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path: root/libemail-engine/e-mail-utils.c
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/*
 * 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/>
 *
 *
 * Authors:
 *      Srinivasa Ragavan <sragavan@gnome.org>
 *
 *
 */

#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <time.h>

#include <glib/gstdio.h>

#ifdef G_OS_WIN32
/* Work around namespace clobbage in <windows.h> */
#define DATADIR windows_DATADIR
#include <windows.h>
#undef DATADIR
#undef interface
#endif

#include <libebook/e-book-client.h>
#include <libebook/e-book-query.h>

#include <glib/gi18n.h>

#include <gio/gio.h>

#include <libedataserver/e-data-server-util.h>
#include <libedataserver/e-flag.h>
#include <libedataserver/e-proxy.h>

#include "libemail-utils/e-account-utils.h"
#include "libemail-utils/mail-mt.h"

#include "e-mail-folder-utils.h"
#include "e-mail-session.h"
#include "e-mail-utils.h"
#include "mail-tools.h"

#define d(x)

/**
 * em_utils_folder_is_templates:
 * @folder: a #CamelFolder
 *
 * Decides if @folder is a Templates folder.
 *
 * Returns %TRUE if this is a Templates folder or %FALSE otherwise.
 **/

gboolean
em_utils_folder_is_templates (CamelFolder *folder)
{
    CamelFolder *local_templates_folder;
    CamelSession *session;
    CamelStore *store;
    EAccountList *account_list;
    EIterator *iterator;
    gchar *folder_uri;
    gboolean is_templates = FALSE;

    g_return_val_if_fail (CAMEL_IS_FOLDER (folder), FALSE);

    store = camel_folder_get_parent_store (folder);
    session = camel_service_get_session (CAMEL_SERVICE (store));

    local_templates_folder =
        e_mail_session_get_local_folder (
        E_MAIL_SESSION (session), E_MAIL_LOCAL_FOLDER_TEMPLATES);

    if (folder == local_templates_folder)
        return TRUE;

    folder_uri = e_mail_folder_uri_from_folder (folder);

    account_list = e_get_account_list ();
    iterator = e_list_get_iterator (E_LIST (account_list));

    while (!is_templates && e_iterator_is_valid (iterator)) {
        EAccount *account;

        /* XXX EIterator misuses const. */
        account = (EAccount *) e_iterator_get (iterator);

        if (account->templates_folder_uri != NULL)
            is_templates = e_mail_folder_uri_equal (
                session, folder_uri,
                account->templates_folder_uri);

        e_iterator_next (iterator);
    }

    g_object_unref (iterator);
    g_free (folder_uri);

    return is_templates;
}

/**
 * em_utils_folder_is_drafts:
 * @folder: a #CamelFolder
 *
 * Decides if @folder is a Drafts folder.
 *
 * Returns %TRUE if this is a Drafts folder or %FALSE otherwise.
 **/
gboolean
em_utils_folder_is_drafts (CamelFolder *folder)
{
    CamelFolder *local_drafts_folder;
    CamelSession *session;
    CamelStore *store;
    MailFolderCache *cache;
    EMailSession *mail_session;
    CamelFolderInfoFlags flags = 0;
    EAccountList *account_list;
    EIterator *iterator;
    gchar *folder_uri;
    gboolean is_drafts = FALSE;

    g_return_val_if_fail (CAMEL_IS_FOLDER (folder), FALSE);

    store = camel_folder_get_parent_store (folder);
    session = camel_service_get_session (CAMEL_SERVICE (store));
    mail_session = E_MAIL_SESSION (session);

    local_drafts_folder =
        e_mail_session_get_local_folder (
        mail_session, E_MAIL_LOCAL_FOLDER_DRAFTS);

    if (folder == local_drafts_folder)
        return TRUE;

    cache = e_mail_session_get_folder_cache (mail_session);

    /* user can select Inbox as his Draft folder - in that case prefer Inbox type */
    if (mail_folder_cache_get_folder_info_flags (cache, folder, &flags) &&
        (flags & CAMEL_FOLDER_TYPE_MASK) == CAMEL_FOLDER_TYPE_INBOX)
        return FALSE;

    folder_uri = e_mail_folder_uri_from_folder (folder);

    account_list = e_get_account_list ();
    iterator = e_list_get_iterator (E_LIST (account_list));

    while (!is_drafts && e_iterator_is_valid (iterator)) {
        EAccount *account;

