path: root/em-format/e-mail-parser-text-plain.c

/*
 * e-mail-parser-text-plain.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 */

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

#include "e-mail-format-extensions.h"

#include <em-format/e-mail-parser-extension.h>
#include <em-format/e-mail-parser.h>
#include <em-format/e-mail-inline-filter.h>
#include <em-format/e-mail-part-utils.h>
#include <e-util/e-util.h>

#include <glib/gi18n-lib.h>
#include <camel/camel.h>
#include <ctype.h>

typedef struct _EMailParserTextPlain {
    GObject parent;
} EMailParserTextPlain;

typedef struct _EMailParserTextPlainClass {
    GObjectClass parent_class;
} EMailParserTextPlainClass;

static void e_mail_parser_parser_extension_interface_init (EMailParserExtensionInterface *iface);
static void e_mail_parser_mail_extension_interface_init (EMailExtensionInterface *iface);

G_DEFINE_TYPE_EXTENDED (
    EMailParserTextPlain,
    e_mail_parser_text_plain,
    G_TYPE_OBJECT,
    0,
    G_IMPLEMENT_INTERFACE (
        E_TYPE_MAIL_EXTENSION,
        e_mail_parser_mail_extension_interface_init)
    G_IMPLEMENT_INTERFACE (
        E_TYPE_MAIL_PARSER_EXTENSION,
        e_mail_parser_parser_extension_interface_init));

static const gchar *parser_mime_types[] = { "text/plain", "text/*", NULL };

static gboolean
part_is_empty (CamelMimePart *part)
{
    CamelDataWrapper *dw;
    GByteArray *ba;
    guint i;

    dw = camel_medium_get_content (CAMEL_MEDIUM (part));
    ba = camel_data_wrapper_get_byte_array (dw);

    if (!ba)
        return TRUE;

    for (i = 0; i < ba->len; i++) {

        /* Checks for \n, \t, \f, \r, \v and space */
        if (!isspace (ba->data[i]))
            return FALSE;
    }

    return TRUE;
}

static GSList *
process_part (EMailParser *parser,
              GString *part_id,
              gint part_number,
              CamelMimePart *part,
              gboolean is_attachment,
              GCancellable *cancellable)
{
    CamelContentType *type;
    EMailPart *empart;
    gint s_len = part_id->len;
    GSList *parts;

    if (part_is_empty (part)) {
        return g_slist_alloc ();
    }

    type = camel_mime_part_get_content_type (part);
    if (!camel_content_type_is (type, "text", "*")) {

        parts = e_mail_parser_parse_part (
                parser, CAMEL_MIME_PART (part),
                part_id, cancellable);
        return parts;

    } else if (!camel_content_type_is (type, "text", "calendar")) {

        g_string_append_printf (part_id, ".plain_text.%d", part_number);

        empart = e_mail_part_new (part, part_id->str);
        empart->mime_type = camel_content_type_simple (type);

        g_string_truncate (part_id, s_len);

        if (is_attachment) {

            return e_mail_parser_wrap_as_attachment (
                    parser, part,
                    g_slist_append (NULL, empart),
                    part_id, cancellable);

        }

        return g_slist_append (NULL, empart);
    }

    g_string_append_printf (part_id, ".inline.%d", part_number);

    parts = e_mail_parser_parse_part (
            parser, CAMEL_MIME_PART (part),
            part_id, cancellable);

    g_string_truncate (part_id, s_len);

    return parts;
}

static GSList *
empe_text_plain_parse (EMailParserExtension *extension,
                       EMailParser *parser,
                       CamelMimePart *part,
                       GString *part_id,
                       GCancellable *cancellable)
{
    GSList *parts;
    CamelStream *filtered_stream, *null;
    CamelMultipart *mp;
    CamelDataWrapper *dw;
    CamelContentType *type;
    gint i, count;
    EMailInlineFilter *inline_filter;
    gboolean charset_added = FALSE;
    const gchar *snoop_type = NULL;
    gboolean is_attachment;

    if (g_cancellable_is_cancelled (cancellable))
        return NULL;

    dw = camel_medium_get_content ((CamelMedium *) part);
    if (!dw)
        return NULL;

    /* This scans the text part for inline-encoded data, creates
     * a multipart of all the parts inside it. */

    /* FIXME: We should discard this multipart if it only contains
     * the original text, but it makes this hash lookup more complex */
    if (!dw->mime_type)
        snoop_type = e_mail_part_snoop_type (part);

    /* if we had to snoop the part type to get here, then
     * use that as the base type, yuck */
    if (snoop_type == NULL
        || (type = camel_content_type_decode (snoop_type)) == NULL) {
        type = dw->mime_type;
        camel_content_type_ref (type);
    }

    if (dw->mime_type && type != dw->mime_type && camel_content_type_param (dw->mime_type, "charset")) {
        camel_content_type_set_param (type, "charset", camel_content_type_param (dw->mime_type, "charset"));
        charset_added = TRUE;
    }

    null = camel_stream_null_new ();
    filtered_stream = camel_stream_filter_new (null);
    g_object_unref (null);
    inline_filter = e_mail_inline_filter_new (
        camel_mime_part_get_encoding (part),
        type,
        camel_mime_part_get_filename (part));

    camel_stream_filter_add (
        CAMEL_STREAM_FILTER (filtered_stream),
        CAMEL_MIME_FILTER (inline_filter));
    camel_data_wrapper_decode_to_stream_sync (
        dw, (CamelStream *) filtered_stream, cancellable, NULL);
    camel_stream_close ((CamelStream *) filtered_stream, cancellable, NULL);
    g_object_unref (filtered_stream);

    if (!e_mail_inline_filter_found_any (inline_filter)) {
        g_object_unref (inline_filter);
        camel_content_type_unref (type);

        return process_part (
            parser, part_id, 0,
            part, e_mail_part_is_attachment (part),
            cancellable);
    }

    mp = e_mail_inline_filter_get_multipart (inline_filter);

    if (charset_added) {
        camel_content_type_set_param (type, "charset", NULL);
    }

    g_object_unref (inline_filter);
    camel_content_type_unref (type);

    /* We handle our made-up multipart here, so we don't recursively call ourselves */
    count = camel_multipart_get_number (mp);
    parts = NULL;

    is_attachment = ((count == 1) && (e_mail_part_is_attachment (part)));

    for (i = 0; i < count; i++) {
        CamelMimePart *newpart = camel_multipart_get_part (mp, i);

        if (!newpart)
            continue;

        parts = g_slist_concat (
            parts,
            process_part (
                parser, part_id, i,
                newpart, is_attachment,
                cancellable));
    }

    g_object_unref (mp);

    return parts;
}

static const gchar **
empe_text_plain_mime_types (EMailExtension *extension)
{
    return parser_mime_types;
}

static void
e_mail_parser_text_plain_class_init (EMailParserTextPlainClass *class)
{
}

static void
e_mail_parser_parser_extension_interface_init (EMailParserExtensionInterface *iface)
{
    iface->parse = empe_text_plain_parse;
}

static void
e_mail_parser_mail_extension_interface_init (EMailExtensionInterface *iface)
{
    iface->mime_types = empe_text_plain_mime_types;
}

static void
e_mail_parser_text_plain_init (EMailParserTextPlain *parser)
{

}