Initial native Linux parental control application

app/database.py

@@ -0,0 +1,105 @@
+import sqlite3
+from pathlib import Path
+from contextlib import contextmanager
+
+BASE_DIR = Path(__file__).resolve().parent.parent
+
+DATABASE_DIR = BASE_DIR / "data"
+DATABASE_PATH = DATABASE_DIR / "parental-control.db"
+
+
+def initialize_database():
+    DATABASE_DIR.mkdir(parents=True, exist_ok=True)
+
+    with sqlite3.connect(DATABASE_PATH) as db:
+        db.execute("PRAGMA foreign_keys = ON")
+
+        db.executescript(
+            """
+            CREATE TABLE IF NOT EXISTS users (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                username TEXT NOT NULL UNIQUE,
+                enabled INTEGER NOT NULL DEFAULT 1,
+                created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP
+            );
+
+            CREATE TABLE IF NOT EXISTS daily_allowances (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id INTEGER NOT NULL,
+                weekday INTEGER NOT NULL,
+                allowance_seconds INTEGER NOT NULL DEFAULT 0,
+
+                UNIQUE(user_id, weekday),
+
+                FOREIGN KEY(user_id)
+                    REFERENCES users(id)
+                    ON DELETE CASCADE
+            );
+
+            CREATE TABLE IF NOT EXISTS access_windows (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id INTEGER NOT NULL,
+                weekday INTEGER NOT NULL,
+                start_minute INTEGER NOT NULL,
+                end_minute INTEGER NOT NULL,
+
+                FOREIGN KEY(user_id)
+                    REFERENCES users(id)
+                    ON DELETE CASCADE
+            );
+
+            CREATE TABLE IF NOT EXISTS usage (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id INTEGER NOT NULL,
+                date TEXT NOT NULL,
+                used_seconds INTEGER NOT NULL DEFAULT 0,
+
+                UNIQUE(user_id, date),
+
+                FOREIGN KEY(user_id)
+                    REFERENCES users(id)
+                    ON DELETE CASCADE
+            );
+
+            CREATE TABLE IF NOT EXISTS temporary_grants (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id INTEGER NOT NULL,
+                seconds INTEGER NOT NULL,
+                remaining_seconds INTEGER NOT NULL,
+                created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
+                expires_at TEXT,
+                consumed INTEGER NOT NULL DEFAULT 0,
+                FOREIGN KEY(user_id) REFERENCES users(id) ON DELETE CASCADE
+            );
+
+            CREATE TABLE IF NOT EXISTS events (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id INTEGER,
+                event_type TEXT NOT NULL,
+                details TEXT,
+                created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+                FOREIGN KEY(user_id)
+                    REFERENCES users(id)
+                    ON DELETE SET NULL
+            );
+            """
+        )
+
+        db.commit()
+
+
+@contextmanager
+def get_db():
+    db = sqlite3.connect(DATABASE_PATH)
+    db.row_factory = sqlite3.Row
+    db.execute("PRAGMA foreign_keys = ON")
+
+    try:
+        yield db
+        db.commit()
+    except Exception:
+        db.rollback()
+        raise
+    finally:
+        db.close()