Initial commit

src/meshbot/db.py

@@ -0,0 +1,67 @@
+"""SQLite persistence for per-sender conversation history."""
+
+from __future__ import annotations
+
+import sqlite3
+from pathlib import Path
+
+SCHEMA = """
+CREATE TABLE IF NOT EXISTS conversations (
+    public_key   TEXT PRIMARY KEY,
+    contact_name TEXT,
+    created_at   TEXT NOT NULL DEFAULT (datetime('now')),
+    updated_at   TEXT NOT NULL DEFAULT (datetime('now'))
+);
+
+CREATE TABLE IF NOT EXISTS messages (
+    id          INTEGER PRIMARY KEY AUTOINCREMENT,
+    public_key  TEXT NOT NULL REFERENCES conversations(public_key),
+    role        TEXT NOT NULL CHECK (role IN ('user', 'assistant')),
+    content     TEXT NOT NULL,
+    created_at  TEXT NOT NULL DEFAULT (datetime('now'))
+);
+
+CREATE INDEX IF NOT EXISTS idx_messages_pubkey_id
+    ON messages(public_key, id);
+"""
+
+
+def connect(path: str | Path) -> sqlite3.Connection:
+    """Open the SQLite DB, ensure the parent dir and schema exist, return the connection."""
+    db_path = Path(path)
+    db_path.parent.mkdir(parents=True, exist_ok=True)
+    conn = sqlite3.connect(db_path, isolation_level=None)  # autocommit
+    conn.row_factory = sqlite3.Row
+    conn.execute("PRAGMA journal_mode = WAL;")
+    conn.execute("PRAGMA foreign_keys = ON;")
+    conn.executescript(SCHEMA)
+    return conn
+
+
+def upsert_conversation(conn: sqlite3.Connection, public_key: str, contact_name: str) -> None:
+    conn.execute(
+        """
+        INSERT INTO conversations (public_key, contact_name)
+        VALUES (?, ?)
+        ON CONFLICT(public_key) DO UPDATE SET
+            contact_name = excluded.contact_name,
+            updated_at   = datetime('now')
+        """,
+        (public_key, contact_name),
+    )
+
+
+def add_message(conn: sqlite3.Connection, public_key: str, role: str, content: str) -> None:
+    conn.execute(
+        "INSERT INTO messages (public_key, role, content) VALUES (?, ?, ?)",
+        (public_key, role, content),
+    )
+
+
+def get_history(conn: sqlite3.Connection, public_key: str) -> list[dict[str, str]]:
+    """Return the conversation as OpenAI chat messages, oldest first."""
+    rows = conn.execute(
+        "SELECT role, content FROM messages WHERE public_key = ? ORDER BY id ASC",
+        (public_key,),
+    ).fetchall()
+    return [{"role": row["role"], "content": row["content"]} for row in rows]