// Take a look at the license at the top of the repository in the LICENSE file.

use glib::translate::*;
use graphene::{Point, Rect, Size};
use std::mem;

/// A rectangular region with rounded corners.
///
/// Application code should normalize rectangles using
/// [``normalize()``][`Self::normalize()`]; this function will ensure that
/// the bounds of the rectangle are normalized and ensure that the corner
/// values are positive and the corners do not overlap.
///
/// All functions taking a [`RoundedRect`][crate::RoundedRect] as an argument will internally
/// operate on a normalized copy; all functions returning a [`RoundedRect`][crate::RoundedRect]
/// will always return a normalized one.
///
/// The algorithm used for normalizing corner sizes is described in
/// [the CSS specification](https://drafts.csswg.org/css-backgrounds-3/`border`-radius).
#[derive(Clone, Debug)]
#[doc(alias = "GskRoundedRect")]
pub struct RoundedRect(ffi::GskRoundedRect);

impl RoundedRect {
    #[doc(alias = "gsk_rounded_rect_init")]
    pub fn new(
        bounds: Rect,
        top_left: Size,
        top_right: Size,
        bottom_right: Size,
        bottom_left: Size,
    ) -> Self {
        assert_initialized_main_thread!();
        unsafe {
            let mut rounded_rect = mem::MaybeUninit::uninit();
            ffi::gsk_rounded_rect_init(
                rounded_rect.as_mut_ptr(),
                bounds.to_glib_none().0,
                top_left.to_glib_none().0,
                top_right.to_glib_none().0,
                bottom_right.to_glib_none().0,
                bottom_left.to_glib_none().0,
            );
            Self(rounded_rect.assume_init())
        }
    }

    #[doc(alias = "gsk_rounded_rect_init_from_rect")]
    #[doc(alias = "init_from_rect")]
    pub fn from_rect(bounds: Rect, radius: f32) -> Self {
        assert_initialized_main_thread!();
        unsafe {
            let mut rounded_rect = mem::MaybeUninit::uninit();
            ffi::gsk_rounded_rect_init_from_rect(
                rounded_rect.as_mut_ptr(),
                bounds.to_glib_none().0,
                radius,
            );
            Self(rounded_rect.assume_init())
        }
    }

    /// Initializes the given [`RoundedRect`][crate::RoundedRect] with the given values.
    ///
    /// This function will implicitly normalize the [`RoundedRect`][crate::RoundedRect]
    /// before returning.
    /// ## `bounds`
    /// a `graphene_rect_t` describing the bounds
    /// ## `top_left`
    /// the rounding radius of the top left corner
    /// ## `top_right`
    /// the rounding radius of the top right corner
    /// ## `bottom_right`
    /// the rounding radius of the bottom right corner
    /// ## `bottom_left`
    /// the rounding radius of the bottom left corner
    ///
    /// # Returns
    ///
    /// the initialized rectangle
    #[doc(alias = "gsk_rounded_rect_init")]
    pub fn init(
        &mut self,
        bounds: Rect,
        top_left: Size,
        top_right: Size,
        bottom_right: Size,
        bottom_left: Size,
    ) {
        unsafe {
            ffi::gsk_rounded_rect_init(
                &mut self.0,
                bounds.to_glib_none().0,
                top_left.to_glib_none().0,
                top_right.to_glib_none().0,
                bottom_right.to_glib_none().0,
                bottom_left.to_glib_none().0,
            );
        }
    }

    /// Initializes `self` to the given `bounds` and sets the radius
    /// of all four corners to `radius`.
    /// ## `bounds`
    /// a `graphene_rect_t`
    /// ## `radius`
    /// the border radius
    ///
    /// # Returns
    ///
    /// the initialized rectangle
    #[doc(alias = "gsk_rounded_rect_init_from_rect")]
    pub fn init_from_rect(&mut self, bounds: Rect, radius: f32) {
        unsafe {
            ffi::gsk_rounded_rect_init_from_rect(&mut self.0, bounds.to_glib_none().0, radius);
        }
    }

    /// Normalizes the passed rectangle.
    ///
    /// This function will ensure that the bounds of the rectangle
    /// are normalized and ensure that the corner values are positive
    /// and the corners do not overlap.
    ///
    /// # Returns
    ///
    /// the normalized rectangle
    #[doc(alias = "gsk_rounded_rect_normalize")]
    pub fn normalize(&mut self) {
        unsafe {
            ffi::gsk_rounded_rect_normalize(&mut self.0);
        }
    }

