#pragma once

#include <string>
#include <string_view>
#include <vector>

#include "app.hh"


namespace pg {

class Input final : App {
 public:
  class Data;

  static Input& instance() noexcept { return instance_; }

  Input() = default;
  Input(const Input&) = delete;
  Input(Input&&) = delete;
  Input& operator=(const Input&) = delete;
  Input& operator=(Input&&) = delete;

  size_t Add(Data*) noexcept;
  void Update() noexcept override;

  Data* slots(size_t idx) noexcept {
    return idx < slots_.size()? slots_[idx]: nullptr;
  }

 private:
  static Input instance_;

  std::vector<Data*> slots_;
};

class Input::Data {
 public:
  struct Frame {
   public:
    size_t w, h;
    const uint8_t* rgba;
  };

  Data() = delete;
  Data(std::string_view name) noexcept : name_(name) {
    idx_ = Input::instance().Add(this);
  }
  virtual ~Data() = default;
  Data(const Data&) = delete;
  Data(Data&&) = delete;
  Data& operator=(const Data&) = delete;
  Data& operator=(Data&&) = delete;

  virtual Frame Fetch(size_t) noexcept = 0;
  virtual size_t frames() noexcept = 0;

  size_t index() const noexcept { return idx_; }

  std::vector<float> FetchSamples(
      size_t st, size_t dur, float x, float y, size_t offset) noexcept;

  const std::string& name() const noexcept { return name_; }

 private:
  std::string name_;

  size_t idx_;
};

}  // namespace pg