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/* -*- 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@helixcode.com>
 *          Jeffrey Stedfast <fejj@helixcode.com>
 *
 * Copyright 1999, 2000 Helix Code, Inc. (http://www.helixcode.com)
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#include <config.h>

#include "camel-mime-message.h"
#include "camel-multipart.h"
#include "gmime-content-field.h"
#include "camel-stream-mem.h"
#include "string-utils.h"
#include "hash-table-utils.h"
#include <stdio.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_CC,
    HEADER_BCC,
    HEADER_DATE
} CamelHeaderType;

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

static GHashTable *header_name_table;

static CamelMimePartClass *parent_class=NULL;

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

static int write_to_stream (CamelDataWrapper *data_wrapper, CamelStream *stream);
static void add_header (CamelMedium *medium, const char *header_name, const void *header_value);
static void set_header (CamelMedium *medium, const char *header_name, const void *header_value);
static void remove_header (CamelMedium *medium, const char *header_name);
static int construct_from_parser (CamelMimePart *, CamelMimeParser *);
static void g_lib_is_uber_crappy_shit(gpointer whocares, gpointer getlost, gpointer blah);

/* 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 (g_strcase_hash, g_strcase_equal);
    for (i=0;header_names[i];i++)
        g_hash_table_insert (header_name_table, header_names[i], (gpointer)i+1);

    /* virtual method overload */
    camel_data_wrapper_class->write_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;
    
    camel_data_wrapper_set_mime_type (CAMEL_DATA_WRAPPER (object), "message/rfc822");

    mime_message->recipients =  g_hash_table_new(g_strcase_hash, g_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_str = NULL;
}

static void           
camel_mime_message_finalize (CamelObject *object)
{
    CamelMimeMessage *message = CAMEL_MIME_MESSAGE (object);
    
    g_free (message->date_str);
    g_free (message->subject);
    g_free (message->reply_to);
    g_free (message->from);

    g_hash_table_foreach (message->recipients, g_lib_is_uber_crappy_shit, 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;
}

/* annoying way to free objects in a hashtable, i mean, its not like anyone
   would want to store them in a hashtable, really */
/* peterw: somebody's not bitter :-) */
static void g_lib_is_uber_crappy_shit(gpointer whocares, gpointer getlost, gpointer blah)
{
    camel_object_unref((CamelObject *)getlost);
}



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)
{
    g_assert(message);
    if (date == CAMEL_MESSAGE_DATE_CURRENT) {
        struct tm *local;
        int tz;

        date = time(0);
        local = localtime(&date);
        offset = 0;
#if defined(HAVE_TIMEZONE)
        tz = timezone;
#elif defined(HAVE_TM_GMTOFF)
        tz = local->tm_gmtoff;
#endif
        offset = ((tz/60/60) * 100) + (tz/60 % 60);
    }
    message->date = date;
    message->date_offset = offset;
    g_free(message->date_str);
    message->date_str = header_format_date(date, offset);

    CAMEL_MEDIUM_CLASS(parent_class)->set_header((CamelMedium *)message, "Date", message->date_str);
}

void
camel_mime_message_get_date(CamelMimeMessage *message,  time_t *date, int *offset)
{
    if (message->date == CAMEL_MESSAGE_DATE_CURRENT)
        camel_mime_message_set_date(message, CAMEL_MESSAGE_DATE_CURRENT, 0);
    if (date)
        *date = message->date;
    if (offset)
        *offset = message->date_offset;
}

char *
camel_mime_message_get_date_string (CamelMimeMessage *message)
{
    if (message->date == CAMEL_MESSAGE_DATE_CURRENT)
        camel_mime_message_set_date (message, CAMEL_MESSAGE_DATE_CURRENT, 0);
    return message->date_str;
}

const gchar *
camel_mime_message_get_received_date (CamelMimeMessage *message)
{
    /* FIXME: is this the received date? and if so then get_sent_date must be wrong */
    if (message->date == CAMEL_MESSAGE_DATE_CURRENT)
        camel_mime_message_set_date (message, CAMEL_MESSAGE_DATE_CURRENT, 0);
    return message->date_str;
}

const gchar *
camel_mime_message_get_sent_date (CamelMimeMessage *message)
{
    /* FIXME: is this the sent date? and if so then get_received_date must be wrong */
    if (message->date == CAMEL_MESSAGE_DATE_CURRENT)
        camel_mime_message_set_date (message, CAMEL_MESSAGE_DATE_CURRENT, 0);
    return message->date_str;
}

