/*
 * mbsync - mailbox synchronizer
 * Copyright (C) 2000-2002 Michael R. Elkins <me@mutt.org>
 * Copyright (C) 2002-2004 Oswald Buddenhagen <ossi@users.sf.net>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software Foundation,
 *  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 *
 * As a special exception, mbsync may be linked with the OpenSSL library,
 * despite that library's more restrictive license.
 */

#include "isync.h"

#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/wait.h>

int Pid;		/* for maildir and imap */
char Hostname[256];	/* for maildir */
const char *Home;	/* for config */

static void
version( void )
{
	puts( PACKAGE " " VERSION );
	exit( 0 );
}

static void
usage( int code )
{
	fputs(
PACKAGE " " VERSION " - mailbox synchronizer\n"
"Copyright (C) 2000-2002 Michael R. Elkins <me@mutt.org>\n"
"Copyright (C) 2002-2004 Oswald Buddenhagen <ossi@users.sf.net>\n"
"Copyright (C) 2004 Theodore Ts'o <tytso@mit.edu>\n"
"usage:\n"
" " EXE " [flags] {{channel[:box,...]|group} ...|-a}\n"
"  -a, --all		operate on all defined channels\n"
"  -l, --list		list mailboxes instead of syncing them\n"
"  -n, --new		propagate new messages\n"
"  -d, --delete		propagate message deletions\n"
"  -f, --flags		propagate message flag changes\n"
"  -N, --renew		propagate previously not propagated new messages\n"
"  -L, --pull		propagate from master to slave\n"
"  -H, --push		propagate from slave to master\n"
"  -C, --create		create mailboxes if nonexistent\n"
"  -X, --expunge		expunge	deleted messages\n"
"  -c, --config CONFIG	read an alternate config file (default: ~/." EXE "rc)\n"
"  -D, --debug		print debugging messages\n"
"  -V, --verbose		verbose mode (display network traffic)\n"
"  -q, --quiet		don't display progress info\n"
"  -v, --version		display version\n"
"  -h, --help		display this help message\n"
"\nIf neither --pull nor --push are specified, both are active.\n"
"If neither --new, --delete, --flags nor --renew are specified, all are active.\n"
"Direction and operation can be concatenated like --pull-new, etc.\n"
"--create and --expunge can be suffixed with -master/-slave. Read the man page.\n"
"\nSupported mailbox formats are: IMAP4rev1, Maildir\n"
"\nCompile time options:\n"
#if HAVE_LIBSSL
"  +HAVE_LIBSSL\n"
#else
"  -HAVE_LIBSSL\n"
#endif
	, code ? stderr : stdout );
	exit( code );
}

static void
crashHandler( int n )
{
	int dpid;
	char pbuf[10], pabuf[20];

	close( 0 );
	open( "/dev/tty", O_RDWR );
	dup2( 0, 1 );
	dup2( 0, 2 );
	fprintf( stderr, "*** " EXE " caught signal %d. Starting debugger ...\n", n );
	switch ((dpid = fork ())) {
	case -1:
		perror( "fork()" );
		break;
	case 0:
		sprintf( pbuf, "%d", Pid );
		sprintf( pabuf, "/proc/%d/exe", Pid );
		execlp( "gdb", "gdb", pabuf, pbuf, (char *)0 );
		perror( "execlp()" );
		_exit( 1 );
	default:
		waitpid( dpid, 0, 0 );
		break;
	}
	exit( 3 );
}

static int
matches( const char *t, const char *p )
{
	for (;;) {
		if (!*p)
			return !*t;
		if (*p == '*') {
			p++;
			do {
				if (matches( t, p ))
					return 1;
			} while (*t++);
			return 0;
		} else if (*p == '%') {
			p++;
			do {
				if (*t == '.' || *t == '/') /* this is "somewhat" hacky ... */
					return 0;
				if (matches( t, p ))
					return 1;
			} while (*t++);
			return 0;
		} else {
			if (*p != *t)
				return 0;
			p++, t++;
		}
	}
}

