#include "web_control.h"
#include "web_prompt.h"
#include "web_match.h"
#include "web_scoreboard.h"

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

#include <emscripten/emscripten.h>

struct prompt_state {
	char *msgl, *input, *msgr;
};

struct prompt_state prompt_buffered, prompt_flushed;

enum prompt_mode pm;

static inline void buffer_str(char *str, char **buffer, char *flushed)
{
	if (str == *buffer || (str && *buffer && !strcmp(str, *buffer)))
		return;

	if (*buffer && *buffer != flushed)
		free(*buffer);

	*buffer = str ? strdup(str) : NULL;
}

void prompt_set_msgl(char *str)
{
	buffer_str(str, &prompt_buffered.msgl, prompt_flushed.msgl);
}

void prompt_set_msgr(char *str)
{
	buffer_str(str, &prompt_buffered.msgr, prompt_flushed.msgr);
}

void prompt_set_input(char *str)
{
	buffer_str(str, &prompt_buffered.input, prompt_flushed.input);
}

static inline bool buffered_str_changed(char *buffered, char *flushed)
{
	return (!buffered != !flushed) ||
		(buffered && flushed && strcmp(buffered, flushed));
}

static inline void free_flushed_str(char *flushed, char *buffered)
{
	if (flushed && flushed != buffered)
		free(flushed);
}

void prompt_flush()
{
	if (buffered_str_changed(prompt_buffered.msgl, prompt_flushed.msgl))
		EM_ASM({elemSetContent($0, $1)},
			"#prompt-msg-l", prompt_buffered.msgl);
	if (buffered_str_changed(prompt_buffered.msgr, prompt_flushed.msgr))
		EM_ASM({elemSetContent($0, $1)},
			"#prompt-msg-r", prompt_buffered.msgr);
	if (buffered_str_changed(prompt_buffered.input, prompt_flushed.input))
		EM_ASM({elemSetContent($0, $1)},
			"#prompt-input", prompt_buffered.input);

	free_flushed_str(prompt_flushed.msgl, prompt_buffered.msgl);
	free_flushed_str(prompt_flushed.msgr, prompt_buffered.msgr);
	free_flushed_str(prompt_flushed.input, prompt_buffered.input);

	prompt_flushed = prompt_buffered;
}

void set_prompt_mode(enum prompt_mode mode)
{
	pm = mode;

	if (pm != PM_DARTBOARD)
		EM_ASM({elemAddClass($0, $1)}, "#prompt", "active");
	else
		EM_ASM({elemRemoveClass($0, $1)}, "#prompt", "active");

	EM_ASM({setKeypad($0)}, pm == PM_DARTBOARD ? "dartboard" :
		pm == PM_SELECT_MODE ? "select_mode" : "default");
}

void prompt_visit()
{
	set_prompt_mode(PM_VISIT);
	prompt_set_msgl("Enter points:");
	prompt_set_msgr(NULL);
	EM_ASM({elemSetContent($0, $1)}, "#key-submit", "OK");
	EM_ASM({elemSetContent($0, $1)}, "#key-rem", "REMAINING");
}

void prompt_bot_visit()
{
	set_prompt_mode(PM_DARTBOARD);
	prompt_set_msgl("Bot is throwing…");
	prompt_set_msgr(NULL);
}

void prompt_num_darts()
{
	set_prompt_mode(PM_NUM_DARTS);
	prompt_set_msgl("Darts needed?");
	prompt_set_msgr(NULL);
	EM_ASM({elemSetContent($0, $1)}, "#key-submit", "OK");
	EM_ASM({elemSetContent($0, $1)}, "#key-rem", "REMAINING");
}

void prompt_end_match()
{
	EM_ASM(setPlayerActive()); // sets all inactive
	set_prompt_mode(PM_END_MATCH);
	prompt_set_msgl(
		state->mode == M_PVC && state->legs[1]->rem <= 0 ? "Bot wins. :(" :
			"You win! :)");
	prompt_set_msgr(NULL);
	EM_ASM({elemSetContent($0, $1)}, "#key-submit", "OK");
	EM_ASM({elemSetContent($0, $1)}, "#key-rem", "REMATCH");
}

void prompt_select_mode()
{
	for (int pn = 1; pn < 3; ++pn) {
		EM_ASM({hidePlayerInfo($0)}, pn);
		clear_player_info(pn);
	}
	EM_ASM({elemSetContent($0, $1)}, "#visits", NULL);

