// SPDX-FileCopyrightText: 2009-2019 earada <pkedurat@gmail.com>
// SPDX-FileCopyrightText: 2009-2019 pancake <pancake@nopcode.org>
// SPDX-FileCopyrightText: 2009-2019 h4ng3r
// SPDX-License-Identifier: LGPL-3.0-only

#include <stdio.h>
#include <string.h>

#include <rz_types.h>
#include <rz_lib.h>
#include <rz_asm.h>

#include <dalvik/opcode.h>

static int dalvik_disassemble(RzAsm *a, RzAsmOp *op, const ut8 *buf, int len) {
	rz_return_val_if_fail(a && op && buf && len > 0, -1);

	int vA, vB, vC, vD, vE, vF, vG, vH, payload = 0, i = (int)buf[0];
	int size = dalvik_opcodes[i].len;
	char str[1024], *strasm = NULL;
	ut64 offset = 0;
	char *flag_str = NULL;
	a->dataalign = 2;

	if (buf[0] == 0x00) { /* nop */
		if (len < 2) {
			return -1;
		}
		switch (buf[1]) {
		case 0x01: /* packed-switch-payload */
			// ushort size
			// int first_key
			// int[size] = relative offsets
			{
				ut16 array_size = buf[2] | (buf[3] << 8);
				int first_key = buf[4] | (buf[5] << 8) | (buf[6] << 16) | (buf[7] << 24);
				rz_asm_op_setf_asm(op, "packed-switch-payload %d, %d", array_size, first_key);
				size = 8;
				payload = 2 * (array_size * 2);
				len = 0;
			}
			break;
		case 0x02: /* sparse-switch-payload */
			// ushort size
			// int[size] keys
			// int[size] relative offsets
			{
				ut16 array_size = buf[2] | (buf[3] << 8);
				rz_asm_op_setf_asm(op, "sparse-switch-payload %d", array_size);
				size = 4;
				payload = 2 * (array_size * 4);
				len = 0;
			}
			break;
		case 0x03: /* fill-array-data-payload */
			// element_width = 2 bytes ushort little endian
			// size = 4 bytes uint
			// ([size*element_width+1)/2)+4
			if (len > 7) {
				ut16 elem_width = buf[2] | (buf[3] << 8);
				ut32 array_size = buf[4] | (buf[5] << 8) | (buf[6] << 16) | (buf[7] << 24);
				rz_asm_op_setf_asm(op, "fill-array-data-payload %d, %d", elem_width, array_size);
				payload = array_size * elem_width;
			}
			size = 8;
			len = 0;
			break;
		default:
			rz_asm_op_set_asm(op, "invalid");
			break;
		}
	}

