// SPDX-License-Identifier: MIT
// SPDX-FileCopyrightText: 2026 Martino Ferrari

#include <plot/render/program.hpp>

#include <plot/render/shaders.hpp>

namespace plot::render {

bool LineProgram::create(Status* st) noexcept {
  // plot::gl::Program::from_source() reports Unsupported while
  // plot::gl::available() is false and GLFailure when the driver rejects the
  // GLSL. Propagating it is the whole point of returning a bool here: the
  // caller must not end up drawing with a program that never linked.
  program_ = gl::Program::from_source(kLineVS, kLineFS, st);
  return program_.id() != 0;
}

void LineProgram::set_scale(Vec2 data_to_px) const noexcept {
  program_.set_uniform("u_scale", data_to_px);
}

void LineProgram::set_offset(Vec2 px) const noexcept { program_.set_uniform("u_offset", px); }

void LineProgram::set_viewport(Vec2 px) const noexcept { program_.set_uniform("u_viewport", px); }

void LineProgram::set_width(f32 px) const noexcept { program_.set_uniform("u_width", px); }

void LineProgram::set_dash(Vec2 on_off) const noexcept {
  program_.set_uniform("u_dash", on_off);
}

void LineProgram::set_color(Color color) const noexcept { program_.set_uniform("u_color", color); }

void LineProgram::set_aa(f32 px) const noexcept { program_.set_uniform("u_aa", px); }

void LineProgram::set_snap(bool on) const noexcept {
  program_.set_uniform("u_snap", on ? 1.0f : 0.0f);
}

bool TextProgram::create(Status* st) noexcept {
  program_ = gl::Program::from_source(kTextVS, kTextFS, st);
  if (program_.id() == 0) {
    return false;
  }
  // The atlas is bound to texture unit 0 by plot::gl::Texture::bind(), so the
  // sampler has to point there. It is set once, here, not per frame.
  program_.use();
  program_.set_uniform_int("u_atlas", 0);
  return true;
}

void TextProgram::set_viewport(Vec2 px) const noexcept { program_.set_uniform("u_viewport", px); }

void TextProgram::set_px_range(Vec2 px) const noexcept { program_.set_uniform("u_px_range", px); }

void TextProgram::set_glyph_uv(Vec2 uv) const noexcept { program_.set_uniform("u_glyph_uv", uv); }

void TextProgram::set_texture_size(Vec2 texels) const noexcept {
  program_.set_uniform("u_tex_size", texels);
}

bool DensityProgram::create(Status* st) noexcept {
  program_ = gl::Program::from_source(kDensityVS, kDensityFS, st);
  if (program_.id() == 0) {
    return false;
  }
  // The grid texture is bound to texture unit 0 by plot::gl::Texture::bind(), so the sampler
  // has to point there. Set once, here, not per frame -- the same shape as the text program's.
  program_.use();
  program_.set_uniform_int("u_density", 0);
  return true;
}

void DensityProgram::set_viewport(Vec2 px) const noexcept { program_.set_uniform("u_viewport", px); }

void DensityProgram::set_rect(Vec2 origin, Vec2 size) const noexcept {
  program_.set_uniform("u_origin", origin);
  program_.set_uniform("u_size", size);
}

void DensityProgram::set_color(Color color) const noexcept {
  program_.set_uniform("u_color", color);
}

}  // namespace plot::render