wip: final simplify

src/space/xywh.rs

@@ -1,4 +1,76 @@
 use super::*;
+use Origin::*;
+use Split::*;
+
+pub trait Xy<N: Coord> {
+    fn x (&self) -> N;
+    fn y (&self) -> N;
+}
+
+pub trait Wh<N: Coord>: Wide<N> + Tall<N> {
+    fn wh (&self) -> [N;2];
+}
+
+pub trait Xywh<N: Coord>: Xy<N> + Wh<N> {
+    fn xywh (&self) -> XYWH<N> {
+        XYWH(self.x(), self.y(), self.w(), self.h())
+    }
+}
+
+pub trait Lrtb<N: Coord> {
+    // FIXME: factor origin
+    fn lrtb (&self) -> [N;4] {
+        [self.x(), self.y(), self.x()+self.w(), self.y()+self.h()]
+    }
+}
+
+pub trait Wide<N: Coord> {
+    fn w (&self) -> N { N::zero() }
+    fn w_min (&self) -> N { self.w() }
+    fn w_max (&self) -> N { self.w() }
+    fn iter_x (&self) -> impl Iterator<Item = N> where Self: HasOrigin {
+        self.x_west()..self.x_east()
+    }
+    fn x_west (&self) -> N where Self: HasOrigin {
+        let w = self.w();
+        let a = self.origin();
+        let d = match a { NW|W|SW => 0.into(), N|X|C|Y|S => w/2.into(), NE|E|SE => w };
+        self.x().minus(d)
+    }
+    fn x_east (&self) -> N where Self: HasOrigin {
+        let w = self.w();
+        let a = self.origin();
+        let d = match a { NW|W|SW => w, N|X|C|Y|S => w/2.into(), NE|E|SE => 0.into() };
+        self.x().plus(d)
+    }
+    fn x_center (&self) -> N where Self: HasOrigin {
+        todo!()
+    }
+}
+
+pub trait Tall<N: Coord> {
+    fn h (&self) -> N { N::zero() }
+    fn h_min (&self) -> N { self.h() }
+    fn h_max (&self) -> N { self.h() }
+    fn iter_y (&self) -> impl Iterator<Item = N> where Self: HasOrigin {
+        self.y_north()..self.y_south()
+    }
+    fn y_north (&self) -> N where Self: HasOrigin {
+        let a = self.origin();
+        let h = self.h();
+        let d = match a { NW|N|NE => 0.into(), W|X|C|Y|E => h/2.into(), SW|S|SE => h };
+        self.y().minus(d)
+    }
+    fn y_south (&self) -> N where Self: HasOrigin  {
+        let a = self.origin();
+        let h = self.h();
+        let d = match a { NW|N|NE => h, W|X|C|Y|E => h/2.into(), SW|S|SE => 0.into() };
+        self.y().plus(d)
+    }
+    fn y_center (&self) -> N where Self: HasOrigin {
+        todo!()
+    }
+}
 
 /// Point with size.
 ///
@@ -13,21 +85,14 @@ use super::*;
 #[cfg_attr(test, derive(Arbitrary))] #[derive(Copy, Clone, Debug, Default, PartialEq)]
 pub struct XYWH<N: Coord>(pub N, pub N, pub N, pub N);
 
-impl From<&ratatui::prelude::Rect> for XYWH<u16> {
-    fn from (rect: &ratatui::prelude::Rect) -> Self {
-        Self(rect.x, rect.y, rect.width, rect.height)
-    }
-}
-
-impl<N: Coord> X<N> for XYWH<N> {
+impl<N: Coord> Xy<N> for XYWH<N> {
     fn x (&self) -> N { self.0 }
-    fn w (&self) -> N { self.2 }
+    fn y (&self) -> N { self.1 }
 }
 
-impl<N: Coord> Y<N> for XYWH<N> {
-    fn y (&self) -> N { self.0 }
-    fn h (&self) -> N { self.2 }
-}
+impl<N: Coord> Wide<N> for XYWH<N> { fn w (&self) -> N { self.2 } }
+
+impl<N: Coord> Tall<N> for XYWH<N> { fn h (&self) -> N { self.3 } }
 
 impl<N: Coord> XYWH<N> {
 
@@ -67,7 +132,6 @@ impl<N: Coord> XYWH<N> {
     }
 
     pub fn split_half (&self, direction: &Split) -> (Self, Self) {
-        use Split::*;
         let XYWH(x, y, w, h) = self.xywh();
         match direction {
             South => (XYWH(x, y, w, h - h / 2.into()), XYWH(x, y + h / 2.into(), w, h / 2.into())),
@@ -79,3 +143,144 @@ impl<N: Coord> XYWH<N> {
     }
 
