feat: add core modules (config, state, diff, apply, health)

state.py

@@ -0,0 +1,106 @@
+import sqlite3
+import threading
+from datetime import datetime, timezone
+
+
+class SyncState:
+    def __init__(self, db_path="./sync.db"):
+        self.db_path = db_path
+        self._lock = threading.Lock()
+        self._conn = sqlite3.connect(db_path, timeout=30)
+        self._conn.execute("PRAGMA journal_mode=WAL")
+        self._conn.execute("""
+            CREATE TABLE IF NOT EXISTS events (
+                uid TEXT PRIMARY KEY,
+                content_hash TEXT NOT NULL,
+                synced_at TIMESTAMP NOT NULL
+            )
+        """)
+        self._conn.execute("""
+            CREATE TABLE IF NOT EXISTS ics_cache (
+                id INTEGER PRIMARY KEY CHECK(id=1),
+                ics_hash TEXT,
+                etag TEXT,
+                fetched_at TIMESTAMP
+            )
+        """)
+        self._conn.commit()
+        return self
+
+    def get_event_uids(self) -> set[str]:
+        with self._lock:
+            cur = self._conn.execute("SELECT uid FROM events")
+            return {row[0] for row in cur.fetchall()}
+
+    def get_event_hash(self, uid: str) -> str | None:
+        with self._lock:
+            cur = self._conn.execute("SELECT content_hash FROM events WHERE uid = ?", (uid,))
+            row = cur.fetchone()
+            return row[0] if row else None
+
+    def upsert_event(self, uid: str, content_hash: str) -> None:
+        with self._lock:
+            self._conn.execute("""
+                INSERT OR REPLACE INTO events (uid, content_hash, synced_at)
+                VALUES (?, ?, ?)
+            """, (uid, content_hash, datetime.now(timezone.utc).isoformat()))
+            self._conn.commit()
+
+    def delete_event(self, uid: str) -> None:
+        with self._lock:
+            self._conn.execute("DELETE FROM events WHERE uid = ?", (uid,))
+            self._conn.commit()
+
+    def clear_events(self) -> int:
+        with self._lock:
+            cur = self._conn.execute("SELECT COUNT(*) FROM events")
+            count = cur.fetchone()[0]
+            self._conn.execute("DELETE FROM events")
+            self._conn.commit()
+            return count
+
+    def get_ics_cache(self) -> tuple[str | None, str | None, str | None]:
+        with self._lock:
+            cur = self._conn.execute("SELECT ics_hash, etag, fetched_at FROM ics_cache WHERE id = 1")
+            row = cur.fetchone()
+            if row:
+                return (row[0], row[1], row[2])
+            return (None, None, None)
+
+    def set_ics_cache(self, ics_hash: str, etag: str | None) -> None:
+        with self._lock:
+            self._conn.execute("""
+                INSERT INTO ics_cache (id, ics_hash, etag, fetched_at)
+                VALUES (1, ?, ?, ?)
+                ON CONFLICT(id) DO UPDATE SET ics_hash = ?, etag = ?, fetched_at = ?
+            """, (ics_hash, etag, datetime.now(timezone.utc).isoformat(),
+                   ics_hash, etag, datetime.now(timezone.utc).isoformat()))
+            self._conn.commit()
+
+    def clear_ics_cache(self) -> None:
+        with self._lock:
+            self._conn.execute("DELETE FROM ics_cache")
+            self._conn.commit()
+
+    def snapshot(self) -> dict:
+        with self._lock:
+            cur = self._conn.execute("SELECT uid, content_hash FROM events")
+            rows = cur.fetchall()
+            return {
+                "uids": [r[0] for r in rows],
+                "hashes": {r[0]: r[1] for r in rows}
+            }
+
+    def restore_snapshot(self, data: dict) -> None:
+        with self._lock:
+            self._conn.execute("DELETE FROM events")
+            for uid, content_hash in data.get("hashes", {}).items():
+                self._conn.execute("""
+                    INSERT INTO events (uid, content_hash, synced_at)
+                    VALUES (?, ?, ?)
+                """, (uid, content_hash, datetime.now(timezone.utc).isoformat()))
+            self._conn.commit()
+
+    def close(self) -> None:
+        with self._lock:
+            self._conn.close()