use crate::*;
use std::fmt::Debug;

pub trait Area<N: Coordinate>: From<[N;4]> + Debug + Copy {
    fn x (&self) -> N;
    fn y (&self) -> N;
    fn w (&self) -> N;
    fn h (&self) -> N;
    #[inline] fn expect_min (&self, w: N, h: N) -> Usually<&Self> {
        if self.w() < w || self.h() < h {
            Err(format!("min {w}x{h}").into())
        } else {
            Ok(self)
        }
    }
    #[inline] fn xy (&self) -> [N;2] {
        [self.x(), self.y()]
    }
    #[inline] fn wh (&self) -> [N;2] {
        [self.w(), self.h()]
    }
    #[inline] fn xywh (&self) -> [N;4] {
        [self.x(), self.y(), self.w(), self.h()]
    }
    #[inline] fn clip_h (&self, h: N) -> [N;4] {
        [self.x(), self.y(), self.w(), self.h().min(h)]
    }
    #[inline] fn clip_w (&self, w: N) -> [N;4] {
        [self.x(), self.y(), self.w().min(w), self.h()]
    }
    #[inline] fn clip (&self, wh: impl Size<N>) -> [N;4] {
        [self.x(), self.y(), wh.w(), wh.h()]
    }
    #[inline] fn set_w (&self, w: N) -> [N;4] {
        [self.x(), self.y(), w, self.h()]
    }
    #[inline] fn set_h (&self, h: N) -> [N;4] {
        [self.x(), self.y(), self.w(), h]
    }
    #[inline] fn x2 (&self) -> N {
        self.x() + self.w()
    }
    #[inline] fn y2 (&self) -> N {
        self.y() + self.h()
    }
    #[inline] fn lrtb (&self) -> [N;4] {
        [self.x(), self.x2(), self.y(), self.y2()]
    }
    #[inline] fn center (&self) -> [N;2] {
        [self.x() + self.w()/2.into(), self.y() + self.h()/2.into()]
    }
    #[inline] fn center_x (&self, n: N) -> [N;4] {
        let [x, y, w, h] = self.xywh();
        [(x + w / 2.into()).minus(n / 2.into()), y + h / 2.into(), n, 1.into()]
    }
    #[inline] fn center_y (&self, m: N) -> [N;4] {
        let [x, y, w, h] = self.xywh();
        [x + w / 2.into(), (y + h / 2.into()).minus(m / 2.into()), 1.into(), m]
    }
    #[inline] fn center_xy (&self, [n, m]: [N;2]) -> [N;4] {
        let [x, y, w, h] = self.xywh();
        [(x + w / 2.into()).minus(n / 2.into()), (y + h / 2.into()).minus(m / 2.into()), n, m]
    }
    #[inline] fn centered (&self) -> [N;2] {
        [self.x().minus(self.w()/2.into()), self.y().minus(self.h()/2.into())]
    }
    #[inline] fn zero () -> [N;4] {
        [N::zero(), N::zero(), N::zero(), N::zero()]
    }
    #[inline] fn from_position (pos: impl Size<N>) -> [N;4] {
        let [x, y] = pos.wh();
        [x, y, 0.into(), 0.into()]
    }
    #[inline] fn from_size (size: impl Size<N>) -> [N;4] {
        let [w, h] = size.wh();
        [0.into(), 0.into(), w, h]
    }
}

impl<N: Coordinate> Area<N> for (N, N, N, N) {
    #[inline] fn x (&self) -> N { self.0 }
    #[inline] fn y (&self) -> N { self.1 }
    #[inline] fn w (&self) -> N { self.2 }
    #[inline] fn h (&self) -> N { self.3 }
}

impl<N: Coordinate> Area<N> for [N;4] {
    #[inline] fn x (&self) -> N { self[0] }
    #[inline] fn y (&self) -> N { self[1] }
    #[inline] fn w (&self) -> N { self[2] }
    #[inline] fn h (&self) -> N { self[3] }
}