#include "checkouts.h"
#include "comp.h"

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

#include <emscripten/emscripten.h>

#define M_PVC 1
#define M_P 2
#define M_PVP 3

int delay_ms = 500;

// TODO refactor *everything*

struct match_state {
	int mode;
	struct leg *l1, *l2, *active_l;
	int active_p;
	int undone_count;
	int complete;
};

struct match_state *state;

void switch_active_user() {
	state->active_p = 3 - state->active_p;
	if (state->active_p == 1)
		state->active_l = state->l1;
	else
		state->active_l = state->l2;
	EM_ASM({setPlayerActive($0)}, state->active_p);
}

void set_user_active() {
	EM_ASM({setPlayerActive($0)}, 1);
	EM_ASM({setPromptHandler($0)}, "visit");
}

void set_boat_active() {
	EM_ASM({setPlayerActive($0)}, 2);
	EM_ASM({setPromptHandler()}, "");
}

void suggested(int rem, char *buf) {
	buf[0] = 0;

	if (rem > 1 && rem <= 170) {
		char *target = CHECKOUTS[2][rem-1];
		if (target) {
			int trem = rem - segment_points(segment_from_name(target));
			int len = sprintf(buf, "%s", target);
			if (trem) {
				target = CHECKOUTS[1][trem-1];
				len += sprintf(buf + len, "-%s", target);
				trem = trem - segment_points(segment_from_name(target));

				if (trem) {
					target = CHECKOUTS[0][trem-1];
					len += sprintf(buf + len, "-%s", target);
				}
			}
		}
	}
}

EMSCRIPTEN_KEEPALIVE void get_suggested(int rem, int player) {
	static char buf[20];
	suggested(rem, buf);
	EM_ASM({updatePlayerSugg($0, $1)}, player, buf);
}

EMSCRIPTEN_KEEPALIVE int is_match_over() {
	if (state->l1->rem <= 0 || state->l2->rem <= 0)
		return 1;
	return 0;
}

void match_over() {
	EM_ASM({setPromptHandler($0)}, "match_over");
	EM_ASM({promptMsgR($0)}, "Press OK to end match.");
	EM_ASM(setPlayerActive());
}

EMSCRIPTEN_KEEPALIVE void draw_match() {
	struct leg *l1 = state->l1;
	struct leg *l2 = state->l2;

	char visit_no[10], u_pts[10], u_rem[10], b_pts[10], b_rem[10], b_darts[100];

	sprintf(u_rem, "%d", l1->start);
	sprintf(b_rem, "%d", l2->start);
	EM_ASM({drawVisit($0, $1, $2, $3, $4, $5)},
		"0", "", u_rem, "", state->mode == M_P ? "" : b_rem, "");

	int n_visits = l1->n_visits > l2->n_visits ? l1->n_visits : l2->n_visits;
	for (int i = 0; i < n_visits; ++i) {
		visit_no[0] = u_pts[0] = u_rem[0] = b_pts[0] = b_rem[0] = b_darts[0] = 0;

		sprintf(visit_no, "%d", i + 1);

		struct visit *v = l1->visits + i;
		sprintf(u_pts, "%d", v->points);
		sprintf(u_rem, "%d", v->rem);

		if (i < l2->n_visits) {
			v = l2->visits + i;
			sprintf(b_pts, "%d", v->points);
			sprintf(b_rem, "%d", v->rem);

			for (int j = 0; j < v->n_darts; ++j) {
				char *n = segment_name(v->darts[j]);
				sprintf(b_darts + (j ? (j * 5 - 1) : 0), j == 0 ? "%4s" : " %4s", n);
				free(n);
			}
		}

		EM_ASM({drawVisit($0, $1, $2, $3, $4, $5)},
			visit_no, u_pts, u_rem, b_pts, b_rem, b_darts);
	}

	if (l1->rem <= 0) {
		EM_ASM({promptMsgL($0)}, "Darts needed?");
		EM_ASM({setPromptHandler($0)}, "num_darts");
	} else if (l2->rem <= 0) {
		if (state->mode == M_PVC) {
			EM_ASM({promptMsgL($0)}, "Bot wins. :(");
			match_over();
		} else {
			EM_ASM({promptMsgL($0)}, "Darts needed?");
			EM_ASM({setPromptHandler($0)}, "num_darts");
		}
	} else {
		EM_ASM({promptMsgL($0)}, "Enter points:");
	}
}

char *str_for_rem_state(int rem) {
	char *buf = malloc(10);

	if (rem < 0 || rem == 1)
		strcpy(buf, "BUST");
	else
		sprintf(buf, "%d", rem);

	return buf;
}

EMSCRIPTEN_KEEPALIVE void update_user_rem(int rem) {
	char *str = str_for_rem_state(rem);
	EM_ASM({updatePlayerRem($0, $1)}, state->active_p, str);
	free(str);

	get_suggested(rem, state->active_p);
}

EMSCRIPTEN_KEEPALIVE void update_user_rem_from_pts(int pts) {
	update_user_rem(state->active_l->rem - pts);
}