	strasm = NULL;
	if (size <= len) {
		strasm = rz_str_dup(dalvik_opcodes[i].name);
		size = dalvik_opcodes[i].len;
		switch (dalvik_opcodes[i].fmt) {
		case fmtop: break;
		case fmtopvAvB:
			vA = buf[1] & 0x0f;
			vB = (buf[1] & 0xf0) >> 4;
			rz_strf(str, " v%i, v%i", vA, vB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAvBBBB:
			vA = (int)buf[1];
			vB = (buf[3] << 8) | buf[2];
			rz_strf(str, " v%i, v%i", vA, vB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAAAvBBBB: // buf[1] seems useless :/
			vA = (buf[3] << 8) | buf[2];
			vB = (buf[5] << 8) | buf[4];
			rz_strf(str, " v%i, v%i", vA, vB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAA:
			vA = (int)buf[1];
			rz_strf(str, " v%i", vA);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAcB:
			vA = buf[1] & 0x0f;
			vB = (buf[1] & 0xf0) >> 4;
			rz_strf(str, " v%i, %#x", vA, vB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAcBBBB:
			vA = (int)buf[1];
			{
				short sB = (buf[3] << 8) | buf[2];
				rz_strf(str, " v%i, %#04hx", vA, sB);
				strasm = rz_str_append(strasm, str);
			}
			break;
		case fmtopvAAcBBBBBBBB:
			vA = (int)buf[1];
			vB = buf[2] | (buf[3] << 8) | (buf[4] << 16) | (buf[5] << 24);
			if (buf[0] == 0x17) { // const-wide/32
				rz_strf(str, " v%i:v%i, 0x%08x", vA, vA + 1, vB);
			} else { // const
				rz_strf(str, " v%i, 0x%08x", vA, vB);
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAcBBBB0000:
			vA = (int)buf[1];
			// vB = 0|(buf[3]<<16)|(buf[2]<<24);
			vB = 0 | (buf[2] << 16) | (buf[3] << 24);
			if (buf[0] == 0x19) { // const-wide/high16
				rz_strf(str, " v%i:v%i, 0x%08x", vA, vA + 1, vB);
			} else {
				rz_strf(str, " v%i, 0x%08x", vA, vB);
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAcBBBBBBBBBBBBBBBB:
			vA = (int)buf[1];
			ut64 lB = (ut64)buf[2] | ((ut64)buf[3] << 8) |
				((ut64)buf[4] << 16) | ((ut64)buf[5] << 24) |
				((ut64)buf[6] << 32) | ((ut64)buf[7] << 40) |
				((ut64)(buf[8] & 0xff) << 48) | ((ut64)(buf[9] & 0xff) << 56);
			rz_strf(str, " v%i:v%i, 0x%" PFMT64x, vA, vA + 1, lB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAvBBvCC:
			vA = (int)buf[1];
			vB = (int)buf[2];
			vC = (int)buf[3];
			rz_strf(str, " v%i, v%i, v%i", vA, vB, vC);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAvBBcCC:
			vA = (int)buf[1];
			vB = (int)buf[2];
			vC = (int)buf[3];
			rz_strf(str, " v%i, v%i, %#x", vA, vB, vC);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAvBcCCCC:
			vA = buf[1] & 0x0f;
			vB = (buf[1] & 0xf0) >> 4;
			vC = (buf[3] << 8) | buf[2];
			rz_strf(str, " v%i, v%i, %#x", vA, vB, vC);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoppAA:
			vA = (signed char)buf[1];
			// snprintf (str, sizeof (str), " %i", vA*2); // vA : word -> byte
			rz_strf(str, " 0x%08" PFMT64x, a->pc + (vA * 2)); // vA : word -> byte
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoppAAAA:
			vA = (short)(buf[3] << 8 | buf[2]);
			rz_strf(str, " 0x%08" PFMT64x, a->pc + (vA * 2)); // vA : word -> byte
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAApBBBB: // if-*z
			vA = (int)buf[1];
			vB = (int)(buf[3] << 8 | buf[2]);
			// snprintf (str, sizeof (str), " v%i, %i", vA, vB);
			rz_strf(str, " v%i, 0x%08" PFMT64x, vA, a->pc + (vB * 2));
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoppAAAAAAAA:
			vA = (int)(buf[2] | (buf[3] << 8) | (buf[4] << 16) | (buf[5] << 24));
			// snprintf (str, sizeof (str), " %#08x", vA*2); // vA: word -> byte
			rz_strf(str, " 0x%08" PFMT64x, a->pc + (vA * 2)); // vA : word -> byte
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAvBpCCCC: // if-*
			vA = buf[1] & 0x0f;
