evolution/camel/camel-mime-message.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8; fill-column: 160 -*- */
/* camel-mime-message.c : class for a mime_message */

/* 
 * Authors: Bertrand Guiheneuf <bertrand@helixcode.com>
 *	    Michael Zucchi <notzed@ximian.com>
 *          Jeffrey Stedfast <fejj@ximian.com>
 *
 * Copyright 1999-2003 Ximian, Inc. (www.ximian.com)
 *
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of version 2 of the GNU General Public 
 * License as published by the Free Software Foundation.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

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

#include <gal/util/e-iconv.h>

#include <e-util/e-time-utils.h>

#include "camel-mime-message.h"
#include "camel-multipart.h"
#include "camel-stream-mem.h"
#include "camel-string-utils.h"
#include "camel-url.h"

#include "camel-stream-filter.h"
#include "camel-stream-null.h"
#include "camel-mime-filter-charset.h"
#include "camel-mime-filter-bestenc.h"

#define d(x)

/* these 2 below should be kept in sync */
typedef enum {
	HEADER_UNKNOWN,
	HEADER_FROM,
	HEADER_REPLY_TO,
	HEADER_SUBJECT,
	HEADER_TO,
	HEADER_RESENT_TO,
	HEADER_CC,
	HEADER_RESENT_CC,
	HEADER_BCC,
	HEADER_RESENT_BCC,
	HEADER_DATE,
	HEADER_MESSAGE_ID
} CamelHeaderType;

static char *header_names[] = {
	/* dont include HEADER_UNKNOWN string */
	"From", "Reply-To", "Subject", "To", "Resent-To", "Cc", "Resent-Cc",
	"Bcc", "Resent-Bcc", "Date", "Message-Id", NULL
};

static GHashTable *header_name_table;

static CamelMimePartClass *parent_class = NULL;

static char *recipient_names[] = {
	"To", "Cc", "Bcc", "Resent-To", "Resent-Cc", "Resent-Bcc", NULL
};

static ssize_t write_to_stream (CamelDataWrapper *data_wrapper, CamelStream *stream);
static void add_header (CamelMedium *medium, const char *name, const void *value);
static void set_header (CamelMedium *medium, const char *name, const void *value);
static void remove_header (CamelMedium *medium, const char *name);
static int construct_from_parser (CamelMimePart *, CamelMimeParser *);
static void unref_recipient (gpointer key, gpointer value, gpointer user_data);

/* Returns the class for a CamelMimeMessage */
#define CMM_CLASS(so) CAMEL_MIME_MESSAGE_CLASS (CAMEL_OBJECT_GET_CLASS(so))
#define CDW_CLASS(so) CAMEL_DATA_WRAPPER_CLASS (CAMEL_OBJECT_GET_CLASS(so))
#define CMD_CLASS(so) CAMEL_MEDIUM_CLASS (CAMEL_OBJECT_GET_CLASS(so))

static void
camel_mime_message_class_init (CamelMimeMessageClass *camel_mime_message_class)
{
	CamelDataWrapperClass *camel_data_wrapper_class = CAMEL_DATA_WRAPPER_CLASS (camel_mime_message_class);
	CamelMimePartClass *camel_mime_part_class = CAMEL_MIME_PART_CLASS (camel_mime_message_class);
	CamelMediumClass *camel_medium_class = CAMEL_MEDIUM_CLASS (camel_mime_message_class);
	int i;
	
	parent_class = CAMEL_MIME_PART_CLASS (camel_type_get_global_classfuncs (camel_mime_part_get_type ()));
	
	header_name_table = g_hash_table_new (camel_strcase_hash, camel_strcase_equal);
	for (i = 0;header_names[i]; i++)
		g_hash_table_insert (header_name_table, header_names[i], GINT_TO_POINTER(i+1));

