#define NCURSES_WIDECHAR 1

#include "tpu.h"
#include "util.h"
#include "asm.h"

#include <curses.h>

#include <sys/inotify.h>
#include <unistd.h>
#include <locale.h>

#include <errno.h>
#include <ctype.h>
#include <stdarg.h>
#include <string.h>
#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>

#define KEY_ESC 0x1b
#define KEY_CTRL(c) ((c) & ~0x60)

#define TPU_INFO_W 7
#define TPU_INFO_H 4
#define TPU_W (1 + TPU_MAX_COLS + TPU_INFO_W)
#define TPU_H (1 + TPU_MAX_ROWS + 1)

#define TIMEOUT 50

enum input_mode {
	MAIN,
	TPU_NAV
};

enum {
	NONE, MIN, MAX, MID
};

enum {
	THEME_DEFAULT,
	THEME_DISABLED
};

static const char *mode_repr[] = {
	"IDL", "RUN", "REA", "WRI"
};

static int scrx = 0;
static int scry = 0;
static int scrw = 80;
static int scrh = 40;

static struct tis tis;

static int show_reloaded = 0;

static enum input_mode input_mode = MAIN;

static struct tpu *tpu_sel = NULL;

int (*cleanup)(void) = endwin;
const char *progname = "tis100-curses";

static enum tpu_port_dir
key_to_dir(int key)
{
	switch (key) {
	case KEY_LEFT:
		return DIR_LEFT;
	case KEY_RIGHT:
		return DIR_RIGHT;
	case KEY_UP:
		return DIR_UP;
	case KEY_DOWN:
		return DIR_DOWN;
	default:
		abort();
	}
}

static const cchar_t *
dir_to_arrow(enum tpu_port_dir dir)
{
	switch (dir) {
	case DIR_UP:
		return WACS_UARROW;
	case DIR_DOWN:
		return WACS_DARROW;
	case DIR_LEFT:
		return WACS_LARROW;
	case DIR_RIGHT:
		return WACS_RARROW;
	}
}

static int
tpu_pos_x(struct tpu *tpu)
{
	return 2 + (int) tpu->x * (TPU_W + 4);
}

static int
tpu_pos_y(struct tpu *tpu)
{
	return 2 + (int) tpu->y * (TPU_H + 2);
}

static void
tui_draw_box(int sx, int sy, int w, int h, attr_t attr,
	const cchar_t *ul, const cchar_t *ur,
	const cchar_t *ll, const cchar_t *lr)
{
	int x, y;

	if (sx + w < scrx || sx >= scrx + scrw) return;
	if (sy + h < scry || sy >= scry + scrh) return;

	sx -= scrx;
	sy -= scry;

	attron(attr);
	mvadd_wch(sy, sx, ul);
	mvadd_wch(sy, sx + w - 1, ur);
	mvadd_wch(sy + h - 1, sx, ll);
	mvadd_wch(sy + h - 1, sx + w - 1, lr);
	for (x = sx + 1; x < sx + w - 1; x++)
		mvadd_wch(sy, x, WACS_D_HLINE);
	for (x = sx + 1; x < sx + w - 1; x++)
		mvadd_wch(sy + h - 1, x, WACS_D_HLINE);
	for (y = sy + 1; y < sy + h - 1; y++)
		mvadd_wch(y, sx, WACS_D_VLINE);
	for (y = sy + 1; y < sy + h - 1; y++)
		mvadd_wch(y, sx + w - 1, WACS_D_VLINE);
	attroff(attr);
}

static void
__attribute__((format(printf, 4, 5)))
tui_draw_text(int x, int y, attr_t attr, const char *fmt, ...)
{
	char buf[256];
	va_list ap;
	int i;

	va_start(ap, fmt);
	vsnprintf(buf, 256, fmt, ap);
	va_end(ap);

	attron(attr);
	for (i = 0; i < strlen(buf) && x + i < scrx + scrw; i++)
		mvaddch(y - scry, x + i - scrx, (chtype) buf[i]);
	attroff(attr);
}

static void
tui_draw_lit(int x, int y, attr_t attr, int lit)
{
	char buf[6];

	snprintf(buf, 5, "% 04i", lit);
	tui_draw_text(x, y, attr, "%.*s", 4, buf);
}

static void
tui_draw_wch(int x, int y, attr_t attr, const cchar_t *c)
{
	attron(attr);
	mvadd_wch(y - scry, x - scrx, c);
	attroff(attr);
}

static void
tui_draw_tpu(struct tpu *tpu)
{
	char rowbuf[TPU_MAX_COLS + 1];
	struct tpu_port *port;
	int sx, sy, x, y, w, h;
	int offx, offy, start, inst;
	struct label *label;
	size_t len;
	attr_t attr;
	int idle;

