// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: BSD-3-Clause

//go:build freebsd && riscv64

package debug

import "fmt"

// The architecture has hardware watchpoint triggers, but FreeBSD exposes
// no PT_GETDBREGS request for riscv64, so there is no supported way to arm
// one: the watchpoint layer is honestly empty here.

// WatchpointType selects what triggers the watchpoint.
type WatchpointType int

const (
	WatchWrite WatchpointType = 1 // trigger on write
	WatchRead  WatchpointType = 3 // trigger on read or write
)

// maxWatchpoints reports the number of hardware watchpoint slots the
// platform provides: FreeBSD exposes none for riscv64.
func maxWatchpoints() int { return 0 }

// archStopTrace classifies a TRAP_TRACE stop; with no watchpoint layer a
// trace stop is always a completed single step.
func archStopTrace(s *Session, siAddr uint64) (StopReason, uint64) {
	return StopSingleStep, 0
}

// FindFreeWatchpointSlot returns -1: no slots exist.
func (s *Session) FindFreeWatchpointSlot() int { return -1 }

// IsWatchpointSlotUsed reports whether slot currently holds a watchpoint.
func (s *Session) IsWatchpointSlotUsed(slot int) bool { return false }

// SetWatchpoint is unsupported: FreeBSD exposes no debug register request
// for riscv64.
func (s *Session) SetWatchpoint(slot int, addr uint64, typ WatchpointType, size int) error {
	return fmt.Errorf("debug: hardware watchpoints are not supported on freebsd/riscv64")
}

// ClearWatchpoint is unsupported for the same reason.
func (s *Session) ClearWatchpoint(slot int) error {
	return fmt.Errorf("debug: hardware watchpoints are not supported on freebsd/riscv64")
}

// ClearAllWatchpoints is a no-op: no watchpoint can be armed.
func (s *Session) ClearAllWatchpoints() error { return nil }