	/* virtual method overload */
	camel_data_wrapper_class->write_to_stream = write_to_stream;
	camel_data_wrapper_class->decode_to_stream = write_to_stream;

	camel_medium_class->add_header = add_header;
	camel_medium_class->set_header = set_header;
	camel_medium_class->remove_header = remove_header;
	
	camel_mime_part_class->construct_from_parser = construct_from_parser;
}


static void
camel_mime_message_init (gpointer object, gpointer klass)
{
	CamelMimeMessage *mime_message = (CamelMimeMessage *)object;
	int i;
	
	mime_message->recipients =  g_hash_table_new (camel_strcase_hash, camel_strcase_equal);
	for (i=0;recipient_names[i];i++) {
		g_hash_table_insert(mime_message->recipients, recipient_names[i], camel_internet_address_new());
	}

	mime_message->subject = NULL;
	mime_message->reply_to = NULL;
	mime_message->from = NULL;
	mime_message->date = CAMEL_MESSAGE_DATE_CURRENT;
	mime_message->date_offset = 0;
	mime_message->date_received = CAMEL_MESSAGE_DATE_CURRENT;
	mime_message->date_received_offset = 0;
	mime_message->message_id = NULL;
}

static void           
camel_mime_message_finalize (CamelObject *object)
{
	CamelMimeMessage *message = CAMEL_MIME_MESSAGE (object);
	
	g_free (message->subject);
	
	g_free (message->message_id);
	
	if (message->reply_to)
		camel_object_unref ((CamelObject *)message->reply_to);
	
	if (message->from)
		camel_object_unref ((CamelObject *)message->from);
	
	g_hash_table_foreach (message->recipients, unref_recipient, NULL);
	g_hash_table_destroy (message->recipients);
}


CamelType
camel_mime_message_get_type (void)
{
	static CamelType camel_mime_message_type = CAMEL_INVALID_TYPE;
	
	if (camel_mime_message_type == CAMEL_INVALID_TYPE)	{
		camel_mime_message_type = camel_type_register (camel_mime_part_get_type(), "CamelMimeMessage",
							       sizeof (CamelMimeMessage),
							       sizeof (CamelMimeMessageClass),
							       (CamelObjectClassInitFunc) camel_mime_message_class_init,
							       NULL,
							       (CamelObjectInitFunc) camel_mime_message_init,
							       (CamelObjectFinalizeFunc) camel_mime_message_finalize);
	}
	
	return camel_mime_message_type;
}

static void
unref_recipient (gpointer key, gpointer value, gpointer user_data)
{
	camel_object_unref (CAMEL_OBJECT (value));
}

CamelMimeMessage *
camel_mime_message_new (void) 
{
	CamelMimeMessage *mime_message;
	mime_message = CAMEL_MIME_MESSAGE (camel_object_new (CAMEL_MIME_MESSAGE_TYPE));
	
	return mime_message;
}

/* **** Date: */

void
camel_mime_message_set_date (CamelMimeMessage *message,  time_t date, int offset)
{
	char *datestr;
	
	g_assert(message);
	
	if (date == CAMEL_MESSAGE_DATE_CURRENT) {
		struct tm local;
		int tz;
		
		date = time(0);
		e_localtime_with_offset(date, &local, &tz);
		offset = (((tz/60/60) * 100) + (tz/60 % 60));
	}
	message->date = date;
	message->date_offset = offset;
	
	datestr = camel_header_format_date (date, offset);
	CAMEL_MEDIUM_CLASS (parent_class)->set_header ((CamelMedium *)message, "Date", datestr);
	g_free (datestr);
}

time_t
camel_mime_message_get_date (CamelMimeMessage *msg, int *offset)
{
	if (offset)
		*offset = msg->date_offset;
	
	return msg->date;
}

time_t
camel_mime_message_get_date_received (CamelMimeMessage *msg, int *offset)
{
	if (msg->date_received == CAMEL_MESSAGE_DATE_CURRENT) {
		const char *received;
		
		received = camel_medium_get_header ((CamelMedium *)msg, "received");
		if (received)
			received = strrchr (received, ';');
		if (received)
			msg->date_received = camel_header_decode_date (received + 1, &msg->date_received_offset);
	}
	
	if (offset)
		*offset = msg->date_received_offset;
	