	attr = (tpu_sel == tpu && input_mode == TPU_NAV) ? A_BOLD : 0;
	attr |= tpu->disabled ? COLOR_PAIR(THEME_DISABLED) : COLOR_PAIR(THEME_DEFAULT);

	sx = tpu_pos_x(tpu);
	sy = tpu_pos_y(tpu);
	tui_draw_box(sx, sy, TPU_W, TPU_H, attr,
		WACS_D_ULCORNER, WACS_D_URCORNER,
		WACS_D_LLCORNER, WACS_D_LRCORNER);

	if (tpu->disabled) {
		tui_draw_text(sx + 4, sy + 1 + 1, attr | A_REVERSE, "             ");
		tui_draw_text(sx + 4, sy + 1 + 3, attr | A_BOLD,    "COMMUNICATION");
		tui_draw_text(sx + 4, sy + 1 + 4, attr | A_BOLD,    "   FAILURE   ");
		tui_draw_text(sx + 4, sy + 1 + 6, attr | A_REVERSE, "             ");
	} else if (tpu->inst_cnt > 0) {
		start = MAX(0, MIN(tpu->pc - 4, (int) tpu->inst_cnt - TPU_MAX_ROWS));
		inst = start;
		for (offy = 0; offy < TPU_MAX_ROWS && inst < tpu->inst_cnt; ) {
			asm_print_inst(rowbuf, sizeof(rowbuf), &tpu->insts[inst],
				TPU_MAX_COLS - (size_t) offx);
			label = &tpu->label_map.labels[inst];
			if (label->str) {
				len = strlen(label->str);
				tui_draw_text(sx + 1 + offx, sy + 1 + offy,
					A_DIM, "%s:", label->str);
				if (label->prefix) {
					offx += (int) strlen(label->str) + 1;
					if (offx + 1 + (int) strlen(rowbuf) <= TPU_MAX_COLS)
						offx += 1;
				} else {
					offy += 1;
				}
			}
			if ((size_t) offx + strlen(rowbuf) > TPU_MAX_COLS)
				asm_print_inst(rowbuf, sizeof(rowbuf), &tpu->insts[inst],
					TPU_MAX_COLS - (size_t) offx);
			tui_draw_text(sx + 1 + offx, sy + 1 + offy,
				inst == tpu->pc ?
				A_STANDOUT | (tpu->idle ? A_DIM : 0) : 0,
				"%-*.*s", TPU_MAX_COLS - offx,
				TPU_MAX_COLS, rowbuf);
			inst += 1;
			offy += 1;
			offx = 0;
		}
	}

	x = sx + TPU_W - TPU_INFO_W;
	y = sy;
	w = TPU_INFO_W;
	h = TPU_INFO_H;
	tui_draw_box(x, y, w, h, attr,
		WACS_D_TTEE, WACS_D_URCORNER, WACS_D_LTEE, WACS_D_RTEE);
	tui_draw_text(x + 2, y + 1, attr | A_BOLD, "ACC");
	tui_draw_lit(x + 1, y + 2, attr, tpu->acc);

	tui_draw_box(x, (y += TPU_INFO_H - 1), w, h, attr,
		WACS_D_LTEE, WACS_D_RTEE, WACS_D_LTEE, WACS_D_RTEE);
	tui_draw_text(x + 2, y + 1, attr | A_BOLD, "BAK");
	tui_draw_lit(x + 1, y + 2, attr, tpu->bak);

	tui_draw_box(x, (y += TPU_INFO_H - 1), w, h, attr,
		WACS_D_LTEE, WACS_D_RTEE, WACS_D_LTEE, WACS_D_RTEE);
	tui_draw_text(x + 2, y + 1, attr | A_BOLD, "LST");
	if (tpu->last < 0) {
		tui_draw_text(x + 2, y + 2, attr, "N/A");
	} else {
		tui_draw_wch(x + 2, y + 2, attr,
			dir_to_arrow((enum tpu_port_dir) tpu->last));
		tui_draw_wch(x + 3, y + 2, attr,
			dir_to_arrow((enum tpu_port_dir) tpu->last));
		tui_draw_wch(x + 4, y + 2, attr,
			dir_to_arrow((enum tpu_port_dir) tpu->last));
	}

	tui_draw_box(x, (y += TPU_INFO_H - 1), w, h, attr,
		WACS_D_LTEE, WACS_D_RTEE, WACS_D_LTEE, WACS_D_RTEE);
	tui_draw_text(x + 2, y + 1, attr | A_BOLD, "MOD");
	tui_draw_text(x + 2, y + 2, attr, "%s", mode_repr[tpu->mode]);

