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// This file was generated by gir (https://github.com/gtk-rs/gir)
// from gir-files (https://github.com/gtk-rs/gir-files.git)
// DO NOT EDIT

use crate::EventController;
use crate::Gesture;
use crate::GestureSingle;
use crate::PropagationLimit;
use crate::PropagationPhase;
use glib::object::Cast;
use glib::object::IsA;
use glib::object::ObjectType as ObjectType_;
use glib::signal::connect_raw;
use glib::signal::SignalHandlerId;
use glib::translate::*;
use glib::StaticType;
use glib::ToValue;
use std::boxed::Box as Box_;
use std::fmt;
use std::mem::transmute;

glib::wrapper! {
    /// [`DragSource`][crate::DragSource] is an event controller to initiate Drag-And-Drop operations.
    ///
    /// [`DragSource`][crate::DragSource] can be set up with the necessary
    /// ingredients for a DND operation ahead of time. This includes
    /// the source for the data that is being transferred, in the form
    /// of a [`gdk::ContentProvider`][crate::gdk::ContentProvider], the desired action, and the icon to
    /// use during the drag operation. After setting it up, the drag
    /// source must be added to a widget as an event controller, using
    /// [``WidgetExt::add_controller()``][crate::prelude::`WidgetExt::add_controller()`].
    ///
    /// **⚠️ The following code is in c ⚠️**
    ///
    /// ```c
    /// static void
    /// my_widget_init (MyWidget *self)
    /// {
    ///   GtkDragSource *drag_source = gtk_drag_source_new ();
    ///
    ///   g_signal_connect (drag_source, "prepare", G_CALLBACK (on_drag_prepare), self);
    ///   g_signal_connect (drag_source, "drag-begin", G_CALLBACK (on_drag_begin), self);
    ///
    ///   gtk_widget_add_controller (GTK_WIDGET (self), GTK_EVENT_CONTROLLER (drag_source));
    /// }
    /// ```
    ///
    /// Setting up the content provider and icon ahead of time only makes
    /// sense when the data does not change. More commonly, you will want
    /// to set them up just in time. To do so, [`DragSource`][crate::DragSource] has
    /// `signal::DragSource::prepare` and `signal::DragSource::drag-begin`
    /// signals.
    ///
    /// The ::prepare signal is emitted before a drag is started, and
    /// can be used to set the content provider and actions that the
    /// drag should be started with.
    ///
    /// **⚠️ The following code is in c ⚠️**
    ///
    /// ```c
    /// static GdkContentProvider *
    /// on_drag_prepare (GtkDragSource *source,
    ///                  double         x,
    ///                  double         y,
    ///                  MyWidget      *self)
    /// {
    ///   // This widget supports two types of content: GFile objects
    ///   // and GdkPixbuf objects; GTK will handle the serialization
    ///   // of these types automatically
    ///   GFile *file = my_widget_get_file (self);
    ///   GdkPixbuf *pixbuf = my_widget_get_pixbuf (self);
    ///
    ///   return gdk_content_provider_new_union ((GdkContentProvider *[2]) {
    ///       gdk_content_provider_new_typed (G_TYPE_FILE, file),
    ///       gdk_content_provider_new_typed (GDK_TYPE_PIXBUF, pixbuf),
    ///     }, 2);
    /// }
    /// ```
    ///
    /// The ::drag-begin signal is emitted after the [`gdk::Drag`][crate::gdk::Drag] object has
    /// been created, and can be used to set up the drag icon.
    ///
    /// **⚠️ The following code is in c ⚠️**
    ///
    /// ```c
    /// static void
    /// on_drag_begin (GtkDragSource *source,
    ///                GtkDrag       *drag,
    ///                MyWidget      *self)
    /// {
    ///   // Set the widget as the drag icon
    ///   GdkPaintable *paintable = gtk_widget_paintable_new (GTK_WIDGET (self));
    ///   gtk_drag_source_set_icon (source, paintable, 0, 0);
    ///   g_object_unref (paintable);
    /// }
    /// ```
    ///
    /// During the DND operation, [`DragSource`][crate::DragSource] emits signals that
    /// can be used to obtain updates about the status of the operation,
    /// but it is not normally necessary to connect to any signals,
    /// except for one case: when the supported actions include
    /// [`gdk::DragAction::MOVE`][crate::gdk::DragAction::MOVE], you need to listen for the
    /// `signal::DragSource::drag-end` signal and delete the
    /// data after it has been transferred.
    ///
    /// # Implements
    ///
    /// [`GestureSingleExt`][trait@crate::prelude::GestureSingleExt], [`GestureExt`][trait@crate::prelude::GestureExt], [`EventControllerExt`][trait@crate::prelude::EventControllerExt], [`trait@glib::ObjectExt`]
    #[doc(alias = "GtkDragSource")]
    pub struct DragSource(Object<ffi::GtkDragSource, ffi::GtkDragSourceClass>) @extends GestureSingle, Gesture, EventController;