static string_list_t *
filter_boxes( string_list_t *boxes, string_list_t *patterns )
{
	string_list_t *nboxes = 0, *cpat;
	const char *ps;
	int not, fnot;

	for (; boxes; boxes = boxes->next) {
		fnot = 1;
		for (cpat = patterns; cpat; cpat = cpat->next) {
			ps = cpat->string;
			if (*ps == '!') {
				ps++;
				not = 1;
			} else
				not = 0;
			if (matches( boxes->string, ps )) {
				fnot = not;
				break;
			}
		}
		if (!fnot)
			add_string_list( &nboxes, boxes->string );
	}
	return nboxes;
}

static void
merge_actions( channel_conf_t *chan, int ops[], int have, int mask, int def )
{
	if (ops[M] & have) {
		chan->ops[M] &= ~mask;
		chan->ops[M] |= ops[M] & mask;
		chan->ops[S] &= ~mask;
		chan->ops[S] |= ops[S] & mask;
	} else if (!(chan->ops[M] & have)) {
		if (global_ops[M] & have) {
			chan->ops[M] |= global_ops[M] & mask;
			chan->ops[S] |= global_ops[S] & mask;
		} else {
			chan->ops[M] |= def;
			chan->ops[S] |= def;
		}
	}
}

int
main( int argc, char **argv )
{
	channel_conf_t *chan;
	store_conf_t *conf[2];
	group_conf_t *group;
	driver_t *driver[2];
	store_t *ctx[2];
	string_list_t *uboxes[2], *boxes[2], *mbox, *sbox, **mboxp, **sboxp, *cboxes, *chanptr;
	char *config = 0, *channame, *boxlist, *opt, *ochar;
	const char *names[2];
	int all = 0, list = 0, cops = 0, ops[2] = { 0, 0 }, guboxes[2];
	int oind, ret, op, multiple, pseudo = 0, t;

	gethostname( Hostname, sizeof(Hostname) );
	if ((ochar = strchr( Hostname, '.' )))
		*ochar = 0;
	Pid = getpid();
	if (!(Home = getenv("HOME"))) {
		fputs( "Fatal: $HOME not set\n", stderr );
		return 1;
	}
	arc4_init();

