# 3. Set Up Database

Set up functions for different environments (Node.js, web browsers, and React Native) to manage LevelDB databases:

* **Node.js Setup**: Utilizes `leveldown` for creating databases. Use `createNodeDatabase(path)` to instantiate a LevelDown database at the given file path.

  ```typescript
  const db = createNodeDatabase('./path/to/database');
  ```
* **Web Browser Setup**: Leverages `level-js` for browser-based databases. Use `createWebDatabase(path)` to initialize a LevelDB database, offering basic functionality through the `LevelDB` instance.

  ```typescript
  const db = createWebDatabase('./data/mydb');
  ```
* **React Native Setup**: Employs `leveldown-nodejs-mobile` for creating databases on React Native platforms. Use the asynchronous `createNativeDatabase(path)` function, which returns a promise that resolves to a `LeveldownNodejsMobile` database instance.

  ```typescript
  const db = await createNativeDatabase('/path/to/database');

  ```

````typescript
// Setup for Node builds.
import LevelDownDB from "leveldown";
/**
 * Creates a LevelDown database instance at the specified path.
 *
 * @param dbLocationPath - The file system path where the database will be created
 * @returns A LevelDown database instance
 *
 * @example
 * ```typescript
 * const db = createNodeDatabase('./path/to/database');
 * ```
 */
export const createNodeDatabase = (dbLocationPath: string) => {
  console.log("Creating local database at path: ", dbLocationPath);
  const db = LevelDownDB(dbLocationPath);
  return db;
};

// Setup for Web builds.
import LevelDB from "level-js";
/**
 * Creates a new web database instance at the specified location path
 * @param dbLocationPath - The file system path where the database will be created
 * @returns A new LevelDB database instance
 * @remarks This function initializes a new LevelDB database at the specified path
 * and provides basic database functionality through the returned instance.
 * @example
 * const db = createWebDatabase('./data/mydb');
 */
export const createWebDatabase = (dbLocationPath: string) => {
  indexedDB.databases;
  console.log("Creating local database at path: ", dbLocationPath);
  const db = new LevelDB(dbLocationPath);
  return db;
};

// Setup for React Native builds.

// @ts-ignore
import LeveldownNodejsMobile from "leveldown-nodejs-mobile";
/**
 * Creates a native database instance using LeveldownNodejsMobile.
 *
 * @param dbLocationPath - The file system path where the database will be stored
 * @returns A Promise that resolves to a new LeveldownNodejsMobile database instance
 *
 * @example
 * ```typescript
 * const db = await createNativeDatabase('/path/to/database');
 * ```
 */
export const createNativeDatabase = async (dbLocationPath: string) => {
  return new LeveldownNodejsMobile(dbLocationPath);
};
````


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