#include "web_control.h"
#include "web_dom.h"
#include "web_match.h"
#include "web_opts.h"
#include "web_prompt.h"
#include "web_scoreboard.h"
#include "web_svg.h"

#include "comp.h"

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

#include <emscripten/emscripten.h>

static int curr_match_id = 0;

void set_active_player(int pn)
{
	state->active_player = pn;
	scoreboard_set_player_active(pn);

	if (state->mode == M_PVC && pn == 2)
		prompt_bot_visit();
	else
		prompt_visit();
}

void toggle_active_player()
{
	set_active_player(3 - state->active_player);
}

void update_user_rem_from_pts(int pts)
{
	update_player_rem(state->active_player, state_active_leg()->rem - pts);
	scoreboard_flush_player_info(state->active_player);
}

EMSCRIPTEN_KEEPALIVE
void end_boat_visit(int rem, double avg, int match_id)
{
	if (!state || match_id != curr_match_id)
		return;

	svg_clear_points();
	update_player_rem(2, rem);
	scoreboard_set_player_avg(2, avg);
	prompt_set_input(NULL);
	prompt_set_msgr(NULL);

	draw_visits();
	handle_next();
}

EMSCRIPTEN_KEEPALIVE
void draw_boat_throwing(int pts, char *str, double x, double y, int match_id)
{
	if (!state || match_id != curr_match_id)
		return;

	char pts_str[10];
	sprintf(pts_str, "%d", pts);

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

	svg_draw_point(x, y);
	update_player_rem(2, rem - pts);
	prompt_set_input(pts_str);
	prompt_set_msgr(str);
	free(str);

	prompt_flush();
	scoreboard_flush_player_info(2);
}

static void schedule_boat_visit_draws(struct leg *l, struct visit *v,
	double avg)
{
	int pts = 0;
	char str[15] = {0};
	size_t len_str = 0;

	for (int i = 0; i < v->n_darts; ++i) {
		pts += segment_points(v->darts[i]);
		char *seg_name = segment_name(v->darts[i]);
		len_str += sprintf(str + len_str, i ? "-%s" : "%s", seg_name);
		free(seg_name);

		struct ccoords c = v->ccoords[i];

		int delay = delay_ms * (i + 1);
		if (delay_ms >= SVG_THROW_ANIM_MS)
			delay -= SVG_THROW_ANIM_MS;

		char *tmp = malloc(len_str + 1); // free in draw_boat_throwing
		memcpy(tmp, str, len_str + 1);
		EM_ASM({scheduleCCall($0, $1, $2, $3, $4, $5, $6)},
			"draw_boat_throwing", delay,
			pts, tmp, c.x, c.y, curr_match_id);
	}

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

void boat_visit()
{
	struct leg *l = state->legs[1];
	if (state->boat_undone) {
		--state->boat_undone;
		l->rem = l->visits[l->n_visits++].rem;
	} else {
		comp_visit(l);
	}

	struct visit *v = l->visits + l->n_visits - 1;
	double avg = v->rem > 0 ?
		(double)(l->start - l->rem) / l->n_visits :
		(double)l->start / (((l->n_visits - 1) * 3) + v->n_darts) * 3;

	if (delay_ms)
		schedule_boat_visit_draws(l, v, avg);
	else
		end_boat_visit(l->rem, avg, curr_match_id);
}

void handle_next()
{
	if (!state) {
		prompt_select_mode();
	} else if (match_is_over()) {
		if (state->num_darts ||
			(state->mode == M_PVC && state->legs[1]->rem <= 0))
			prompt_end_match();
		else
			prompt_num_darts();
	} else {
		if (state->mode == M_P) {
			set_active_player(1);
		} else {
			if (state->active_player)
				toggle_active_player();
			else
				set_active_player(match_opts->throws_first);

			if (state->mode == M_PVC && state->active_player == 2)
				boat_visit();
		}
	}

	prompt_flush();
	scoreboard_flush();
}

void user_visit(int points)
{
	if (!is_points_valid(points, state_active_leg()->rem)) {
		oi();
		return;
	}

	struct leg *l = state_active_leg();
	if (l->n_visits == l->size_visits)
		leg_grow_visits(l);
	struct visit *v = l->visits + l->n_visits++;
	v->points = points;
	l->rem -= points;
	v->rem = l->rem;
	update_player_rem(state->active_player, l->rem);