EMSCRIPTEN_KEEPALIVE void update_boat_rem(int rem) {
	char *str = str_for_rem_state(rem);
	EM_ASM({updatePlayerRem($0, $1)}, 2, str);
	free(str);

	//get_suggested(rem, 2);
}

void end_boat_throwing(int, double); // FIXME

EMSCRIPTEN_KEEPALIVE void boat_visit() {
	if (state->l1->rem <= 0 || state->l2->rem <= 0)
		return;

	EM_ASM({promptMsgL($0)}, "Bot is throwing…");

	struct leg *l = state->l2;
	if (state->undone_count) {
		--state->undone_count;
		l->rem = l->visits[l->n_visits++].rem;
	} else {
		comp_visit(l);
	}

	struct visit *v = l->visits + l->n_visits - 1;

	double avg;
	if (v->rem > 0)
		avg = (double)(l->start - l->rem) / l->n_visits;
	else
		avg = ((double)l->start / (((l->n_visits - 1) * 3) + v->n_darts)) * 3;

	if (!delay_ms) {
		end_boat_throwing(l->rem, avg);
		return;
	}

	int pts = 0;
	char str[20] = {0};

	for (int i = 0; i < v->n_darts; ++i) {
		pts += segment_points(v->darts[i]);
		char *seg_name = segment_name(v->darts[i]);
		if (i) strcat(str, "-");
		strcat(str, seg_name);
		free(seg_name);
		EM_ASM({scheduleCCall($0, $1, $2, $3, $4, $5)},
			"draw_boat_throwing", delay_ms * (i+1),
			"number", pts, "string", str);
	}

	EM_ASM({scheduleCCall($0, $1, $2, $3, $4, $5)},
		"end_boat_throwing", delay_ms * (v->n_darts + 1),
		"number", l->rem, "number", avg);
}

EMSCRIPTEN_KEEPALIVE bool user_visit(int points) {
	if (state->l1->rem <= 0 || state->l2->rem <= 0 ||
		points > state->active_l->rem || state->active_l->rem - points == 1 ||
		points > 180 || points == 179 || points == 178 || points == 176 ||
		points == 175 || points == 173 || points == 172 || points == 169 ||
		points == 166 || points == 163 ||
		(state->active_l->rem - points == 0 &&
			(points == 168 || points == 165 || points == 162 || points == 159))) {

		EM_ASM(oi());
		return false;
	}

	struct leg *l = state->active_l;
	struct visit *v = l->visits + l->n_visits++;
	v->points = points;
	l->rem -= points;
	v->rem = l->rem;
	update_user_rem(l->rem);

	if (v->rem > 0)
		EM_ASM({updatePlayerAvg($0, $1)}, state->active_p,
			(double)(l->start-l->rem)/l->n_visits);

	EM_ASM({clearVisits()});
	draw_match();

	if (!is_match_over()) {
		if (state->mode == M_PVC) {
			set_boat_active();
			boat_visit();
		} else if (state->mode == M_PVP) {
			switch_active_user();
		}
	}

	return true;
}

// FIXME neg
EMSCRIPTEN_KEEPALIVE void user_visit_to_rem(int rem) {
	user_visit(state->l1->rem - rem);
}

EMSCRIPTEN_KEEPALIVE bool user_undo() {
	if (!state->l1->n_visits) {
		EM_ASM(oi());
		return false;
	}

	if (state->mode == M_PVP) {
		if (is_match_over())
			EM_ASM({setPlayerActive($0)}, state->active_p);
		else
			switch_active_user();
	}

	if (state->mode == M_PVC)
		EM_ASM({setPlayerActive($0)}, state->active_p);

	struct leg *l = state->active_l;
	struct visit *v = l->visits + --l->n_visits;
	l->rem += v->points;
	if (state->mode == M_PVC && state->l2->n_visits > l->n_visits) {
		state->l2->rem += state->l2->visits[--state->l2->n_visits].points;
		++state->undone_count;
	}

	EM_ASM({updatePlayerAvg($0, $1)}, 1,
		l->n_visits ? (double)(l->start-l->rem)/l->n_visits : 0);
	EM_ASM({updatePlayerAvg($0, $1)}, 2,
		state->l2->n_visits ?
			(double)(state->l2->start-state->l2->rem)/state->l2->n_visits : 0);
	update_user_rem(l->rem);
	if (state->mode == M_PVC)
		update_boat_rem(state->l2->rem);

	memcpy(v, 0, sizeof(*v));

