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

#include "irc.h"
#include "numerics.h"

#ifdef __ATARI__
#include <atari.h>
#include <conio.h>
#include "conio.h"
#include "nio.h"
#else
#define CH_EOL '|'
unsigned char rx_buf[MAX_IRC_MSG_LEN];      // RX buffer.
unsigned short bw=0;            // # of bytes waiting.
#endif

#define MAX_MSG 512

char *msg_src, *msg_cmd, *msg_dest, *msg_text;
char *msg_args[MAX_MSG_ARGS];
int msg_argcount;

static char msgbuf[MAX_MSG] = { 0 };
static char *msg; /* with source removed */
static int msgbuf_len = 0, msg_len = 0;

static int joined = 0;

#ifdef __ATARI__
static void join_channel(void) {
	ui_print("Joining channel...\n");
	txbuf_set_str("JOIN ");
	txbuf_append_str(channel);
	txbuf_append_str("\n");
	txbuf_send();
	joined = 1;
}

static void do_pong(void) {
	ui_putchar(CH_EOL);
	ui_print("PING/PONG\n"); /* make hiding this a preference, or just ditch it */
	txbuf_set_str("PONG ");
	txbuf_append_str(msg_args[0]);
	txbuf_send();
}

static void do_privmsg(void) {
	static char chan;

	chan = (*msg_dest == '#');

	if(chan) {
		ui_putchar('<');
	} else {
		ui_putchar('*');
	}

	ui_print(msg_src);

	if(chan) {
		ui_putchar('>');
	} else {
		ui_putchar('*');
	}

	ui_putchar(' ');
	ui_print(msg_text);
}

/* numerics call this with arg==1, since arg 0 is always our nick.
   other commands call with arg==0 to print everything.
 */
static void do_catchall(int arg) {
	if(msg_src) {
		ui_print(msg_src);
		ui_putchar(' ');
	}

	ui_print(msg_cmd);

	for(; arg < msg_argcount; arg++) {
		ui_putchar(' ');
		ui_print(msg_args[arg]);
	}

	if(msg_text) {
		ui_putchar(' ');
		ui_print(msg_text);
	}
}

static void do_numeric(void) {
	unsigned int num = atoi(msg_cmd);

	switch(num) {
		/* don't print these, but they do trigger an action */
		case RPL_MOTDSTART:
		case RPL_ENDOFMOTD:
			if(!joined) join_channel();
			break;

		case RPL_TOPIC:
			ui_print("Topic for ");
			ui_print(msg_args[1]);
			ui_print(": ");
			ui_print(msg_text);
			break;

		case RPL_TOPICWHOTIME:
			ui_print("Topic set by: ");
			ui_print(msg_args[1]);
			ui_putchar('\n');
			break;

		default:
			do_catchall(1);
			break;
	}
}

static void invalid_msg(char type) {
	ui_print("??? unknown, type ");
	ui_putchar(type);
	ui_putchar('\n');
}
#else
static void do_pong(void) { }
static void invalid_msg(char type) {
	printf("??? unknown, type %c\n", type);
}
#endif

/* msgbuf contains a complete message from the server, whose
   length is msgbuf_len. the last character *must* be CH_EOL,
   and the last argument ends with CH_EOL. */
static void parse_msg(void) {
	char *p;

#ifndef __ATARI__
	printf("\ngot message:\n");
	for(msg = msgbuf; *msg != CH_EOL; msg++)
		putchar(*msg);
	putchar('\n');
	putchar('\n');
#endif

	msg_cmd = msg_text = msg_src = msg_dest = 0;
	msg = msgbuf;

	/* ignore empty message */
	if(*msg == CH_EOL) return;

	/* if there's a final multiword arg... */
	/* FIXME: channel names can have colons, which breaks this... */
	p = strstr(msg + 1, " :"); /* +1 to skip leading colon in msg source */
	if(p) {
		msg_text = p + 2;
		*p = 0;
	}