	return msg->date_received;
}

/* **** Message-Id: */

void
camel_mime_message_set_message_id (CamelMimeMessage *mime_message, const char *message_id)
{
	char *id;
	
	g_assert (mime_message);
	
	g_free (mime_message->message_id);
	
	if (message_id) {
		id = g_strstrip (g_strdup (message_id));
	} else {
		id = camel_header_msgid_generate ();
	}
	
	mime_message->message_id = id;
	id = g_strdup_printf ("<%s>", mime_message->message_id);
	CAMEL_MEDIUM_CLASS (parent_class)->set_header (CAMEL_MEDIUM (mime_message), "Message-Id", id);
	g_free (id);
}

const char *
camel_mime_message_get_message_id (CamelMimeMessage *mime_message)
{
	g_assert (mime_message);
	
	return mime_message->message_id;
}

/* **** Reply-To: */

void
camel_mime_message_set_reply_to (CamelMimeMessage *msg, const CamelInternetAddress *reply_to)
{
	char *addr;
	
	g_assert(msg);
	
	if (msg->reply_to) {
		camel_object_unref ((CamelObject *)msg->reply_to);
		msg->reply_to = NULL;
	}
	
	if (reply_to == NULL) {
		CAMEL_MEDIUM_CLASS (parent_class)->remove_header (CAMEL_MEDIUM (msg), "Reply-To");
		return;
	}
	
	msg->reply_to = (CamelInternetAddress *)camel_address_new_clone ((CamelAddress *)reply_to);
	addr = camel_address_encode ((CamelAddress *)msg->reply_to);
	CAMEL_MEDIUM_CLASS (parent_class)->set_header (CAMEL_MEDIUM (msg), "Reply-To", addr);
	g_free (addr);
}

const CamelInternetAddress *
camel_mime_message_get_reply_to (CamelMimeMessage *mime_message)
{
	g_assert (mime_message);
	
	/* TODO: ref for threading? */
	
	return mime_message->reply_to;
}

/* **** Subject: */

void
camel_mime_message_set_subject (CamelMimeMessage *mime_message, const char *subject)
{
	char *text;
	
	g_assert(mime_message);
	
	g_free (mime_message->subject);
	mime_message->subject = g_strstrip (g_strdup (subject));
	text = camel_header_encode_string((unsigned char *)mime_message->subject);
	CAMEL_MEDIUM_CLASS(parent_class)->set_header(CAMEL_MEDIUM (mime_message), "Subject", text);
	g_free (text);
}

const char *
camel_mime_message_get_subject (CamelMimeMessage *mime_message)
{
	g_assert(mime_message);
	
	return mime_message->subject;
}

/* *** From: */

/* Thought: Since get_from/set_from are so rarely called, it is probably not useful
   to cache the from (and reply_to) addresses as InternetAddresses internally, we
   could just get it from the headers and reprocess every time. */
void
camel_mime_message_set_from (CamelMimeMessage *msg, const CamelInternetAddress *from)
{
	char *addr;
	
	g_assert(msg);
	
	if (msg->from) {
		camel_object_unref((CamelObject *)msg->from);
		msg->from = NULL;
	}
	
	if (from == NULL || camel_address_length((CamelAddress *)from) == 0) {
		CAMEL_MEDIUM_CLASS(parent_class)->remove_header(CAMEL_MEDIUM(msg), "From");
		return;
	}
	
	msg->from = (CamelInternetAddress *)camel_address_new_clone((CamelAddress *)from);
	addr = camel_address_encode((CamelAddress *)msg->from);
	CAMEL_MEDIUM_CLASS (parent_class)->set_header(CAMEL_MEDIUM(msg), "From", addr);
	g_free(addr);
}

const CamelInternetAddress *
camel_mime_message_get_from (CamelMimeMessage *mime_message)
{
	g_assert (mime_message);
	