    match fn {
        type_ => || ffi::gtk_drag_source_get_type(),
    }
}

impl DragSource {
    /// Creates a new [`DragSource`][crate::DragSource] object.
    ///
    /// # Returns
    ///
    /// the new [`DragSource`][crate::DragSource]
    #[doc(alias = "gtk_drag_source_new")]
    pub fn new() -> DragSource {
        assert_initialized_main_thread!();
        unsafe { from_glib_full(ffi::gtk_drag_source_new()) }
    }

    // rustdoc-stripper-ignore-next
    /// Creates a new builder-pattern struct instance to construct [`DragSource`] objects.
    ///
    /// This method returns an instance of [`DragSourceBuilder`] which can be used to create [`DragSource`] objects.
    pub fn builder() -> DragSourceBuilder {
        DragSourceBuilder::default()
    }

    /// Cancels a currently ongoing drag operation.
    #[doc(alias = "gtk_drag_source_drag_cancel")]
    pub fn drag_cancel(&self) {
        unsafe {
            ffi::gtk_drag_source_drag_cancel(self.to_glib_none().0);
        }
    }

    /// Gets the actions that are currently set on the [`DragSource`][crate::DragSource].
    ///
    /// # Returns
    ///
    /// the actions set on `self`
    #[doc(alias = "gtk_drag_source_get_actions")]
    #[doc(alias = "get_actions")]
    pub fn actions(&self) -> gdk::DragAction {
        unsafe { from_glib(ffi::gtk_drag_source_get_actions(self.to_glib_none().0)) }
    }

    /// Gets the current content provider of a [`DragSource`][crate::DragSource].
    ///
    /// # Returns
    ///
    /// the [`gdk::ContentProvider`][crate::gdk::ContentProvider] of `self`
    #[doc(alias = "gtk_drag_source_get_content")]
    #[doc(alias = "get_content")]
    pub fn content(&self) -> Option<gdk::ContentProvider> {
        unsafe { from_glib_none(ffi::gtk_drag_source_get_content(self.to_glib_none().0)) }
    }

    /// Returns the underlying [`gdk::Drag`][crate::gdk::Drag] object for an ongoing drag.
    ///
    /// # Returns
    ///
    /// the [`gdk::Drag`][crate::gdk::Drag] of the current
    ///  drag operation
    #[doc(alias = "gtk_drag_source_get_drag")]
    #[doc(alias = "get_drag")]
    pub fn drag(&self) -> Option<gdk::Drag> {
        unsafe { from_glib_none(ffi::gtk_drag_source_get_drag(self.to_glib_none().0)) }
    }

