1k-date-formatting

# Date Formatting

Guidelines for consistent date and time formatting across OneKey applications.

## Critical Rule

**NEVER use native JavaScript date methods:**
```typescript
// ❌ FORBIDDEN
date.toLocaleDateString()
date.toLocaleString()
date.toISOString()
new Intl.DateTimeFormat().format(date)

// ✅ CORRECT
import { formatDate } from '@onekeyhq/shared/src/utils/dateUtils';
formatDate(date, { hideSeconds: true });
```

## Quick Reference

| Function | Use Case | Example Output |
|----------|----------|----------------|
| `formatDate(date, options?)` | Full date and time | `2024/01/15, 14:30` |
| `formatTime(date, options?)` | Time only | `14:30:45` |
| `formatRelativeDate(date)` | Relative display | `Today`, `Yesterday` |
| `formatDistanceToNow(date)` | Time distance | `2 hours ago` |
| `formatDateFns(date, format?)` | Custom format | Based on template |

## Common Patterns

### Transaction History
```typescript
import { formatDate } from '@onekeyhq/shared/src/utils/dateUtils';

// Hide year if current year, hide seconds
<SizableText>
  {formatDate(item.createdAt, { hideTheYear: true, hideSeconds: true })}
</SizableText>
```

### Custom Format
```typescript
// Use format template
{formatDate(item.timestamp, { formatTemplate: 'yyyy-LL-dd HH:mm' })}
```

### React Hook (for dynamic updates)
```typescript
import useFormatDate from '@onekeyhq/kit/src/hooks/useFormatDate';

function MyComponent() {
  const { formatDate } = useFormatDate();
  return <SizableText>{formatDate(date, { hideSeconds: true })}</SizableText>;
}
```

## Format Options

```typescript
interface IFormatDateOptions {
  hideYear?: boolean;        // Always hide year
  hideMonth?: boolean;       // Always hide month
  hideTheYear?: boolean;     // Hide year if current year
  hideTheMonth?: boolean;    // Hide month if current month
  hideTimeForever?: boolean; // Hide time portion
  hideSeconds?: boolean;     // Hide seconds (HH:mm)
  formatTemplate?: string;   // Custom date-fns format
}
```

## Detailed Guide

For comprehensive date formatting rules and examples, see [date-formatting.md](references/rules/date-formatting.md).

Topics covered:
- Core utilities from `@onekeyhq/shared/src/utils/dateUtils`
- Available formatting functions
- Options reference and format templates
- Common patterns for transactions, history, and relative time
- React hooks for dynamic updates
- Locale-aware formatting
- Real-world examples
- Troubleshooting

## Key Files

| Purpose | File Path |
|---------|-----------|
| Core utilities | `packages/shared/src/utils/dateUtils.ts` |
| React hook | `packages/kit/src/hooks/useFormatDate.ts` |
| Locale mapping | `packages/shared/src/locale/dateLocaleMap.ts` |

## Related Skills

- `/1k-i18n` - Internationalization and locale handling
- `/1k-coding-patterns` - General coding patterns