	/* TODO: we should really ref this for multi-threading to work */
	
	return mime_message->from;
}

/*  **** To: Cc: Bcc: */

void
camel_mime_message_set_recipients(CamelMimeMessage *mime_message, const char *type, const CamelInternetAddress *r)
{
	char *text;
	CamelInternetAddress *addr;
	
	g_assert(mime_message);
	
	addr = g_hash_table_lookup (mime_message->recipients, type);
	if (addr == NULL) {
		g_warning ("trying to set a non-valid receipient type: %s", type);
		return;
	}
	
	if (r == NULL || camel_address_length ((CamelAddress *)r) == 0) {
		camel_address_remove ((CamelAddress *)addr, -1);
		CAMEL_MEDIUM_CLASS (parent_class)->remove_header (CAMEL_MEDIUM (mime_message), type);
		return;
	}
	
	/* note this does copy, and not append (cat) */
	camel_address_copy ((CamelAddress *)addr, (const CamelAddress *)r);
	
	/* and sync our headers */
	text = camel_address_encode (CAMEL_ADDRESS (addr));
	CAMEL_MEDIUM_CLASS (parent_class)->set_header (CAMEL_MEDIUM (mime_message), type, text);
	g_free(text);
}

void
camel_mime_message_set_source (CamelMimeMessage *mime_message, const char *src)
{
	CamelURL *url;
	char *uri;
	
	g_assert (mime_message);
	
	url = camel_url_new (src, NULL);
	if (url) {
		uri = camel_url_to_string (url, CAMEL_URL_HIDE_ALL);
		camel_medium_add_header (CAMEL_MEDIUM (mime_message), "X-Evolution-Source", uri);
		g_free (uri);
		camel_url_free (url);
	}
}

const char *
camel_mime_message_get_source (CamelMimeMessage *mime_message)
{
	const char *src;
	
	g_assert(mime_message);
	
	src = camel_medium_get_header (CAMEL_MEDIUM (mime_message), "X-Evolution-Source");
	if (src) {
		while (*src && isspace ((unsigned) *src))
			++src;
	}
	return src;
}

const CamelInternetAddress *
camel_mime_message_get_recipients (CamelMimeMessage *mime_message, const char *type)
{
	g_assert(mime_message);
	
	return g_hash_table_lookup (mime_message->recipients, type);
}

/* mime_message */
static int
construct_from_parser (CamelMimePart *dw, CamelMimeParser *mp)
{
	char *buf;
	size_t len;
	int state;
	int ret;
	int err;

	d(printf("constructing mime-message\n"));

	d(printf("mime_message::construct_from_parser()\n"));

	/* let the mime-part construct the guts ... */
	ret = ((CamelMimePartClass *)parent_class)->construct_from_parser(dw, mp);

	if (ret == -1)
		return -1;

	/* ... then clean up the follow-on state */
	state = camel_mime_parser_step (mp, &buf, &len);
	switch (state) {
	case CAMEL_MIME_PARSER_STATE_EOF: case CAMEL_MIME_PARSER_STATE_FROM_END: /* these doesn't belong to us */
		camel_mime_parser_unstep (mp);
	case CAMEL_MIME_PARSER_STATE_MESSAGE_END:
		break;
	default:
		g_error ("Bad parser state: Expecing MESSAGE_END or EOF or EOM, got: %d", camel_mime_parser_state (mp));
		camel_mime_parser_unstep (mp);
		return -1;
	}

	d(printf("mime_message::construct_from_parser() leaving\n"));
	err = camel_mime_parser_errno(mp);
	if (err != 0) {
		errno = err;
		ret = -1;
	}

	return ret;
}

static ssize_t
write_to_stream (CamelDataWrapper *data_wrapper, CamelStream *stream)
{
	CamelMimeMessage *mm = CAMEL_MIME_MESSAGE (data_wrapper);
	
	/* force mandatory headers ... */
	if (mm->from == NULL) {
		/* FIXME: should we just abort?  Should we make one up? */
		g_warning ("No from set for message");
		camel_medium_set_header ((CamelMedium *)mm, "From", "");
	}
	if (!camel_medium_get_header ((CamelMedium *)mm, "Date"))
		camel_mime_message_set_date (mm, CAMEL_MESSAGE_DATE_CURRENT, 0);
	
	if (mm->subject == NULL)
		camel_mime_message_set_subject (mm, "No Subject");
	
	if (mm->message_id == NULL)
		camel_mime_message_set_message_id (mm, NULL);
	