        /* XXX EIterator misuses const. */
        account = (EAccount *) e_iterator_get (iterator);

        if (account->drafts_folder_uri != NULL)
            is_drafts = e_mail_folder_uri_equal (
                session, folder_uri,
                account->drafts_folder_uri);

        e_iterator_next (iterator);
    }

    g_object_unref (iterator);
    g_free (folder_uri);

    return is_drafts;
}

/**
 * em_utils_folder_is_sent:
 * @folder: a #CamelFolder
 *
 * Decides if @folder is a Sent folder.
 *
 * Returns %TRUE if this is a Sent folder or %FALSE otherwise.
 **/
gboolean
em_utils_folder_is_sent (CamelFolder *folder)
{
    CamelFolder *local_sent_folder;
    CamelSession *session;
    CamelStore *store;
    MailFolderCache *cache;
    EMailSession *mail_session;
    CamelFolderInfoFlags flags = 0;
    EAccountList *account_list;
    EIterator *iterator;
    gchar *folder_uri;
    gboolean is_sent = FALSE;

    g_return_val_if_fail (CAMEL_IS_FOLDER (folder), FALSE);

    store = camel_folder_get_parent_store (folder);
    session = camel_service_get_session (CAMEL_SERVICE (store));
    mail_session = E_MAIL_SESSION (session);

    local_sent_folder =
        e_mail_session_get_local_folder (
        mail_session, E_MAIL_LOCAL_FOLDER_SENT);

    if (folder == local_sent_folder)
        return TRUE;

    cache = e_mail_session_get_folder_cache (mail_session);

    /* user can select Inbox as his Sent folder - in that case prefer Inbox type */
    if (mail_folder_cache_get_folder_info_flags (cache, folder, &flags) &&
        (flags & CAMEL_FOLDER_TYPE_MASK) == CAMEL_FOLDER_TYPE_INBOX)
        return FALSE;

    folder_uri = e_mail_folder_uri_from_folder (folder);

    account_list = e_get_account_list ();
    iterator = e_list_get_iterator (E_LIST (account_list));

    while (!is_sent && e_iterator_is_valid (iterator)) {
        EAccount *account;

        /* XXX EIterator misuses const. */
        account = (EAccount *) e_iterator_get (iterator);

        if (account->sent_folder_uri != NULL)
            is_sent = e_mail_folder_uri_equal (
                session, folder_uri,
                account->sent_folder_uri);

        e_iterator_next (iterator);
    }

    g_object_unref (iterator);
    g_free (folder_uri);

    return is_sent;
}

/**
 * em_utils_folder_is_outbox:
 * @folder: a #CamelFolder
 *
 * Decides if @folder is an Outbox folder.
 *
 * Returns %TRUE if this is an Outbox folder or %FALSE otherwise.
 **/
gboolean
em_utils_folder_is_outbox (CamelFolder *folder)
{
    CamelStore *store;
    CamelSession *session;
    CamelFolder *local_outbox_folder;

    g_return_val_if_fail (CAMEL_IS_FOLDER (folder), FALSE);

    store = camel_folder_get_parent_store (folder);
    session = camel_service_get_session (CAMEL_SERVICE (store));

    local_outbox_folder =
        e_mail_session_get_local_folder (
        E_MAIL_SESSION (session), E_MAIL_LOCAL_FOLDER_OUTBOX);

    return (folder == local_outbox_folder);
}

/* ********************************************************************** */

/* runs sync, in main thread */
static gpointer
emu_addr_setup (gpointer user_data)
{
    GError *err = NULL;
    ESourceList **psource_list = user_data;

    if (!e_book_client_get_sources (psource_list, &err))
        g_error_free (err);

    return NULL;
}

static void
emu_addr_cancel_stop (gpointer data)
{
    gboolean *stop = data;

    g_return_if_fail (stop != NULL);

