#include "../includes/opcodes.h"
#include <stdlib.h>
#include <string.h>

Instruction instructions[OPCODECOUNT] = {
    { "copy", COPY, Reg | Address, Reg | Constant | Address },
    { "add", ADD, Reg, Reg | Constant },
    { "sub", SUB, Reg, Reg | Constant },
    { "jz", JZ, Address, None },
    { "int", INT, Constant, None },
    { "yld", YLD, None, None },
    { "ret", RET, None, None },
    { "cmp", CMP, Reg, Reg | Constant },
    { "in", IN, Constant | Reg, None},
    { "out", OUT, None, None},
    { "nop", NOP, None, None}
};

/*
    NOP  - 0000 0000 NOP
    JZ   - 0000 0001 JZ Address
    INT  - 0000 0010 INT Constant
    YLD  - 0000 0011 YLD
    RET  - 0000 0100 RET
    CALL - 0000 0101 CALL Address
    JMP  - 0000 0110 JMP Address

    COPY - 0010 0XXX COPY REG, REG
         - 0010 1XXX COPY REG, Constant    
         - 0011 0XXX COPY REG, Address
         - 1010 0XXX COPY Address, REG
         - 1010 1XXX COPY Address, Constant
         - 1011 0XXX COPY Address, Address

    ADD  - 0100 0XXX ADD REG, REG
         - 0100 1XXX ADD REG, Constant
    SUB  - 0110 0XXX SUB REG, REG
         - 0110 1XXX SUB REG, Constant
    CMP  - 1000 0XXX CMP REG, REG
         - 1000 1XXX CMP REG, Constant
         - 1001 0XXX CMP REG, Address

    OUT  - 1111 1XXX OUT REG
*/
//COPY      X01X XXXX
//ADD       010X XXXX
//SUB       011X XXXX
//CMP       100X XXXX
//REG       XXX0 0XXX
//Constant  XXX0 1XXX
//Address   XXX1 0XXX
//R1        XXXX X000 -> XXXX X111 (R1 to R8)

Register registers[REGISTERCOUNT] = {
    { "r1", R1 },
    { "r2", R2 },
    { "r3", R3 },
    { "r4", R4 },
    { "r5", R5 },
    { "r6", R6 },
    { "r7", R7 },
    { "r8", R8 }
};

const Instruction* GetOpcodeDetails(TokenType type) {
    for(int i = 0; i < OPCODECOUNT; i++) {
        if (instructions[i].op == type) return &instructions[i];
    }

    return NULL;
}

int IsOpcode(const char* text, TokenType* opcode) {
    if (!text) return 0;

    for(int i = 0; i < OPCODECOUNT; i++) {
        if (strcmp(instructions[i].lexeme, text) == 0) {
            if (opcode) *opcode = instructions[i].op;
            return 1;
        }
    }

    return 0;
}

int IsRegister(const char* text, TokenType* reg) {
    if (!text) return 0;

    for(int i = 0; i < REGISTERCOUNT; i++) {
        if (strcmp(registers[i].lexeme, text) == 0)  {
            *reg = registers[i].type;
            return 1;
        }
    }

    return 0;
}