use crate::geometry;

pub enum InputRequirement {
  Required,
  Optional
}

pub struct ShaderInput {
  pub semantic: geometry::VertexSemantic,
  pub component_count: usize,
  pub data_type: geometry::AttributeType,
  pub requirement: InputRequirement
}

pub struct ShaderInputs {
  pub inputs: Vec<ShaderInput>,
}

impl ShaderInputs {
  pub fn new() -> Self {
    Self {
      inputs: vec![]
    }
  }

  pub fn required(
    mut self,
    semantic: geometry::VertexSemantic,
    component_count: usize,
    data_type: geometry::AttributeType
  ) -> Self {
    self.inputs.push(ShaderInput {
      semantic,
      data_type,
      component_count,
      requirement: InputRequirement::Required,
    });
    self
  }

  pub fn optional(
    mut self,
    semantic: geometry::VertexSemantic,
    component_count: usize,
    data_type: geometry::AttributeType
  ) -> Self {
    self.inputs.push(ShaderInput {
      semantic,
      data_type,
      component_count,
      requirement: InputRequirement::Optional,
    });
    self
  }
}