establish db

apps/web/src/lib/db/index.ts

@@ -0,0 +1,62 @@
+/**
+ * Drizzle ORM Database Client for Turso/libSQL.
+ *
+ * Provides the configured drizzle instance and convenience helpers.
+ * Reads DATABASE_URL and DATABASE_TOKEN from environment.
+ */
+
+import { sql } from "drizzle-orm";
+import { drizzle, type LibSQLDatabase } from "drizzle-orm/libsql";
+import { createClient } from "@libsql/client";
+import * as schema from "./schema";
+
+export type { PlantRow, PlantInsert, DiseaseRow, DiseaseInsert } from "./schema";
+
+export { schema };
+
+let _db: LibSQLDatabase<typeof schema> | null = null;
+let _client: ReturnType<typeof createClient> | null = null;
+
+/** Get or create the Drizzle database instance (singleton). */
+export function getDb(): LibSQLDatabase<typeof schema> {
+  if (_db) return _db;
+
+  const url = process.env.DATABASE_URL;
+  const token = process.env.DATABASE_TOKEN;
+
+  if (!url) {
+    throw new Error(
+      "DATABASE_URL is not set. Check your .env.development or .env.production file.",
+    );
+  }
+  if (!token) {
+    throw new Error(
+      "DATABASE_TOKEN is not set. Check your .env.development or .env.production file.",
+    );
+  }
+
+  _client = createClient({ url, authToken: token });
+  _db = drizzle(_client, { schema });
+  return _db;
+}
+
+/** Check database connectivity. */
+export async function checkConnection(): Promise<boolean> {
+  try {
+    const db = getDb();
+    const result = await db.run(sql`SELECT 1 AS ok`);
+    return result.rowsAffected >= 0;
+  } catch (err) {
+    console.error("[DB] Connection failed:", err);
+    return false;
+  }
+}
+
+/** Close the client connection. */
+export function closeDb() {
+  if (_client) {
+    _client.close();
+    _client = null;
+    _db = null;
+  }
+}