/* See LICENSE file for license and copyright information */

#include "dbus-interface.h"
#include "dbus-interface-definitions.h"
#include "synctex.h"
#include "macros.h"
#include "zathura.h"
#include "document.h"
#include "utils.h"
#include "adjustment.h"

#include <girara/session.h>
#include <girara/utils.h>
#include <girara/settings.h>
#include <gio/gio.h>
#include <sys/types.h>
#include <string.h>
#include <unistd.h>

G_DEFINE_TYPE(ZathuraDbus, zathura_dbus, G_TYPE_OBJECT)

/* template for bus name */
static const char DBUS_NAME_TEMPLATE[] = "org.pwmt.zathura.PID-%d";
/* object path */
static const char DBUS_OBJPATH[] = "/org/pwmt/zathura";
/* interface name */
static const char DBUS_INTERFACE[] = "org.pwmt.zathura";

typedef struct private_s {
  zathura_t* zathura;
  GDBusNodeInfo* introspection_data;
  GDBusConnection* connection;
  guint owner_id;
  guint registration_id;
} private_t;

#define GET_PRIVATE(obj) \
  (G_TYPE_INSTANCE_GET_PRIVATE((obj), ZATHURA_TYPE_DBUS, \
                               private_t))

static const GDBusInterfaceVTable interface_vtable;

static void
finalize(GObject* object)
{
  ZathuraDbus* dbus = ZATHURA_DBUS(object);
  private_t* priv   = GET_PRIVATE(dbus);

  if (priv->connection != NULL && priv->registration_id > 0) {
    g_dbus_connection_unregister_object(priv->connection, priv->registration_id);
  }

  if (priv->owner_id > 0) {
    g_bus_unown_name(priv->owner_id);
  }

  if (priv->introspection_data != NULL) {
    g_dbus_node_info_unref(priv->introspection_data);
  }

  G_OBJECT_CLASS(zathura_dbus_parent_class)->finalize(object);
}

static void
zathura_dbus_class_init(ZathuraDbusClass* class)
{
  /* add private members */
  g_type_class_add_private(class, sizeof(private_t));

  /* overwrite methods */
  GObjectClass* object_class = G_OBJECT_CLASS(class);
  object_class->finalize     = finalize;
}

static void
zathura_dbus_init(ZathuraDbus* dbus)
{
  private_t* priv          = GET_PRIVATE(dbus);
  priv->zathura            = NULL;
  priv->introspection_data = NULL;
  priv->connection         = NULL;
  priv->owner_id           = 0;
  priv->registration_id    = 0;
}

static void
bus_acquired(GDBusConnection* connection, const gchar* name, void* data)
{
  girara_debug("Bus acquired at '%s'.", name);

  ZathuraDbus* dbus = data;
  private_t* priv   = GET_PRIVATE(dbus);

  GError* error = NULL;
  priv->registration_id = g_dbus_connection_register_object(connection,
      DBUS_OBJPATH, priv->introspection_data->interfaces[0],
      &interface_vtable, dbus, NULL, &error);
  if (priv->registration_id == 0) {
    girara_warning("Failed to register object on D-Bus connection: %s",
        error->message);
    g_error_free(error);
    return;
  }

  priv->connection = connection;
}

static void
name_acquired(GDBusConnection* UNUSED(connection), const gchar* name,
    void* UNUSED(data))
{
  girara_debug("Acquired '%s' on session bus.", name);
}

static void
name_lost(GDBusConnection* UNUSED(connection), const gchar* name,
    void* UNUSED(data))
{
  girara_debug("Lost connection or failed to acquire '%s' on session bus.",
      name);
}

ZathuraDbus*
zathura_dbus_new(zathura_t* zathura)
{
  GObject* obj = g_object_new(ZATHURA_TYPE_DBUS, NULL);
  if (obj == NULL) {
    return NULL;
  }

  ZathuraDbus* dbus = ZATHURA_DBUS(obj);
  private_t* priv   = GET_PRIVATE(dbus);
  priv->zathura     = zathura;

