array<vec3<f32>, 36>(
    vec3(-1.0, -1.0,  1.0), vec3( 1.0, -1.0,  1.0), vec3( 1.0,  1.0,  1.0),
    vec3(-1.0, -1.0,  1.0), vec3( 1.0,  1.0,  1.0), vec3(-1.0,  1.0,  1.0),
    vec3(-1.0, -1.0, -1.0), vec3(-1.0,  1.0, -1.0), vec3( 1.0,  1.0, -1.0),
    vec3(-1.0, -1.0, -1.0), vec3( 1.0,  1.0, -1.0), vec3( 1.0, -1.0, -1.0),
    vec3(-1.0,  1.0, -1.0), vec3(-1.0,  1.0,  1.0), vec3( 1.0,  1.0,  1.0),
    vec3(-1.0,  1.0, -1.0), vec3( 1.0,  1.0,  1.0), vec3( 1.0,  1.0, -1.0),
    vec3(-1.0, -1.0, -1.0), vec3( 1.0, -1.0, -1.0), vec3( 1.0, -1.0,  1.0),
    vec3(-1.0, -1.0, -1.0), vec3( 1.0, -1.0,  1.0), vec3(-1.0, -1.0,  1.0),
    vec3( 1.0, -1.0, -1.0), vec3( 1.0,  1.0, -1.0), vec3( 1.0,  1.0,  1.0),
    vec3( 1.0, -1.0, -1.0), vec3( 1.0,  1.0,  1.0), vec3( 1.0, -1.0,  1.0),
    vec3(-1.0, -1.0, -1.0), vec3(-1.0, -1.0,  1.0), vec3(-1.0,  1.0,  1.0),
    vec3(-1.0, -1.0, -1.0), vec3(-1.0,  1.0,  1.0), vec3(-1.0,  1.0, -1.0)
  );

  var p = pos[vertex_index];
  let obj = object_data.objects[instance_index];
  let world_pos = obj.model * vec4<f32>(p, 1.0);
  let clip_pos = globals.view_proj * world_pos;

  var out: VertexOutput;
  out.position = clip_pos;
  out.local_pos = p;
  out.color = obj.color;
  out.instance_index = instance_index;
  out.world_pos = world_pos.xyz;
  out.transformed_normal = normalize(vec3<f32>(0.0, 1.0, 0.0));

  return out;
}

#include "render/scene_query_mode"
#include "render/shadows"
#include "render/lighting_utils"
#include "ray_box"

struct FragmentOutput {
  @location(0) color: vec4<f32>,
  @builtin(frag_depth) depth: f32,
};

@fragment
fn fs_main(in: VertexOutput) -> FragmentOutput {
  let screen_uv = in.position.xy / globals.resolution;
  let mask_value = textureSample(mask_tex, mask_sampler, screen_uv).r;

  if (mask_value < 0.5) {
    discard;
  }

  let obj = object_data.objects[in.instance_index];
  let obj_type = obj.params.x;

  var p: vec3<f32>;
  var normal: vec3<f32>;
  var base_color = in.color.rgb;
  let light_dir = normalize(vec3<f32>(1.0, 1.0, 1.0));

  let ray_origin = globals.camera_pos_time.xyz;
  let ray_dir = normalize(in.world_pos - ray_origin);
  let inv_model = obj.inv_model;

  let local_origin = (inv_model * vec4<f32>(ray_origin, 1.0)).xyz;
  let local_dir = normalize((inv_model * vec4<f32>(ray_dir, 0.0)).xyz);

  let t = ray_box(local_origin, local_dir, vec3<f32>(-1.0), vec3<f32>(1.0));
  if (t.y < 0.0) {
    discard;
  }

  let t_start = max(t.x, 0.0);
  let t_end = t.y;

  var t_march = t_start;
  let max_steps = 128;
  var hit = false;
  var local_p = vec3<f32>(0.0);

  for (var step = 0; step < max_steps; step++) {
    local_p = local_origin + t_march * local_dir;
    let d = sdBox(local_p, vec3<f32>(1.0));

    if (d < 0.001) {
      hit = true;
      break;
    }

    t_march += max(d * 0.5, 0.001);
    if (t_march > t_end) {
      break;
    }
  }

  if (!hit) {
    discard;
  }

  p = local_p;
  let eps = 0.001;
  normal = normalize(vec3<f32>(
    sdBox(p + vec3<f32>(eps, 0.0, 0.0), vec3<f32>(1.0)) -
    sdBox(p - vec3<f32>(eps, 0.0, 0.0), vec3<f32>(1.0)),
    sdBox(p + vec3<f32>(0.0, eps, 0.0), vec3<f32>(1.0)) -
    sdBox(p - vec3<f32>(0.0, eps, 0.0), vec3<f32>(1.0)),
    sdBox(p + vec3<f32>(0.0, 0.0, eps), vec3<f32>(1.0)) -
    sdBox(p - vec3<f32>(0.0, 0.0, eps), vec3<f32>(1.0))
  ));

  let world_p = (obj.model * vec4<f32>(p, 1.0)).xyz;
  let world_normal = normalize((obj.model * vec4<f32>(normal, 0.0)).xyz);

  let bump_strength = 0.3;
  let bump_scale = 4.0;
  let noise_uv = world_p.xy * bump_scale;
  let noise_val = textureSample(noise_tex, noise_sampler, noise_uv).r;
  let bump_offset = (noise_val - 0.5) * bump_strength;

  let bumped_normal = normalize(world_normal + vec3<f32>(bump_offset));

  let diffuse = max(dot(bumped_normal, light_dir), 0.0);
  let ambient = 0.3;
  let lighting = ambient + diffuse * 0.7;

  let final_color = base_color * lighting;

  let clip_p = globals.view_proj * vec4<f32>(world_p, 1.0);
  let depth = clip_p.z / clip_p.w;

  var out: FragmentOutput;
  out.color = vec4<f32>(final_color, 1.0);
  out.depth = depth;

  return out;
}