    /// Sets the actions on the [`DragSource`][crate::DragSource].
    ///
    /// During a DND operation, the actions are offered to potential
    /// drop targets. If `actions` include [`gdk::DragAction::MOVE`][crate::gdk::DragAction::MOVE], you need
    /// to listen to the `signal::DragSource::drag-end` signal and
    /// handle `delete_data` being [`true`].
    ///
    /// This function can be called before a drag is started,
    /// or in a handler for the `signal::DragSource::prepare` signal.
    /// ## `actions`
    /// the actions to offer
    #[doc(alias = "gtk_drag_source_set_actions")]
    pub fn set_actions(&self, actions: gdk::DragAction) {
        unsafe {
            ffi::gtk_drag_source_set_actions(self.to_glib_none().0, actions.into_glib());
        }
    }

    /// Sets a content provider on a [`DragSource`][crate::DragSource].
    ///
    /// When the data is requested in the cause of a DND operation,
    /// it will be obtained from the content provider.
    ///
    /// This function can be called before a drag is started,
    /// or in a handler for the `signal::DragSource::prepare` signal.
    ///
    /// You may consider setting the content provider back to
    /// [`None`] in a `signal::DragSource::drag-end` signal handler.
    /// ## `content`
    /// a [`gdk::ContentProvider`][crate::gdk::ContentProvider]
    #[doc(alias = "gtk_drag_source_set_content")]
    pub fn set_content<P: IsA<gdk::ContentProvider>>(&self, content: Option<&P>) {
        unsafe {
            ffi::gtk_drag_source_set_content(
                self.to_glib_none().0,
                content.map(|p| p.as_ref()).to_glib_none().0,
            );
        }
    }

    /// Sets a paintable to use as icon during DND operations.
    ///
    /// The hotspot coordinates determine the point on the icon
    /// that gets aligned with the hotspot of the cursor.
    ///
    /// If `paintable` is [`None`], a default icon is used.
    ///
    /// This function can be called before a drag is started, or in
    /// a `signal::DragSource::prepare` or
    /// `signal::DragSource::drag-begin` signal handler.
    /// ## `paintable`
    /// the [`gdk::Paintable`][crate::gdk::Paintable] to use as icon
    /// ## `hot_x`
    /// the hotspot X coordinate on the icon
    /// ## `hot_y`
    /// the hotspot Y coordinate on the icon
    #[doc(alias = "gtk_drag_source_set_icon")]
    pub fn set_icon<P: IsA<gdk::Paintable>>(&self, paintable: Option<&P>, hot_x: i32, hot_y: i32) {
        unsafe {
            ffi::gtk_drag_source_set_icon(
                self.to_glib_none().0,
                paintable.map(|p| p.as_ref()).to_glib_none().0,
                hot_x,
                hot_y,
            );
        }
    }