    *stop = TRUE;
}

static void
emu_addr_cancel_cancellable (gpointer data)
{
    GCancellable *cancellable = data;

    g_return_if_fail (cancellable != NULL);

    g_cancellable_cancel (cancellable);
}

struct TryOpenEBookStruct {
    GError **error;
    EFlag *flag;
    gboolean result;
};

static void
try_open_book_client_cb (GObject *source_object,
                         GAsyncResult *result,
                         gpointer closure)
{
    EBookClient *book_client = E_BOOK_CLIENT (source_object);
    struct TryOpenEBookStruct *data = (struct TryOpenEBookStruct *) closure;
    GError *error = NULL;

    if (!data)
        return;

    e_client_open_finish (E_CLIENT (book_client), result, &error);

    data->result = error == NULL;

    if (!data->result) {
        g_clear_error (data->error);
        g_propagate_error (data->error, error);
    }

    e_flag_set (data->flag);
}

/*
 * try_open_book_client:
 * Tries to open address book asynchronously, but acts as synchronous.
 * The advantage is it checks periodically whether the camel_operation
 * has been canceled or not, and if so, then stops immediately, with
 * result FALSE. Otherwise returns same as e_client_open()
 */
static gboolean
try_open_book_client (EBookClient *book_client,
                      gboolean only_if_exists,
                      GCancellable *cancellable,
                      GError **error)
{
    struct TryOpenEBookStruct data;
    gboolean canceled = FALSE;
    EFlag *flag = e_flag_new ();

    data.error = error;
    data.flag = flag;
    data.result = FALSE;

    e_client_open (
        E_CLIENT (book_client), only_if_exists,
        cancellable, try_open_book_client_cb, &data);

    while (canceled = g_cancellable_is_cancelled (cancellable),
            !canceled && !e_flag_is_set (flag)) {
        GTimeVal wait;

        g_get_current_time (&wait);
        g_time_val_add (&wait, 250000); /* waits 250ms */

        e_flag_timed_wait (flag, &wait);
    }

    if (canceled) {
        g_cancellable_cancel (cancellable);

        g_clear_error (error);
        g_propagate_error (
            error, e_client_error_create (
            E_CLIENT_ERROR_CANCELLED, NULL));
    }

    e_flag_wait (flag);
    e_flag_free (flag);

    return data.result && (!error || !*error);
}

#define NOT_FOUND_BOOK (GINT_TO_POINTER (1))

G_LOCK_DEFINE_STATIC (contact_cache);

/* key is lowercased contact email; value is EBook pointer
 * (just for comparison) where it comes from */
static GHashTable *contact_cache = NULL;

/* key is source ID; value is pointer to EBook */
static GHashTable *emu_books_hash = NULL;

/* key is source ID; value is same pointer as key; this is hash of
 * broken books, which failed to open for some reason */
static GHashTable *emu_broken_books_hash = NULL;

static ESourceList *emu_books_source_list = NULL;

static gboolean
search_address_in_addressbooks (const gchar *address,
                                gboolean local_only,
                                gboolean (*check_contact) (EContact *contact,
                                                           gpointer user_data),
                                gpointer user_data)
{
    gboolean found = FALSE, stop = FALSE, found_any = FALSE;
    gchar *lowercase_addr;
    gpointer ptr;
    EBookQuery *book_query;
    gchar *query;
    GSList *s, *g, *addr_sources = NULL;
    GHook *hook_cancellable;
    GCancellable *cancellable;

    if (!address || !*address)
        return FALSE;

    G_LOCK (contact_cache);

    if (!emu_books_source_list) {
        mail_call_main (
            MAIL_CALL_p_p, (MailMainFunc)
            emu_addr_setup, &emu_books_source_list);
        emu_books_hash = g_hash_table_new_full (
            g_str_hash, g_str_equal, g_free, g_object_unref);
        emu_broken_books_hash = g_hash_table_new_full (
            g_str_hash, g_str_equal, g_free, NULL);
        contact_cache = g_hash_table_new_full (
            g_str_hash, g_str_equal, g_free, NULL);
    }

    if (!emu_books_source_list) {
        G_UNLOCK (contact_cache);
        return FALSE;
    }

    lowercase_addr = g_utf8_strdown (address, -1);
    ptr = g_hash_table_lookup (contact_cache, lowercase_addr);
    if (ptr != NULL && (check_contact == NULL || ptr == NOT_FOUND_BOOK)) {
        g_free (lowercase_addr);
        G_UNLOCK (contact_cache);
        return ptr != NOT_FOUND_BOOK;
    }

    book_query = e_book_query_field_test (E_CONTACT_EMAIL, E_BOOK_QUERY_IS, address);
    query = e_book_query_to_string (book_query);
    e_book_query_unref (book_query);

    for (g = e_source_list_peek_groups (emu_books_source_list);
            g; g = g_slist_next (g)) {
        ESourceGroup *group = g->data;

        if (!group)
            continue;