	/* FIXME: "To" header needs to be set explicitly as well ... */
	
	if (!camel_medium_get_header ((CamelMedium *)mm, "Mime-Version"))
		camel_medium_set_header ((CamelMedium *)mm, "Mime-Version", "1.0");
	
	return CAMEL_DATA_WRAPPER_CLASS (parent_class)->write_to_stream (data_wrapper, stream);
}

/* FIXME: check format of fields. */
static gboolean
process_header (CamelMedium *medium, const char *name, const char *value)
{
	CamelHeaderType header_type;
	CamelMimeMessage *message = CAMEL_MIME_MESSAGE (medium);
	CamelInternetAddress *addr;
	const char *charset;
	
	header_type = (CamelHeaderType) g_hash_table_lookup (header_name_table, name);
	switch (header_type) {
	case HEADER_FROM:
		if (message->from)
			camel_object_unref (CAMEL_OBJECT (message->from));
		message->from = camel_internet_address_new ();
		camel_address_decode (CAMEL_ADDRESS (message->from), value);
		break;
	case HEADER_REPLY_TO:
		if (message->reply_to)
			camel_object_unref (CAMEL_OBJECT (message->reply_to));
		message->reply_to = camel_internet_address_new ();
		camel_address_decode (CAMEL_ADDRESS (message->reply_to), value);
		break;
	case HEADER_SUBJECT:
		g_free (message->subject);
		if (((CamelDataWrapper *) message)->mime_type) {
			charset = camel_content_type_param (((CamelDataWrapper *) message)->mime_type, "charset");
			charset = e_iconv_charset_name (charset);
		} else
			charset = NULL;
		message->subject = g_strstrip (camel_header_decode_string (value, charset));
		break;
	case HEADER_TO:
	case HEADER_CC:
	case HEADER_BCC:
	case HEADER_RESENT_TO:
	case HEADER_RESENT_CC:
	case HEADER_RESENT_BCC:
		addr = g_hash_table_lookup (message->recipients, name);
		if (value)
			camel_address_decode (CAMEL_ADDRESS (addr), value);
		else
			camel_address_remove (CAMEL_ADDRESS (addr), -1);
		break;
	case HEADER_DATE:
		if (value) {
			message->date = camel_header_decode_date (value, &message->date_offset);
		} else {
			message->date = CAMEL_MESSAGE_DATE_CURRENT;
			message->date_offset = 0;
		}
		break;
	case HEADER_MESSAGE_ID:
		g_free (message->message_id);
		if (value)
			message->message_id = camel_header_msgid_decode (value);
		else
			message->message_id = NULL;
		break;
	default:
		return FALSE;
	}
	
	return TRUE;
}

static void
set_header (CamelMedium *medium, const char *name, const void *value)
{
	process_header (medium, name, value);
	parent_class->parent_class.set_header (medium, name, value);
}

static void
add_header (CamelMedium *medium, const char *name, const void *value)
{
	/* if we process it, then it must be forced unique as well ... */
	if (process_header (medium, name, value))
		parent_class->parent_class.set_header (medium, name, value);
	else
		parent_class->parent_class.add_header (medium, name, value);
}

static void
remove_header (CamelMedium *medium, const char *name)
{
	process_header (medium, name, NULL);
	parent_class->parent_class.remove_header (medium, name);
}

typedef gboolean (*CamelPartFunc)(CamelMimeMessage *, CamelMimePart *, void *data);

static gboolean
message_foreach_part_rec (CamelMimeMessage *msg, CamelMimePart *part, CamelPartFunc callback, void *data)
{
	CamelDataWrapper *containee;
	int parts, i;
	int go = TRUE;
	
	if (callback (msg, part, data) == FALSE)
		return FALSE;
	
	containee = camel_medium_get_content_object (CAMEL_MEDIUM (part));
	
	if (containee == NULL)
		return go;
	
