#include "modules/bluetooth.hpp"

#include <algorithm>
#include <spdlog/spdlog.h>
#include <fmt/format.h>

namespace {

using GDBusManager = std::unique_ptr<GDBusObjectManager, void (*)(GDBusObjectManager*)>;

auto generateManager() -> GDBusManager {
  GError* error = nullptr;
  GDBusObjectManager* manager = g_dbus_object_manager_client_new_for_bus_sync(
    G_BUS_TYPE_SYSTEM,
    GDBusObjectManagerClientFlags::G_DBUS_OBJECT_MANAGER_CLIENT_FLAGS_DO_NOT_AUTO_START,
    "org.bluez",
    "/",
    NULL,
    NULL,
    NULL,
    NULL,
    &error
  );

  if (error) {
    spdlog::error("g_dbus_object_manager_client_new_for_bus_sync() failed: {}", error->message);
    g_error_free(error);
  }

  auto destructor = [](GDBusObjectManager* manager) {
    if (manager) {
      g_object_unref(manager);
    }
  };

  return GDBusManager{manager, destructor};
}

auto getBoolProperty(GDBusProxy* proxy, const char* property_name) -> bool {
  auto gvar = g_dbus_proxy_get_cached_property(proxy, property_name);
  if (gvar) {
    bool property_value = g_variant_get_boolean(gvar);
    g_variant_unref(gvar);
    return property_value;
  }

  spdlog::error("getBoolProperty() failed: doesn't have property {}", property_name);
  return false;
}

auto getOptionalStringProperty(GDBusProxy* proxy, const char* property_name) -> std::optional<std::string> {
  auto gvar = g_dbus_proxy_get_cached_property(proxy, property_name);
  if (gvar) {
    std::string property_value = g_variant_get_string(gvar, NULL);
    g_variant_unref(gvar);
    return property_value;
  }

  return std::nullopt;
}

auto getStringProperty(GDBusProxy* proxy, const char* property_name) -> std::string {
  auto property_value = getOptionalStringProperty(proxy, property_name);
  if (!property_value.has_value()) {
    spdlog::error("getStringProperty() failed: doesn't have property {}", property_name);
  }
  return property_value.value_or("");
}

auto getUcharProperty(GDBusProxy* proxy, const char* property_name) -> unsigned char {
  auto gvar = g_dbus_proxy_get_cached_property(proxy, property_name);
  if (gvar) {
    unsigned char property_value;
    g_variant_get(gvar, "y", &property_value);
    g_variant_unref(gvar);

    return property_value;
  }

  spdlog::error("getUcharProperty() failed: doesn't have property {}", property_name);
  return 0;
}

}  // namespace

waybar::modules::Bluetooth::Bluetooth(const std::string& id, const Json::Value& config)
    : ALabel(config, "bluetooth", id, " {status}", 10),
#ifdef WANT_RFKILL
      rfkill_{RFKILL_TYPE_BLUETOOTH},
#endif
      manager_(generateManager()) {

  if (config_["format-device-preference"].isArray()) {
    std::transform(config_["format-device-preference"].begin(),
                   config_["format-device-preference"].end(),
                   std::back_inserter(device_preference_),
                   [](auto x){ return x.asString(); });
  }

  // NOTE: assumption made that the adapter that is selcected stays unchanged
  // for duration of the module
  if (!findCurAdapter(cur_adapter_)) {
    if (config_["adapter-alias"].isString()) {
      spdlog::error("find_cur_adapter() failed: no bluetooth adapter found with alias '{}'", config_["adapter-alias"].asString());
    } else {
      spdlog::error("find_cur_adapter() failed: no bluetooth adapter found");
    }
    return;
  }
  findConnectedDevices(cur_adapter_.path, connected_devices_);

  g_signal_connect(manager_.get(), "interface-proxy-properties-changed", G_CALLBACK(onInterfaceProxyPropertiesChanged), this);
  g_signal_connect(manager_.get(), "interface-added", G_CALLBACK(onInterfaceAddedOrRemoved), this);
  g_signal_connect(manager_.get(), "interface-removed", G_CALLBACK(onInterfaceAddedOrRemoved), this);
#ifdef WANT_RFKILL
  rfkill_.on_update.connect(sigc::hide(sigc::mem_fun(*this, &Bluetooth::update)));
#endif

  dp.emit();
}

auto waybar::modules::Bluetooth::update() -> void {
  // focussed device is either:
  // - the first device in the device_preference_ list that is connected to the
  //   current adapter (if none fallback to last connected device)
  // - it is the last device that connected to the current adapter
  if (!connected_devices_.empty()) {
    bool preferred_device_connected = false;
    if (!device_preference_.empty()) {
      for (const std::string& device_alias : device_preference_) {
        auto it = std::find_if(connected_devices_.begin(), connected_devices_.end(), [device_alias](auto device){ return device_alias == device.alias; });
        if (it != connected_devices_.end()) {
          preferred_device_connected = true;
          cur_focussed_device_ = *it;
          break;
        }
      }
    }
    if (!preferred_device_connected) {
      cur_focussed_device_ = connected_devices_.back();
    }
  }