    /// Emitted on the drag source when a drag is started.
    ///
    /// It can be used to e.g. set a custom drag icon with
    /// [``set_icon()``][`Self::set_icon()`].
    /// ## `drag`
    /// the [`gdk::Drag`][crate::gdk::Drag] object
    #[doc(alias = "drag-begin")]
    pub fn connect_drag_begin<F: Fn(&Self, &gdk::Drag) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn drag_begin_trampoline<F: Fn(&DragSource, &gdk::Drag) + 'static>(
            this: *mut ffi::GtkDragSource,
            drag: *mut gdk::ffi::GdkDrag,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(&from_glib_borrow(this), &from_glib_borrow(drag))
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"drag-begin\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    drag_begin_trampoline::<F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    /// Emitted on the drag source when a drag has failed.
    ///
    /// The signal handler may handle a failed drag operation based on
    /// the type of error. It should return [`true`] if the failure has been handled
    /// and the default "drag operation failed" animation should not be shown.
    /// ## `drag`
    /// the [`gdk::Drag`][crate::gdk::Drag] object
    /// ## `reason`
    /// information on why the drag failed
    ///
    /// # Returns
    ///
    /// [`true`] if the failed drag operation has been already handled
    #[doc(alias = "drag-cancel")]
    pub fn connect_drag_cancel<
        F: Fn(&Self, &gdk::Drag, gdk::DragCancelReason) -> bool + 'static,
    >(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn drag_cancel_trampoline<
            F: Fn(&DragSource, &gdk::Drag, gdk::DragCancelReason) -> bool + 'static,
        >(
            this: *mut ffi::GtkDragSource,
            drag: *mut gdk::ffi::GdkDrag,
            reason: gdk::ffi::GdkDragCancelReason,
            f: glib::ffi::gpointer,
        ) -> glib::ffi::gboolean {
            let f: &F = &*(f as *const F);
            f(
                &from_glib_borrow(this),
                &from_glib_borrow(drag),
                from_glib(reason),
            )
            .into_glib()
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"drag-cancel\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    drag_cancel_trampoline::<F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    /// Emitted on the drag source when a drag is finished.
    ///
    /// A typical reason to connect to this signal is to undo
    /// things done in `signal::DragSource::prepare` or
    /// `signal::DragSource::drag-begin` handlers.
    /// ## `drag`
    /// the [`gdk::Drag`][crate::gdk::Drag] object
    /// ## `delete_data`
    /// [`true`] if the drag was performing [`gdk::DragAction::MOVE`][crate::gdk::DragAction::MOVE],
    ///  and the data should be deleted
    #[doc(alias = "drag-end")]
    pub fn connect_drag_end<F: Fn(&Self, &gdk::Drag, bool) + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn drag_end_trampoline<F: Fn(&DragSource, &gdk::Drag, bool) + 'static>(
            this: *mut ffi::GtkDragSource,
            drag: *mut gdk::ffi::GdkDrag,
            delete_data: glib::ffi::gboolean,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(
                &from_glib_borrow(this),
                &from_glib_borrow(drag),
                from_glib(delete_data),
            )
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"drag-end\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    drag_end_trampoline::<F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    /// Emitted when a drag is about to be initiated.
    ///
    /// It returns the [`gdk::ContentProvider`][crate::gdk::ContentProvider] to use for the drag that is about
    /// to start. The default handler for this signal returns the value of
    /// the `property::DragSource::content` property, so if you set up that
    /// property ahead of time, you don't need to connect to this signal.
    /// ## `x`
    /// the X coordinate of the drag starting point
    /// ## `y`
    /// the Y coordinate fo the drag starting point
    ///
    /// # Returns
    ///
    /// a [`gdk::ContentProvider`][crate::gdk::ContentProvider]
    #[doc(alias = "prepare")]
    pub fn connect_prepare<F: Fn(&Self, f64, f64) -> Option<gdk::ContentProvider> + 'static>(
        &self,
        f: F,
    ) -> SignalHandlerId {
        unsafe extern "C" fn prepare_trampoline<
            F: Fn(&DragSource, f64, f64) -> Option<gdk::ContentProvider> + 'static,
        >(
            this: *mut ffi::GtkDragSource,
            x: libc::c_double,
            y: libc::c_double,
            f: glib::ffi::gpointer,
        ) -> *mut gdk::ffi::GdkContentProvider {
            let f: &F = &*(f as *const F);
            f(&from_glib_borrow(this), x, y).to_glib_full()
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"prepare\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    prepare_trampoline::<F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[doc(alias = "actions")]
    pub fn connect_actions_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_actions_trampoline<F: Fn(&DragSource) + 'static>(
            this: *mut ffi::GtkDragSource,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(&from_glib_borrow(this))
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::actions\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_actions_trampoline::<F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }

    #[doc(alias = "content")]
    pub fn connect_content_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn notify_content_trampoline<F: Fn(&DragSource) + 'static>(
            this: *mut ffi::GtkDragSource,
            _param_spec: glib::ffi::gpointer,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(&from_glib_borrow(this))
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"notify::content\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    notify_content_trampoline::<F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }
}

impl Default for DragSource {
    fn default() -> Self {
        Self::new()
    }
}

