/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * Copyright (C) 2007-2010 Collabora Ltd.
 *
 * This library 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 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Authors: Xavier Claessens <xclaesse@gmail.com>
 *          Travis Reitter <travis.reitter@collabora.co.uk>
 */

#include <config.h>

#include <string.h>

#include <telepathy-glib/account-manager.h>
#include <telepathy-glib/enums.h>
#include <telepathy-glib/proxy-subclass.h>
#include <telepathy-glib/util.h>

#include <folks/folks.h>

#include <extensions/extensions.h>

#include "empathy-individual-manager.h"
#include "empathy-marshal.h"
#include "empathy-utils.h"

#define DEBUG_FLAG EMPATHY_DEBUG_CONTACT
#include "empathy-debug.h"

#define GET_PRIV(obj) EMPATHY_GET_PRIV (obj, EmpathyIndividualManager)

/* This class only stores and refs Individuals who contain an EmpathyContact.
 *
 * This class merely forwards along signals from the aggregator and individuals
 * and wraps aggregator functions for other client code. */
typedef struct
{
  FolksIndividualAggregator *aggregator;
  GHashTable *individuals; /* Individual.id -> Individual */
} EmpathyIndividualManagerPriv;

enum
{
  FAVOURITES_CHANGED,
  GROUPS_CHANGED,
  MEMBERS_CHANGED,
  LAST_SIGNAL
};

static guint signals[LAST_SIGNAL] = { 0 };

G_DEFINE_TYPE (EmpathyIndividualManager, empathy_individual_manager,
    G_TYPE_OBJECT);

static EmpathyIndividualManager *manager_singleton = NULL;

static void
individual_group_changed_cb (FolksIndividual *individual,
    gchar *group,
    gboolean is_member,
    EmpathyIndividualManager *self)
{
  g_signal_emit (self, signals[GROUPS_CHANGED], 0, individual, group,
      is_member);
}

static void
individual_notify_is_favourite_cb (FolksIndividual *individual,
    GParamSpec *pspec,
    EmpathyIndividualManager *self)
{
  gboolean is_favourite = folks_favouritable_get_is_favourite (
      FOLKS_FAVOURITABLE (individual));
  g_signal_emit (self, signals[FAVOURITES_CHANGED], 0, individual,
      is_favourite);
}

static void
add_individual (EmpathyIndividualManager *self, FolksIndividual *individual)
{
  EmpathyIndividualManagerPriv *priv = GET_PRIV (self);

  g_hash_table_insert (priv->individuals,
      (gpointer) folks_individual_get_id (individual),
      g_object_ref (individual));

  g_signal_connect (individual, "group-changed",
      G_CALLBACK (individual_group_changed_cb), self);
  g_signal_connect (individual, "notify::is-favourite",
      G_CALLBACK (individual_notify_is_favourite_cb), self);
}

static void
remove_individual (EmpathyIndividualManager *self, FolksIndividual *individual)
{
  EmpathyIndividualManagerPriv *priv = GET_PRIV (self);

  g_signal_handlers_disconnect_by_func (individual,
      individual_group_changed_cb, self);
  g_signal_handlers_disconnect_by_func (individual,
      individual_notify_is_favourite_cb, self);

  g_hash_table_remove (priv->individuals, folks_individual_get_id (individual));
}

/* This is emitted for *all* individuals in the individual aggregator (not
 * just the ones we keep a reference to), to allow for the case where a new
 * individual doesn't contain an EmpathyContact, but later has a persona added
 * which does. */
static void
individual_notify_personas_cb (FolksIndividual *individual,
    GParamSpec *pspec,
    EmpathyIndividualManager *self)
{
  EmpathyIndividualManagerPriv *priv = GET_PRIV (self);

  const gchar *id = folks_individual_get_id (individual);
  gboolean has_contact = empathy_folks_individual_contains_contact (individual);
  gboolean had_contact = (g_hash_table_lookup (priv->individuals,
      id) != NULL) ? TRUE : FALSE;

  if (had_contact == TRUE && has_contact == FALSE)
    {
      GList *removed = NULL;

      /* The Individual has lost its EmpathyContact */
      removed = g_list_prepend (removed, individual);
      g_signal_emit (self, signals[MEMBERS_CHANGED], 0, NULL, NULL, removed,
          TP_CHANNEL_GROUP_CHANGE_REASON_NONE /* FIXME */);
      g_list_free (removed);

      remove_individual (self, individual);
    }
  else if (had_contact == FALSE && has_contact == TRUE)
    {
      GList *added = NULL;