	EM_ASM({clearVisits()});
	EM_ASM({promptMsgR($0)}, "");
	EM_ASM({setPromptHandler($0)}, "visit");
	draw_match();

	return true;
}

EMSCRIPTEN_KEEPALIVE void draw_boat_throwing(int pts, char *str) {
	char buf[10];
	sprintf(buf, "%d", pts);

	int rem = state->l2->n_visits > 1 ?
		state->l2->visits[state->l2->n_visits-2].rem : state->l2->start;

	update_boat_rem(rem - pts);
	EM_ASM({setPromptInput($0)}, buf);
	EM_ASM({promptMsgR($0)}, str);
}

EMSCRIPTEN_KEEPALIVE void end_boat_throwing(int rem, double avg) {
	update_boat_rem(rem);
	EM_ASM({updatePlayerAvg($0, $1)}, 2, avg);
	EM_ASM({setPromptInput($0)}, "");
	EM_ASM(clearVisits());
	EM_ASM({promptMsgR($0)}, "");
	draw_match();

	if (!is_match_over())
		set_user_active();
}

EMSCRIPTEN_KEEPALIVE void resp_numdarts(int n_darts) {
	if (n_darts < 1 || n_darts > 3) {
		EM_ASM(oi());
		return;
	}

	struct leg *l = state->l1;

	EM_ASM({updatePlayerAvg($0, $1)}, state->active_p,
		((double)l->start / (((l->n_visits - 1) * 3) + n_darts)) * 3);
	EM_ASM({promptMsgL($0)}, "You win! :)");
	match_over();
}

void init_boat() {
	static int ran;

	if (ran) return;
	ran = 1;

	srand(time(NULL));
	init_board();

	EM_ASM({updateStdev($0)}, horizontal_stdev);
	EM_ASM({updateDelay($0)}, delay_ms);
}

EMSCRIPTEN_KEEPALIVE void free_match() {
	leg_free(state->l1);
	state->l2->n_visits += state->undone_count; // FIXME messy way to avoid memory leak
	leg_free(state->l2);
	free(state);
	state = NULL;
}

EMSCRIPTEN_KEEPALIVE void match_init() {
	for (int i = 1; i < 3; ++i) {
		EM_ASM({hidePlayerInfo($0)}, i);
		EM_ASM({updatePlayerName($0, $1)}, i, "");
		EM_ASM({updatePlayerRem($0, $1)}, i, "");
		EM_ASM({updatePlayerSugg($0, $1)}, i, "");
		EM_ASM({updatePlayerAvg($0, $1)}, i, 0);
	}
	EM_ASM(clearVisits());

	EM_ASM({setPromptHandler($0)}, "init");
	EM_ASM({promptMsgR($0)}, "");
	EM_ASM({promptMsgL($0)}, "Select match mode:");
}

EMSCRIPTEN_KEEPALIVE void start_match(int mode) {
	if (mode != M_PVP && mode != M_PVC && mode != M_P) {
		EM_ASM(oi());
		return;
	}

	if (state) free_match();

	init_boat();
	state = calloc(1, sizeof(*state));
	state->mode = mode;
	if (mode == M_PVC) {
		state->l1 = leg_init(501, "User");
		state->l2 = leg_init(501, "Bot");
	} else {
		state->l1 = leg_init(501, "Player 1");
		state->l2 = leg_init(501, "Player 2");
	}
	EM_ASM({showPlayerInfo($0)}, 1);
	if (mode != M_P)
		EM_ASM({showPlayerInfo($0)}, 2);
	state->active_p = 1;
	state->active_l = state->l1;

	EM_ASM({updatePlayerName($0, $1)}, 1, state->l1->name);
	EM_ASM({updatePlayerName($0, $1)}, 2, state->l2->name);
	update_user_rem(state->l1->rem);
	update_boat_rem(state->l2->rem);
	EM_ASM({updatePlayerAvg($0, $1)}, 1, 0);
	EM_ASM({updatePlayerAvg($0, $1)}, 2, 0);

	EM_ASM(clearVisits());
	set_user_active();
	EM_ASM({promptMsgR($0)}, "");
	draw_match();
}

EMSCRIPTEN_KEEPALIVE void set_stdev(float hstdev, float vstdev) {
	horizontal_stdev = hstdev;
	vertical_stdev = vstdev;
}

EMSCRIPTEN_KEEPALIVE void set_delay(int delay) {
	delay_ms = delay;
}

int main() {
	EM_ASM(read_opts());
	init_boat();
	match_init();
}