	if (v->rem > 0)
		update_player_avg(state->active_player, 0);

	draw_visits();
	handle_next();
}

void user_visit_to_rem(int rem)
{
	user_visit(state->legs[0]->rem - rem);
}

static int num_players()
{
	if (state->mode == M_P)
		return 1;

	return 2;
}

static int prev_throw_player()
{
	if (match_is_over())
		return state->active_player;

	if (state->active_player == 1)
		return num_players();
	else
		return state->active_player - 1;
}

static bool player_is_comp(int pn)
{
	return state->mode == M_PVC && pn == 2;
}

static void undo_active()
{
	struct leg *l = state_active_leg();

	if (player_is_comp(state->active_player)) {
		l->rem += l->visits[--l->n_visits].points;
		++state->boat_undone;
	} else {
		struct visit *v = l->visits + --l->n_visits;
		l->rem += v->points;
		memset(v, 0, sizeof(*v));
	}

	update_player_avg(state->active_player, 0);
	update_player_rem(state->active_player, l->rem);

	state->active_player = prev_throw_player();
}

static bool first_user_has_thrown() {
	for (int i = 0, np = num_players(); i < np; ++i) {
		int pn = match_opts->throws_first + i;
		if (pn > np)
			pn -= np;

		if (!player_is_comp(pn))
			return !!state->legs[pn - 1]->n_visits;
	}

	return false;
}

void user_undo()
{
	if (!first_user_has_thrown()) {
		oi();
		return;
	}

	if (state->num_darts) {
		state->num_darts = 0;
		struct leg *l = state_active_leg();
		scoreboard_set_player_avg(state->active_player,
			((double)(l->start - l->visits[l->n_visits-2].rem) /
				(l->n_visits - 1)));
		scoreboard_set_player_active(state->active_player);
		handle_next();
		return;
	}

	state->active_player = prev_throw_player();
	while (player_is_comp(state->active_player))
		undo_active();
	undo_active();

	draw_visits();
	handle_next();
}

void user_num_darts(int n)
{
	if (n < 1 || n > 3) {
		oi();
		return;
	}

	state->num_darts = n;
	update_player_avg(state->active_player, n);

	handle_next();
}

void match_mode_selected(int mode)
{
	if (mode < M_FIRST || mode > M_LAST) {
		oi();
		return;
	}

	if (match_opts) match_opts_free();
	match_opts = calloc(1, sizeof(*match_opts));
	match_opts->mode = mode;
	match_opts->start_pts = 501;
	match_opts->throws_first = 1;
	// names need to be freed if we stop using string literals
	if (mode == M_PVC) {
		match_opts->p1_name = "User";
		match_opts->p2_name = "Computer";
	} else if (mode == M_P) {
		match_opts->p1_name = "Player 1";
		match_opts->p2_name = NULL;
	} else if (mode == M_PVP) {
		match_opts->p1_name = "Player 1";
		match_opts->p2_name = "Player 2";
	}

	prompt_match_opts();
	prompt_flush();
}

void start_match()
{
	if (state) free_state(); // rematch gets us here
	++curr_match_id;

	state = calloc(1, sizeof(*state));
	state->mode = match_opts->mode;
	state->legs[0] = leg_init(match_opts->start_pts, match_opts->p1_name);
	state->legs[1] = leg_init(match_opts->start_pts,
		match_opts->p2_name ? match_opts->p2_name : "oi");

	show_player_info(1);
	update_player_name(1, state->legs[0]->name);
	update_player_rem(1, state->legs[0]->rem);
	update_player_avg(1, 0);

	if (state->mode != M_P) {
		show_player_info(2);
		update_player_name(2, state->legs[1]->name);
		update_player_rem(2, state->legs[1]->rem);
		update_player_avg(2, 0);
	}

	dom_enable_exit_dialogue(true);
	dom_add_class("#key-exit", "visible");
	draw_visits();
	handle_next();
}

void end_match()
{
	// clean up in case match was ended early
	svg_clear_points();
	prompt_set_input(NULL);
	scoreboard_set_player_active(-1);

	dom_remove_class("#key-exit", "visible");
	dom_enable_exit_dialogue(false);
	if (state) free_state();
	handle_next();
}