	set_prompt_mode(PM_SELECT_MODE);
	prompt_set_msgl("Select match mode:");
	prompt_set_msgr(NULL);
}

bool is_key_active(char *k)
{
	char sel[64];
	sprintf(sel, "#key-%s", k);
	return EM_ASM_INT({return elemHasClass($0, $1)}, sel, "active");
}

void toggle_key(char *k)
{
	char sel[64];
	sprintf(sel, "#key-%s", k);
	EM_ASM({elemToggleClass($0, $1)}, sel, "active");
}

void deactivate_key(char *k)
{
	char sel[64];
	sprintf(sel, "#key-%s", k);
	EM_ASM({elemRemoveClass($0, $1)}, sel, "active");
}

char *prompt_get()
{
	return (char *)EM_ASM_INT({return elemGetContent($0)}, "#prompt-input");
}

void prompt_handle_pre(char *command)
{
	if (pm == PM_DARTBOARD)
		return;

	EM_ASM(clearOi());

	if ((pm == PM_VISIT || pm == PM_NUM_DARTS || pm == PM_END_MATCH) &&
		strcmp(command, "undo"))
		deactivate_key("undo");

	if (pm == PM_END_MATCH && strcmp(command, "rem"))
		deactivate_key("rem");

	if (pm == PM_END_MATCH && strcmp(command, "submit"))
		deactivate_key("submit");
}

void prompt_handle_on_change()
{
	prompt_flush();

	if (pm != PM_VISIT)
		return;

	char *str = prompt_get();
	update_user_rem_from_pts(atoi(str));
	free(str);
}

void prompt_handle_append(char *data)
{
	if (pm != PM_SELECT_MODE && pm != PM_VISIT && pm != PM_NUM_DARTS)
		return;

	char *str = prompt_get();
	size_t len_str = strlen(str);
	size_t len_data = strlen(data);
	if (len_str < 3) {
		str = realloc(str, len_str + len_data + 1);
		memcpy(str + len_str, data, len_data + 1);
		prompt_set_input(str);
		prompt_handle_on_change();
	}
	free(str);
}

void prompt_handle_backspace()
{
	if (pm == PM_DARTBOARD)
		return;

	char *str = prompt_get();
	size_t len_str = strlen(str);
	if (len_str > 0) {
		str[len_str-1] = 0;
		prompt_set_input(str);
		prompt_handle_on_change();
	}
	free(str);
}

void prompt_handle_clear()
{
	if (pm == PM_DARTBOARD)
		return;

	prompt_set_input(NULL);
	prompt_handle_on_change();
}

void prompt_handle_submit()
{
	if (pm == PM_END_MATCH) {
		if (is_key_active("submit"))
			end_match();
		toggle_key("submit");
		return;
	}

	if (pm != PM_VISIT && pm != PM_NUM_DARTS && pm != PM_SELECT_MODE)
		return;

	char *str = prompt_get();
	prompt_handle_clear();
	if (*str) {
		if (pm == PM_VISIT)
			user_visit(atoi(str));
		else if (pm == PM_NUM_DARTS)
			user_num_darts(atoi(str));
		else if (pm == PM_SELECT_MODE)
			start_match(atoi(str));
	}

	free(str);
}

void prompt_handle_rem()
{
	if (pm == PM_END_MATCH) {
		if (is_key_active("rem"))
			start_match(state->mode);
		toggle_key("rem");
		return;
	}

	if (pm != PM_VISIT)
		return;

	char *str = prompt_get();
	prompt_handle_clear();
	if (*str)
		user_visit_to_rem(atoi(str));
	free(str);
}

void prompt_handle_undo()
{
	if (pm != PM_VISIT && pm != PM_NUM_DARTS && pm != PM_END_MATCH)
		return;

	prompt_handle_clear();
	if (is_key_active("undo"))
		user_undo();
	toggle_key("undo");
}

EMSCRIPTEN_KEEPALIVE
void prompt_handle(char *command, char *data)
{
	prompt_handle_pre(command);

	if (!strcmp(command, "append"))
		prompt_handle_append(data);
	else if (!strcmp(command, "backspace"))
		prompt_handle_backspace();
	else if (!strcmp(command, "clear"))
		prompt_handle_clear();
	else if (!strcmp(command, "submit"))
		prompt_handle_submit();
	else if (!strcmp(command, "rem"))
		prompt_handle_rem();
	else if (!strcmp(command, "undo"))
		prompt_handle_undo();
}