        if (local_only && !(e_source_group_peek_base_uri (group) &&
            g_str_has_prefix (
            e_source_group_peek_base_uri (group), "local:")))
            continue;

        for (s = e_source_group_peek_sources (group); s; s = g_slist_next (s)) {
            ESource *source = s->data;
            const gchar *completion = e_source_get_property (source, "completion");

            if (completion && g_ascii_strcasecmp (completion, "true") == 0) {
                addr_sources = g_slist_prepend (
                    addr_sources, g_object_ref (source));
            }
        }
    }

    cancellable = g_cancellable_new ();
    hook_cancellable = mail_cancel_hook_add (
        emu_addr_cancel_cancellable, cancellable);

    for (s = addr_sources; !stop && !found && s; s = g_slist_next (s)) {
        ESource *source = s->data;
        GSList *contacts;
        EBookClient *book_client = NULL;
        GHook *hook_stop;
        gboolean cached_book = FALSE;
        const gchar *display_name;
        const gchar *uid;
        GError *err = NULL;

        uid = e_source_peek_uid (source);
        display_name = e_source_peek_name (source);

        /* failed to load this book last time, skip it now */
        if (g_hash_table_lookup (emu_broken_books_hash, uid) != NULL) {
            d(printf ("%s: skipping broken book '%s'\n",
                G_STRFUNC, display_name));
            continue;
        }

        d(printf(" checking '%s'\n", e_source_get_uri(source)));

        hook_stop = mail_cancel_hook_add (emu_addr_cancel_stop, &stop);

        book_client = g_hash_table_lookup (emu_books_hash, uid);
        if (!book_client) {
            book_client = e_book_client_new (source, &err);

            if (book_client == NULL) {
                if (err && (g_error_matches (err, E_CLIENT_ERROR, E_CLIENT_ERROR_CANCELLED) ||
                    g_error_matches (err, G_IO_ERROR, G_IO_ERROR_CANCELLED))) {
                    stop = TRUE;
                } else if (err) {
                    gchar *source_uid;

                    source_uid = g_strdup (uid);

                    g_hash_table_insert (
                        emu_broken_books_hash,
                        source_uid, source_uid);

                    g_warning (
                        "%s: Unable to create addressbook '%s': %s",
                        G_STRFUNC,
                        display_name,
                        err->message);
                }
                g_clear_error (&err);
            } else if (!stop && !try_open_book_client (book_client, TRUE, cancellable, &err)) {
                g_object_unref (book_client);
                book_client = NULL;

                if (err && (g_error_matches (err, E_CLIENT_ERROR, E_CLIENT_ERROR_CANCELLED) ||
                    g_error_matches (err, G_IO_ERROR, G_IO_ERROR_CANCELLED))) {
                    stop = TRUE;
                } else if (err) {
                    gchar *source_uid;

                    source_uid = g_strdup (uid);

                    g_hash_table_insert (
                        emu_broken_books_hash,
                        source_uid, source_uid);

                    g_warning (
                        "%s: Unable to open addressbook '%s': %s",
                        G_STRFUNC,
                        display_name,
                        err->message);
                }
                g_clear_error (&err);
            }
        } else {
            cached_book = TRUE;
        }

        if (book_client && !stop &&
            e_book_client_get_contacts_sync (
            book_client, query, &contacts, cancellable, &err)) {
            if (contacts != NULL) {
                if (!found_any) {
                    g_hash_table_insert (
                        contact_cache,
                        g_strdup (lowercase_addr),
                        book_client);
                }
                found_any = TRUE;

                if (check_contact) {
                    GSList *l;

                    for (l = contacts; l && !found; l = l->next) {
                        EContact *contact = l->data;

                        found = check_contact (contact, user_data);
                    }
                } else {
                    found = TRUE;
                }

                g_slist_foreach (contacts, (GFunc) g_object_unref, NULL);
                g_slist_free (contacts);
            }
        } else if (book_client) {
            stop = stop || (err &&
                (g_error_matches (err, E_CLIENT_ERROR, E_CLIENT_ERROR_CANCELLED) ||
                 g_error_matches (err, G_IO_ERROR, G_IO_ERROR_CANCELLED)));
            if (err && !stop) {
                gchar *source_uid = g_strdup (uid);

                g_hash_table_insert (
                    emu_broken_books_hash,
                    source_uid, source_uid);