	for (oind = 1, ochar = 0; oind < argc; ) {
		if (!ochar || !*ochar) {
			if (argv[oind][0] != '-')
				break;
			if (argv[oind][1] == '-') {
				opt = argv[oind++] + 2;
				if (!*opt)
					break;
				if (!strcmp( opt, "config" )) {
					if (oind >= argc) {
						fprintf( stderr, "--config requires an argument.\n" );
						return 1;
					}
					config = argv[oind++];
				} else if (!memcmp( opt, "config=", 7 ))
					config = opt + 7;
				else if (!strcmp( opt, "all" ))
					all = 1;
				else if (!strcmp( opt, "list" ))
					list = 1;
				else if (!strcmp( opt, "help" ))
					usage( 0 );
				else if (!strcmp( opt, "version" ))
					version();
				else if (!strcmp( opt, "quiet" )) {
					if (DFlags & QUIET)
						DFlags |= VERYQUIET;
					else
						DFlags |= QUIET;
				} else if (!strcmp( opt, "verbose" ))
					DFlags |= VERBOSE | QUIET;
				else if (!strcmp( opt, "debug" ))
					DFlags |= DEBUG | QUIET;
				else if (!strcmp( opt, "pull" ))
					cops |= XOP_PULL, ops[M] |= XOP_HAVE_TYPE;
				else if (!strcmp( opt, "push" ))
					cops |= XOP_PUSH, ops[M] |= XOP_HAVE_TYPE;
				else if (!memcmp( opt, "create", 6 )) {
					opt += 6;
					op = OP_CREATE|XOP_HAVE_CREATE;
				  lcop:
					if (!*opt)
						cops |= op;
					else if (!strcmp( opt, "-master" ))
						ops[M] |= op, ochar++;
					else if (!strcmp( opt, "-slave" ))
						ops[S] |= op, ochar++;
					else
						goto badopt;
					ops[M] |= op & (XOP_HAVE_CREATE|XOP_HAVE_EXPUNGE);
				} else if (!memcmp( opt, "expunge", 7 )) {
					opt += 7;
					op = OP_EXPUNGE|XOP_HAVE_EXPUNGE;
					goto lcop;
				} else if (!strcmp( opt, "no-expunge" ))
					ops[M] |= XOP_HAVE_EXPUNGE;
				else if (!strcmp( opt, "no-create" ))
					ops[M] |= XOP_HAVE_CREATE;
				else if (!strcmp( opt, "full" ))
					ops[M] |= XOP_HAVE_TYPE|XOP_PULL|XOP_PUSH;
				else if (!strcmp( opt, "noop" ))
					ops[M] |= XOP_HAVE_TYPE;
				else if (!memcmp( opt, "pull", 4 )) {
					op = XOP_PULL;
				  lcac:
					opt += 4;
					if (!*opt)
						cops |= op;
					else if (*opt == '-') {
						opt++;
						goto rlcac;
					} else
						goto badopt;
				} else if (!memcmp( opt, "push", 4 )) {
					op = XOP_PUSH;
					goto lcac;
				} else {
					op = 0;
				  rlcac:
					if (!strcmp( opt, "new" ))
						op |= OP_NEW;
					else if (!strcmp( opt, "renew" ))
						op |= OP_RENEW;
					else if (!strcmp( opt, "delete" ))
						op |= OP_DELETE;
					else if (!strcmp( opt, "flags" ))
						op |= OP_FLAGS;
					else {
					  badopt:
						fprintf( stderr, "Unknown option '%s'\n", argv[oind - 1] );
						return 1;
					}
					switch (op & XOP_MASK_DIR) {
					case XOP_PULL: ops[S] |= op & OP_MASK_TYPE; break;
					case XOP_PUSH: ops[M] |= op & OP_MASK_TYPE; break;
					default: cops |= op; break;
					}
					ops[M] |= XOP_HAVE_TYPE;
				}
				continue;
			}
			ochar = argv[oind++] + 1;
			if (!*ochar) {
				fprintf( stderr, "Invalid option '-'\n" );
				return 1;
			}
		}
		switch (*ochar++) {
		case 'a':
			all = 1;
			break;
		case 'l':
			list = 1;
			break;
		case 'c':
			if (*ochar == 'T') {
				ochar++;
				pseudo = 1;
			}
			if (oind >= argc) {
				fprintf( stderr, "-c requires an argument.\n" );
				return 1;
			}
			config = argv[oind++];
			break;
		case 'C':
			op = OP_CREATE|XOP_HAVE_CREATE;
		  cop:
			if (*ochar == 'm')
				ops[M] |= op, ochar++;
			else if (*ochar == 's')
				ops[S] |= op, ochar++;
			else if (*ochar == '-')
				ochar++;
			else
				cops |= op;
			ops[M] |= op & (XOP_HAVE_CREATE|XOP_HAVE_EXPUNGE);
			break;
		case 'X':
			op = OP_EXPUNGE|XOP_HAVE_EXPUNGE;
			goto cop;
		case 'F':
			cops |= XOP_PULL|XOP_PUSH;
		case '0':
			ops[M] |= XOP_HAVE_TYPE;
			break;
		case 'n':
		case 'd':
		case 'f':
		case 'N':
			--ochar;
			op = 0;
		  cac:
			for (;; ochar++) {
				if (*ochar == 'n')
					op |= OP_NEW;
				else if (*ochar == 'd')
					op |= OP_DELETE;
				else if (*ochar == 'f')
					op |= OP_FLAGS;
				else if (*ochar == 'N')
					op |= OP_RENEW;
				else
					break;
			}
			if (op & OP_MASK_TYPE)
				switch (op & XOP_MASK_DIR) {
				case XOP_PULL: ops[S] |= op & OP_MASK_TYPE; break;
				case XOP_PUSH: ops[M] |= op & OP_MASK_TYPE; break;
				default: cops |= op; break;
				}
			else
				cops |= op;
			ops[M] |= XOP_HAVE_TYPE;
			break;
		case 'L':
			op = XOP_PULL;
			goto cac;
		case 'H':
			op = XOP_PUSH;
			goto cac;
		case 'q':
			if (DFlags & QUIET)
				DFlags |= VERYQUIET;
			else
				DFlags |= QUIET;
			break;
		case 'V':
			DFlags |= VERBOSE | QUIET;
			break;
		case 'D':
			DFlags |= DEBUG | QUIET;
			break;
		case 'J':
			DFlags |= KEEPJOURNAL;
			break;
		case 'v':
			version();
		case 'h':
			usage( 0 );
		default:
			fprintf( stderr, "Unknown option '-%c'\n", *(ochar - 1) );
			return 1;
		}
	}

