// 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::Ordering;
use crate::SorterChange;
use crate::SorterOrder;
use glib::object::Cast;
use glib::object::IsA;
use glib::signal::connect_raw;
use glib::signal::SignalHandlerId;
use glib::translate::*;
use std::boxed::Box as Box_;
use std::fmt;
use std::mem::transmute;

glib::wrapper! {
    /// [`Sorter`][crate::Sorter] is an object to describe sorting criteria.
    ///
    /// Its primary user is [`SortListModel`][crate::SortListModel]
    ///
    /// The model will use a sorter to determine the order in which
    /// its items should appear by calling `Gtk::`Sorter::compare()``
    /// for pairs of items.
    ///
    /// Sorters may change their sorting behavior through their lifetime.
    /// In that case, they will emit the `signal::Sorter::changed` signal
    /// to notify that the sort order is no longer valid and should be updated
    /// by calling `gtk_sorter_compare()` again.
    ///
    /// GTK provides various pre-made sorter implementations for common sorting
    /// operations. [`ColumnView`][crate::ColumnView] has built-in support for sorting lists
    /// via the `property::ColumnViewColumn::sorter` property, where the user can
    /// change the sorting by clicking on list headers.
    ///
    /// Of course, in particular for large lists, it is also possible to subclass
    /// [`Sorter`][crate::Sorter] and provide one's own sorter.
    ///
    /// # Implements
    ///
    /// [`SorterExt`][trait@crate::prelude::SorterExt], [`trait@glib::ObjectExt`]
    #[doc(alias = "GtkSorter")]
    pub struct Sorter(Object<ffi::GtkSorter, ffi::GtkSorterClass>);

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

pub const NONE_SORTER: Option<&Sorter> = None;

/// Trait containing all [`struct@Sorter`] methods.
///
/// # Implementors
///
/// [`CustomSorter`][struct@crate::CustomSorter], [`MultiSorter`][struct@crate::MultiSorter], [`NumericSorter`][struct@crate::NumericSorter], [`Sorter`][struct@crate::Sorter], [`StringSorter`][struct@crate::StringSorter], [`TreeListRowSorter`][struct@crate::TreeListRowSorter]
pub trait SorterExt: 'static {
    /// Notifies all users of the sorter that it has changed.
    ///
    /// This emits the `signal::Sorter::changed` signal. Users
    /// of the sorter should then update the sort order via
    /// `Gtk::`Sorter::compare()``.
    ///
    /// Depending on the `change` parameter, it may be possible to
    /// update the sort order without a full resorting. Refer to
    /// the [`SorterChange`][crate::SorterChange] documentation for details.
    ///
    /// This function is intended for implementors of [`Sorter`][crate::Sorter]
    /// subclasses and should not be called from other functions.
    /// ## `change`
    /// How the sorter changed
    #[doc(alias = "gtk_sorter_changed")]
    fn changed(&self, change: SorterChange);

    /// Compares two given items according to the sort order implemented
    /// by the sorter.
    ///
    /// Sorters implement a partial order:
    ///
    /// * It is reflexive, ie a = a
    /// * It is antisymmetric, ie if a < b and b < a, then a = b
    /// * It is transitive, ie given any 3 items with a ≤ b and b ≤ c,
    ///  then a ≤ c
    ///
    /// The sorter may signal it conforms to additional constraints
    /// via the return value of [``order()``][`Self::order()`].
    /// ## `item1`
    /// first item to compare
    /// ## `item2`
    /// second item to compare
    ///
    /// # Returns
    ///
    /// [`Ordering::Equal`][crate::Ordering::Equal] if `item1` == `item2`,
    ///  [`Ordering::Smaller`][crate::Ordering::Smaller] if `item1` < `item2`,
    ///  [`Ordering::Larger`][crate::Ordering::Larger] if `item1` > `item2`
    #[doc(alias = "gtk_sorter_compare")]
    fn compare<P: IsA<glib::Object>, Q: IsA<glib::Object>>(&self, item1: &P, item2: &Q)
        -> Ordering;

    /// Gets the order that `self` conforms to.
    ///
    /// See [`SorterOrder`][crate::SorterOrder] for details
    /// of the possible return values.
    ///
    /// This function is intended to allow optimizations.
    ///
    /// # Returns
    ///
    /// The order
    #[doc(alias = "gtk_sorter_get_order")]
    #[doc(alias = "get_order")]
    fn order(&self) -> SorterOrder;

    /// Emitted whenever the sorter changed.
    ///
    /// Users of the sorter should then update the sort order
    /// again via `gtk_sorter_compare()`.
    ///
    /// [`SortListModel`][crate::SortListModel] handles this signal automatically.
    ///
    /// Depending on the `change` parameter, it may be possible to update
    /// the sort order without a full resorting. Refer to the
    /// [`SorterChange`][crate::SorterChange] documentation for details.
    /// ## `change`
    /// how the sorter changed
    #[doc(alias = "changed")]
    fn connect_changed<F: Fn(&Self, SorterChange) + 'static>(&self, f: F) -> SignalHandlerId;
}

impl<O: IsA<Sorter>> SorterExt for O {
    fn changed(&self, change: SorterChange) {
        unsafe {
            ffi::gtk_sorter_changed(self.as_ref().to_glib_none().0, change.into_glib());
        }
    }

    fn compare<P: IsA<glib::Object>, Q: IsA<glib::Object>>(
        &self,
        item1: &P,
        item2: &Q,
    ) -> Ordering {
        unsafe {
            from_glib(ffi::gtk_sorter_compare(
                self.as_ref().to_glib_none().0,
                item1.as_ref().to_glib_none().0,
                item2.as_ref().to_glib_none().0,
            ))
        }
    }

    fn order(&self) -> SorterOrder {
        unsafe { from_glib(ffi::gtk_sorter_get_order(self.as_ref().to_glib_none().0)) }
    }

    fn connect_changed<F: Fn(&Self, SorterChange) + 'static>(&self, f: F) -> SignalHandlerId {
        unsafe extern "C" fn changed_trampoline<
            P: IsA<Sorter>,
            F: Fn(&P, SorterChange) + 'static,
        >(
            this: *mut ffi::GtkSorter,
            change: ffi::GtkSorterChange,
            f: glib::ffi::gpointer,
        ) {
            let f: &F = &*(f as *const F);
            f(
                Sorter::from_glib_borrow(this).unsafe_cast_ref(),
                from_glib(change),
            )
        }
        unsafe {
            let f: Box_<F> = Box_::new(f);
            connect_raw(
                self.as_ptr() as *mut _,
                b"changed\0".as_ptr() as *const _,
                Some(transmute::<_, unsafe extern "C" fn()>(
                    changed_trampoline::<Self, F> as *const (),
                )),
                Box_::into_raw(f),
            )
        }
    }
}

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