#include <stdio.h>

typedef unsigned char Uint8;
typedef signed char Sint8;
typedef unsigned short Uint16;

typedef struct {
	Uint8 dat[0x100], ptr;
} Stack;

typedef struct Uxn {
	Uint8 ram[0x10000], dev[0x100];
	Stack wst, rst;
} Uxn;

Uxn uxn;

/* I/O */

Uint8
emu_dei(Uint8 addr)
{
	return uxn.dev[addr];
}

void
emu_deo(Uint8 addr, Uint8 value)
{
	uxn.dev[addr] = value;
	switch(addr) {
	case 0x18: fputc(uxn.dev[0x18], stdout); return;
	case 0x19: fputc(uxn.dev[0x19], stderr); return;
	}
}

/* Unroll */

#define OPC(opc, init, body) {\
	case 0x00|opc: {enum{_2=0,_r=0};init body;} break;\
	case 0x20|opc: {enum{_2=1,_r=0};init body;} break;\
	case 0x40|opc: {enum{_2=0,_r=1};init body;} break;\
	case 0x60|opc: {enum{_2=1,_r=1};init body;} break;\
	case 0x80|opc: {enum{_2=0,_r=0};int k=uxn.wst.ptr;init uxn.wst.ptr= k;body;} break;\
	case 0xa0|opc: {enum{_2=1,_r=0};int k=uxn.wst.ptr;init uxn.wst.ptr= k;body;} break;\
	case 0xc0|opc: {enum{_2=0,_r=1};int k=uxn.rst.ptr;init uxn.rst.ptr= k;body;} break;\
	case 0xe0|opc: {enum{_2=1,_r=1};int k=uxn.rst.ptr;init uxn.rst.ptr= k;body;} break;\
}

/* Microcode */

#define JMI pc += uxn.ram[pc++] << 8 | uxn.ram[pc++];
#define JMP(i) if(_2) pc = i; else pc += (Sint8)i;
#define REM if(_r) uxn.rst.ptr -= 1 + _2; else uxn.wst.ptr -= 1 + _2;
#define INC(s) uxn.s.dat[uxn.s.ptr++]
#define DEC(s) uxn.s.dat[--uxn.s.ptr]
#define POx(o) if(_2) { PO2(o) } else PO1(o)
#define PO1(o) o = _r ? DEC(rst) : DEC(wst);
#define PO2(o) PO1(o) o |= (_r ? DEC(rst) : DEC(wst)) << 8;
#define PUx(i) if(_2) { c = (i); PU1(c >> 8) PU1(c) } else PU1(i)
#define PU1(i) if(_r) INC(rst) = i; else INC(wst) = i;
#define RP1(i) if(_r) INC(wst) = i; else INC(rst) = i;
#define GET(o) if(_2) PO1(o[1]) PO1(o[0])
#define PUT(i) PU1(i[0]) if(_2) PU1(i[1])
#define DEI(i,o) o[0] = emu_dei(i); if(_2) o[1] = emu_dei(i + 1); PUT(o)
#define DEO(i,j) emu_deo(i, j[0]); if(_2) emu_deo(i + 1, j[1]);
#define PEK(i,o,m) o[0] = uxn.ram[i]; if(_2) o[1] = uxn.ram[(i + 1) & m]; PUT(o)
#define POK(i,j,m) uxn.ram[i] = j[0]; if(_2) uxn.ram[(i + 1) & m] = j[1];

