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

//go:build freebsd && arm64

package debug

import (
	"encoding/binary"
	"fmt"
)

func printRegs(regs *Regs, codeBase, funcOff uint64) {
	fmt.Printf("  PC  = %#016x  (func+%#x)\n", regs.PC, regs.PC-codeBase-funcOff)
	fmt.Printf("  SP  = %#016x  FP  = %#016x\n", regs.SP, regs.X29)
	fmt.Printf("  LR  = %#016x\n", regs.X30)
	fmt.Printf("  X0  = %#016x  X1  = %#016x\n", regs.X0, regs.X1)
	fmt.Printf("  X2  = %#016x  X3  = %#016x\n", regs.X2, regs.X3)
	fmt.Printf("  X4  = %#016x  X5  = %#016x\n", regs.X4, regs.X5)
	fmt.Printf("  X6  = %#016x  X7  = %#016x\n", regs.X6, regs.X7)
	fmt.Printf("  X8  = %#016x  X9  = %#016x\n", regs.X8, regs.X9)
	fmt.Printf("  X10 = %#016x  X11 = %#016x\n", regs.X10, regs.X11)
	fmt.Printf("  X12 = %#016x  X13 = %#016x\n", regs.X12, regs.X13)
	fmt.Printf("  X14 = %#016x  X15 = %#016x\n", regs.X14, regs.X15)
	fmt.Printf("  X16 = %#016x  X17 = %#016x\n", regs.X16, regs.X17)
	fmt.Printf("  X18 = %#016x  X19 = %#016x\n", regs.X18, regs.X19)
	fmt.Printf("  X20 = %#016x  X21 = %#016x\n", regs.X20, regs.X21)
	fmt.Printf("  X22 = %#016x  X23 = %#016x\n", regs.X22, regs.X23)
	fmt.Printf("  X24 = %#016x  X25 = %#016x\n", regs.X24, regs.X25)
	fmt.Printf("  X26 = %#016x  X27 = %#016x\n", regs.X26, regs.X27)
	fmt.Printf("  X28 = %#016x  PSTATE = %#x\n", regs.X28, regs.PSTATE)
}

func printVectorRegs(v *VectorRegs) {
	fmt.Println("\n  Vector registers (V0-V31):")
	for i := 0; i < 32; i += 2 {
		fmt.Printf("  V%-2d  = %016x%016x\n", i, binary.LittleEndian.Uint64(v.V[i][8:16]), binary.LittleEndian.Uint64(v.V[i][0:8]))
		fmt.Printf("  V%-2d  = %016x%016x\n", i+1, binary.LittleEndian.Uint64(v.V[i+1][8:16]), binary.LittleEndian.Uint64(v.V[i+1][0:8]))
	}
}

// SetReg modifies a register value in the debuggee.
func (s *Session) SetReg(name string, value uint64) error {
	regs, err := s.GetRegs()
	if err != nil {
		return err
	}
	switch name {
	case "x0":
		regs.X0 = value
	case "x1":
		regs.X1 = value
	case "x2":
		regs.X2 = value
	case "x3":
		regs.X3 = value
	case "x4":
		regs.X4 = value
	case "x5":
		regs.X5 = value
	case "x6":
		regs.X6 = value
	case "x7":
		regs.X7 = value
	case "x8":
		regs.X8 = value
	case "x9":
		regs.X9 = value
	case "x10":
		regs.X10 = value
	case "x11":
		regs.X11 = value
	case "x12":
		regs.X12 = value
	case "x13":
		regs.X13 = value
	case "x14":
		regs.X14 = value
	case "x15":
		regs.X15 = value
	case "x16":
		regs.X16 = value
	case "x17":
		regs.X17 = value
	case "x18":
		regs.X18 = value
	case "x19":
		regs.X19 = value
	case "x20":
		regs.X20 = value
	case "x21":
		regs.X21 = value
	case "x22":
		regs.X22 = value
	case "x23":
		regs.X23 = value
	case "x24":
		regs.X24 = value
	case "x25":
		regs.X25 = value
	case "x26":
		regs.X26 = value
	case "x27":
		regs.X27 = value
	case "x28":
		regs.X28 = value
	case "x29", "fp":
		regs.X29 = value
	case "x30", "lr":
		regs.X30 = value
	case "sp":
		regs.SP = value
	case "pc":
		regs.PC = value
	default:
		return fmt.Errorf("debug: unknown register %q", name)
	}
	return s.SetRegs(&regs)
}

// archReturnAddr reads the return address from LR (arm64 convention).
func archReturnAddr(s *Session, regs *Regs) (uint64, error) {
	return regs.X30, nil
}

// archSPLabel returns the SP register name for display.
func archSPLabel() string { return "SP" }