global: snapshot

crates/brk_iterator/src/iterator.rs

@@ -0,0 +1,55 @@
+use brk_structs::Block;
+
+use crate::State;
+
+pub struct BlockIterator(State);
+
+impl BlockIterator {
+    pub fn new(state: State) -> Self {
+        Self(state)
+    }
+}
+
+impl Iterator for BlockIterator {
+    type Item = Block;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match &mut self.0 {
+            State::Rpc {
+                client,
+                heights,
+                prev_hash,
+            } => {
+                let height = heights.next()?;
+                let hash = client.get_block_hash(height).ok()?;
+                let block = client.get_block(&hash).ok()?;
+
+                if prev_hash
+                    .as_ref()
+                    .is_some_and(|prev_hash| block.header.prev_blockhash != prev_hash.into())
+                {
+                    return None;
+                }
+
+                prev_hash.replace(hash.clone());
+
+                Some(Block::from((height, hash, block)))
+            }
+            State::Reader {
+                receiver,
+                after_hash,
+            } => {
+                let block = Block::from(receiver.recv().ok()?);
+
+                // Only validate the first block (Reader validates the rest)
+                if let Some(expected_prev) = after_hash.take()
+                    && block.header.prev_blockhash != expected_prev.into()
+                {
+                    return None;
+                }
+
+                Some(block)
+            }
+        }
+    }
+}