#[derive(Clone, Default)]
// rustdoc-stripper-ignore-next
/// A [builder-pattern] type to construct [`DragSource`] objects.
///
/// [builder-pattern]: https://doc.rust-lang.org/1.0.0/style/ownership/builders.html
pub struct DragSourceBuilder {
    actions: Option<gdk::DragAction>,
    content: Option<gdk::ContentProvider>,
    button: Option<u32>,
    exclusive: Option<bool>,
    touch_only: Option<bool>,
    n_points: Option<u32>,
    name: Option<String>,
    propagation_limit: Option<PropagationLimit>,
    propagation_phase: Option<PropagationPhase>,
}

impl DragSourceBuilder {
    // rustdoc-stripper-ignore-next
    /// Create a new [`DragSourceBuilder`].
    pub fn new() -> Self {
        Self::default()
    }

    // rustdoc-stripper-ignore-next
    /// Build the [`DragSource`].
    pub fn build(self) -> DragSource {
        let mut properties: Vec<(&str, &dyn ToValue)> = vec![];
        if let Some(ref actions) = self.actions {
            properties.push(("actions", actions));
        }
        if let Some(ref content) = self.content {
            properties.push(("content", content));
        }
        if let Some(ref button) = self.button {
            properties.push(("button", button));
        }
        if let Some(ref exclusive) = self.exclusive {
            properties.push(("exclusive", exclusive));
        }
        if let Some(ref touch_only) = self.touch_only {
            properties.push(("touch-only", touch_only));
        }
        if let Some(ref n_points) = self.n_points {
            properties.push(("n-points", n_points));
        }
        if let Some(ref name) = self.name {
            properties.push(("name", name));
        }
        if let Some(ref propagation_limit) = self.propagation_limit {
            properties.push(("propagation-limit", propagation_limit));
        }
        if let Some(ref propagation_phase) = self.propagation_phase {
            properties.push(("propagation-phase", propagation_phase));
        }
        glib::Object::new::<DragSource>(&properties)
            .expect("Failed to create an instance of DragSource")
    }

    /// The actions that are supported by drag operations from the source.
    ///
    /// Note that you must handle the `signal::DragSource::drag-end` signal
    /// if the actions include [`gdk::DragAction::MOVE`][crate::gdk::DragAction::MOVE].
    pub fn actions(mut self, actions: gdk::DragAction) -> Self {
        self.actions = Some(actions);
        self
    }

    /// The data that is offered by drag operations from this source.
    pub fn content<P: IsA<gdk::ContentProvider>>(mut self, content: &P) -> Self {
        self.content = Some(content.clone().upcast());
        self
    }

    /// Mouse button number to listen to, or 0 to listen for any button.
    pub fn button(mut self, button: u32) -> Self {
        self.button = Some(button);
        self
    }

    /// Whether the gesture is exclusive.
    ///
    /// Exclusive gestures only listen to pointer and pointer emulated events.
    pub fn exclusive(mut self, exclusive: bool) -> Self {
        self.exclusive = Some(exclusive);
        self
    }

    /// Whether the gesture handles only touch events.
    pub fn touch_only(mut self, touch_only: bool) -> Self {
        self.touch_only = Some(touch_only);
        self
    }

    /// The number of touch points that trigger
    /// recognition on this gesture.
    pub fn n_points(mut self, n_points: u32) -> Self {
        self.n_points = Some(n_points);
        self
    }

    /// The name for this controller, typically used for debugging purposes.
    pub fn name(mut self, name: &str) -> Self {
        self.name = Some(name.to_string());
        self
    }

    /// The limit for which events this controller will handle.
    pub fn propagation_limit(mut self, propagation_limit: PropagationLimit) -> Self {
        self.propagation_limit = Some(propagation_limit);
        self
    }

    /// The propagation phase at which this controller will handle events.
    pub fn propagation_phase(mut self, propagation_phase: PropagationPhase) -> Self {
        self.propagation_phase = Some(propagation_phase);
        self
    }
}

impl fmt::Display for DragSource {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.write_str("DragSource")
    }
}