  std::string state;
  std::string tooltip_format;
  if (!cur_adapter_.powered)
    state = "off";
  else if (!connected_devices_.empty())
    state = "connected";
  else
    state = "on";
#ifdef WANT_RFKILL
  if (rfkill_.getState())
    state = "disabled";
#endif

  if (!alt_) {
    if (state == "connected" && cur_focussed_device_.battery_percentage.has_value() && config_["format-connected-battery"].isString()) {
      format_ = config_["format-connected-battery"].asString();
    } else if (config_["format-" + state].isString()) {
      format_ = config_["format-" + state].asString();
    } else if (config_["format"].isString()) {
      format_ = config_["format"].asString();
    } else {
      format_ = default_format_;
    }
  }
  if (config_["tooltip-format-" + state].isString()) {
    tooltip_format = config_["tooltip-format-" + state].asString();
  } else if (config_["tooltip-format"].isString()) {
    tooltip_format = config_["tooltip-format"].asString();
  }

  auto update_style_context = [this](const std::string& style_class, bool in_next_state) {
    if (in_next_state && !label_.get_style_context()->has_class(style_class)) {
      label_.get_style_context()->add_class(style_class);
    } else if (!in_next_state && label_.get_style_context()->has_class(style_class)) {
      label_.get_style_context()->remove_class(style_class);
    }
  };
  update_style_context("discoverable", cur_adapter_.discoverable);
  update_style_context("discovering", cur_adapter_.discovering);
  update_style_context("pairable", cur_adapter_.pairable);
  if (!state_.empty()) {
    update_style_context(state_, false);
  }
  update_style_context(state, true);
  state_ = state;

  label_.set_markup(fmt::format(format_,
        fmt::arg("status", state_),
        fmt::arg("num_connections", connected_devices_.size()),
        fmt::arg("adapter_address", cur_adapter_.address),
        fmt::arg("adapter_address_type", cur_adapter_.address_type),
        fmt::arg("adapter_alias", cur_adapter_.alias),
        fmt::arg("device_address", cur_focussed_device_.address),
        fmt::arg("device_address_type", cur_focussed_device_.address_type),
        fmt::arg("device_alias", cur_focussed_device_.alias),
        fmt::arg("device_battery_percentage", cur_focussed_device_.battery_percentage.value_or(0))
        ));

  // TODO: make possible to show information about all connected devices in the tooltip
  if (tooltipEnabled()) {
    label_.set_tooltip_text(fmt::format(tooltip_format,
          fmt::arg("status", state_),
          fmt::arg("num_connections", connected_devices_.size()),
          fmt::arg("adapter_address", cur_adapter_.address),
          fmt::arg("adapter_address_type", cur_adapter_.address_type),
          fmt::arg("adapter_alias", cur_adapter_.alias),
          fmt::arg("device_address", cur_focussed_device_.address),
          fmt::arg("device_address_type", cur_focussed_device_.address_type),
          fmt::arg("device_alias", cur_focussed_device_.alias),
          fmt::arg("device_battery_percentage", cur_focussed_device_.battery_percentage.value_or(0))
          ));
  }

  // Call parent update
  ALabel::update();
}

// NOTE: only for when the org.bluez.Battery1 interface is added/removed after/before a device is connected/disconnected
auto waybar::modules::Bluetooth::onInterfaceAddedOrRemoved(GDBusObjectManager *manager, GDBusObject *object,
    GDBusInterface *interface,
    gpointer user_data) -> void
{
  std::string interface_name = g_dbus_proxy_get_interface_name(G_DBUS_PROXY(interface));
  std::string object_path = g_dbus_proxy_get_object_path(G_DBUS_PROXY(interface));
  if (interface_name == "org.bluez.Battery1") {
    Bluetooth* bt = static_cast<Bluetooth*>(user_data);
    auto device = std::find_if(bt->connected_devices_.begin(), bt->connected_devices_.end(), [object_path](auto d){ return d.path == object_path; });
    if (device != bt->connected_devices_.end()) {
      device->battery_percentage = bt->getDeviceBatteryPercentage(object);
      bt->dp.emit();
    }
  }
}

auto waybar::modules::Bluetooth::onInterfaceProxyPropertiesChanged(GDBusObjectManagerClient *manager,
    GDBusObjectProxy *object_proxy,
    GDBusProxy *interface_proxy,
    GVariant *changed_properties,
    const gchar *const *invalidated_properties,
    gpointer user_data) -> void
{
  std::string interface_name = g_dbus_proxy_get_interface_name(interface_proxy);
  std::string object_path = g_dbus_object_get_object_path(G_DBUS_OBJECT(object_proxy));