			vB = (buf[1] & 0xf0) >> 4;
			vC = (int)(buf[3] << 8 | buf[2]);
			// snprintf (str, sizeof (str), " v%i, v%i, %i", vA, vB, vC);
			rz_strf(str, " v%i, v%i, 0x%08" PFMT64x, vA, vB, a->pc + (vC * 2));
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAApBBBBBBBB:
			vA = (int)buf[1];
			vB = (short)(buf[2] | (buf[3] << 8) | (buf[4] << 16) | (buf[5] << 24));
			rz_strf(str, " v%i, 0x%08" PFMT64x, vA, a->pc + (vB * 2) + 8);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoptinlineI:
			vA = (int)(buf[1] & 0x0f);
			vB = (buf[3] << 8) | buf[2];
			*str = 0;
			switch (vA) {
			case 1:
				rz_strf(str, " {v%i}", buf[4] & 0x0f);
				break;
			case 2:
				rz_strf(str, " {v%i, v%i}", buf[4] & 0x0f, (buf[4] & 0xf0) >> 4);
				break;
			case 3:
				rz_strf(str, " {v%i, v%i, v%i}", buf[4] & 0x0f, (buf[4] & 0xf0) >> 4, buf[5] & 0x0f);
				break;
			case 4:
				rz_strf(str, " {v%i, v%i, v%i, v%i}", buf[4] & 0x0f,
					(buf[4] & 0xf0) >> 4, buf[5] & 0x0f, (buf[5] & 0xf0) >> 4);
				break;
			default:
				rz_strf(str, " {}");
			}
			strasm = rz_str_append(strasm, str);
			rz_strf(str, ", [%04x]", vB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoptinlineIR:
		case fmtoptinvokeVSR:
			vA = (int)buf[1];
			vB = (buf[3] << 8) | buf[2];
			vC = (buf[5] << 8) | buf[4];
			rz_strf(str, " {v%i..v%i}, [%04x]", vC, vC + vA - 1, vB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoptinvokeVS:
			vA = (int)(buf[1] & 0xf0) >> 4;
			vB = (buf[3] << 8) | buf[2];
			switch (vA) {
			case 1:
				rz_strf(str, " {v%i}", buf[4] & 0x0f);
				break;
			case 2:
				rz_strf(str, " {v%i, v%i}", buf[4] & 0x0f, (buf[4] & 0xf0) >> 4);
				break;
			case 3:
				rz_strf(str, " {v%i, v%i, v%i}", buf[4] & 0x0f,
					(buf[4] & 0xf0) >> 4, buf[5] & 0x0f);
				break;
			case 4:
				rz_strf(str, " {v%i, v%i, v%i, v%i}", buf[4] & 0x0f,
					(buf[4] & 0xf0) >> 4, buf[5] & 0x0f, (buf[5] & 0xf0) >> 4);
				break;
			default:
				rz_strf(str, " {}");
				break;
			}
			strasm = rz_str_append(strasm, str);
			rz_strf(str, ", [%04x]", vB);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAtBBBB: // "sput-*"
			vA = (int)buf[1];
			vB = (buf[3] << 8) | buf[2];
			if (buf[0] == 0x1a) {
				offset = RZ_ASM_GET_OFFSET(a, 's', vB);
				if (offset == UT64_MAX) {
					rz_strf(str, " v%i, string+%i", vA, vB);
				} else {
					rz_strf(str, " v%i, 0x%" PFMT64x, vA, offset);
				}
			} else if (buf[0] == 0x1c || buf[0] == 0x1f || buf[0] == 0x22) {
				flag_str = RZ_ASM_GET_NAME(a, 'c', vB);
				if (!flag_str) {
					rz_strf(str, " v%i, class+%i", vA, vB);
				} else {
					rz_strf(str, " v%i, %s", vA, flag_str);
				}
			} else {
				flag_str = RZ_ASM_GET_NAME(a, 'f', vB);
				if (!flag_str) {
					rz_strf(str, " v%i, field+%i", vA, vB);
				} else {
					rz_strf(str, " v%i, %s", vA, flag_str);
				}
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoptopvAvBoCCCC:
			vA = (buf[1] & 0x0f);
			vB = (buf[1] & 0xf0) >> 4;
			vC = (buf[3] << 8) | buf[2];
			offset = RZ_ASM_GET_OFFSET(a, 'o', vC);
			if (offset == UT64_MAX) {
				rz_strf(str, " v%i, v%i, [obj+%04x]", vA, vB, vC);
			} else {
				rz_strf(str, " v%i, v%i, [0x%" PFMT64x "]", vA, vB, offset);
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopAAtBBBB:
			vA = (int)buf[1];
			vB = (buf[3] << 8) | buf[2];
			offset = RZ_ASM_GET_OFFSET(a, 't', vB);
			if (offset == UT64_MAX) {
				rz_strf(str, " v%i, thing+%i", vA, vB);
			} else {
				rz_strf(str, " v%i, 0x%" PFMT64x, vA, offset);
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAvBtCCCC:
			vA = (buf[1] & 0x0f);
			vB = (buf[1] & 0xf0) >> 4;
			vC = (buf[3] << 8) | buf[2];