	if (DFlags & DEBUG) {
		signal( SIGSEGV, crashHandler );
		signal( SIGBUS, crashHandler );
		signal( SIGILL, crashHandler );
	}

	if (merge_ops( cops, ops ))
		return 1;

	if (load_config( config, pseudo ))
		return 1;

	if (!all && !argv[oind]) {
		fputs( "No channel specified. Try '" EXE " -h'\n", stderr );
		return 1;
	}
	if (!channels) {
		fputs( "No channels defined. Try 'man " EXE "'\n", stderr );
		return 1;
	}

	ret = 0;
	chan = channels;
	chanptr = 0;
	ctx[M] = ctx[S] = 0;
	conf[M] = conf[S] = 0;	/* make-gcc-happy */
	driver[M] = driver[S] = 0;	/* make-gcc-happy */
	guboxes[M] = guboxes[S] = 0;
	uboxes[M] = uboxes[S] = 0;
	if (all)
		multiple = channels->next != 0;
	else if (argv[oind + 1])
		multiple = 1;
	else {
		multiple = 0;
		for (group = groups; group; group = group->next)
			if (!strcmp( group->name, argv[oind] )) {
				multiple = 1;
				break;
			}
	}
	for (;;) {
		boxlist = 0;
		if (!all) {
			if (chanptr)
				channame = chanptr->string;
			else {
				for (group = groups; group; group = group->next)
					if (!strcmp( group->name, argv[oind] )) {
						chanptr = group->channels;
						channame = chanptr->string;
						goto gotgrp;
					}
				channame = argv[oind];
			  gotgrp: ;
			}
			if ((boxlist = strchr( channame, ':' )))
				*boxlist++ = 0;
			for (chan = channels; chan; chan = chan->next)
				if (!strcmp( chan->name, channame ))
					goto gotchan;
			fprintf( stderr, "No channel or group named '%s' defined.\n", channame );
			ret = 1;
			goto gotnone;
		  gotchan: ;
		}
		merge_actions( chan, ops, XOP_HAVE_TYPE, OP_MASK_TYPE, OP_MASK_TYPE );
		merge_actions( chan, ops, XOP_HAVE_CREATE, OP_CREATE, 0 );
		merge_actions( chan, ops, XOP_HAVE_EXPUNGE, OP_EXPUNGE, 0 );

