// Copyright 2026 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#pragma once

#include <optional>
#include <string_view>

#include "Common/CommonTypes.h"

// How long StarletBootstrapProbe runs an image: whole slices of SLICE_CYCLES ARM cycles, between
// which it checks for a fault, a panic or a terminal trace line. --cycles <n> sets the budget;
// without it, the probe runs DEFAULT_CYCLES, as it always has. StarOS's EXP-003 images hash MEM2
// and time series of operations, which take more than that (StarOS
// experiments/proposals/mmu-console.md, P-7 and P-8).
namespace StarletBootstrapProbe
{
constexpr u32 SLICE_CYCLES = 4096;
constexpr u64 DEFAULT_CYCLES = 512 * SLICE_CYCLES;
// 2^30 cycles: 262,144 slices.
constexpr u64 MAX_CYCLES = u64{1} << 30;

// The budget --cycles asks for: a decimal number of cycles, a whole number of slices, from one
// slice to MAX_CYCLES. Anything else is refused (nullopt), never rounded.
inline std::optional<u64> ParseCycles(std::string_view text)
{
  // Twelve digits cannot overflow a u64; MAX_CYCLES has ten.
  if (text.empty() || text.size() > 12)
    return std::nullopt;
  u64 value = 0;
  for (const char digit : text)
  {
    if (digit < '0' || digit > '9')
      return std::nullopt;
    value = value * 10 + static_cast<u64>(digit - '0');
  }
  if (value == 0 || value % SLICE_CYCLES != 0 || value > MAX_CYCLES)
    return std::nullopt;
  return value;
}
}  // namespace StarletBootstrapProbe