			if (buf[0] == 0x20 || buf[0] == 0x23) { // instance-of & new-array
				flag_str = RZ_ASM_GET_NAME(a, 'c', vC);
				if (RZ_STR_ISNOTEMPTY(flag_str)) {
					rz_strf(str, " v%i, v%i, %s", vA, vB, flag_str);
				} else {
					rz_strf(str, " v%i, v%i, class+%i", vA, vB, vC);
				}
			} else {
				flag_str = RZ_ASM_GET_NAME(a, 'f', vC);
				if (RZ_STR_ISNOTEMPTY(flag_str)) {
					rz_strf(str, " v%i, v%i, %s", vA, vB, flag_str);
				} else {
					rz_strf(str, " v%i, v%i, field+%i", vA, vB, vC);
				}
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvAAtBBBBBBBB:
			vA = (int)buf[1];
			vB = (int)(buf[5] | (buf[4] << 8) | (buf[3] << 16) | (buf[2] << 24));
			offset = RZ_ASM_GET_OFFSET(a, 's', vB);
			if (offset == UT64_MAX) {
				rz_strf(str, " v%i, string+%i", vA, vB);
			} else {
				rz_strf(str, " v%i, 0x%" PFMT64x, vA, offset);
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvCCCCmBBBB:
			vA = (int)buf[1];
			vB = (buf[3] << 8) | buf[2];
			vC = (buf[5] << 8) | buf[4];
			if (buf[0] == 0x25) { // filled-new-array/range
				flag_str = RZ_ASM_GET_NAME(a, 'c', vB);
				if (RZ_STR_ISNOTEMPTY(flag_str)) {
					rz_strf(str, " {v%i..v%i}, %s", vC, vC + vA - 1, flag_str);
				} else {
					rz_strf(str, " {v%i..v%i}, class+%i", vC, vC + vA - 1, vB);
				}
			} else if (buf[0] == 0xfd) { // invoke-custom/range
				flag_str = RZ_ASM_GET_NAME(a, 's', vB);
				if (RZ_STR_ISNOTEMPTY(flag_str)) {
					rz_strf(str, " {v%i..v%i}, %s", vC, vC + vA - 1, flag_str);
				} else {
					rz_strf(str, " {v%i..v%i}, call_site+%i", vC, vC + vA - 1, vB);
				}
			} else {
				flag_str = RZ_ASM_GET_NAME(a, 'm', vB);
				if (RZ_STR_ISNOTEMPTY(flag_str)) {
					rz_strf(str, " {v%i..v%i}, %s", vC, vC + vA - 1, flag_str);
				} else {
					rz_strf(str, " {v%i..v%i}, method+%i", vC, vC + vA - 1, vB);
				}
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtopvXtBBBB:
			vA = (int)(buf[1] & 0xf0) >> 4;
			vB = (buf[3] << 8) | buf[2];
			switch (vA) {
			case 1:
				rz_strf(str, " {v%i}", buf[4] & 0x0f);
				break;
			case 2:
				rz_strf(str, " {v%i, v%i}", buf[4] & 0x0f, (buf[4] & 0xf0) >> 4);
				break;
			case 3:
				rz_strf(str, " {v%i, v%i, v%i}", buf[4] & 0x0f,
					(buf[4] & 0xf0) >> 4, buf[5] & 0x0f);
				break;
			case 4:
				rz_strf(str, " {v%i, v%i, v%i, v%i}", buf[4] & 0x0f,
					(buf[4] & 0xf0) >> 4, buf[5] & 0x0f, (buf[5] & 0xf0) >> 4);
				break;
			case 5:
				rz_strf(str, " {v%i, v%i, v%i, v%i, v%i}", buf[4] & 0x0f,
					(buf[4] & 0xf0) >> 4, buf[5] & 0x0f, (buf[5] & 0xf0) >> 4, buf[1] & 0x0f); // TOODO: recheck this
				break;
			default:
				rz_strf(str, " {}");
			}
			strasm = rz_str_append(strasm, str);
			if (buf[0] == 0x24) { // filled-new-array
				flag_str = RZ_ASM_GET_NAME(a, 'c', vB);
				if (RZ_STR_ISEMPTY(flag_str)) {
					rz_strf(str, ", class+%i", vB);
				} else {
					rz_strf(str, ", %s", flag_str);
				}
			} else if (buf[0] == 0xfc) { // invoke-custom
				flag_str = RZ_ASM_GET_NAME(a, 's', vB);
				if (RZ_STR_ISEMPTY(flag_str)) {
					rz_strf(str, ", call_site+%i", vB);
				} else {
					rz_strf(str, ", %s", flag_str);
				}
			} else { // invoke-kind
				flag_str = RZ_ASM_GET_NAME(a, 'm', vB);
				if (RZ_STR_ISNOTEMPTY(flag_str)) {
					rz_strf(str, ", %s", flag_str);
				} else {
					rz_strf(str, ", method+%i", vB);
				}
			}
			free(flag_str);
			strasm = rz_str_append(strasm, str);
			break;
		case fmtop45CC:
			vA = (buf[1] & 0xf0) >> 4;
			vG = (buf[1] & 0x0f);
			vB = (buf[3] << 8) | buf[2];
			vD = (buf[4] & 0xf0) >> 4;
			vC = (buf[4] & 0x0f);
			vF = (buf[5] & 0xf0) >> 4;
			vE = (buf[5] & 0x0f);
			vH = (buf[7] << 8) | buf[6];

