#ifndef INSTRUCTIONS_H
#define INSTRUCTIONS_H

// Prefixes
// Prefix groups are mutually exclusive

// Prefix group 1
#define PREFIX_LOCK  0xf0
#define PREFIX_REPNE 0xf2
#define PREFIX_REPNZ PREFIX_REPNE
#define PREFIX_REP   0xf3
#define PREFIX_REPE  PREFIX_REP
#define PREFIX_REPZ  PREFIX_REP

// Prefix group 2
#define PREFIX_OVERRIDE_SEGMENT_CS 0x2e
#define PREFIX_OVERRIDE_SEGMENT_SS 0x36
#define PREFIX_OVERRIDE_SEGMENT_DS 0x3e
#define PREFIX_OVERRIDE_SEGMENT_ES 0x26
#define PREFIX_OVERRIDE_SEGMENT_FS 0x64
#define PREFIX_OVERRIDE_SEGMENT_GS 0x65
#define PREFIX_BRANCH_NOT_TAKEN    PREFIX_OVERRIDE_SEGMENT_CS
#define PREFIX_BRANCH_TAKEN        PREFIX_OVERRIDE_SEGMENT_DS

// Prefix group 3
#define PREFIX_OVERRIDE_OPSIZE 0x66

// Prefix group 4
#define PREFIX_OVERRIDE_ADDRESSSIZE 0x67

// Instructions
// Move double-word immediate
#define MOVBI(reg, imm) (0xb0 + reg), (imm & 0xff)
#define MOVWI(reg, imm)                                                        \
  (0xb8 + reg), (imm & 0xff), ((imm >> 8) & 0xff), ((imm >> 16) & 0xff)
#define MOVDI(reg, imm)                                                        \
  (0xb8 + reg), (imm & 0xff), ((imm >> 8) & 0xff), ((imm >> 16) & 0xff),       \
    ((imm >> 24) & 0xff)
// TODO replace 0x48 with encoding,
// | 0 1 0 0 | W R X B |
//
// 0 1 0 0 -- fixed pattern
// W       -- Set to use 64-bit operands,
// R       -- extension to MODRM.reg field, registers
// X       -- extension to SIB.index field, 64-bit addressing
// B       -- extension to MODRM.rm or SIB.base field, 64-bit addressing
#define MOVABS(reg, imm) 0x48, MOVD(reg, imm)
#define MOVQ(reg, imm)   0x48, 89 c8

#define ADD
#define CALL
#define CMP
#define DEC
#define DIV
#define HLT
#define IDIV
#define IMUL
#define INC
#define INT
#define INTO
#define IRET
#define JNZ
#define JMP
#define LEA
#define POP
#define PUSH
#define RET
#define RETN
#define SUB
#define XOR

#define SYSCALL 0x0f, 0x05

#define REX(mode) (0b01000000 | mode)

#endif