	/* first token is either the source (with a :) or a command (without) */
	p = strtok(msg, " ");
	if(!p) {
		invalid_msg('1');
		return;
	}

	if(*p == ':') {
		msg_src = p; /* generally :irc.example.com or :nick!user@host */
		msg_cmd = strtok(0, " ");
	} else {
		msg_src = 0; /* no source supplied */
		msg_cmd = p;
	}

	if(!msg_cmd) {
		invalid_msg('2');
		return;
	}

	/* special case for ping, treat as 1 arg, even if it has space and no : */
	if(streq_i(msg_cmd, "PING")) {
		msg_argcount = 1;
		msg_args[0] = msg_cmd + 6;
		do_pong();
		return;
	} else {
		for(msg_argcount = 0; msg_argcount < MAX_MSG_ARGS; msg_argcount++) {
			p = strtok(0, " ");
			if(p) {
				msg_args[msg_argcount] = p;
			} else {
				break;
			}
		}
	}
	if(msg_argcount) msg_dest = msg_args[0];

	if(msg_src) {
		if((p = strstr(msg_src, "!"))) {
			msg_src++;
			*p = '\0';
		} else {
			msg_src = 0;
		}
	}

#ifdef __ATARI__
	OS.crsinh = 1;
	ui_start_msg();
	if(streq_i(msg_cmd, "PRIVMSG")) {
		do_privmsg();
	} else if(isdigit(msg_cmd[0])) {
		do_numeric();
	} else {
		do_catchall(0);
	}
	ui_end_msg();
#else
	{
		int i;
		printf("src: %s\n", msg_src ? msg_src : "<none>");
		printf("cmd: %s\n", msg_cmd ? msg_cmd : "<none>");
		printf("args: %d\n", msg_argcount);
		for(i = 0; i < msg_argcount; i++)
			printf("  %d: %s\n", i, msg_args[i]);
		printf("text: %s\n", msg_text ? msg_text : "<none>");
	}
#endif
}

static void irc_parse(void) {
	int i;
	char *p = rx_buf;

#ifndef __ATARI__
	printf("irc_parse() called, bw == %d\n", bw);
#endif

	for(i = 0; i < bw; i++) {
		msgbuf[msgbuf_len] = *p;
		if(*p == CH_EOL) {
			msgbuf[msgbuf_len + 1] = '\0';
			parse_msg();
			msgbuf_len = 0;
		} else {
			msgbuf_len++;
		}
		p++;
	}
}

#ifdef __ATARI__
int irc_read(void) {
	if(!trip) return 1;

	err = nstatus(url);

	if(err == 136) {
		ui_print("Disconnected, press any key...\n");
		cgetc();
		return 0;
	} else if(err != 1) {
		print_error(err);
		return 0;
	}

	// Get # of bytes waiting, no more than size of rx_buf
	bw = OS.dvstat[1] * 256 + OS.dvstat[0];

	if(bw > sizeof(rx_buf))
		bw = sizeof(rx_buf);

	if(bw > 0) {
      err = nread(url, rx_buf, bw);
		if(err != 1) {
			ui_print("READ ERROR: ");
			print_error(err);
			return 0;
		}

		trip = 0;
		PIA.pactl |= 1; // Flag interrupt as serviced, ready for next one.

		irc_parse();
	}

	return 1;
}

/* modern.ircdocs.horse say to do this IMMEDIATELY upon TCP
   connection, without waiting for anything from the server. */
void irc_register(void) {
	txbuf_init();
	txbuf_append_str("USER ");
	txbuf_append_str(usernick); /* local (UNIX) username, just use the nick */
	txbuf_append_str(" 0 * :FujiNetChat User\n"); /* "real" name (make it a pref?) */
	txbuf_send();

	txbuf_init();
	txbuf_append_str("NICK ");
	txbuf_append_str(usernick);
	txbuf_append_str("\n");
	txbuf_send();
}

/* only exits on error (e.g. connection closed, which might be via /QUIT). */
void irc_loop(void) {
	while(1) {
		if(!irc_read()) return;

		if(kbhit())
			if(joined)
				ui_keystroke();
			else join_channel();
	}
}

#else // !defined(__ATARI__)
/* parsetest */
int main(int argc, char **argv) {
	strcpy((char *)rx_buf, argv[1]);
	bw = strlen(rx_buf);
	irc_parse();
	/*
	*/
	return 0;
}
#endif