  Bluetooth* bt = static_cast<Bluetooth*>(user_data);
  if (interface_name == "org.bluez.Adapter1") {
    if (object_path == bt->cur_adapter_.path) {
      bt->getAdapterProperties(G_DBUS_OBJECT(object_proxy), bt->cur_adapter_);
      bt->dp.emit();
    }
  } else if (interface_name == "org.bluez.Device1" ||
             interface_name == "org.bluez.Battery1") {
    DeviceInfo device;
    bt->getDeviceProperties(G_DBUS_OBJECT(object_proxy), device);
    auto cur_device = std::find_if(bt->connected_devices_.begin(), bt->connected_devices_.end(), [device](auto d){ return d.path == device.path; });
    if (cur_device == bt->connected_devices_.end()) {
      if (device.connected) {
        bt->connected_devices_.push_back(device);
        bt->dp.emit();
      }
    } else {
      if (!device.connected) {
        bt->connected_devices_.erase(cur_device);
      } else {
        *cur_device = device;
      }
      bt->dp.emit();
    }
  }
}

auto waybar::modules::Bluetooth::getDeviceBatteryPercentage(GDBusObject* object) -> std::optional<unsigned char> {
  GDBusProxy* proxy_device_bat = G_DBUS_PROXY(g_dbus_object_get_interface(object, "org.bluez.Battery1"));
  if (proxy_device_bat != NULL) {
    unsigned char battery_percentage = getUcharProperty(proxy_device_bat, "Percentage");
    g_object_unref(proxy_device_bat);

    return battery_percentage;
  }
  return std::nullopt;
}

auto waybar::modules::Bluetooth::getDeviceProperties(GDBusObject* object, DeviceInfo& device_info) -> bool {
  GDBusProxy* proxy_device = G_DBUS_PROXY(g_dbus_object_get_interface(object, "org.bluez.Device1"));

  if (proxy_device != NULL) {
    device_info.path = g_dbus_object_get_object_path(object);
    device_info.paired_adapter = getStringProperty(proxy_device, "Adapter");
    device_info.address = getStringProperty(proxy_device, "Address");
    device_info.address_type = getStringProperty(proxy_device, "AddressType");
    device_info.alias = getStringProperty(proxy_device, "Alias");
    device_info.icon = getOptionalStringProperty(proxy_device, "Icon");
    device_info.paired = getBoolProperty(proxy_device, "Paired");
    device_info.trusted = getBoolProperty(proxy_device, "Trusted");
    device_info.blocked = getBoolProperty(proxy_device, "Blocked");
    device_info.connected = getBoolProperty(proxy_device, "Connected");
    device_info.services_resolved = getBoolProperty(proxy_device, "ServicesResolved");

    g_object_unref(proxy_device);

    device_info.battery_percentage = getDeviceBatteryPercentage(object);

    return true;
  }
  return false;
}

auto waybar::modules::Bluetooth::getAdapterProperties(GDBusObject* object, AdapterInfo& adapter_info) -> bool {
  GDBusProxy* proxy_adapter = G_DBUS_PROXY(g_dbus_object_get_interface(object, "org.bluez.Adapter1"));

  if (proxy_adapter != NULL) {
    adapter_info.path = g_dbus_object_get_object_path(object);
    adapter_info.address = getStringProperty(proxy_adapter, "Address");
    adapter_info.address_type = getStringProperty(proxy_adapter, "AddressType");
    adapter_info.alias = getStringProperty(proxy_adapter, "Alias");
    adapter_info.powered = getBoolProperty(proxy_adapter, "Powered");
    adapter_info.discoverable = getBoolProperty(proxy_adapter, "Discoverable");
    adapter_info.pairable = getBoolProperty(proxy_adapter, "Pairable");
    adapter_info.discovering = getBoolProperty(proxy_adapter, "Discovering");

    g_object_unref(proxy_adapter);

    return true;
  }
  return false;
}

auto waybar::modules::Bluetooth::findCurAdapter(AdapterInfo& adapter_info) -> bool {
  bool found_adapter = false;

  GList* objects = g_dbus_object_manager_get_objects(manager_.get());
  for (GList* l = objects; l != NULL; l = l->next) {
    GDBusObject* object = G_DBUS_OBJECT(l->data);
    if (getAdapterProperties(object, adapter_info) && (!config_["adapter-alias"].isString() || config_["adapter-alias"].asString() == adapter_info.alias)) {
      found_adapter = true;
      break;
    }
  }
  g_list_free_full(objects, g_object_unref);

  return found_adapter;
}

auto waybar::modules::Bluetooth::findConnectedDevices(const std::string& cur_adapter_path, std::vector<DeviceInfo>& connected_devices) -> void {
  GList* objects = g_dbus_object_manager_get_objects(manager_.get());
  for (GList* l = objects; l != NULL; l = l->next)
  {
    GDBusObject* object = G_DBUS_OBJECT(l->data);
    DeviceInfo device;
    if (getDeviceProperties(object, device) && device.connected && device.paired_adapter == cur_adapter_.path) {
      connected_devices.push_back(device);
    }
  }
  g_list_free_full(objects, g_object_unref);
}