    /// Offsets the bound's origin by `dx` and `dy`.
    ///
    /// The size and corners of the rectangle are unchanged.
    /// ## `dx`
    /// the horizontal offset
    /// ## `dy`
    /// the vertical offset
    ///
    /// # Returns
    ///
    /// the offset rectangle
    #[doc(alias = "gsk_rounded_rect_offset")]
    pub fn offset(&mut self, dx: f32, dy: f32) {
        unsafe {
            ffi::gsk_rounded_rect_offset(&mut self.0, dx, dy);
        }
    }

    /// Shrinks (or grows) the given rectangle by moving the 4 sides
    /// according to the offsets given.
    ///
    /// The corner radii will be changed in a way that tries to keep
    /// the center of the corner circle intact. This emulates CSS behavior.
    ///
    /// This function also works for growing rectangles if you pass
    /// negative values for the `top`, `right`, `bottom` or `left`.
    /// ## `top`
    /// How far to move the top side downwards
    /// ## `right`
    /// How far to move the right side to the left
    /// ## `bottom`
    /// How far to move the bottom side upwards
    /// ## `left`
    /// How far to move the left side to the right
    ///
    /// # Returns
    ///
    /// the resized [`RoundedRect`][crate::RoundedRect]
    #[doc(alias = "gsk_rounded_rect_shrink")]
    pub fn shrink(&mut self, top: f32, right: f32, bottom: f32, left: f32) {
        unsafe {
            ffi::gsk_rounded_rect_shrink(&mut self.0, top, right, bottom, left);
        }
    }

    /// Checks if all corners of `self` are right angles and the
    /// rectangle covers all of its bounds.
    ///
    /// This information can be used to decide if [``ClipNode::new()``][crate::`ClipNode::new()`]
    /// or [``RoundedClipNode::new()``][crate::`RoundedClipNode::new()`] should be called.
    ///
    /// # Returns
    ///
    /// [`true`] if the rectangle is rectilinear
    #[doc(alias = "gsk_rounded_rect_is_rectilinear")]
    pub fn is_rectilinear(&self) -> bool {
        unsafe { from_glib(ffi::gsk_rounded_rect_is_rectilinear(&self.0)) }
    }

    /// Checks if the given `point` is inside the rounded rectangle.
    /// ## `point`
    /// the point to check
    ///
    /// # Returns
    ///
    /// [`true`] if the `point` is inside the rounded rectangle
    #[doc(alias = "gsk_rounded_rect_contains_point")]
    pub fn contains_point(&self, point: Point) -> bool {
        unsafe {
            from_glib(ffi::gsk_rounded_rect_contains_point(
                &self.0,
                point.to_glib_none().0,
            ))
        }
    }

    /// Checks if the given `rect` is contained inside the rounded rectangle.
    /// ## `rect`
    /// the rectangle to check
    ///
    /// # Returns
    ///
    /// [`true`] if the `rect` is fully contained inside the rounded rectangle
    #[doc(alias = "gsk_rounded_rect_contains_rect")]
    pub fn contains_rect(&self, rect: Rect) -> bool {
        unsafe {
            from_glib(ffi::gsk_rounded_rect_contains_rect(
                &self.0,
                rect.to_glib_none().0,
            ))
        }
    }

    /// Checks if part of the given `rect` is contained inside the rounded rectangle.
    /// ## `rect`
    /// the rectangle to check
    ///
    /// # Returns
    ///
    /// [`true`] if the `rect` intersects with the rounded rectangle
    #[doc(alias = "gsk_rounded_rect_intersects_rect")]
    pub fn intersects_rect(&self, rect: Rect) -> bool {
        unsafe {
            from_glib(ffi::gsk_rounded_rect_intersects_rect(
                &self.0,
                rect.to_glib_none().0,
            ))
        }
    }
}

#[doc(hidden)]
impl FromGlibPtrNone<*const ffi::GskRoundedRect> for RoundedRect {
    unsafe fn from_glib_none(ptr: *const ffi::GskRoundedRect) -> Self {
        Self(*ptr)
    }
}

#[doc(hidden)]
impl<'a> ToGlibPtr<'a, *const ffi::GskRoundedRect> for RoundedRect {
    type Storage = &'a Self;

    fn to_glib_none(&'a self) -> Stash<*const ffi::GskRoundedRect, Self> {
        Stash(&self.0, self)
    }
}