  GError* error = NULL;
  priv->introspection_data = g_dbus_node_info_new_for_xml(DBUS_INTERFACE_XML, &error);
  if (priv->introspection_data == NULL) {
    girara_warning("Failed to parse introspection data: %s", error->message);
    g_error_free(error);
    g_object_unref(obj);
    return NULL;
  }

  char* well_known_name = g_strdup_printf(DBUS_NAME_TEMPLATE, getpid());
  priv->owner_id = g_bus_own_name(G_BUS_TYPE_SESSION,
      well_known_name, G_BUS_NAME_OWNER_FLAGS_NONE, bus_acquired,
      name_acquired, name_lost, dbus, NULL);
  g_free(well_known_name);

  return dbus;
}

/* D-Bus handler */

static void
highlight_rects(zathura_t* zathura, unsigned int page,
                girara_list_t** rectangles)
{
  const unsigned int number_of_pages = zathura_document_get_number_of_pages(zathura->document);

  for (unsigned int p = 0; p != number_of_pages; ++p) {
    GObject* widget = G_OBJECT(zathura->pages[p]);

    g_object_set(widget, "draw-links", FALSE, "search-results", rectangles[p],
        NULL);
    if (p == page) {
      g_object_set(widget, "search-current", 0, NULL);
    }
  }

  document_draw_search_results(zathura, true);

  if (rectangles[page] == NULL || girara_list_size(rectangles[page]) == 0) {
    page_set(zathura, page);
    return;
  }

  bool search_hadjust = true;
  girara_setting_get(zathura->ui.session, "search-hadjust", &search_hadjust);

  /* compute the position of the center of the page */
  double pos_x = 0;
  double pos_y = 0;
  page_number_to_position(zathura->document, page, 0.5, 0.5, &pos_x, &pos_y);

  /* correction to center the current result                          */
  /* NOTE: rectangle is in viewport units, already scaled and rotated */
  unsigned int cell_height = 0;
  unsigned int cell_width = 0;
  zathura_document_get_cell_size(zathura->document, &cell_height, &cell_width);

  unsigned int doc_height = 0;
  unsigned int doc_width = 0;
  zathura_document_get_document_size(zathura->document, &doc_height, &doc_width);

  /* Need to adjust rectangle to page scale and orientation */
  zathura_page_t* doc_page = zathura_document_get_page(zathura->document, page);
  zathura_rectangle_t* rect = girara_list_nth(rectangles[page], 0);
  zathura_rectangle_t rectangle = recalc_rectangle(doc_page, *rect);

  /* compute the center of the rectangle, which will be aligned to the center
     of the viewport */
  double center_x = (rectangle.x1 + rectangle.x2) / 2;
  double center_y = (rectangle.y1 + rectangle.y2) / 2;

  pos_y += (center_y - (double)cell_height/2) / (double)doc_height;
  if (search_hadjust == true) {
    pos_x += (center_x - (double)cell_width/2) / (double)doc_width;
  }

  /* move to position */
  zathura_jumplist_add(zathura);
  position_set(zathura, pos_x, pos_y);
  zathura_jumplist_add(zathura);
}

static void
handle_method_call(GDBusConnection* UNUSED(connection),
    const gchar* UNUSED(sender), const gchar* object_path,
    const gchar* interface_name,
    const gchar* method_name, GVariant* parameters,
    GDBusMethodInvocation* invocation, void* data)
{
  ZathuraDbus* dbus = data;
  private_t* priv   = GET_PRIVATE(dbus);

  girara_debug("Handling call '%s.%s' on '%s'.", interface_name, method_name,
               object_path);

  /* methods that work without open document */
  if (g_strcmp0(method_name, "OpenDocument") == 0) {
    gchar* filename = NULL;
    gchar* password = NULL;
    gint page = ZATHURA_PAGE_NUMBER_UNSPECIFIED;
    g_variant_get(parameters, "(ssi)", &filename, &password, &page);

    document_close(priv->zathura, false);
    const bool ret = document_open(priv->zathura, filename,
        strlen(password) > 0 ? password : NULL, page);
    g_free(filename);
    g_free(password);

    GVariant* result = g_variant_new("(b)", ret);
    g_dbus_method_invocation_return_value(invocation, result);
    return;
  } else if (g_strcmp0(method_name, "CloseDocument") == 0) {
    const bool ret = document_close(priv->zathura, false);

