feat: initial commit

2026-01-01 03:40:41 +08:00
commit 631f8ed771
98 changed files with 14776 additions and 0 deletions
@@ -0,0 +1,41 @@
+using MaigoLabs.NeedLe.Common;
+
+namespace MaigoLabs.NeedLe.Indexer.Trie;
+
+public static class TrieSerializer
+{
+    private class NodeEntry
+    {
+        public int Id { get; set; }
+        public bool Visited { get; set; }
+        public int[]? Data { get; set; }
+    }
+
+    public static int[] Serialize(TrieNode root)
+    {
+        var nodeEntries = new Dictionary<TrieNode, NodeEntry>();
+        var currentId = 0;
+        NodeEntry GetNodeEntry(TrieNode node) => nodeEntries.TryGetValue(node, out var nodeEntry) ? nodeEntry :
+            nodeEntries[node] = new NodeEntry { Id = ++currentId, Visited = false, Data = null };
+        int SerializeNode(TrieNode node)
+        {
+            var entry = GetNodeEntry(node);
+            if (entry.Visited) return entry.Id;
+            entry.Visited = true;
+            var children = node.Children.Select(child => (CodePoint: child.Key, ChildId: SerializeNode(child.Value))).ToArray();
+            entry.Data =
+            [
+                node.Parent != null ? GetNodeEntry(node.Parent).Id : 0,
+                .. children.Select(child => child.CodePoint),
+                .. children.Select(child => child.ChildId),
+                // End of children list (<= 0 are not valid code points nor node IDs)
+                .. node.TokenIds.Count > 0
+                    ? node.TokenIds.Select(tokenId => -(tokenId + 1)) // Use the negative value of (tokenId + 1)
+                    : [0], // End of children list, no token IDs (token IDs are encoded to negative values)
+            ];
+            return entry.Id;
+        }
+        SerializeNode(root);
+        return nodeEntries.Values.OrderBy(entry => entry.Id).SelectMany(entry => entry.Data ?? []).ToArray();
+    }
+}