	tui_draw_box(x, (y += TPU_INFO_H - 1), w, h, attr,
		WACS_D_LTEE, WACS_D_RTEE, WACS_D_BTEE, WACS_D_RTEE);
	tui_draw_text(x + 2, y + 1, attr | A_BOLD, "IDL");
	if (tpu->steps > 0)
		idle = (int) ((double) tpu->idle_steps * 100 / (double) tpu->steps);
	else
		idle = 0;
	tui_draw_text(x + 2, y + 2, attr, "%03i", idle);

	tui_draw_box(x, (y += TPU_INFO_H - 1), w, 2, attr,
		WACS_D_LTEE, WACS_D_RTEE, WACS_D_BTEE, WACS_D_LRCORNER);

	if (tpu->ports[DIR_LEFT].attached) {
		port = &tpu->ports[DIR_LEFT];
		if (port->avail)
			tui_draw_lit(sx - 4, sy + 6, A_BOLD, port->in);
		if (port->type & PORT_IN)
			tui_draw_wch(sx - 1, sy + 7,
				port->avail ? A_BOLD : 0, WACS_RARROW);
		if (port->type & PORT_OUT)
			tui_draw_wch(sx - 1, sy + 8,
				port->writing ? A_BOLD : 0, WACS_LARROW);
		if (port->writing)
			tui_draw_lit(sx - 4, sy + 10, A_BOLD, port->out);
	}

	if (tpu->ports[DIR_RIGHT].attached) {
		port = &tpu->ports[DIR_RIGHT];
		if (port->writing)
			tui_draw_lit(sx + TPU_W, sy + 5, A_BOLD, port->out);
		if (port->type & PORT_OUT)
			tui_draw_wch(sx + TPU_W, sy + 7,
				port->writing ? A_BOLD : 0, WACS_RARROW);
		if (port->type & PORT_IN)
			tui_draw_wch(sx + TPU_W, sy + 8,
				port->avail ? A_BOLD : 0, WACS_LARROW);
		if (port->avail)
			tui_draw_lit(sx + TPU_W, sy + 9, A_BOLD, port->in);
	}

	if (tpu->ports[DIR_UP].attached) {
		port = &tpu->ports[DIR_UP];
		if (port->dst_port->io)
			tui_draw_text(sx + 10, sy - 1, A_BOLD,
				"IN.%c", toupper(port->dst_port->io->c));
		if (port->writing)
			tui_draw_lit(sx + 8, sy - 1, A_BOLD, port->out);
		if (port->type & PORT_OUT)
			tui_draw_wch(sx + 13, sy - 1,
				port->writing ? A_BOLD : 0, WACS_UARROW);
		if (port->type & PORT_IN)
			tui_draw_wch(sx + 15, sy - 1,
				port->avail ? A_BOLD : 0, WACS_DARROW);
		if (port->avail)
			tui_draw_lit(sx + 16, sy - 1, A_BOLD, port->in);
	}

	if (tpu->ports[DIR_DOWN].attached) {
		port = &tpu->ports[DIR_DOWN];
		if (port->dst_port->io)
			tui_draw_text(sx + 9, sy + TPU_H, A_BOLD,
				"OUT.%c", toupper(port->dst_port->io->c));
		if (port->avail)
			tui_draw_lit(sx + 8, sy + TPU_H, A_BOLD, port->in);
		if (port->type & PORT_IN)
			tui_draw_wch(sx + 13, sy + TPU_H,
				port->avail ? A_BOLD : 0, WACS_UARROW);
		if (port->type & PORT_OUT)
			tui_draw_wch(sx + 15, sy + TPU_H,
				port->writing ? A_BOLD : 0, WACS_DARROW);
		if (port->writing)
			tui_draw_lit(sx + 16, sy + TPU_H, A_BOLD, port->out);
	}
}

static void
tui_draw(void)
{
	struct tpu_map_link *link;
	size_t i;
	int tx;

	clear();
	for (i = 0; i < TPU_MAP_BUCKETS; i++) {
		for (link = tis.tpu_map.buckets[i]; link; link = link->next)
			tui_draw_tpu(link->tpu);
	}
	if (show_reloaded > 0) {
		tx = MAX(0, scrx + scrw / 2 - 4);
		tui_draw_text(scrx, scry, A_STANDOUT, "%-*s", scrw, "");
		tui_draw_text(tx, scry, A_STANDOUT, "RELOADED");
		show_reloaded--;
	}
	refresh();
}

static void
tui_resize(void)
{
	scrw = getmaxx(stdscr);
	scrh = getmaxy(stdscr);
}

static void
tui_seek(struct tpu *tpu, int dx, int dy)
{
	struct tpu_map_link *link;
	int minx, miny, maxx, maxy;
	int x, y;
	size_t i;

