/* radare - LGPL3 - Copyright 2017 - maijin */

#include <string.h>
#include <r_types.h>
#include <r_lib.h>
#include <r_asm.h>
#include <r_anal.h>

static int chip8_anop(RAnal *anal, RAnalOp *op, ut64 addr, const ut8 *data, int len) {
	memset (op, '\0', sizeof (RAnalOp));
	ut16 opcode = r_read_be16 (data);
//	uint8_t x = (opcode >> 8) & 0x0F;
//	uint8_t y = (opcode >> 4) & 0x0F;
	uint8_t nibble = opcode & 0x0F;
	uint16_t nnn = opcode & 0x0FFF;
	uint8_t kk = opcode & 0xFF;
	op->size = 2;
	op->addr = addr;
	switch (opcode & 0xF000) {
	case 0x0000:
		if (opcode == 0x00E0) {
			op->type = R_ANAL_OP_TYPE_UNK;
		} else if (opcode == 0x00EE) {
			op->type = R_ANAL_OP_TYPE_UNK;
		} else if (opcode == 0x00C0) {
			op->type = R_ANAL_OP_TYPE_UNK;
		} else if (opcode == 0x00FB) {
			op->type = R_ANAL_OP_TYPE_UNK;
		} else if (opcode == 0x00FC) {
			op->type = R_ANAL_OP_TYPE_UNK;
		} else if (opcode == 0x00FD) {
			op->type = R_ANAL_OP_TYPE_UNK;
		} else if (opcode == 0x00FE) {
			op->type = R_ANAL_OP_TYPE_UNK;
		} else if (opcode == 0x00FF) {
			op->type = R_ANAL_OP_TYPE_UNK;
		}
		break;
	case 0x1000:
		op->type = R_ANAL_OP_TYPE_JMP;
		op->jump = nnn;
		op->fail = addr + op->size;
		break;
	case 0x2000:
		op->type = R_ANAL_OP_TYPE_CALL;
		op->jump = nnn;
		op->fail = addr + op->size;
		break;
	case 0x3000:
		r_meta_set_string (anal, R_META_TYPE_COMMENT, addr, "KEYPAD");
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0x4000:
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0x5000:
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0x6000:
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0x7000:
		op->type = R_ANAL_OP_TYPE_ADD;
		break;
	case 0x8000: {
		switch (nibble) {
		case 0x0:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x1:
			op->type = R_ANAL_OP_TYPE_OR;
			break;
		case 0x2:
			op->type = R_ANAL_OP_TYPE_AND;
			break;
		case 0x3:
			op->type = R_ANAL_OP_TYPE_XOR;
			break;
		case 0x4:
			op->type = R_ANAL_OP_TYPE_ADD;
			break;
		case 0x5:
			op->type = R_ANAL_OP_TYPE_SUB;
			break;
		case 0x6:
			op->type = R_ANAL_OP_TYPE_SHR;
			break;
		case 0x7:
			op->type = R_ANAL_OP_TYPE_SUB;
			break;
		case 0xE:
			op->type = R_ANAL_OP_TYPE_SHL;
			break;
		}
	} break;
	case 0x9000:
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0xA000:
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0xB000:
		op->type = R_ANAL_OP_TYPE_JMP;
		op->jump = nnn;
		op->fail = addr + op->size;
		break;
	case 0xC000:
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0xD000:
		op->type = R_ANAL_OP_TYPE_UNK;
		break;
	case 0xE000: {
		if (kk == 0x9E) {
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		} else if (kk == 0xA1) {
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		}
	} break;
	case 0xF000: {
		switch (kk) {
		case 0x07:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x0A:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x15:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x18:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x1E:
			op->type = R_ANAL_OP_TYPE_ADD;
			break;
		case 0x29:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x33:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x55:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x65:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x30:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x75:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		case 0x85:
			op->type = R_ANAL_OP_TYPE_UNK;
			break;
		}
	} break;
	}
	return op->size;
}

RAnalPlugin r_anal_plugin_chip8 = {
	.name = "chip8",
	.desc = "CHIP8 analysis plugin",
	.license = "LGPL3",
	.arch = "chip8",
	.bits = 32,
	.op = &chip8_anop,
};

#ifndef CORELIB
RLibStruct radare_plugin = {
	.type = R_LIB_TYPE_ANAL,
	.data = &r_anal_plugin_chip8,
	.version = R2_VERSION
};
#endif