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

void
camel_mime_message_set_reply_to (CamelMimeMessage *mime_message, const gchar *reply_to)
{
    g_assert (mime_message);

    /* FIXME: check format of string, handle it nicer ... */

    g_free(mime_message->reply_to);
    mime_message->reply_to = g_strdup(reply_to);
    CAMEL_MEDIUM_CLASS(parent_class)->set_header((CamelMedium *)mime_message, "Reply-To", reply_to);
}

const gchar *
camel_mime_message_get_reply_to (CamelMimeMessage *mime_message)
{
    g_assert (mime_message);

    return mime_message->reply_to;
}

void
camel_mime_message_set_subject (CamelMimeMessage *mime_message,
                const gchar *subject)
{
    char *text;
    g_assert (mime_message);

    g_free(mime_message->subject);
    mime_message->subject = g_strstrip (g_strdup (subject));
    text = header_encode_string(subject);
    CAMEL_MEDIUM_CLASS(parent_class)->set_header((CamelMedium *)mime_message, "Subject", text);
    g_free(text);
}

const gchar *
camel_mime_message_get_subject (CamelMimeMessage *mime_message)
{
    g_assert (mime_message);

    return mime_message->subject;
}

/* *** From: */
void
camel_mime_message_set_from (CamelMimeMessage *mime_message, const gchar *from)
{
    g_assert (mime_message);

    g_free(mime_message->from);
    mime_message->from = g_strdup(from);
    CAMEL_MEDIUM_CLASS(parent_class)->set_header((CamelMedium *)mime_message, "From", from);
}

const gchar *
camel_mime_message_get_from (CamelMimeMessage *mime_message)
{
    g_assert (mime_message);

    return mime_message->from;
}

/*  ****  */

void
camel_mime_message_add_recipient (CamelMimeMessage *mime_message, 
                  const gchar *type, 
                  const gchar *name, const char *address)
{
    CamelInternetAddress *addr;
    char *text;

    g_assert (mime_message);

    addr = g_hash_table_lookup(mime_message->recipients, type);
    if (addr == NULL) {
        g_warning("trying to add a non-valid receipient type: %s = %s %s", type, name, address);
        return;
    }

    camel_internet_address_add(addr, name, address);

    /* FIXME: maybe this should be delayed till we're ready to write out? */
    text = camel_address_encode((CamelAddress*)addr);
    CAMEL_MEDIUM_CLASS(parent_class)->set_header((CamelMedium *)mime_message, type, text);
    g_free(text);
}

void
camel_mime_message_remove_recipient_address (CamelMimeMessage *mime_message,
                         const gchar *type,
                         const gchar *address)
{
    CamelInternetAddress *addr;
    int index;
    char *text;


    g_assert (mime_message);

    addr = g_hash_table_lookup(mime_message->recipients, type);
    if (addr == NULL) {
        g_warning("trying to remove a non-valid receipient type: %s = %s", type, address);
        return;
    }
    index = camel_internet_address_find_address(addr, address, NULL);
    if (index == -1) {
        g_warning("trying to remove address for nonexistand address: %s", address);
        return;
    }

    camel_address_remove((CamelAddress *)addr, index);

    /* FIXME: maybe this should be delayed till we're ready to write out? */
    text = camel_address_encode((CamelAddress *)addr);
    CAMEL_MEDIUM_CLASS(parent_class)->set_header((CamelMedium *)mime_message, type, text);
    g_free(text);
}

void
camel_mime_message_remove_recipient_name (CamelMimeMessage *mime_message,
                      const gchar *type,
                      const gchar *name)
{
    CamelInternetAddress *addr;
    int index;
    char *text;

    g_assert (mime_message);

    addr = g_hash_table_lookup(mime_message->recipients, type);
    if (addr == NULL) {
        g_warning("trying to remove a non-valid receipient type: %s = %s", type, name);
        return;
    }
    index = camel_internet_address_find_name(addr, name, NULL);
    if (index == -1) {
        g_warning("trying to remove address for nonexistand name: %s", name);
        return;
    }

    camel_address_remove((CamelAddress *)addr, index);