                g_warning (
                    "%s: Can't get contacts from '%s': %s",
                    G_STRFUNC,
                    display_name,
                    err->message);
            }
            g_clear_error (&err);
        }

        mail_cancel_hook_remove (hook_stop);

        if (stop && !cached_book && book_client) {
            g_object_unref (book_client);
        } else if (!stop && book_client && !cached_book) {
            g_hash_table_insert (
                emu_books_hash, g_strdup (uid), book_client);
        }
    }

    mail_cancel_hook_remove (hook_cancellable);
    g_object_unref (cancellable);

    g_slist_free_full (addr_sources, (GDestroyNotify) g_object_unref);

    g_free (query);

    if (!found_any) {
        g_hash_table_insert (contact_cache, lowercase_addr, NOT_FOUND_BOOK);
        lowercase_addr = NULL;
    }

    G_UNLOCK (contact_cache);

    g_free (lowercase_addr);

    return found_any;
}

gboolean
em_utils_in_addressbook (CamelInternetAddress *iaddr,
                         gboolean local_only)
{
    const gchar *addr;

    /* TODO: check all addresses? */
    if (iaddr == NULL || !camel_internet_address_get (iaddr, 0, NULL, &addr))
        return FALSE;

    return search_address_in_addressbooks (addr, local_only, NULL, NULL);
}

static gboolean
extract_photo_data (EContact *contact,
                    gpointer user_data)
{
    EContactPhoto **photo = user_data;

    g_return_val_if_fail (contact != NULL, FALSE);
    g_return_val_if_fail (user_data != NULL, FALSE);

    *photo = e_contact_get (contact, E_CONTACT_PHOTO);
    if (!*photo)
        *photo = e_contact_get (contact, E_CONTACT_LOGO);

    return *photo != NULL;
}

typedef struct _PhotoInfo {
    gchar *address;
    EContactPhoto *photo;
} PhotoInfo;

static void
emu_free_photo_info (PhotoInfo *pi)
{
    if (!pi)
        return;

    if (pi->address)
        g_free (pi->address);
    if (pi->photo)
        e_contact_photo_free (pi->photo);
    g_free (pi);
}

G_LOCK_DEFINE_STATIC (photos_cache);
static GSList *photos_cache = NULL; /* list of PhotoInfo-s */

CamelMimePart *
em_utils_contact_photo (CamelInternetAddress *cia,
                        gboolean local_only)
{
    const gchar *addr = NULL;
    CamelMimePart *part = NULL;
    EContactPhoto *photo = NULL;
    GSList *p, *first_not_null = NULL;
    gint count_not_null = 0;

    if (cia == NULL || !camel_internet_address_get (cia, 0, NULL, &addr) || !addr) {
        return NULL;
    }

    G_LOCK (photos_cache);

    /* search a cache first */
    for (p = photos_cache; p; p = p->next) {
        PhotoInfo *pi = p->data;

        if (!pi)
            continue;

        if (pi->photo) {
            if (!first_not_null)
                first_not_null = p;
            count_not_null++;
        }

        if (g_ascii_strcasecmp (addr, pi->address) == 0) {
            photo = pi->photo;
            break;
        }
    }

    /* !p means the address had not been found in the cache */
    if (!p && search_address_in_addressbooks (
            addr, local_only, extract_photo_data, &photo)) {
        PhotoInfo *pi;

        if (photo && photo->type != E_CONTACT_PHOTO_TYPE_INLINED) {
            e_contact_photo_free (photo);
            photo = NULL;
        }

        /* keep only up to 10 photos in memory */
        if (photo && count_not_null >= 10 && first_not_null) {
            pi = first_not_null->data;

            photos_cache = g_slist_remove (photos_cache, pi);

            emu_free_photo_info (pi);
        }

        pi = g_new0 (PhotoInfo, 1);
        pi->address = g_strdup (addr);
        pi->photo = photo;

        photos_cache = g_slist_append (photos_cache, pi);
    }

    /* some photo found, use it */
    if (photo) {
        /* Form a mime part out of the photo */
        part = camel_mime_part_new ();
        camel_mime_part_set_content (part,
                    (const gchar *) photo->data.inlined.data,
                    photo->data.inlined.length, "image/jpeg");
    }