	/* using the object types is more accurate than using the mime/types */
	if (CAMEL_IS_MULTIPART (containee)) {
		parts = camel_multipart_get_number (CAMEL_MULTIPART (containee));
		for (i = 0; go && i < parts; i++) {
			CamelMimePart *part = camel_multipart_get_part (CAMEL_MULTIPART (containee), i);
			
			go = message_foreach_part_rec (msg, part, callback, data);
		}
	} else if (CAMEL_IS_MIME_MESSAGE (containee)) {
		go = message_foreach_part_rec (msg, (CamelMimePart *)containee, callback, data);
	}
	
	return go;
}

/* dont make this public yet, it might need some more thinking ... */
/* MPZ */
static void
camel_mime_message_foreach_part (CamelMimeMessage *msg, CamelPartFunc callback, void *data)
{
	message_foreach_part_rec (msg, (CamelMimePart *)msg, callback, data);
}

static gboolean
check_8bit (CamelMimeMessage *msg, CamelMimePart *part, void *data)
{
	CamelTransferEncoding encoding;
	int *has8bit = data;
	
	/* check this part, and stop as soon as we are done */
	encoding = camel_mime_part_get_encoding (part);
	
	*has8bit = encoding == CAMEL_TRANSFER_ENCODING_8BIT || encoding == CAMEL_TRANSFER_ENCODING_BINARY;
	
	return !(*has8bit);
}

gboolean
camel_mime_message_has_8bit_parts (CamelMimeMessage *msg)
{
	int has8bit = FALSE;
	
	camel_mime_message_foreach_part (msg, check_8bit, &has8bit);
	
	return has8bit;
}

/* finds the best charset and transfer encoding for a given part */
static CamelTransferEncoding
find_best_encoding (CamelMimePart *part, CamelBestencRequired required, CamelBestencEncoding enctype, char **charsetp)
{
	CamelMimeFilterCharset *charenc = NULL;
	CamelTransferEncoding encoding;
	CamelMimeFilterBestenc *bestenc;
	unsigned int flags, callerflags;
	CamelDataWrapper *content;
	CamelStreamFilter *filter;
	const char *charsetin = NULL;
	char *charset = NULL;
	CamelStream *null;
	int idb, idc = -1;
	gboolean istext;
	
	/* we use all these weird stream things so we can do it with streams, and
	   not have to read the whole lot into memory - although i have a feeling
	   it would make things a fair bit simpler to do so ... */
	
	d(printf("starting to check part\n"));
	
	content = camel_medium_get_content_object ((CamelMedium *)part);
	if (content == NULL) {
		/* charset might not be right here, but it'll get the right stuff
		   if it is ever set */
		*charsetp = NULL;
		return CAMEL_TRANSFER_ENCODING_DEFAULT;
	}
	
	istext = camel_content_type_is (((CamelDataWrapper *) part)->mime_type, "text", "*");
	if (istext) {
		flags = CAMEL_BESTENC_GET_CHARSET | CAMEL_BESTENC_GET_ENCODING;
		enctype |= CAMEL_BESTENC_TEXT;
	} else {
		flags = CAMEL_BESTENC_GET_ENCODING;
	}
	
	/* when building the message, any encoded parts are translated already */
	flags |= CAMEL_BESTENC_LF_IS_CRLF;
	/* and get any flags the caller passed in */
	callerflags = (required & CAMEL_BESTENC_NO_FROM);
	flags |= callerflags;
	
	/* first a null stream, so any filtering is thrown away; we only want the sideeffects */
	null = (CamelStream *)camel_stream_null_new ();
	filter = camel_stream_filter_new_with_stream (null);
	