	if (tpu) {
		minx = maxx = tpu_pos_x(tpu);
		miny = maxy = tpu_pos_y(tpu);
 	} else {
		minx = miny = maxx = maxy = -1;
		for (i = 0; i < TPU_MAP_BUCKETS; i++) {
			link = tis.tpu_map.buckets[i];
			for (; link; link = link->next) {
				if (tpu && tpu != link->tpu)
					continue;
				x = tpu_pos_x(link->tpu);
				if (minx == -1 || x < minx) minx = x;
				if (maxx == -1 || x > maxx) maxx = x;
				y = tpu_pos_y(link->tpu);
				if (miny == -1 || y < miny) miny = y;
				if (maxy == -1 || y > maxy) maxy = y;
			}
		}
		if (minx == -1 || miny == -1) return;
	}

	if (dx == MIN) scrx = minx - 2;
	else if (dx == MAX) scrx = maxx + TPU_W + 2 - scrw;
	else if (dx == MID) scrx = (minx + maxx + TPU_W - scrw) / 2;

	if (dy == MIN) scry = miny - 2;
	else if (dy == MAX) scry = maxy + TPU_H + 2 - scrh;
	else if (dy == MID) scry = (miny + maxy + TPU_H - scrh) / 2;
}

static void
handlekey(int key)
{
	enum tpu_port_dir dir;

	if (input_mode == MAIN) {
		switch (key) {
		case 'I':
			input_mode = TPU_NAV;
			break;
		case KEY_UP:
			scry -= 2;
			break;
		case KEY_DOWN:
			scry += 2;
			break;
		case KEY_LEFT:
			scrx -= 4;
			break;
		case KEY_RIGHT:
			scrx += 4;
			break;
		case 's':
			tis_step(&tis);
			break;
		}
	} else {
		switch (key) {
		case KEY_ESC:
			input_mode = MAIN;
			break;
		case KEY_UP:
		case KEY_DOWN:
		case KEY_LEFT:
		case KEY_RIGHT:
			dir = key_to_dir(key);
			if (tpu_sel && tpu_sel->ports[dir].dst_port->tpu)
				tpu_sel = tpu_sel->ports[dir].dst_port->tpu;
			tui_seek(tpu_sel, MID, MID);
			break;
		}
	}
}

static struct tpu *
first_tpu(void)
{
	size_t i;

	for (i = 0; i < TPU_MAP_BUCKETS; i++) {
		if (tis.tpu_map.buckets[i])
			return tis.tpu_map.buckets[i]->tpu;
	}

	return NULL;
}

static void
reset(int ifd, int argc, const char **argv, bool watch)
{
	tis_deinit(&tis);
	tis_init(&tis);
	tis_load(&tis, argv);

	if (watch) {
		if (inotify_add_watch(ifd, tis.asm_filepath, IN_MODIFY) < 0)
			die("inotify_add_watch '%s':", argv[1]);
	}

	tpu_sel = first_tpu();
}

int
main(int argc, const char **argv)
{
	struct inotify_event event;
	ssize_t len;
	bool quit;
	int key;
	int ifd;

	if (argc < 2) {
		fprintf(stderr, "Usage: tis100-curses FILE [IO..]\n");
		exit(1);
	}

	setlocale(LC_ALL, "");

	initscr();

	raw();
	noecho();
	keypad(stdscr, TRUE);
	start_color();
	init_pair(THEME_DEFAULT, COLOR_WHITE, COLOR_BLACK);
	init_pair(THEME_DISABLED, COLOR_RED, COLOR_BLACK);
	curs_set(0);
	tui_resize();
	timeout(TIMEOUT);
	ESCDELAY = 0;

	tis_init(&tis);

	ifd = inotify_init1(IN_NONBLOCK);

	reset(ifd, argc, argv, true);

	quit = false;
	while (!quit) {
		len = read(ifd, &event, sizeof(event));
		if (len < 0 && errno != EAGAIN)
			die("inotify_read:");
		if (len >= 0) {
			reset(ifd, argc, argv, true);
			show_reloaded = 1000 / TIMEOUT;
		}

		tui_draw();
		key = getch();
		switch (key) {
		case KEY_RESIZE:
			tui_resize();
			break;
		case 'g':
			tui_seek(tpu_sel, MID, MID);
			break;
		case 'h':
			tui_seek(NULL, MID, MID);
			break;
		case 'r':
			reset(ifd, argc, argv, false);
			break;
		case 'q':
		case KEY_CTRL('c'):
			quit = true;
			break;
		default:
			handlekey(key);
			break;
		}
	}

	tis_deinit(&tis);

	close(ifd);

	endwin();
}