#ifndef __UCI_H_INC
#define __UCI_H_INC

#include "Tasks.h"

#define PS2(s) ([]{ static const char c[] PROGMEM = (s); return &c[0]; }())

typedef void uci_return;
typedef uci_return (*uci_handler)();

struct uci_cmd {
	const char* command;
	uci_handler handler;
};

void clear_line() {
	int peek = Serial.peek();
	if(peek == -1) return;

	do {
		peek = Serial.read();
	} while(peek != '\n');
}

uci_return uci_hello() {
	Serial.println(F("id name ArduChess\nid author Quinten Kock\nuciok"));
}

uci_return uci_unimpl() {
	Serial.println(F("Function not implemented yet"));
}

uci_return uci_unknown() {
	Serial.println(F("Not an UCI command"));
}

uci_return uci_perft() {
	int depth = Serial.parseInt();
	unsigned long result = pseudo_perft(depth);
	Serial.print(F("perft("));
	Serial.print(depth);
	Serial.print(F(") result: "));
	Serial.println(result);
}

const char UCI_COMMAND_uci[] PROGMEM = "uci";
const char UCI_COMMAND_debug[] PROGMEM = "debug";
const char UCI_COMMAND_isready[] PROGMEM = "isready";
const char UCI_COMMAND_setoption[] PROGMEM = "setoption";
const char UCI_COMMAND_ucinewgame[] PROGMEM = "ucinewgame";
const char UCI_COMMAND_position[] PROGMEM = "position";
const char UCI_COMMAND_go[] PROGMEM = "go";
const char UCI_COMMAND_stop[] PROGMEM = "stop";
const char UCI_COMMAND_ponderhit[] PROGMEM = "ponderhit";
const char UCI_COMMAND_quit[] PROGMEM = "quit";
const char UCI_COMMAND_bench[] PROGMEM = "bench";
const char UCI_COMMAND_perft[] PROGMEM = "perft";


const uci_cmd UCI_COMMANDS[] PROGMEM = {
	{UCI_COMMAND_uci, &uci_hello},
	{UCI_COMMAND_debug, &uci_unimpl},
	{UCI_COMMAND_isready, &uci_unimpl},
	{UCI_COMMAND_setoption, &uci_unimpl},
	{UCI_COMMAND_ucinewgame, &uci_unimpl},
	{UCI_COMMAND_position, &uci_unimpl},
	{UCI_COMMAND_go, &uci_unimpl},
	{UCI_COMMAND_stop, &uci_unimpl},
	{UCI_COMMAND_ponderhit, &uci_unimpl},
	{UCI_COMMAND_quit, &uci_unimpl},
	{UCI_COMMAND_bench, &bench},
	{UCI_COMMAND_perft, &uci_perft},
};

const uci_cmd UCI_INVALID = {PS2(""), &uci_unknown};

uci_cmd get_uci_command(const char* command) {
	size_t command_num = sizeof(UCI_COMMANDS) / sizeof(uci_cmd);
	for(size_t i = 0; i < command_num; i++) {
		size_t ci = 0;
		uci_cmd to_try;
		memcpy_P(&to_try, &UCI_COMMANDS[i], sizeof(uci_cmd));
		while(true) {
			char reference = pgm_read_byte_near(to_try.command + ci);
			if(reference != command[ci]) {
				break;
			}
			if(command[ci] == '\0') {
				return to_try;
			}
			ci++;
		}
	}
	return UCI_INVALID;
}

String read_word() {
	int incoming = Serial.read();
	String str = String();
	do {
		if(incoming != -1) {
			str += (char)incoming;
		}
		incoming = Serial.read();
	} while(incoming != '\n' && incoming != ' ');
	return str;
}

uci_return handle_uci() {
	if(Serial.available()) {
		// There is input available; so likely a command
		String command = read_word();
		uci_cmd handler = get_uci_command(command.c_str());
		handler.handler();
		clear_line();
	}
}


#endif