    /* FIXME: maybe this should be delayed till we're ready to write out? */
    text = camel_address_encode((CamelAddress *)addr);
    CAMEL_MEDIUM_CLASS(parent_class)->set_header((CamelMedium *)mime_message, type, text);
    g_free(text);
}

const CamelInternetAddress *
camel_mime_message_get_recipients (CamelMimeMessage *mime_message, 
                   const gchar *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;
    int len;
    int state;
    int ret;

    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 HSCAN_EOF: case HSCAN_FROM_END: /* these doesn't belong to us */
        camel_mime_parser_unstep(mp);
    case HSCAN_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"));
#ifndef NO_WARNINGS
#warning "return a real error code"
#endif
    return 0;
}

static int
write_to_stream (CamelDataWrapper *data_wrapper, CamelStream *stream)
{
    CamelMimeMessage *mm = CAMEL_MIME_MESSAGE (data_wrapper);

    /* force mandatory headers ... */
    if (mm->from == NULL) {
        g_warning("No from set for message");
        camel_mime_message_set_from(mm, "");
    }
    if (mm->date_str == NULL) {
        g_warning("Application did not set date, using 'now'");
        camel_mime_message_set_date(mm, CAMEL_MESSAGE_DATE_CURRENT, 0);
    }
    if (mm->subject == NULL) {
        g_warning("Application did not set subject, creating one");
        camel_mime_message_set_subject(mm, "No Subject");
    }

    /* 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);
}

static char *
format_address(const char *text)
{
    struct _header_address *addr;
    char *ret;

    addr = header_address_decode(text);
    if (addr) {
        ret = header_address_list_format(addr);
        header_address_list_clear(&addr);
    } else {
        ret = g_strdup(text);
    }
    return ret;
}

/* FIXME: check format of fields. */
static gboolean
process_header(CamelMedium *medium, const char *header_name, const char *header_value)
{
    CamelHeaderType header_type;
    CamelMimeMessage *message = CAMEL_MIME_MESSAGE (medium);
    CamelInternetAddress *addr;

    header_type = (CamelHeaderType) g_hash_table_lookup (header_name_table, header_name);
    switch (header_type) {
    case HEADER_FROM:
        g_free(message->from);
        message->from = format_address(header_value);
        break;
    case HEADER_REPLY_TO:
        g_free(message->reply_to);
        message->reply_to = format_address(header_value);
        break;
    case HEADER_SUBJECT:
        g_free(message->subject);
        message->subject = g_strstrip (header_decode_string(header_value));
        break;
    case HEADER_TO:
    case HEADER_CC:
    case HEADER_BCC:
        addr = g_hash_table_lookup(message->recipients, header_name);
        if (header_value)
            camel_address_decode((CamelAddress *)addr, header_value);
        else
            camel_address_remove((CamelAddress *)addr, -1);
        break;
    case HEADER_DATE:
        g_free(message->date_str);
        message->date_str = g_strdup(header_value);
        if (header_value) {
            message->date = header_decode_date(header_value, &message->date_offset);
        } else {
            message->date = CAMEL_MESSAGE_DATE_CURRENT;
        }
        break;
    default:
        return FALSE;
    }
    return TRUE;
}

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

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

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

static gboolean
multipart_has_8bit_parts (CamelMultipart *multipart)
{
    gboolean has_8bit = FALSE;
    int i, nparts;
    
    nparts = camel_multipart_get_number (multipart);
    
    for (i = 0; i < nparts && !has_8bit; i++) {
        GMimeContentField *content;
        CamelMimePart *mime_part;
        
        mime_part = camel_multipart_get_part (multipart, i);
        content = camel_mime_part_get_content_type (mime_part);
        
        if (gmime_content_field_is_type (content, "multipart", "*")) {
            CamelDataWrapper *wrapper;
            CamelMultipart *mpart;
            
            wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part));
            mpart = CAMEL_MULTIPART (wrapper);
            
            has_8bit = multipart_has_8bit_parts (mpart);
        } else {
            /* see if this part is 8bit */
            has_8bit = camel_mime_part_get_encoding (mime_part) == CAMEL_MIME_PART_ENCODING_8BIT;
        }
    }
    