      /* The Individual has gained its first EmpathyContact */
      add_individual (self, individual);

      added = g_list_prepend (added, individual);
      g_signal_emit (self, signals[MEMBERS_CHANGED], 0, NULL, added, NULL,
          TP_CHANNEL_GROUP_CHANGE_REASON_NONE /* FIXME */);
      g_list_free (added);
    }
}

static void
aggregator_individuals_changed_cb (FolksIndividualAggregator *aggregator,
    GList *added,
    GList *removed,
    const char *message,
    FolksPersona *actor,
    guint reason,
    EmpathyIndividualManager *self)
{
  EmpathyIndividualManagerPriv *priv = GET_PRIV (self);
  GList *l, *added_filtered = NULL;

  /* Handle the removals first, as one of the added Individuals might have the
   * same ID as one of the removed Individuals (due to linking). */
  for (l = removed; l; l = l->next)
    {
      FolksIndividual *ind = FOLKS_INDIVIDUAL (l->data);

      g_signal_handlers_disconnect_by_func (ind,
          individual_notify_personas_cb, self);

      if (g_hash_table_lookup (priv->individuals,
          folks_individual_get_id (ind)) != NULL)
        remove_individual (self, ind);
    }

  /* Filter the individuals for ones which contain EmpathyContacts */
  for (l = added; l; l = l->next)
    {
      FolksIndividual *ind = FOLKS_INDIVIDUAL (l->data);

      g_signal_connect (ind, "notify::personas",
          G_CALLBACK (individual_notify_personas_cb), self);

      if (empathy_folks_individual_contains_contact (ind) == TRUE)
        {
          add_individual (self, ind);
          added_filtered = g_list_prepend (added_filtered, ind);
        }
    }

  /* Bail if we have no individuals left */
  if (added_filtered == NULL && removed == NULL)
    return;

  added_filtered = g_list_reverse (added_filtered);

  g_signal_emit (self, signals[MEMBERS_CHANGED], 0, message,
      added_filtered, removed,
      tp_channel_group_change_reason_from_folks_groups_change_reason (reason),
      TRUE);

  g_list_free (added_filtered);
}

static void
individual_manager_dispose (GObject *object)
{
  EmpathyIndividualManagerPriv *priv = GET_PRIV (object);

  g_hash_table_destroy (priv->individuals);
  tp_clear_object (&priv->aggregator);

  G_OBJECT_CLASS (empathy_individual_manager_parent_class)->dispose (object);
}

static GObject *
individual_manager_constructor (GType type,
    guint n_props,
    GObjectConstructParam *props)
{
  GObject *retval;

  if (manager_singleton)
    {
      retval = g_object_ref (manager_singleton);
    }
  else
    {
      retval =
          G_OBJECT_CLASS (empathy_individual_manager_parent_class)->
          constructor (type, n_props, props);

      manager_singleton = EMPATHY_INDIVIDUAL_MANAGER (retval);
      g_object_add_weak_pointer (retval, (gpointer) & manager_singleton);
    }

  return retval;
}

/**
 * empathy_individual_manager_initialized:
 *
 * Reports whether or not the singleton has already been created.
 *
 * There can be instances where you want to access the #EmpathyIndividualManager
 * only if it has been set up for this process.
 *
 * Returns: %TRUE if the #EmpathyIndividualManager singleton has previously
 * been initialized.
 */
gboolean
empathy_individual_manager_initialized (void)
{
  return (manager_singleton != NULL);
}

static void
empathy_individual_manager_class_init (EmpathyIndividualManagerClass *klass)
{
  GObjectClass *object_class = G_OBJECT_CLASS (klass);

  object_class->dispose = individual_manager_dispose;
  object_class->constructor = individual_manager_constructor;

  signals[GROUPS_CHANGED] =
      g_signal_new ("groups-changed",
          G_TYPE_FROM_CLASS (klass),
          G_SIGNAL_RUN_LAST,
          0,
          NULL, NULL,
          _empathy_marshal_VOID__OBJECT_STRING_BOOLEAN,
          G_TYPE_NONE, 3, FOLKS_TYPE_INDIVIDUAL, G_TYPE_STRING, G_TYPE_BOOLEAN);

  signals[FAVOURITES_CHANGED] =
      g_signal_new ("favourites-changed",
          G_TYPE_FROM_CLASS (klass),
          G_SIGNAL_RUN_LAST,
          0,
          NULL, NULL,
          _empathy_marshal_VOID__OBJECT_BOOLEAN,
          G_TYPE_NONE, 2, FOLKS_TYPE_INDIVIDUAL, G_TYPE_BOOLEAN);

