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

use crate::{EventController, Gesture, PropagationLimit, PropagationPhase};
use glib::{
    prelude::*,
    signal::{connect_raw, SignalHandlerId},
    translate::*,
};
use std::{boxed::Box as Box_, fmt, mem::transmute};

glib::wrapper! {
    /// [`GestureZoom`][crate::GestureZoom] is a [`Gesture`][crate::Gesture] for 2-finger pinch/zoom gestures.
    ///
    /// Whenever the distance between both tracked sequences changes, the
    /// [`scale-changed`][struct@crate::GestureZoom#scale-changed] signal is emitted to report
    /// the scale factor.
    ///
    /// ## Signals
    ///
    ///
    /// #### `scale-changed`
    ///  Emitted whenever the distance between both tracked sequences changes.
    ///
    ///
    /// <details><summary><h4>Gesture</h4></summary>
    ///
    ///
    /// #### `begin`
    ///  Emitted when the gesture is recognized.
    ///
    /// This means the number of touch sequences matches
    /// [`n-points`][struct@crate::Gesture#n-points].
    ///
    /// Note: These conditions may also happen when an extra touch
    /// (eg. a third touch on a 2-touches gesture) is lifted, in that
    /// situation @sequence won't pertain to the current set of active
    /// touches, so don't rely on this being true.
    ///
    ///
    ///
    ///
    /// #### `cancel`
    ///  Emitted whenever a sequence is cancelled.
    ///
    /// This usually happens on active touches when
    /// [`EventControllerExt::reset()`][crate::prelude::EventControllerExt::reset()] is called on @gesture
    /// (manually, due to grabs...), or the individual @sequence
    /// was claimed by parent widgets' controllers (see
    /// [`GestureExt::set_sequence_state()`][crate::prelude::GestureExt::set_sequence_state()]).
    ///
    /// @gesture must forget everything about @sequence as in
    /// response to this signal.
    ///
    ///
    ///
    ///
    /// #### `end`
    ///  Emitted when @gesture either stopped recognizing the event
    /// sequences as something to be handled, or the number of touch
    /// sequences became higher or lower than [`n-points`][struct@crate::Gesture#n-points].
    ///
    /// Note: @sequence might not pertain to the group of sequences that
    /// were previously triggering recognition on @gesture (ie. a just
    /// pressed touch sequence that exceeds [`n-points`][struct@crate::Gesture#n-points]).
    /// This situation may be detected by checking through
    /// [`GestureExt::handles_sequence()`][crate::prelude::GestureExt::handles_sequence()].
    ///
    ///
    ///
    ///
    /// #### `sequence-state-changed`
    ///  Emitted whenever a sequence state changes.
    ///
    /// See [`GestureExt::set_sequence_state()`][crate::prelude::GestureExt::set_sequence_state()] to know
    /// more about the expectable sequence lifetimes.
    ///
    ///
    ///
    ///
    /// #### `update`
    ///  Emitted whenever an event is handled while the gesture is recognized.
    ///
    /// @sequence is guaranteed to pertain to the set of active touches.
    ///
    ///
    /// </details>
    ///
    /// # Implements
    ///
    /// [`GestureExt`][trait@crate::prelude::GestureExt], [`EventControllerExt`][trait@crate::prelude::EventControllerExt], [`trait@glib::ObjectExt`]
    #[doc(alias = "GtkGestureZoom")]
    pub struct GestureZoom(Object<ffi::GtkGestureZoom, ffi::GtkGestureZoomClass>) @extends Gesture, EventController;

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

impl GestureZoom {
    /// Returns a newly created [`Gesture`][crate::Gesture] that recognizes
    /// pinch/zoom gestures.
    ///
    /// # Returns
    ///
    /// a newly created [`GestureZoom`][crate::GestureZoom]
    #[doc(alias = "gtk_gesture_zoom_new")]
    pub fn new() -> GestureZoom {
        assert_initialized_main_thread!();
        unsafe { Gesture::from_glib_full(ffi::gtk_gesture_zoom_new()).unsafe_cast() }
    }

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

    /// Gets the scale delta.
    ///
    /// If @self is active, this function returns the zooming
    /// difference since the gesture was recognized (hence the
    /// starting point is considered 1:1). If @self is not
    /// active, 1 is returned.
    ///
    /// # Returns
    ///
    /// the scale delta
    #[doc(alias = "gtk_gesture_zoom_get_scale_delta")]
    #[doc(alias = "get_scale_delta")]
    pub fn scale_delta(&self) -> f64 {
        unsafe { ffi::gtk_gesture_zoom_get_scale_delta(self.to_glib_none().0) }
    }

    /// Emitted whenever the distance between both tracked sequences changes.
    /// ## `scale`
    /// Scale delta, taking the initial state as 1:1
    #[doc(alias = "scale-changed")]
    pub fn connect_scale_changed<F: Fn(&Self, f64) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn scale_changed_trampoline<F: Fn(&GestureZoom, f64) + 'static>(
            this: *mut ffi::GtkGestureZoom,
            scale: libc::c_double,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(&from_glib_borrow(this), scale)
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"scale-changed\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    scale_changed_trampoline::<F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }
}

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

// rustdoc-stripper-ignore-next
/// A [builder-pattern] type to construct [`GestureZoom`] objects.
///
/// [builder-pattern]: https://doc.rust-lang.org/1.0.0/style/ownership/builders.html
#[must_use = "The builder must be built to be used"]
pub struct GestureZoomBuilder {
    builder: glib::object::ObjectBuilder<'static, GestureZoom>,
}

impl GestureZoomBuilder {
    fn new() -> Self {
        Self {
            builder: glib::object::Object::builder(),
        }
    }

    /// The number of touch points that trigger
    /// recognition on this gesture.
    pub fn n_points(self, n_points: u32) -> Self {
        Self {
            builder: self.builder.property("n-points", n_points),
        }
    }

    /// The name for this controller, typically used for debugging purposes.
    pub fn name(self, name: impl Into<glib::GString>) -> Self {
        Self {
            builder: self.builder.property("name", name.into()),
        }
    }

    /// The limit for which events this controller will handle.
    pub fn propagation_limit(self, propagation_limit: PropagationLimit) -> Self {
        Self {
            builder: self
                .builder
                .property("propagation-limit", propagation_limit),
        }
    }

    /// The propagation phase at which this controller will handle events.
    pub fn propagation_phase(self, propagation_phase: PropagationPhase) -> Self {
        Self {
            builder: self
                .builder
                .property("propagation-phase", propagation_phase),
        }
    }

    // rustdoc-stripper-ignore-next
    /// Build the [`GestureZoom`].
    #[must_use = "Building the object from the builder is usually expensive and is not expected to have side effects"]
    pub fn build(self) -> GestureZoom {
        self.builder.build()
    }
}

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