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

#pragma once
#include <vector>

#include <plot/core/types.hpp>
#include <plot/data/series.hpp>

namespace plot::data {

/// Series over a uniform-dx sample vector.
///
/// The vector is taken by value and owned from then on, so the caller cannot
/// mutate the samples behind the series' back; the store changes only through
/// reset() (a whole new vector) or commit(), which rebuilds the pyramid and the
/// cached bounds for whatever y_ currently holds.
class ArraySeries final : public Series {
 public:
  ArraySeries(std::vector<f32> y, f64 x0, f64 dx);
  /// Replaces samples and grid, then rebuilds derived state (== commit()).
  void reset(std::vector<f32> y, f64 x0, f64 dx);
  /// Rebuilds the pyramid and cached bounds from y_ as it stands now.
  void commit();
  /// Appends one sample incrementally: the pyramid folds it (`append`, amortised
  /// O(1)) and the cached bounds extend in O(1), NaN-aware, instead of commit()
  /// rebuilding the whole store. The wholesale path stays `commit()`.
  void push(f32 y);

  u64 size() const override;
  f64 x0() const override;
  f64 dx() const override;
  Range x_bounds() const override;
  Range y_bounds() const override;
  const MinMaxPyramid& pyramid() const override;
  void gather(u32 level, u64 begin, u64 end, std::vector<f32>& out_xy,
              GatherMode mode = GatherMode::Envelope) const override;

 protected:
  void copy_raw(u64 begin, u64 end, f32* out) const override;

 private:
  std::vector<f32> y_;
  f64 x0_ = 0.0;
  f64 dx_ = 1.0;
  MinMaxPyramid pyramid_;
  Range x_bounds_{};
  Range y_bounds_{};
  /// False until a finite sample has been seen: `y_bounds_` is then a
  /// placeholder (zero-span), not an aggregate, and the next finite sample
  /// seeds it. This is what makes push()'s incremental extension and commit()'s
  /// rebuild agree on a window that holds non-finite samples.
  bool y_has_finite_ = false;
};

}  // namespace plot::data