  signals[MEMBERS_CHANGED] =
      g_signal_new ("members-changed",
          G_TYPE_FROM_CLASS (klass),
          G_SIGNAL_RUN_LAST,
          0,
          NULL, NULL,
          _empathy_marshal_VOID__STRING_OBJECT_OBJECT_UINT,
          G_TYPE_NONE,
          4, G_TYPE_STRING, G_TYPE_POINTER, G_TYPE_POINTER, G_TYPE_UINT);

  g_type_class_add_private (object_class,
      sizeof (EmpathyIndividualManagerPriv));
}

static void
empathy_individual_manager_init (EmpathyIndividualManager *self)
{
  EmpathyIndividualManagerPriv *priv = G_TYPE_INSTANCE_GET_PRIVATE (self,
      EMPATHY_TYPE_INDIVIDUAL_MANAGER, EmpathyIndividualManagerPriv);

  self->priv = priv;
  priv->individuals = g_hash_table_new_full (g_str_hash, g_str_equal,
      NULL, g_object_unref);

  priv->aggregator = folks_individual_aggregator_new ();
  g_signal_connect (priv->aggregator, "individuals-changed",
      G_CALLBACK (aggregator_individuals_changed_cb), self);
  folks_individual_aggregator_prepare (priv->aggregator, NULL, NULL);
}

EmpathyIndividualManager *
empathy_individual_manager_dup_singleton (void)
{
  return g_object_new (EMPATHY_TYPE_INDIVIDUAL_MANAGER, NULL);
}

GList *
empathy_individual_manager_get_members (EmpathyIndividualManager *self)
{
  EmpathyIndividualManagerPriv *priv = GET_PRIV (self);

  g_return_val_if_fail (EMPATHY_IS_INDIVIDUAL_MANAGER (self), NULL);

  return g_hash_table_get_values (priv->individuals);
}

FolksIndividual *
empathy_individual_manager_lookup_member (EmpathyIndividualManager *self,
    const gchar *id)
{
  EmpathyIndividualManagerPriv *priv = GET_PRIV (self);

  g_return_val_if_fail (EMPATHY_IS_INDIVIDUAL_MANAGER (self), NULL);

  return g_hash_table_lookup (priv->individuals, id);
}

static void
aggregator_add_persona_from_details_cb (GObject *source,
    GAsyncResult *result,
    gpointer user_data)
{
  FolksIndividualAggregator *aggregator = FOLKS_INDIVIDUAL_AGGREGATOR (source);
  EmpathyContact *contact = EMPATHY_CONTACT (user_data);
  FolksPersona *persona;
  GError *error = NULL;

  persona = folks_individual_aggregator_add_persona_from_details_finish (
      aggregator, result, &error);
  if (error != NULL)
    {
      g_warning ("failed to add individual from contact: %s", error->message);
      g_clear_error (&error);
    }

  /* The persona can be NULL even if there wasn't an error, if the persona was
   * already in the contact list */
  if (persona != NULL)
    {
      /* Set the contact's persona */
      empathy_contact_set_persona (contact, persona);
      g_object_unref (persona);
    }

  g_object_unref (contact);
}

void
empathy_individual_manager_add_from_contact (EmpathyIndividualManager *self,
    EmpathyContact *contact)
{
  EmpathyIndividualManagerPriv *priv;
  FolksBackendStore *backend_store;
  FolksBackend *backend;
  FolksPersonaStore *persona_store;
  GHashTable* details, *persona_stores;
  TpAccount *account;
  const gchar *store_id;

  g_return_if_fail (EMPATHY_IS_INDIVIDUAL_MANAGER (self));
  g_return_if_fail (EMPATHY_IS_CONTACT (contact));

  priv = GET_PRIV (self);

  /* We need to ref the contact since otherwise its linked TpHandle will be
   * destroyed. */
  g_object_ref (contact);

  DEBUG ("adding individual from contact %s (%s)",
      empathy_contact_get_id (contact), empathy_contact_get_alias (contact));

  account = empathy_contact_get_account (contact);
  store_id = tp_proxy_get_object_path (TP_PROXY (account));

  /* Get the persona store to use */
  backend_store = folks_backend_store_dup ();
  backend =
      folks_backend_store_dup_backend_by_name (backend_store, "telepathy");

  if (backend == NULL)
    {
      g_warning ("Failed to add individual from contact: couldn't get "
          "'telepathy' backend");
      goto finish;
    }

  persona_stores = folks_backend_get_persona_stores (backend);
  persona_store = g_hash_table_lookup (persona_stores, store_id);

  if (persona_store == NULL)
    {
      g_warning ("Failed to add individual from contact: couldn't get persona "
          "store '%s'", store_id);
      goto finish;
    }

  details = tp_asv_new (
      "contact", G_TYPE_STRING, empathy_contact_get_id (contact),
      NULL);

  folks_individual_aggregator_add_persona_from_details (
      priv->aggregator, NULL, persona_store, details,
      aggregator_add_persona_from_details_cb, contact);

  g_hash_table_destroy (details);

finish:
  tp_clear_object (&backend);
  tp_clear_object (&backend_store);
}

static void
aggregator_remove_individual_cb (GObject *source,
    GAsyncResult *result,
    gpointer user_data)
{
  FolksIndividualAggregator *aggregator = FOLKS_INDIVIDUAL_AGGREGATOR (source);
  GError *error = NULL;

  folks_individual_aggregator_remove_individual_finish (
      aggregator, result, &error);
  if (error != NULL)
    {
      g_warning ("failed to remove individual: %s", error->message);
      g_clear_error (&error);
    }
}

