1 | use crate::{ |
2 | grid::config::Entity, |
3 | grid::records::{ExactRecords, Records}, |
4 | settings::object::Object, |
5 | }; |
6 | |
7 | /// Frame includes cells which are on the edges of each side. |
8 | /// Therefore it's [`Object`] implementation returns a subset of cells which are present in frame. |
9 | #[derive (Debug)] |
10 | pub struct Frame; |
11 | |
12 | impl<I> Object<I> for Frame |
13 | where |
14 | I: Records + ExactRecords, |
15 | { |
16 | type Iter = FrameIter; |
17 | |
18 | fn cells(&self, records: &I) -> Self::Iter { |
19 | FrameIter::new(records.count_rows(), records.count_columns()) |
20 | } |
21 | } |
22 | |
23 | /// An [`Iterator`] which goes goes over all cell on a frame of a [`Table`]. |
24 | /// |
25 | /// [`Table`]: crate::Table |
26 | #[derive (Debug)] |
27 | pub struct FrameIter { |
28 | rows: usize, |
29 | cols: usize, |
30 | row: usize, |
31 | col: usize, |
32 | } |
33 | |
34 | impl FrameIter { |
35 | const fn new(count_rows: usize, count_columns: usize) -> Self { |
36 | Self { |
37 | rows: count_rows, |
38 | cols: count_columns, |
39 | row: 0, |
40 | col: 0, |
41 | } |
42 | } |
43 | } |
44 | |
45 | impl Iterator for FrameIter { |
46 | type Item = Entity; |
47 | |
48 | fn next(&mut self) -> Option<Self::Item> { |
49 | if self.cols == 0 || self.rows == 0 { |
50 | return None; |
51 | } |
52 | |
53 | if self.row == self.rows { |
54 | return None; |
55 | } |
56 | |
57 | let row = self.row; |
58 | let col = self.col; |
59 | |
60 | self.col += 1; |
61 | |
62 | if self.col == self.cols { |
63 | self.row += 1; |
64 | self.col = 0; |
65 | } |
66 | |
67 | Some(Entity::Cell(row, col)) |
68 | } |
69 | } |
70 | |