Added sqlite

lib/services/db_schema.dart

@@ -0,0 +1,61 @@
+const createVehiclesTableSql = '''
+  CREATE TABLE vehicles (
+    id TEXT PRIMARY KEY,
+    make TEXT NOT NULL,
+    model TEXT NOT NULL,
+    color TEXT NOT NULL,
+    license_plate TEXT NOT NULL,
+    updated_at INTEGER NOT NULL,
+    deleted_at INTEGER,
+    dirty INTEGER NOT NULL DEFAULT 1
+  )
+''';
+
+const createFuelEntriesTableSql = '''
+  CREATE TABLE fuel_entries (
+    id TEXT PRIMARY KEY,
+    vehicle_id TEXT NOT NULL,
+    date INTEGER NOT NULL,
+    gallons REAL NOT NULL,
+    price_per_gallon REAL NOT NULL,
+    total_cost REAL NOT NULL,
+    receipt_image_path TEXT,
+    receipt_drive_file_id TEXT,
+    updated_at INTEGER NOT NULL,
+    deleted_at INTEGER,
+    dirty INTEGER NOT NULL DEFAULT 1
+  )
+''';
+
+const createFuelEntriesIndexSql =
+    'CREATE INDEX idx_fuel_entries_vehicle_id ON fuel_entries(vehicle_id)';
+
+/// Merges attached `remote_db` rows into `main` (the live local database):
+/// any remote row that's new to us, or newer than our copy, replaces ours.
+/// Rows this doesn't touch — including our own not-yet-pushed edits — are
+/// left alone, since the WHERE clause only matches rows remote should win;
+/// no separate "keep local" statement is needed.
+const mergeVehiclesSql = '''
+  INSERT OR REPLACE INTO main.vehicles
+    (id, make, model, color, license_plate, updated_at, deleted_at, dirty)
+  SELECT r.id, r.make, r.model, r.color, r.license_plate, r.updated_at, r.deleted_at, 0
+  FROM remote_db.vehicles r
+  LEFT JOIN main.vehicles l ON l.id = r.id
+  WHERE l.id IS NULL OR r.updated_at > l.updated_at
+''';
+
+/// Same rule as [mergeVehiclesSql]. `receipt_image_path` is always forced
+/// to NULL on the merged-in copy — it's a local filesystem path, meaningless
+/// (and never valid) on another device, and rows are only ever pushed to
+/// Drive once their pending receipt has already been uploaded there, so a
+/// remote row should never legitimately have one anyway.
+const mergeFuelEntriesSql = '''
+  INSERT OR REPLACE INTO main.fuel_entries
+    (id, vehicle_id, date, gallons, price_per_gallon, total_cost,
+     receipt_image_path, receipt_drive_file_id, updated_at, deleted_at, dirty)
+  SELECT r.id, r.vehicle_id, r.date, r.gallons, r.price_per_gallon, r.total_cost,
+         NULL, r.receipt_drive_file_id, r.updated_at, r.deleted_at, 0
+  FROM remote_db.fuel_entries r
+  LEFT JOIN main.fuel_entries l ON l.id = r.id
+  WHERE l.id IS NULL OR r.updated_at > l.updated_at
+''';