1 files changed, 97 insertions, 0 deletions
diff --git a/packages/doc/src/lib.rs b/packages/doc/src/lib.rs
new file mode 100644
index 0000000..a1d7497
--- /dev/null
+++ b/packages/doc/src/lib.rs
@@ -0,0 +1,97 @@
+use thiserror::Error;
+use uuid::Uuid;
+use wasm_bindgen::prelude::*;
+
+use crate::{
+    doc::{ApplyOpError, Doc},
+    op::{CreateGrid, Op, OpKind},
+    vector_clock::VectorClock,
+};
+
+mod doc;
+mod op;
+mod vector_clock;
+
+#[derive(Error, Debug)]
+pub enum Error {
+    #[error("error while realizing state")]
+    RealizeError(#[from] ApplyOpError),
+}
+
+#[wasm_bindgen]
+pub struct State {
+    actor_id: Uuid,
+    ops: Vec<Op>,
+}
+
+#[wasm_bindgen]
+impl State {
+    #[wasm_bindgen(constructor)]
+    pub fn new() -> Self {
+        let actor_id = Uuid::now_v7();
+
+        Self {
+            actor_id,
+            ops: vec![],
+        }
+    }
+
+    pub fn create_grid(&mut self) {
+        self.append_op(OpKind::CreateGrid(CreateGrid {
+            rows: 4,
+            base_cells_per_row: 16,
+        }));
+    }
+
+    pub fn to_json(&self) -> JsValue {
+        let doc = self.realize().unwrap();
+        serde_wasm_bindgen::to_value(&doc).unwrap()
+    }
+}
+
+impl State {
+    pub fn append_op(&mut self, kind: OpKind) {
+        let clock = self
+            .ops
+            .last()
+            .map(|op| op.clock.inc(&self.actor_id))
+            .unwrap_or_else(|| VectorClock::new().inc(&self.actor_id));
+
+        self.ops.push(Op {
+            id: Uuid::now_v7(),
+            clock,
+            kind,
+        });
+    }
+
+    pub fn realize(&self) -> Result<Doc, Error> {
+        let mut doc = Doc::default();
+
+        for op in &self.ops {
+            doc.apply_op(op)?;
+        }
+
+        Ok(doc)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::op::CreateGrid;
+
+    use super::*;
+
+    #[test]
+    fn test() {
+        let mut state = State::new();
+
+        state.append_op(OpKind::CreateGrid(CreateGrid {
+            rows: 4,
+            base_cells_per_row: 16,
+        }));
+
+        let doc = state.realize().unwrap();
+        let grid = doc.grids.first().unwrap();
+        assert_eq!(grid.rows.len(), 4);
+    }
+}