    G_UNLOCK (photos_cache);

    return part;
}

/* list of email addresses (strings) to remove from local cache of photos and
 * contacts, but only if the photo doesn't exist or is an not-found contact */
void
emu_remove_from_mail_cache (const GSList *addresses)
{
    const GSList *a;
    GSList *p;
    CamelInternetAddress *cia;

    cia = camel_internet_address_new ();

    for (a = addresses; a; a = a->next) {
        const gchar *addr = NULL;

        if (!a->data)
            continue;

        if (camel_address_decode ((CamelAddress *) cia, a->data) != -1 &&
            camel_internet_address_get (cia, 0, NULL, &addr) && addr) {
            gchar *lowercase_addr = g_utf8_strdown (addr, -1);

            G_LOCK (contact_cache);
            if (g_hash_table_lookup (contact_cache, lowercase_addr) == NOT_FOUND_BOOK)
                g_hash_table_remove (contact_cache, lowercase_addr);
            G_UNLOCK (contact_cache);

            g_free (lowercase_addr);

            G_LOCK (photos_cache);
            for (p = photos_cache; p; p = p->next) {
                PhotoInfo *pi = p->data;

                if (pi && !pi->photo && g_ascii_strcasecmp (pi->address, addr) == 0) {
                    photos_cache = g_slist_remove (photos_cache, pi);
                    emu_free_photo_info (pi);
                    break;
                }
            }
            G_UNLOCK (photos_cache);
        }
    }

    g_object_unref (cia);
}

void
emu_remove_from_mail_cache_1 (const gchar *address)
{
    GSList *l;

    g_return_if_fail (address != NULL);

    l = g_slist_append (NULL, (gpointer) address);

    emu_remove_from_mail_cache (l);

    g_slist_free (l);
}

/* frees all data created by call of em_utils_in_addressbook() or
 * em_utils_contact_photo() */
void
emu_free_mail_cache (void)
{
    G_LOCK (contact_cache);

    if (emu_books_hash) {
        g_hash_table_destroy (emu_books_hash);
        emu_books_hash = NULL;
    }

    if (emu_broken_books_hash) {
        g_hash_table_destroy (emu_broken_books_hash);
        emu_broken_books_hash = NULL;
    }

    if (emu_books_source_list) {
        g_object_unref (emu_books_source_list);
        emu_books_source_list = NULL;
    }

    if (contact_cache) {
        g_hash_table_destroy (contact_cache);
        contact_cache = NULL;
    }

    G_UNLOCK (contact_cache);

    G_LOCK (photos_cache);

    g_slist_foreach (photos_cache, (GFunc) emu_free_photo_info, NULL);
    g_slist_free (photos_cache);
    photos_cache = NULL;

    G_UNLOCK (photos_cache);
}

static EAccount *
guess_account_from_folder (CamelFolder *folder)
{
    CamelStore *store;
    const gchar *uid;

    store = camel_folder_get_parent_store (folder);
    uid = camel_service_get_uid (CAMEL_SERVICE (store));

    return e_get_account_by_uid (uid);
}

static EAccount *
guess_account_from_message (CamelMimeMessage *message)
{
    const gchar *uid;

    uid = camel_mime_message_get_source (message);

    return (uid != NULL) ? e_get_account_by_uid (uid) : NULL;
}

EAccount *
em_utils_guess_account (CamelMimeMessage *message,
                        CamelFolder *folder)
{
    EAccount *account = NULL;

    g_return_val_if_fail (CAMEL_IS_MIME_MESSAGE (message), NULL);

    if (folder != NULL)
        g_return_val_if_fail (CAMEL_IS_FOLDER (folder), NULL);

    /* check for newsgroup header */
    if (folder != NULL
        && camel_medium_get_header (CAMEL_MEDIUM (message), "Newsgroups"))
        account = guess_account_from_folder (folder);

    /* check for source folder */
    if (account == NULL && folder != NULL)
        account = guess_account_from_folder (folder);

    /* then message source */
    if (account == NULL)
        account = guess_account_from_message (message);

    return account;
}

EAccount *
em_utils_guess_account_with_recipients (CamelMimeMessage *message,
                                        CamelFolder *folder)
{
    EAccount *account = NULL;
    EAccountList *account_list;
    GHashTable *recipients;
    EIterator *iterator;
    CamelInternetAddress *addr;
    const gchar *type;
    const gchar *key;

    /* This policy is subject to debate and tweaking,
     * but please also document the rational here. */

    g_return_val_if_fail (CAMEL_IS_MIME_MESSAGE (message), NULL);