	/* if we're looking for the best charset, then we need to convert to UTF-8 */
	if (istext && (required & CAMEL_BESTENC_GET_CHARSET) != 0
	    && (charsetin = camel_content_type_param (content->mime_type, "charset"))) {
		charenc = camel_mime_filter_charset_new_convert (charsetin, "UTF-8");
		if (charenc != NULL)
			idc = camel_stream_filter_add (filter, (CamelMimeFilter *)charenc);
		charsetin = NULL;
	}
	
	bestenc = camel_mime_filter_bestenc_new (flags);
	idb = camel_stream_filter_add (filter, (CamelMimeFilter *)bestenc);
	d(printf("writing to checking stream\n"));
	camel_data_wrapper_decode_to_stream (content, (CamelStream *)filter);
	camel_stream_filter_remove (filter, idb);
	if (idc != -1) {
		camel_stream_filter_remove (filter, idc);
		camel_object_unref (charenc);
		charenc = NULL;
	}
	
	if (istext && (required & CAMEL_BESTENC_GET_CHARSET) != 0) {
		charsetin = camel_mime_filter_bestenc_get_best_charset (bestenc);
		d(printf("best charset = %s\n", charsetin ? charsetin : "(null)"));
		charset = g_strdup (charsetin);
		
		charsetin = camel_content_type_param (content->mime_type, "charset");
	} else {
		charset = NULL;
	}
	
	/* if we have US-ASCII, or we're not doing text, we dont need to bother with the rest */
	if (istext && charsetin && charset && (required & CAMEL_BESTENC_GET_CHARSET) != 0) {
		d(printf("have charset, trying conversion/etc\n"));
		
		/* now that 'bestenc' has told us what the best encoding is, we can use that to create
		   a charset conversion filter as well, and then re-add the bestenc to filter the
		   result to find the best encoding to use as well */
		
		charenc = camel_mime_filter_charset_new_convert (charsetin, charset);
		if (charenc != NULL) {
			/* otherwise, try another pass, converting to the real charset */
			
			camel_mime_filter_reset ((CamelMimeFilter *)bestenc);
			camel_mime_filter_bestenc_set_flags (bestenc, CAMEL_BESTENC_GET_ENCODING |
							     CAMEL_BESTENC_LF_IS_CRLF | callerflags);
			
			camel_stream_filter_add (filter, (CamelMimeFilter *)charenc);
			camel_stream_filter_add (filter, (CamelMimeFilter *)bestenc);
			
			/* and write it to the new stream */
			camel_data_wrapper_write_to_stream (content, (CamelStream *)filter);
			
			camel_object_unref (charenc);
		}
	}
	
	encoding = camel_mime_filter_bestenc_get_best_encoding (bestenc, enctype);
	
	camel_object_unref (filter);
	camel_object_unref (bestenc);
	camel_object_unref (null);
	
	d(printf("done, best encoding = %d\n", encoding));
	
	if (charsetp)
		*charsetp = charset;
	else
		g_free (charset);
	
	return encoding;
}

struct _enc_data {
	CamelBestencRequired required;
	CamelBestencEncoding enctype;
};

static gboolean
best_encoding (CamelMimeMessage *msg, CamelMimePart *part, void *datap)
{
	struct _enc_data *data = datap;
	CamelTransferEncoding encoding;
	CamelDataWrapper *wrapper;
	char *charset;
	
	wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (part));
	if (!wrapper)
		return FALSE;
	
	/* we only care about actual content objects */
	if (!CAMEL_IS_MULTIPART (wrapper) && !CAMEL_IS_MIME_MESSAGE (wrapper)) {
		encoding = find_best_encoding (part, data->required, data->enctype, &charset);
		/* we always set the encoding, if we got this far.  GET_CHARSET implies
		   also GET_ENCODING */
		camel_mime_part_set_encoding (part, encoding);
		
		if ((data->required & CAMEL_BESTENC_GET_CHARSET) != 0) {
			if (camel_content_type_is (((CamelDataWrapper *) part)->mime_type, "text", "*")) {
				char *newct;
				