			switch (vA) {
			case 1:
				rz_strf(str, " {v%d}", vC);
				break;
			case 2:
				rz_strf(str, " {v%d, v%d}", vC, vD);
				break;
			case 3:
				rz_strf(str, " {v%d, v%d, v%d}", vC, vD, vE);
				break;
			case 4:
				rz_strf(str, " {v%d, v%d, v%d, v%d}", vC, vD, vE, vF);
				break;
			case 5:
				rz_strf(str, " {v%d, v%d, v%d, v%d, v%d}", vC, vD, vE, vF, vG);
				break;
			default:
				rz_strf(str, " %d", vC);
				break;
			}
			strasm = rz_str_append(strasm, str);

			flag_str = RZ_ASM_GET_NAME(a, 'm', vB);
			if (RZ_STR_ISNOTEMPTY(flag_str)) {
				strasm = rz_str_appendf(strasm, ", %s", flag_str);
			} else {
				strasm = rz_str_appendf(strasm, ", method+%i", vB);
			}

			flag_str = RZ_ASM_GET_NAME(a, 'p', vH);
			if (RZ_STR_ISNOTEMPTY(flag_str)) {
				strasm = rz_str_appendf(strasm, ", %s", flag_str);
			} else {
				strasm = rz_str_appendf(strasm, ", proto+%i", vH);
			}
			break;
		case fmtop4RCC:
			vA = (int)buf[1];
			vB = (buf[3] << 8) | buf[2];
			vC = (buf[5] << 8) | buf[4];
			vH = (buf[7] << 8) | buf[6];
			flag_str = RZ_ASM_GET_NAME(a, 'm', vB);
			if (RZ_STR_ISNOTEMPTY(flag_str)) {
				rz_strf(str, " {v%i..v%i}, %s", vC, vC + vA - 1, flag_str);
			} else {
				rz_strf(str, " {v%i..v%i}, method+%i", vC, vC + vA - 1, vB);
			}
			strasm = rz_str_append(strasm, str);

			flag_str = RZ_ASM_GET_NAME(a, 'p', vH);
			if (RZ_STR_ISNOTEMPTY(flag_str)) {
				rz_strf(str, ", %s", flag_str);
			} else {
				rz_strf(str, ", proto+%i", vH);
			}
			strasm = rz_str_append(strasm, str);
			break;
		case fmtoptinvokeI: // Any opcode has this formats
		case fmtoptinvokeIR:
		case fmt00:
		default:
			free(strasm);
			strasm = NULL;
			size = 2;
		}
		rz_strbuf_set(&op->buf_asm, strasm ? strasm : "invalid");
	} else if (len > 0) {
		rz_strbuf_set(&op->buf_asm, "invalid");
		op->size = len;
		size = len;
	}

	if (payload < 0) {
		op->payload = 0;
	} else if (len > 0 && payload >= len) {
		op->payload = len;
	} else {
		op->payload = payload;
	}

	if (size + op->payload < 0) {
		op->size = 0;
	} else if (size + op->payload >= len) {
		op->size = len;
	} else {
		op->size = size + op->payload;
	}
	free(strasm);
	return size;
}

// TODO
static int dalvik_assemble(RzAsm *a, RzAsmOp *op, const char *buf) {
	int i;
	char *p = strchr(buf, ' ');
	if (p) {
		*p = 0;
	}
	// TODO: use a hashtable here
	for (i = 0; i < 256; i++) {
		if (!strcmp(dalvik_opcodes[i].name, buf)) {
			ut8 buf[4];
			rz_write_ble32(buf, i, a->big_endian);
			rz_strbuf_setbin(&op->buf, buf, sizeof(buf));
			op->size = dalvik_opcodes[i].len;
			return op->size;
		}
	}
	return 0;
}

RzAsmPlugin rz_asm_plugin_dalvik = {
	.name = "dalvik",
	.arch = "dalvik",
	.license = "LGPL3",
	.desc = "Dalvik (Android VM) bytecode disassembler",
	.bits = 32 | 64,
	.endian = RZ_SYS_ENDIAN_LITTLE,
	.disassemble = &dalvik_disassemble,
	.assemble = &dalvik_assemble,
};
