feat: add basic grid random generation

src/gen.rs

@@ -0,0 +1 @@
+mod basic;

src/gen/basic.rs

@@ -0,0 +1,110 @@
+//! Basic grid generation given a height, width and a seed.
+
+use crate::grid::Grid;
+use rand::{Rng, SeedableRng};
+use rand_chacha::ChaCha8Rng;
+
+/// Basic grid generator.
+///
+/// TODO: Make width and height integer type generic?
+pub struct BasicGridGenerator {
+    width: u8,
+    height: u8,
+    seed: u64,
+}
+
+impl BasicGridGenerator {
+    pub fn new(width: u8, height: u8, seed: u64) -> Self {
+        Self {
+            width,
+            height,
+            seed,
+        }
+    }
+
+    pub fn generate(&self) -> Grid {
+        let mut rng = ChaCha8Rng::seed_from_u64(self.seed);
+
+        let cells: Vec<_> = (0..self.width)
+            .into_iter()
+            .map(|_| {
+                (0..self.height)
+                    .into_iter()
+                    .map(|_| rng.gen())
+                    .collect::<Vec<_>>()
+            })
+            .collect();
+        Grid::with_cells(cells)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::grid::{Cell, Grid};
+
+    use super::BasicGridGenerator;
+
+    #[test]
+    fn ensure_grid_5x5_0_is_reproducible() {
+        let gen = BasicGridGenerator::new(5, 5, 0);
+        let grid = gen.generate();
+        println!("grid {:#?}", grid);
+        let expected_grid = Grid::with_cells(vec![
+            vec![
+                Cell::Empty,
+                Cell::Filled,
+                Cell::Empty,
+                Cell::Filled,
+                Cell::Empty,
+            ],
+            vec![
+                Cell::Filled,
+                Cell::Empty,
+                Cell::Empty,
+                Cell::Empty,
+                Cell::Filled,
+            ],
+            vec![
+                Cell::Empty,
+                Cell::Empty,
+                Cell::Filled,
+                Cell::Filled,
+                Cell::Empty,
+            ],
+            vec![
+                Cell::Filled,
+                Cell::Filled,
+                Cell::Filled,
+                Cell::Filled,
+                Cell::Empty,
+            ],
+            vec![
+                Cell::Empty,
+                Cell::Empty,
+                Cell::Filled,
+                Cell::Empty,
+                Cell::Empty,
+            ],
+        ]);
+
+        assert_eq!(grid, expected_grid);
+    }
+
+    #[test]
+    fn grid_5x5_u64_max_hints() {
+        let gen = BasicGridGenerator::new(5, 5, u64::MAX);
+        let grid = gen.generate();
+        println!("grid {:#?}", grid);
+
+        let (r_hints, c_hints) = grid.hints();
+        assert_eq!(
+            r_hints,
+            [vec![4], vec![1, 1], vec![1, 1], vec![1, 2], vec![1, 2]]
+        );
+
+        assert_eq!(
+            c_hints,
+            [vec![1], vec![3, 1], vec![1, 1], vec![2, 2], vec![1, 1, 1]]
+        );
+    }
+}

src/lib.rs

@@ -1 +1,2 @@
-mod core;
+mod gen;
+mod grid;