/**
 * Removes the inner contact from the server (and thus the Individual). Not
 * meant for de-shelling inner personas from an Individual.
 */
void
empathy_individual_manager_remove (EmpathyIndividualManager *self,
    FolksIndividual *individual,
    const gchar *message)
{
  EmpathyIndividualManagerPriv *priv;

  g_return_if_fail (EMPATHY_IS_INDIVIDUAL_MANAGER (self));
  g_return_if_fail (FOLKS_IS_INDIVIDUAL (individual));

  priv = GET_PRIV (self);

  DEBUG ("removing individual %s (%s)",
      folks_individual_get_id (individual),
      folks_aliasable_get_alias (FOLKS_ALIASABLE (individual)));

  folks_individual_aggregator_remove_individual (priv->aggregator, individual,
      aggregator_remove_individual_cb, self);
}

static void
groups_change_group_cb (GObject *source,
    GAsyncResult *result,
    gpointer user_data)
{
  FolksGroupable *groupable = FOLKS_GROUPABLE (source);
  GError *error = NULL;

  folks_groupable_change_group_finish (groupable, result, &error);
  if (error != NULL)
    {
      g_warning ("failed to change group: %s", error->message);
      g_clear_error (&error);
    }
}

static void
remove_group_cb (const gchar *id,
    FolksIndividual *individual,
    const gchar *group)
{
  folks_groupable_change_group (FOLKS_GROUPABLE (individual), group, FALSE,
      groups_change_group_cb, NULL);
}

void
empathy_individual_manager_remove_group (EmpathyIndividualManager *manager,
    const gchar *group)
{
  EmpathyIndividualManagerPriv *priv;

  g_return_if_fail (EMPATHY_IS_INDIVIDUAL_MANAGER (manager));
  g_return_if_fail (group != NULL);

  priv = GET_PRIV (manager);

  DEBUG ("removing group %s", group);

  /* Remove every individual from the group */
  g_hash_table_foreach (priv->individuals, (GHFunc) remove_group_cb,
      (gpointer) group);
}

static void
link_personas_cb (FolksIndividualAggregator *aggregator,
    GAsyncResult *async_result,
    gpointer user_data)
{
  GError *error = NULL;

  folks_individual_aggregator_link_personas_finish (aggregator, async_result,
      &error);

  if (error != NULL)
    {
      g_warning ("Failed to link personas: %s", error->message);
      g_clear_error (&error);
    }
}

void
empathy_individual_manager_link_personas (EmpathyIndividualManager *self,
    GList *personas)
{
  EmpathyIndividualManagerPriv *priv;

  g_return_if_fail (EMPATHY_IS_INDIVIDUAL_MANAGER (self));
  g_return_if_fail (personas != NULL);

  priv = GET_PRIV (self);

  DEBUG ("Linking %u personas", g_list_length (personas));

  folks_individual_aggregator_link_personas (priv->aggregator, personas,
      (GAsyncReadyCallback) link_personas_cb, NULL);
}

static void
unlink_individual_cb (FolksIndividualAggregator *aggregator,
    GAsyncResult *async_result,
    gpointer user_data)
{
  GError *error = NULL;

  folks_individual_aggregator_unlink_individual_finish (aggregator,
      async_result, &error);

  if (error != NULL)
    {
      g_warning ("Failed to unlink individual: %s", error->message);
      g_clear_error (&error);
    }
}

void
empathy_individual_manager_unlink_individual (EmpathyIndividualManager *self,
    FolksIndividual *individual)
{
  EmpathyIndividualManagerPriv *priv;

  g_return_if_fail (EMPATHY_IS_INDIVIDUAL_MANAGER (self));
  g_return_if_fail (FOLKS_IS_INDIVIDUAL (individual));

  priv = GET_PRIV (self);

  DEBUG ("Unlinking individual '%s'", folks_individual_get_id (individual));

  folks_individual_aggregator_unlink_individual (priv->aggregator, individual,
      (GAsyncReadyCallback) unlink_individual_cb, NULL);
}