int
uxn_eval(Uint16 pc)
{
	int a, b, c, x[2], y[2], z[2];
	if(!pc || uxn.dev[0x0f]) return 0;
	for(;;) {
		switch(uxn.ram[pc++]) {
		/* BRK */ case 0x00: return 1;
		/* JCI */ case 0x20: if(DEC(wst)) { JMI break; } pc += 2; break;
		/* JMI */ case 0x40: JMI break;
		/* JSI */ case 0x60: c = pc + 2; INC(rst) = c >> 8; INC(rst) = c; JMI break;
		/* LI2 */ case 0xa0: INC(wst) = uxn.ram[pc++];
		/* LIT */ case 0x80: INC(wst) = uxn.ram[pc++]; break;
		/* L2r */ case 0xe0: INC(rst) = uxn.ram[pc++];
		/* LIr */ case 0xc0: INC(rst) = uxn.ram[pc++]; break;
		/* INC */ OPC(0x01, POx(a), PUx(a + 1))
		/* POP */ OPC(0x02, REM, 0)
		/* NIP */ OPC(0x03, GET(x) REM,PUT(x))
		/* SWP */ OPC(0x04, GET(x) GET(y),PUT(x) PUT(y))
		/* ROT */ OPC(0x05, GET(x) GET(y) GET(z),PUT(y) PUT(x) PUT(z))
		/* DUP */ OPC(0x06, GET(x),PUT(x) PUT(x))
		/* OVR */ OPC(0x07, GET(x) GET(y),PUT(y) PUT(x) PUT(y))
		/* EQU */ OPC(0x08, POx(a) POx(b),PU1(b == a))
		/* NEQ */ OPC(0x09, POx(a) POx(b),PU1(b != a))
		/* GTH */ OPC(0x0a, POx(a) POx(b),PU1(b > a))
		/* LTH */ OPC(0x0b, POx(a) POx(b),PU1(b < a))
		/* JMP */ OPC(0x0c, POx(a),JMP(a))
		/* JCN */ OPC(0x0d, POx(a) PO1(b), if(b) JMP(a))
		/* JSR */ OPC(0x0e, POx(a),RP1(pc >> 8) RP1(pc) JMP(a))
		/* STH */ OPC(0x0f, GET(x),RP1(x[0]) if(_2) RP1(x[1]))
		/* LDZ */ OPC(0x10, PO1(a),PEK(a, x, 0xff))
		/* STZ */ OPC(0x11, PO1(a) GET(y),POK(a, y, 0xff))
		/* LDR */ OPC(0x12, PO1(a),PEK(pc + (Sint8)a, x, 0xffff))
		/* STR */ OPC(0x13, PO1(a) GET(y),POK(pc + (Sint8)a, y, 0xffff))
		/* LDA */ OPC(0x14, PO2(a),PEK(a, x, 0xffff))
		/* STA */ OPC(0x15, PO2(a) GET(y),POK(a, y, 0xffff))
		/* DEI */ OPC(0x16, PO1(a),DEI(a, x))
		/* DEO */ OPC(0x17, PO1(a) GET(y),DEO(a, y))
		/* ADD */ OPC(0x18, POx(a) POx(b),PUx(b + a))
		/* SUB */ OPC(0x19, POx(a) POx(b),PUx(b - a))
		/* MUL */ OPC(0x1a, POx(a) POx(b),PUx(b * a))
		/* DIV */ OPC(0x1b, POx(a) POx(b),PUx(a ? b / a : 0))
		/* AND */ OPC(0x1c, POx(a) POx(b),PUx(b & a))
		/* ORA */ OPC(0x1d, POx(a) POx(b),PUx(b | a))
		/* EOR */ OPC(0x1e, POx(a) POx(b),PUx(b ^ a))
		/* SFT */ OPC(0x1f, PO1(a) POx(b),PUx(b >> (a & 0xf) << (a >> 4)))
		}
	}
}

void
console_input(char c, int type)
{
	uxn.dev[0x12] = c, uxn.dev[0x17] = type;
	uxn_eval(uxn.dev[0x10] << 8 | uxn.dev[0x11]);
}

int
main(int argc, char **argv)
{
	FILE *f;
	int i = 1;
	if(argc < 2) {
		fprintf(stdout, "usage: %s file.rom [args..]\n", argv[0]);
		return 0;
	}
	f = fopen(argv[i++], "rb");
	if(!f) {
		fprintf(stderr, "uxnmin: Error %s\n", argv[1]);
		return 0;
	}
	uxn.dev[0x17] = argc - i;
	fread(&uxn.ram[0x0100], 0xff00, 1, f), fclose(f);
	if(uxn_eval(0x0100) && (uxn.dev[0x10] << 8 | uxn.dev[0x11])) {
		for(; i < argc; i++) {
			char *p = argv[i];
			while(*p) console_input(*p++, 0x2);
			console_input('\n', i == argc - 1 ? 0x4 : 0x3);
		}
		while(!uxn.dev[0x0f]) {
			int c = fgetc(stdin);
			if(c == EOF) {
				console_input(0x00, 0x4);
				break;
			}
			console_input((Uint8)c, 0x1);
		}
	}
	return uxn.dev[0x0f] & 0x7f;
}