# Environment Variables

Utilities for parsing environment variables as boolean or numeric values.

## getBooleanEnv

Parses an environment variable value into a boolean.

```typescript
import { getBooleanEnv } from "@triplef/helpers/get-boolean-env";
```

### Signature

```typescript
function getBooleanEnv(
  value?: string | null,
  fallback?: boolean
): boolean | null;
```

### Parameters

| Parameter  | Type                          | Description                               |
| ---------- | ----------------------------- | ----------------------------------------- |
| `value`    | `string \| null \| undefined` | The environment variable value to parse   |
| `fallback` | `boolean` (optional)          | Fallback value if input is undefined/null |

### Returns

- `true` if the value starts with `"true"` (case-insensitive)
- `false` if the value starts with anything else
- `fallback` if provided and value is undefined/null
- `null` if no fallback provided and value is undefined/null

### Examples

```typescript
getBooleanEnv("true"); // true
getBooleanEnv("TRUE"); // true
getBooleanEnv("false"); // false
getBooleanEnv("0"); // false
getBooleanEnv("anything"); // false
getBooleanEnv(undefined, false); // false
getBooleanEnv(null, true); // true
getBooleanEnv(undefined); // null
```

---

## getByteSizeEnv

Parses an environment variable string into bytes. Supports units: B, KB, MB, GB, TB.

```typescript
import { getByteSizeEnv } from "@triplef/helpers/get-byte-size-env";
```

### Signature

```typescript
function getByteSizeEnv(
  value?: string | null,
  fallback?: number
): number | null;
```

### Parameters

| Parameter  | Type                          | Description                             |
| ---------- | ----------------------------- | --------------------------------------- |
| `value`    | `string \| null \| undefined` | The environment variable value to parse |
| `fallback` | `number` (optional)           | Fallback value if parsing fails         |

### Examples

```typescript
getByteSizeEnv("100B"); // 100
getByteSizeEnv("1KB"); // 1024
getByteSizeEnv("1MB"); // 1048576
getByteSizeEnv("1.5GB"); // 1610612736
getByteSizeEnv("1tb"); // 1099511627776
getByteSizeEnv(null, 1024); // 1024
getByteSizeEnv("invalid", 0); // 0
getByteSizeEnv(undefined); // null
```

---

## getNumberEnv

Parses an environment variable string into a number, supporting both integers and floats. Automatically normalizes commas to periods for European decimal notation.

```typescript
import { getNumberEnv } from "@triplef/helpers/get-number-env";
```

### Signature

```typescript
function getNumberEnv(
  value?: string | null,
  fallback?: number
): number | bigint | null;
```

### Parameters

| Parameter  | Type                          | Description                             |
| ---------- | ----------------------------- | --------------------------------------- |
| `value`    | `string \| null \| undefined` | The environment variable value to parse |
| `fallback` | `number` (optional)           | Fallback value if parsing fails         |

### Resolution Order

1. Parses the provided string
2. Falls back to `fallback` if value is null, undefined, or invalid
3. Returns `null` if parsing fails and no fallback provided

### Examples

```typescript
getNumberEnv("42"); // 42
getNumberEnv("3.14"); // 3.14
getNumberEnv("1,5"); // 1.5 (comma normalized)
getNumberEnv(null, 10); // 10
getNumberEnv("invalid", 0); // 0
getNumberEnv(undefined); // null
getNumberEnv(""); // null
```