    GVariant* result = g_variant_new("(b)", ret);
    g_dbus_method_invocation_return_value(invocation, result);
    return;
  }

  if (priv->zathura->document == NULL) {
    g_dbus_method_invocation_return_dbus_error(invocation,
        "org.pwmt.zathura.NoOpenDocumen", "No document has been opened.");
    return;
  }

  const unsigned int number_of_pages = zathura_document_get_number_of_pages(priv->zathura->document);

  /* methods that require an open document */
  if (g_strcmp0(method_name, "GotoPage") == 0) {
    guint page = 0;
    g_variant_get(parameters, "(u)", &page);

    bool ret = true;
    if (page >= number_of_pages) {
      ret = false;
    } else {
      page_set(priv->zathura, page);
    }

    GVariant* result = g_variant_new("(b)", ret);
    g_dbus_method_invocation_return_value(invocation, result);
  } else if (g_strcmp0(method_name, "HighlightRects") == 0) {
    guint page = 0;
    GVariantIter* iter = NULL;
    GVariantIter* secondary_iter = NULL;
    g_variant_get(parameters, "(ua(dddd)a(udddd))", &page, &iter,
        &secondary_iter);

    if (page >= number_of_pages) {
      GVariant* result = g_variant_new("(b)", false);
      g_variant_iter_free(iter);
      g_variant_iter_free(secondary_iter);
      g_dbus_method_invocation_return_value(invocation, result);
      return;
    }

    /* get rectangles */
    girara_list_t** rectangles = g_malloc0(number_of_pages * sizeof(girara_list_t*));
    rectangles[page] = girara_list_new2(g_free);

    zathura_rectangle_t temp_rect;
    while (g_variant_iter_loop(iter, "(dddd)", &temp_rect.x1, &temp_rect.x2,
          &temp_rect.y1, &temp_rect.y2)) {
      zathura_rectangle_t* rect = g_malloc0(sizeof(zathura_rectangle_t));
      *rect = temp_rect;
      girara_list_append(rectangles[page], rect);
    }
    g_variant_iter_free(iter);

    /* get secondary rectangles */
    guint temp_page = 0;
    while (g_variant_iter_loop(secondary_iter, "(udddd)", &temp_page,
          &temp_rect.x1, &temp_rect.x2, &temp_rect.y1, &temp_rect.y2)) {
      if (temp_page >= number_of_pages) {
        /* error out here? */
        continue;
      }

      if (rectangles[temp_page] == NULL) {
        rectangles[temp_page] = girara_list_new2(g_free);
      }

      zathura_rectangle_t* rect = g_malloc0(sizeof(zathura_rectangle_t));
      *rect = temp_rect;
      girara_list_append(rectangles[temp_page], rect);
    }
    g_variant_iter_free(secondary_iter);

    highlight_rects(priv->zathura, page, rectangles);
    g_free(rectangles);

    GVariant* result = g_variant_new("(b)", true);
    g_dbus_method_invocation_return_value(invocation, result);
  }
}

static GVariant*
handle_get_property(GDBusConnection* UNUSED(connection),
    const gchar* UNUSED(sender), const gchar* UNUSED(object_path),
    const gchar* UNUSED(interface_name), const gchar* property_name,
    GError** error, void* data)
{
  ZathuraDbus* dbus = data;
  private_t* priv   = GET_PRIVATE(dbus);

  if (g_strcmp0(property_name, "filename") == 0) {
    if (priv->zathura->document == NULL) {
      g_set_error(error, G_IO_ERROR, G_IO_ERROR_FAILED, "No document open.");
    } else {
      return g_variant_new_string(zathura_document_get_path(priv->zathura->document));
    }
  }

  return NULL;
}

static const GDBusInterfaceVTable interface_vtable =
{
  .method_call  = handle_method_call,
  .get_property = handle_get_property,
  .set_property = NULL
};

static const unsigned int TIMEOUT = 3000;

bool
zathura_dbus_goto_page_and_highlight(const char* filename, unsigned int page,
    girara_list_t* rectangles, girara_list_t* secondary_rects)
{
  /* note: page is [1, number_of_pages] here */

  if (filename == NULL) {
    return false;
  }

  GError* error = NULL;
  GDBusConnection* connection = g_bus_get_sync(G_BUS_TYPE_SESSION,
      NULL, &error);
  if (connection == NULL) {
    girara_error("Could not connect to session bus: %s", error->message);
    g_error_free(error);
    return false;
  }

