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

#pragma once

#include <cstdint>
#include <string>

namespace udpscope {

/// Everything the command line can say. Defaults are the ones the spec names
/// (200 MB per buffer, 10 ms trigger hold-off) unless the user overrides them.
struct Config {
  std::string server = "127.0.0.1";   ///< IPv4 dotted quad of the stream source.
  std::uint16_t port = 8000;          ///< UDP port (unicast) or TCP port (multicast).
  std::string multicast;              ///< Empty selects unicast.
  std::string interface_addr;         ///< Local IPv4 to join the group on; empty = default route.

  /// Whether `--server` was given. Absent, the application asks which source to open rather
  /// than silently taking the default above -- so this is "did the user choose", not "is
  /// `server` valid". The default stays a usable value for every other path.
  bool server_specified = false;

  /// Size of *each* of the two sample buffers, in megabytes. The application
  /// always allocates two identical buffers (spec item 1).
  double buffer_mb = 200.0;
  /// Whether `--buffer-mb` was given. A stored configuration's buffer size fills in only when the
  /// flag was *absent*: an explicit flag beats a saved setting, and "not asked" is not the same
  /// question as "asked for 200".
  bool buffer_mb_specified = false;

  /// Largest time window the toolbar offers, in seconds. The buffer partition is
  /// sized to hold at least this much time (spec: decimation).
  double max_window_s = 600.0;

  double trigger_holdoff_s = 0.010;
  int recv_buffer_bytes = 8 * 1024 * 1024;

  /// Number of stacked plots (rows) to start with, 1..`RowSet::kMaxRows`. Only the
  /// starting point: rows are added and removed from the layout editor.
  int plots = 1;

  /// Take the plot's time from the packet counter and the declared sample rate rather than
  /// from the stream's own time signal, so arrival and producer-clock jitter cannot move a
  /// sample's x. Absolute stream time is still recorded, for export only (`todo.md` item 2).
  bool relative_time = false;

  /// Whether relative time was *stated* rather than left at its default -- by `--relative-time`, or
  /// by the preferences, which the source chooser can reach before this run is planned. A source's
  /// stored configuration is a statement from an *older* session, so it only fills in the gap.
  bool relative_time_specified = false;

  /// `--capture-packets N`: the ring size of the raw-datagram capture, 1..100000.
  /// 0 means the flag was absent: the capture is off, and the popover button then
  /// uses the 1000-slot default when the user toggles it.
  std::uint32_t capture_packets = 0;

  /// `--open FILE`: a `.npy` an earlier run exported, opened for viewing and analysis instead of a
  /// live source. File mode and source mode are exclusive -- there is no acquisition behind a file,
  /// and the chooser's Waveforms page sets this rather than the connection fields.
  std::string open_waveform;
};

/// Parses argv. On `--help` prints usage to stdout and exits(0); on a bad
/// argument prints a diagnostic to stderr and exits(2).
Config parse_args(int argc, char** argv);

/// Writes the usage text to `out`.
void print_usage(std::FILE* out, const char* argv0);

}  // namespace udpscope