    return has_8bit;
}

gboolean
camel_mime_message_has_8bit_parts (CamelMimeMessage *mime_message)
{
    GMimeContentField *content;
    gboolean has_8bit = FALSE;
    
    content = camel_mime_part_get_content_type (CAMEL_MIME_PART (mime_message));
    
    if (gmime_content_field_is_type (content, "multipart", "*")) {
        CamelDataWrapper *wrapper;
        CamelMultipart *multipart;
        
        wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (CAMEL_MIME_PART (mime_message)));
        multipart = CAMEL_MULTIPART (wrapper);
        
        has_8bit = multipart_has_8bit_parts (multipart);
    } else {
        /* single-part message so just check this part */
        has_8bit = camel_mime_part_get_encoding (CAMEL_MIME_PART (mime_message)) == CAMEL_MIME_PART_ENCODING_8BIT;
    }
    
    return has_8bit;
}

static int
best_encoding (const guchar *text)
{
    guchar *ch;
    int count = 0;
    int total;
    
    for (ch = (guchar *) text; *ch; ch++)
        if (*ch > (guchar) 127)
            count++;
    
    total = (int) (ch - text);
    
    if ((float) count <= total * 0.17)
        return CAMEL_MIME_PART_ENCODING_QUOTEDPRINTABLE;
    else
        return CAMEL_MIME_PART_ENCODING_BASE64;
}

static void
multipart_encode_8bit_parts (CamelMultipart *multipart)
{
    int i, nparts;
    
    nparts = camel_multipart_get_number (multipart);
    
    for (i = 0; i < nparts; i++) {
        GMimeContentField *content;
        CamelMimePart *mime_part;
        
        mime_part = camel_multipart_get_part (multipart, i);
        content = camel_mime_part_get_content_type (mime_part);
        
        if (gmime_content_field_is_type (content, "multipart", "*")) {
            /* ...and the search for Spock continues */
            CamelDataWrapper *wrapper;
            CamelMultipart *mpart;
            
            wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part));
            mpart = CAMEL_MULTIPART (wrapper);
            
            multipart_encode_8bit_parts (mpart);
        } else {
            /* re-encode this if necessary */
            gboolean is_8bit;
            
            is_8bit = camel_mime_part_get_encoding (mime_part) == CAMEL_MIME_PART_ENCODING_8BIT;
            if (is_8bit) {
                CamelStream *stream;
                GByteArray *array;
                guchar *content;
                
                array = g_byte_array_new ();
                stream = camel_stream_mem_new_with_byte_array (array);
                camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (mime_part), stream);
                g_byte_array_append (array, "", 1);
                
                content = array->data;
                g_byte_array_free (array, FALSE);
                
                camel_mime_part_set_encoding (mime_part, best_encoding (content));
                g_free (content);
                camel_object_unref (CAMEL_OBJECT (stream));
            }
        }
    }
}

void
camel_mime_message_encode_8bit_parts (CamelMimeMessage *mime_message)
{
    GMimeContentField *content;
    
    content = camel_mime_part_get_content_type (CAMEL_MIME_PART (mime_message));
    
    if (gmime_content_field_is_type (content, "multipart", "*")) {
        /* search for Spock */
        CamelDataWrapper *wrapper;
        CamelMultipart *multipart;
        
        wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (CAMEL_MIME_PART (mime_message)));
        multipart = CAMEL_MULTIPART (wrapper);
        
        multipart_encode_8bit_parts (multipart);
    } else {
        /* re-encode if we need to */
        gboolean is_8bit;
        
        is_8bit = camel_mime_part_get_encoding (CAMEL_MIME_PART (mime_message)) == CAMEL_MIME_PART_ENCODING_8BIT;
        if (is_8bit) {
            /* FIXME: is there a better way of doing this? */
            CamelStream *stream;
            GByteArray *array;
            guchar *content;
            
            array = g_byte_array_new ();
            stream = camel_stream_mem_new_with_byte_array (array);
            camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (CAMEL_MIME_PART (mime_message)), stream);
            g_byte_array_append (array, "", 1);
            
            content = array->data;
            g_byte_array_free (array, FALSE);
                        
            camel_mime_part_set_encoding (CAMEL_MIME_PART (mime_message), best_encoding (content));
            g_free (content);
            camel_object_unref (CAMEL_OBJECT (stream));
        }
    }
}