 }
+
+impl From<&ratatui::prelude::Rect> for XYWH<u16> {
+    fn from (rect: &ratatui::prelude::Rect) -> Self {
+        Self(rect.x, rect.y, rect.width, rect.height)
+    }
+}
+
+impl<N: Coord, T: Wide<N> + Tall<N>> Wh<N> for T {
+    fn wh (&self) -> [N;2] {
+        [self.w(), self.h()]
+    }
+}
+
+impl<N: Coord, T: Xy<N> + Wh<N>> Xywh<N> for T {}
+
+/// Shrink drawing area symmetrically.
+///
+/// ```
+/// let padded = tengri::wh_pad("Hello");
+/// ```
+pub const fn wh_pad <T: Screen> (w: T::Unit, h: T::Unit, it: impl Draw<T>)
+    -> impl Draw<T>
+{
+    thunk(move|to: &mut T|it.draw(todo!()))
+}
+
+/// Only draw content if area is above a certain size.
+///
+/// ```
+/// let min = tengri::wh_min(3, 5, "Hello"); // 5x5
+/// ```
+pub const fn wh_min <T: Screen> (w: Option<T::Unit>, h: Option<T::Unit>, it: impl Draw<T>)
+    -> impl Draw<T>
+{
+    thunk(move|to: &mut T|it.draw(todo!()))
+}
+
+/// Set the maximum width and/or height of the content.
+///
+/// ```
+/// let max = tengri::wh_max(Some(3), Some(5), "Hello");
+/// ```
+pub const fn wh_max <T: Screen> (w: Option<T::Unit>, h: Option<T::Unit>, it: impl Draw<T>)
+    -> impl Draw<T>
+{
+    thunk(move|_to: &mut T|it.draw(todo!()))
+}
+
+/// Set the maximum width and/or height of the content.
+///
+/// ```
+/// let exact = tengri::wh_exact(Some(3), Some(5), "Hello");
+/// ```
+pub const fn wh_exact <T: Screen> (w: Option<T::Unit>, h: Option<T::Unit>, it: impl Draw<T>)
+    -> impl Draw<T>
+{
+    thunk(move|_to: &mut T|it.draw(todo!()))
+}
+
+/// Limit size of drawing area
+/// ```
+/// let clipped = tengri::wh_clip(Some(3), Some(5), "Hello");
+/// ```
+pub const fn wh_clip <T: Screen> (
+    w: Option<T::Unit>, h: Option<T::Unit>, it: impl Draw<T>
+) -> impl Draw<T> {
+    thunk(move|_to: &mut T|it.draw(todo!()))
+}
+
+pub const fn wh_full <T: Screen> (a: impl Draw<T>) -> impl Draw<T> {
+    todo!();
+    a
+}
+
+pub const fn w_full <T: Screen> (a: impl Draw<T>) -> impl Draw<T> {
+    todo!();
+    a
+}
+
+pub const fn h_full <T: Screen> (a: impl Draw<T>) -> impl Draw<T> {
+    todo!();
+    a
+}
+
+pub const fn h_max <T: Screen> (h: Option<T::Unit>, a: impl Draw<T>) -> impl Draw<T> {
+    wh_max(None, h, a)
+}
+pub const fn h_min <T: Screen> (h: Option<T::Unit>, a: impl Draw<T>) -> impl Draw<T> {
+    wh_min(None, h, a)
+}
+pub const fn h_exact <T: Screen> (h: T::Unit, c: impl Draw<T>) -> impl Draw<T> {
+    wh_exact(None, Some(h), c)
+}
+pub const fn w_max <T: Screen> (w: Option<T::Unit>, a: impl Draw<T>) -> impl Draw<T> {
+    wh_max(w, None, a)
+}
+pub const fn w_min <T: Screen> (w: Option<T::Unit>, a: impl Draw<T>) -> impl Draw<T> {
+    wh_min(w, None, a)
+}
+pub const fn w_exact <T: Screen> (w: T::Unit, c: impl Draw<T>) -> impl Draw<T> {
+    wh_exact(Some(w), None, c)
+}
+/// Shrink drawing area symmetrically.
+///
+/// ```
+/// let padded = tengri::space::w_pad(3, "Hello");
+/// ```
+pub const fn w_pad <T: Screen> (x: T::Unit, draw: impl Draw<T>) -> impl Draw<T> {
+    thunk(move|to: &mut T|draw.draw(todo!()))
+}
+/// Shrink drawing area symmetrically.
+///
+/// ```
+/// let padded = tengri::space::w_pad(3, "Hello");
+/// ```
+pub const fn h_pad <T: Screen> (x: T::Unit, draw: impl Draw<T>) -> impl Draw<T> {
+    thunk(move|to: &mut T|draw.draw(todo!()))
+}
+
+pub const fn xy_push <T: Screen> (x: T::Unit, y: T::Unit, a: impl Draw<T>) -> impl Draw<T> {
+    a
+}
+
+pub const fn xy_pull <T: Screen> (x: T::Unit, y: T::Unit, a: impl Draw<T>) -> impl Draw<T> {
+    a
+}
+
+pub const fn x_push <T: Screen> (x: T::Unit, a: impl Draw<T>) -> impl Draw<T> {
+    a
+}
+pub const fn x_pull <T: Screen> (x: T::Unit, a: impl Draw<T>) -> impl Draw<T> {
+    a
+}
+
+pub const fn y_push <T: Screen> (x: T::Unit, a: impl Draw<T>) -> impl Draw<T> {
+    a
+}
+pub const fn y_pull <T: Screen> (x: T::Unit, a: impl Draw<T>) -> impl Draw<T> {
+    a
+}
+