initial commit with code I worked on in rust-playground

blocktree.rs

@@ -0,0 +1,88 @@
+
+use std::collections::HashMap;
+
+#[derive(Debug)]
+pub struct NoteBlock {
+    // IDs are int64 as this is the datatype of rowids in sqlite
+    id: i64,
+    first_child_id: Option<i64>,
+    next_sibling_id: Option<i64>,
+    
+    content: String
+}
+
+impl NoteBlock {
+    pub fn new(id: i64, first_child_id: Option<i64>, next_sibling_id: Option<i64>, content: String) -> Self {
+        Self {id, first_child_id, next_sibling_id, content}
+    }
+}
+
+#[derive(Debug)]
+struct BlockTreeNode {
+    // a tree of nodes, where each node refers to its block by id.
+    // the id is used as the key in a page's block table.
+    block_id: i64,
+    block_level: Option<usize>,
+    first_child_node: Option<Box<BlockTreeNode>>,
+    next_sibling_node: Option<Box<BlockTreeNode>>
+}
+
+impl BlockTreeNode {
+    pub fn new(block_id: i64) -> Self {
+        BlockTreeNode {
+            block_id,
+            block_level: None,
+            first_child_node: None,
+            next_sibling_node: None
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct NotePage {
+    title: String,
+    id: i64,
+    block_tree_root: BlockTreeNode,
+    
+    block_table: HashMap<i64, NoteBlock>
+}
+
+impl NotePage {
+    pub fn new(title: String, id: i64, root_block: NoteBlock) -> Self {
+        let mut new_page = Self {
+            title, 
+            id, 
+            block_tree_root: BlockTreeNode::new(root_block.id),
+            block_table: HashMap::new()
+        };
+        new_page.block_tree_root.block_level = Some(0);
+        new_page.block_table.insert(root_block.id, root_block);
+        new_page
+    }
+    
+    pub fn insert(self: &mut Self, block: NoteBlock) {
+        self.block_table.insert(block.id, block);
+    }
+    
+    pub fn build_tree(self: &mut Self) {
+        let mut node_stack = Vec::new();
+        node_stack.push(&mut self.block_tree_root);
+        while !node_stack.is_empty() {
+            println!("{:?}", node_stack);
+            let current_node = node_stack.pop().unwrap();
+            let current_block = self.block_table.get(&current_node.block_id).unwrap();
+            if let Some(next_sibling_id) = current_block.next_sibling_id {
+                let mut sibling_node = BlockTreeNode::new(next_sibling_id);
+                sibling_node.block_level = current_node.block_level;
+                current_node.next_sibling_node = Some(Box::new(sibling_node));
+                node_stack.push(current_node.next_sibling_node.as_mut().unwrap());
+            }
+            if let Some(first_child_id) = current_block.first_child_id {
+                let mut child_node = BlockTreeNode::new(first_child_id);
+                child_node.block_level = Some(current_node.block_level.unwrap() + 1);
+                current_node.first_child_node = Some(Box::new(child_node));
+                node_stack.push(current_node.first_child_node.as_mut().unwrap());
+            }
+        }
+    }
+}