/* radare - LGPL - Copyright 2009-2018 - pancake, nibble */

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

#include <r_types.h>
#include <r_lib.h>
#include <r_util.h>
#include <r_asm.h>

#include "disas-asm.h"
#include "opcode/mips.h"
int mips_assemble(const char *str, ut64 pc, ut8 *out);

static int mips_mode = 0;
static unsigned long Offset = 0;
static RStrBuf *buf_global = NULL;
static unsigned char bytes[4];
static char *pre_cpu = NULL;
static char *pre_features = NULL;

static int mips_buffer_read_memory(bfd_vma memaddr, bfd_byte *myaddr, unsigned int length, struct disassemble_info *info) {
	int delta = (memaddr - Offset);
	if (delta < 0) {
		return -1;      // disable backward reads
	}
	if ((delta + length) > 4) {
		return -1;
	}
	memcpy (myaddr, bytes + delta, length);
	return 0;
}

static int symbol_at_address(bfd_vma addr, struct disassemble_info * info) {
	return 0;
}

static void memory_error_func(int status, bfd_vma memaddr, struct disassemble_info *info) {
	//--
}

DECLARE_GENERIC_PRINT_ADDRESS_FUNC()
DECLARE_GENERIC_FPRINTF_FUNC()

static int disassemble(struct r_asm_t *a, struct r_asm_op_t *op, const ut8 *buf, int len) {
	static struct disassemble_info disasm_obj;
	if (len < 4) {
		return -1;
	}
	buf_global = &op->buf_asm;
	Offset = a->pc;
	memcpy (bytes, buf, 4); // TODO handle thumb

	if ((a->cpu != pre_cpu) && (a->features != pre_features)) {
		free (disasm_obj.disassembler_options);
		memset (&disasm_obj, '\0', sizeof (struct disassemble_info));
	}	

	/* prepare disassembler */
	if (a->cpu && (!pre_cpu || !strcmp(a->cpu, pre_cpu))) {
		if (!r_str_casecmp (a->cpu, "mips64r2")) {
			disasm_obj.mach = bfd_mach_mipsisa64r2;
		} else if (!r_str_casecmp (a->cpu, "mips32r2")) {
			disasm_obj.mach = bfd_mach_mipsisa32r2;
		} else if (!r_str_casecmp (a->cpu, "mips64")) {
			disasm_obj.mach = bfd_mach_mipsisa64;
		} else if (!r_str_casecmp (a->cpu, "mips32")) {
			disasm_obj.mach = bfd_mach_mipsisa32;
		} else if (!r_str_casecmp (a->cpu, "loongson3a")) {
			disasm_obj.mach = bfd_mach_mips_gs464;
		} else if (!r_str_casecmp (a->cpu, "gs464")) {
			disasm_obj.mach = bfd_mach_mips_gs464;
		} else if (!r_str_casecmp (a->cpu, "gs464e")) {
			disasm_obj.mach = bfd_mach_mips_gs464e;
		} else if (!r_str_casecmp (a->cpu, "gs264e")) {
			disasm_obj.mach = bfd_mach_mips_gs264e;
		} else if (!r_str_casecmp (a->cpu, "loongson2e")) {
			disasm_obj.mach = bfd_mach_mips_loongson_2e;
		} else if (!r_str_casecmp (a->cpu, "loongson2f")) {
			disasm_obj.mach = bfd_mach_mips_loongson_2f;
		} else if (!r_str_casecmp (a->cpu, "mips32/64")) {
			//Fallback for default config
			disasm_obj.mach = bfd_mach_mips_loongson_2f;
		}
		pre_cpu = r_str_dup (pre_cpu, a->cpu);
	}
	else {
		disasm_obj.mach = bfd_mach_mips_loongson_2f;
	}

	if (a->features && (!pre_features || !strcmp (a->features, pre_features))) {
		free (disasm_obj.disassembler_options);
		if (strstr (a->features, "n64")) {
			disasm_obj.disassembler_options = r_str_new ("abi=n64");
		} else if (strstr (a->features, "n32")) {
			disasm_obj.disassembler_options = r_str_new ("abi=n32");
		} else if (strstr (a->features, "o32")) {
			disasm_obj.disassembler_options = r_str_new ("abi=o32");
		}
		pre_features = r_str_dup (pre_features, a->features);
	}

	mips_mode = a->bits;
	disasm_obj.arch = CPU_LOONGSON_2F;
	disasm_obj.buffer = bytes;
	disasm_obj.read_memory_func = &mips_buffer_read_memory;
	disasm_obj.symbol_at_address_func = &symbol_at_address;
	disasm_obj.memory_error_func = &memory_error_func;
	disasm_obj.print_address_func = &generic_print_address_func;
	disasm_obj.buffer_vma = Offset;
	disasm_obj.buffer_length = 4;
	disasm_obj.endian = !a->big_endian;
	disasm_obj.fprintf_func = &generic_fprintf_func;
	disasm_obj.stream = stdout;
	op->size = (disasm_obj.endian == BFD_ENDIAN_LITTLE)
		? print_insn_little_mips ((bfd_vma)Offset, &disasm_obj)
		: print_insn_big_mips ((bfd_vma)Offset, &disasm_obj);
	if (op->size == -1) {
		r_strbuf_set (&op->buf_asm, "(data)");
	}
	return op->size;
}

static int assemble(RAsm *a, RAsmOp *op, const char *str) {
	ut8 *opbuf = (ut8*)r_strbuf_get (&op->buf);
	int ret = mips_assemble (str, a->pc, opbuf);
	if (a->big_endian) {
		ut8 tmp = opbuf[0];
		opbuf[0] = opbuf[3];
		opbuf[3] = tmp;
		tmp = opbuf[1];
		opbuf[1] = opbuf[2];
		opbuf[2] = tmp;
	}
	return ret;
}

RAsmPlugin r_asm_plugin_mips_gnu = {
	.name = "mips.gnu",
	.arch = "mips",
	.license = "GPL3",
	.bits = 32 | 64,
	.endian = R_SYS_ENDIAN_LITTLE | R_SYS_ENDIAN_BIG,
	.desc = "MIPS CPU",
	.disassemble = &disassemble,
	.assemble = &assemble
};

#ifndef R2_PLUGIN_INCORE
R_API RLibStruct radare_plugin = {
	.type = R_LIB_TYPE_ASM,
	.data = &r_asm_plugin_mips_gnu,
	.version = R2_VERSION
};
#endif
