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

//go:build linux && loong64

package debug

import (
	"fmt"
	"syscall"
	"unsafe"
)

// GetRegs reads the general-purpose registers of the stopped debuggee.
func (s *Session) GetRegs() (Regs, error) {
	var regs Regs
	_, _, errno := syscall.Syscall6(
		syscall.SYS_PTRACE,
		uintptr(syscall.PTRACE_GETREGS),
		uintptr(s.pid),
		0,
		uintptr(unsafe.Pointer(&regs)),
		0, 0,
	)
	if errno != 0 {
		return regs, fmt.Errorf("debug: PTRACE_GETREGS: %w", errno)
	}
	return regs, nil
}

// SetRegs writes the general-purpose registers of the stopped debuggee.
func (s *Session) SetRegs(regs *Regs) error {
	_, _, errno := syscall.Syscall6(
		syscall.SYS_PTRACE,
		uintptr(syscall.PTRACE_SETREGS),
		uintptr(s.pid),
		0,
		uintptr(unsafe.Pointer(regs)),
		0, 0,
	)
	if errno != 0 {
		return fmt.Errorf("debug: PTRACE_SETREGS: %w", errno)
	}
	return nil
}

// FPRegs holds the LoongArch FP register state (F0-F31).
type FPRegs struct {
	F    [32][16]byte // F0-F31 (128-bit, lower 64 bits used for double)
	FCSR uint32
}

// GetFPRegs retrieves the FP register state.
func (s *Session) GetFPRegs() (FPRegs, error) {
	var fp FPRegs
	_, _, errno := syscall.Syscall6(
		syscall.SYS_PTRACE,
		uintptr(syscall.PTRACE_GETFPREGS),
		uintptr(s.pid),
		0,
		uintptr(unsafe.Pointer(&fp)),
		0, 0,
	)
	if errno != 0 {
		return fp, fmt.Errorf("debug: PTRACE_GETFPREGS: %w", errno)
	}
	return fp, nil
}

// VectorRegs holds the LSX/LASX vector register state (placeholder).
type VectorRegs struct{}

// GetVectorRegs retrieves the vector registers (not yet implemented for loong64).
func (s *Session) GetVectorRegs() (VectorRegs, error) {
	return VectorRegs{}, nil
}