		boxes[M] = boxes[S] = cboxes = 0;
		/* possible todo: handle master <-> slave swaps */
		for (t = 0; t < 2; t++) {
			if (ctx[t]) {
				if (conf[t] == chan->stores[t])
					continue;
				free_string_list( uboxes[t] );
				uboxes[t] = 0;
				guboxes[t] = 0;
				if (conf[t]->driver != chan->stores[t]->driver) {
					driver[t]->close_store( ctx[t] );
					ctx[t] = 0;
				}
			}
			conf[t] = chan->stores[t];
			driver[t] = conf[t]->driver;
			if (!(ctx[t] = driver[t]->open_store( chan->stores[t], ctx[t] ))) {
				ret = 1;
				goto next;
			}
		}
		info( "Channel %s\n", chan->name );
		if (list && multiple)
			printf( "%s:\n", chan->name );
		if (boxlist) {
			for (boxlist = strtok( boxlist, ",\n" ); boxlist; boxlist = strtok( 0, ",\n" ))
				if (list)
					puts( boxlist );
				else {
					names[M] = names[S] = boxlist;
					switch (sync_boxes( ctx, names, chan )) {
					case SYNC_BAD(M): t = M; goto screwt;
					case SYNC_BAD(S): t = S; goto screwt;
					case SYNC_FAIL: ret = 1;
					}
				}
		} else if (chan->patterns) {
			for (t = 0; t < 2; t++) {
				if (!guboxes[t]) {
					if (driver[t]->list( ctx[t], &uboxes[t] ) != DRV_OK) {
					  screwt:
						driver[t]->close_store( ctx[t] );
						free_string_list( uboxes[t] );
						uboxes[t] = 0;
						guboxes[t] = 0;
						ctx[t] = 0;
						ret = 1;
						goto next;
					} else {
						guboxes[t] = 1;
						if (ctx[t]->conf->map_inbox)
							add_string_list( &uboxes[t], ctx[t]->conf->map_inbox );
					}
				}
				boxes[t] = filter_boxes( uboxes[t], chan->patterns );
			}
			for (mboxp = &boxes[M]; (mbox = *mboxp); ) {
				for (sboxp = &boxes[S]; (sbox = *sboxp); sboxp = &sbox->next)
					if (!strcmp( sbox->string, mbox->string )) {
						*sboxp = sbox->next;
						free( sbox );
						*mboxp = mbox->next;
						mbox->next = cboxes;
						cboxes = mbox;
						goto gotdupe;
					}
				mboxp = &mbox->next;
			  gotdupe: ;
			}
			for (mbox = cboxes; mbox; mbox = mbox->next)
				if (list)
					puts( mbox->string );
				else {
					names[M] = names[S] = mbox->string;
					switch (sync_boxes( ctx, names, chan )) {
					case SYNC_BAD(M): t = M; goto screwt;
					case SYNC_BAD(S): t = S; goto screwt;
					case SYNC_FAIL: ret = 1;
					}
				}
			for (t = 0; t < 2; t++)
				if ((chan->ops[1-t] & OP_MASK_TYPE) && (chan->ops[1-t] & OP_CREATE)) {
					for (mbox = boxes[t]; mbox; mbox = mbox->next)
						if (list)
							puts( mbox->string );
						else {
							names[M] = names[S] = mbox->string;
							switch (sync_boxes( ctx, names, chan )) {
							case SYNC_BAD(M): t = M; goto screwt;
							case SYNC_BAD(S): t = S; goto screwt;
							case SYNC_FAIL: ret = 1;
							}
						}
				}
		} else
			if (list)
				printf( "%s <=> %s\n", chan->boxes[M], chan->boxes[S] );
			else
				switch (sync_boxes( ctx, chan->boxes, chan )) {
				case SYNC_BAD(M): t = M; goto screwt;
				case SYNC_BAD(S): t = S; goto screwt;
				case SYNC_FAIL: ret = 1;
				}

	  next:
		free_string_list( cboxes );
		free_string_list( boxes[M] );
		free_string_list( boxes[S] );
		if (all) {
			if (!(chan = chan->next))
				break;
		} else {
			if (chanptr && (chanptr = chanptr->next))
				continue;
		  gotnone:
			if (!argv[++oind])
				break;
		}
	}
	free_string_list( uboxes[S] );
	if (ctx[S])
		driver[S]->close_store( ctx[S] );
	free_string_list( uboxes[M] );
	if (ctx[M])
		driver[M]->close_store( ctx[M] );

	return ret;
}