  GVariant* vnames = g_dbus_connection_call_sync(connection,
      "org.freedesktop.DBus", "/org/freedesktop/DBus", "org.freedesktop.DBus",
      "ListNames", NULL, G_VARIANT_TYPE("(as)"), G_DBUS_CALL_FLAGS_NONE,
      TIMEOUT, NULL, &error);
  if (vnames == NULL) {
    girara_error("Could not list available names: %s", error->message);
    g_error_free(error);
    g_object_unref(connection);
    return false;
  }

  GVariantIter* iter = NULL;
  g_variant_get(vnames, "(as)", &iter);

  gchar* name = NULL;
  bool found_one = false;
  while (g_variant_iter_loop(iter, "s", &name) == TRUE) {
    if (g_str_has_prefix(name, "org.pwmt.zathura.PID") == FALSE) {
      continue;
    }
    girara_debug("Found name: %s", name);

    GVariant* vfilename = g_dbus_connection_call_sync(connection,
      name, DBUS_OBJPATH, "org.freedesktop.DBus.Properties",
      "Get", g_variant_new("(ss)", DBUS_INTERFACE, "filename"),
      G_VARIANT_TYPE("(v)"), G_DBUS_CALL_FLAGS_NONE,
      TIMEOUT, NULL, &error);
    if (vfilename == NULL) {
      girara_error("Failed to query 'filename' property from '%s': %s",
          name, error->message);
      g_error_free(error);
      continue;
    }

    GVariant* tmp = NULL;
    g_variant_get(vfilename, "(v)", &tmp);
    gchar* remote_filename = g_variant_dup_string(tmp, NULL);
    girara_debug("Filename from '%s': %s", name, remote_filename);
    g_variant_unref(tmp);
    g_variant_unref(vfilename);

    if (g_strcmp0(filename, remote_filename) != 0) {
      g_free(remote_filename);
      continue;
    }

    g_free(remote_filename);
    found_one = true;

    GVariantBuilder* builder = g_variant_builder_new(G_VARIANT_TYPE("a(dddd)"));
    if (rectangles != NULL) {
      GIRARA_LIST_FOREACH(rectangles, zathura_rectangle_t*, iter, rect)
        g_variant_builder_add(builder, "(dddd)", rect->x1, rect->x2, rect->y1,
            rect->y2);
      GIRARA_LIST_FOREACH_END(rectangles, zathura_rectangle_t*, iter, rect);
    }

    GVariantBuilder* second_builder = g_variant_builder_new(G_VARIANT_TYPE("a(udddd)"));
    if (secondary_rects != NULL) {
      GIRARA_LIST_FOREACH(secondary_rects, synctex_page_rect_t*, iter, rect)
        g_variant_builder_add(second_builder, "(udddd)", rect->page,
            rect->rect.x1, rect->rect.x2, rect->rect.y1, rect->rect.y2);
      GIRARA_LIST_FOREACH_END(secondary_rects, synctex_page_rect_t*, iter, rect);
    }

    GVariant* ret = g_dbus_connection_call_sync(connection,
      name, DBUS_OBJPATH, DBUS_INTERFACE, "HighlightRects",
      g_variant_new("(ua(dddd)a(udddd))", page, builder, second_builder),
      G_VARIANT_TYPE("(b)"), G_DBUS_CALL_FLAGS_NONE, TIMEOUT, NULL, &error);
    g_variant_builder_unref(builder);
    if (ret == NULL) {
      girara_error("Failed to run HighlightRects on '%s': %s", name, error->message);
      g_error_free(error);
    } else {
      g_variant_unref(ret);
    }
  }
  g_variant_iter_free(iter);
  g_variant_unref(vnames);
  g_object_unref(connection);

  return found_one;
}

bool
zathura_dbus_synctex_position(const char* filename, const char* position)
{
  if (filename == NULL || position == NULL) {
    return false;
  }

  unsigned int page = 0;
  girara_list_t* secondary_rects = NULL;
  girara_list_t* rectangles = synctex_rectangles_from_position(filename,
      position, &page, &secondary_rects);
  if (rectangles == NULL) {
    return false;
  }

  const bool ret = zathura_dbus_goto_page_and_highlight(filename, page,
      rectangles, secondary_rects);
  girara_list_free(rectangles);
  girara_list_free(secondary_rects);
  return ret;
}