    /* Build a set of email addresses in which to test for membership.
     * Only the keys matter here; the values just need to be non-NULL. */
    recipients = g_hash_table_new (g_str_hash, g_str_equal);

    type = CAMEL_RECIPIENT_TYPE_TO;
    addr = camel_mime_message_get_recipients (message, type);
    if (addr != NULL) {
        gint index = 0;

        while (camel_internet_address_get (addr, index++, NULL, &key))
            g_hash_table_insert (
                recipients, (gpointer) key,
                GINT_TO_POINTER (1));
    }

    type = CAMEL_RECIPIENT_TYPE_CC;
    addr = camel_mime_message_get_recipients (message, type);
    if (addr != NULL) {
        gint index = 0;

        while (camel_internet_address_get (addr, index++, NULL, &key))
            g_hash_table_insert (
                recipients, (gpointer) key,
                GINT_TO_POINTER (1));
    }

    /* First Preference: We were given a folder that maps to an
     * enabled account, and that account's email address appears
     * in the list of To: or Cc: recipients. */

    if (folder != NULL)
        account = guess_account_from_folder (folder);

    if (account == NULL || !account->enabled)
        goto second_preference;

    if ((key = account->id->address) == NULL)
        goto second_preference;

    if (g_hash_table_lookup (recipients, key) != NULL)
        goto exit;

second_preference:

    /* Second Preference: Choose any enabled account whose email
     * address appears in the list to To: or Cc: recipients. */

    account_list = e_get_account_list ();
    iterator = e_list_get_iterator (E_LIST (account_list));

    while (e_iterator_is_valid (iterator)) {
        account = (EAccount *) e_iterator_get (iterator);
        e_iterator_next (iterator);

        if (account == NULL || !account->enabled)
            continue;

        if ((key = account->id->address) == NULL)
            continue;

        if (g_hash_table_lookup (recipients, key) != NULL) {
            g_object_unref (iterator);
            goto exit;
        }
    }
    g_object_unref (iterator);

    /* Last Preference: Defer to em_utils_guess_account(). */
    account = em_utils_guess_account (message, folder);

exit:
    g_hash_table_destroy (recipients);

    return account;
}

static void
cancel_service_connect_cb (GCancellable *cancellable,
                           CamelService *service)
{
    g_return_if_fail (CAMEL_IS_SERVICE (service));

    camel_service_cancel_connect (service);
}

gboolean
em_utils_connect_service_sync (CamelService *service,
                               GCancellable *cancellable,
                               GError **error)
{
    gboolean res;
    gulong handler_id = 0;

    g_return_val_if_fail (CAMEL_IS_SERVICE (service), FALSE);

    if (cancellable != NULL)
        handler_id = g_cancellable_connect (
            cancellable,
            G_CALLBACK (cancel_service_connect_cb),
            service, NULL);

    res = camel_service_connect_sync (service, error);

    if (handler_id)
        g_cancellable_disconnect (cancellable, handler_id);

    return res;
}

gboolean
em_utils_disconnect_service_sync (CamelService *service,
                                  gboolean clean,
                                  GCancellable *cancellable,
                                  GError **error)
{
    gboolean res;
    gulong handler_id = 0;

    g_return_val_if_fail (CAMEL_IS_SERVICE (service), FALSE);

    if (cancellable != NULL)
        handler_id = g_cancellable_connect (
            cancellable,
            G_CALLBACK (cancel_service_connect_cb),
            service, NULL);

    res = camel_service_disconnect_sync (service, clean, error);

    if (handler_id)
        g_cancellable_disconnect (cancellable, handler_id);

    return res;
}

/**
 * em_utils_uids_free:
 * @uids: array of uids
 *
 * Frees the array of uids pointed to by @uids back to the system.
 **/
void
em_utils_uids_free (GPtrArray *uids)
{
    gint i;

    for (i = 0; i < uids->len; i++)
        g_free (uids->pdata[i]);

    g_ptr_array_free (uids, TRUE);
}

/* Returns TRUE if CamelURL points to a local mbox file. */
gboolean
em_utils_is_local_delivery_mbox_file (CamelURL *url)
{
    g_return_val_if_fail (url != NULL, FALSE);

    return g_str_equal (url->protocol, "mbox") &&
        (url->path != NULL) &&
        g_file_test (url->path, G_FILE_TEST_EXISTS) &&
        !g_file_test (url->path, G_FILE_TEST_IS_DIR);
}