Initial commit

skills/debate-orchestrator/debate_ops/frontmatter.py

@@ -0,0 +1,80 @@
+"""JSON frontmatter parsing - zero dependencies."""
+from __future__ import annotations
+
+import json
+from dataclasses import dataclass
+from pathlib import Path
+from typing import Any
+
+
+@dataclass
+class Document:
+    metadata: dict[str, Any]
+    content: str
+
+    def __getitem__(self, key: str) -> Any:
+        return self.metadata[key]
+
+    def get(self, key: str, default: Any = None) -> Any:
+        return self.metadata.get(key, default)
+
+
+def _find_json_end(text: str) -> int:
+    depth = in_string = escape_next = 0
+    for i, char in enumerate(text):
+        if escape_next:
+            escape_next = 0
+            continue
+        if char == '\\':
+            escape_next = 1
+            continue
+        if char == '"' and not escape_next:
+            in_string = not in_string
+            continue
+        if in_string:
+            continue
+        if char == '{':
+            depth += 1
+        elif char == '}':
+            depth -= 1
+            if depth == 0:
+                return i + 1
+    return -1
+
+
+def parse(text: str) -> Document:
+    text = text.lstrip()
+    if not text.startswith('{'):
+        raise ValueError("JSON frontmatter must start with '{'")
+
+    end_pos = _find_json_end(text)
+    if end_pos == -1:
+        raise ValueError("JSON frontmatter not properly closed")
+
+    try:
+        metadata = json.loads(text[:end_pos])
+    except json.JSONDecodeError as e:
+        raise ValueError(f"Invalid JSON in frontmatter: {e}")
+
+    if not isinstance(metadata, dict):
+        raise ValueError("JSON frontmatter must be object")
+
+    return Document(metadata=metadata, content=text[end_pos:].lstrip('\n'))
+
+
+def dumps(metadata: dict[str, Any], content: str) -> str:
+    return f"{json.dumps(metadata, indent=2)}\n\n{content}"
+
+
+def load(filepath: Path | str) -> Document:
+    return parse(Path(filepath).read_text())
+
+
+def dump(doc: Document, filepath: Path | str) -> None:
+    Path(filepath).write_text(dumps(doc.metadata, doc.content))
+
+
+def update_metadata(filepath: Path | str, **updates: Any) -> None:
+    doc = load(filepath)
+    doc.metadata.update(updates)
+    dump(doc, filepath)