				/* FIXME: ick, the part content_type interface needs fixing bigtime */
				camel_content_type_set_param (((CamelDataWrapper *) part)->mime_type, "charset",
							       charset ? charset : "us-ascii");
				newct = camel_content_type_format (((CamelDataWrapper *) part)->mime_type);
				if (newct) {
					d(printf("Setting content-type to %s\n", newct));
					
					camel_mime_part_set_content_type (part, newct);
					g_free (newct);
				}
			}
		}
		
		g_free (charset);
	}
	
	return TRUE;
}

void
camel_mime_message_set_best_encoding (CamelMimeMessage *msg, CamelBestencRequired required, CamelBestencEncoding enctype)
{
	struct _enc_data data;
	
	if ((required & (CAMEL_BESTENC_GET_ENCODING|CAMEL_BESTENC_GET_CHARSET)) == 0)
		return;
	
	data.required = required;
	data.enctype = enctype;
	
	camel_mime_message_foreach_part (msg, best_encoding, &data);
}

void
camel_mime_message_encode_8bit_parts (CamelMimeMessage *mime_message)
{
	camel_mime_message_set_best_encoding (mime_message, CAMEL_BESTENC_GET_ENCODING, CAMEL_BESTENC_7BIT);
}


struct _check_content_id {
	CamelMimePart *part;
	const char *content_id;
};

static gboolean
check_content_id (CamelMimeMessage *message, CamelMimePart *part, void *data)
{
	struct _check_content_id *check = (struct _check_content_id *) data;
	const char *content_id;
	gboolean found;
	
	content_id = camel_mime_part_get_content_id (part);
	
	found = content_id && !strcmp (content_id, check->content_id) ? TRUE : FALSE;
	if (found) {
		check->part = part;
		camel_object_ref (CAMEL_OBJECT (part));
	}
	
	return !found;
}

CamelMimePart *
camel_mime_message_get_part_by_content_id (CamelMimeMessage *message, const char *id)
{
	struct _check_content_id check;
	
	g_return_val_if_fail (CAMEL_IS_MIME_MESSAGE (message), NULL);
	
	if (id == NULL)
		return NULL;
	
	check.content_id = id;
	check.part = NULL;
	
	camel_mime_message_foreach_part (message, check_content_id, &check);
	
	return check.part;
}

static char *tz_months[] = {
	"Jan", "Feb", "Mar", "Apr", "May", "Jun",
	"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};

static char *tz_days[] = {
	"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};

char *
camel_mime_message_build_mbox_from (CamelMimeMessage *message)
{
	struct _camel_header_raw *header = ((CamelMimePart *)message)->headers;
	GString *out = g_string_new("From ");
	char *ret;
	const char *tmp;
	time_t thetime;
	int offset;
	struct tm tm;
	
	tmp = camel_header_raw_find (&header, "Sender", NULL);
	if (tmp == NULL)
		tmp = camel_header_raw_find (&header, "From", NULL);
	if (tmp != NULL) {
		struct _camel_header_address *addr = camel_header_address_decode (tmp, NULL);
		
		tmp = NULL;
		if (addr) {
			if (addr->type == HEADER_ADDRESS_NAME) {
				g_string_append (out, addr->v.addr);
				tmp = "";
			}
			camel_header_address_unref (addr);
		}
	}
	
	if (tmp == NULL)
		g_string_append (out, "unknown@nodomain.now.au");
	
	/* try use the received header to get the date */
	tmp = camel_header_raw_find (&header, "Received", NULL);
	if (tmp) {
		tmp = strrchr(tmp, ';');
		if (tmp)
			tmp++;
	}
	
	/* if there isn't one, try the Date field */
	if (tmp == NULL)
		tmp = camel_header_raw_find (&header, "Date", NULL);
	
	thetime = camel_header_decode_date (tmp, &offset);
	thetime += ((offset / 100) * (60 * 60)) + (offset % 100) * 60;
	gmtime_r (&thetime, &tm);
	g_string_append_printf (out, " %s %s %2d %02d:%02d:%02d %4d\n",
				tz_days[tm.tm_wday], tz_months[tm.tm_mon],
				tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec,
				tm.tm_year + 1900);
	
	ret = out->str;
	g_string_free (out, FALSE);
	
	return ret;
}