sojorn/sojorn_app/lib/utils/country_flag.dart
Patrick Britton 3c4680bdd7 Initial commit: Complete threaded conversation system with inline replies
**Major Features Added:**
- **Inline Reply System**: Replace compose screen with inline reply boxes
- **Thread Navigation**: Parent/child navigation with jump functionality
- **Chain Flow UI**: Reply counts, expand/collapse animations, visual hierarchy
- **Enhanced Animations**: Smooth transitions, hover effects, micro-interactions

 **Frontend Changes:**
- **ThreadedCommentWidget**: Complete rewrite with animations and navigation
- **ThreadNode Model**: Added parent references and descendant counting
- **ThreadedConversationScreen**: Integrated navigation handlers
- **PostDetailScreen**: Replaced with threaded conversation view
- **ComposeScreen**: Added reply indicators and context
- **PostActions**: Fixed visibility checks for chain buttons

 **Backend Changes:**
- **API Route**: Added /posts/:id/thread endpoint
- **Post Repository**: Include allow_chain and visibility fields in feed
- **Thread Handler**: Support for fetching post chains

 **UI/UX Improvements:**
- **Reply Context**: Clear indication when replying to specific posts
- **Character Counting**: 500 character limit with live counter
- **Visual Hierarchy**: Depth-based indentation and styling
- **Smooth Animations**: SizeTransition, FadeTransition, hover states
- **Chain Navigation**: Parent/child buttons with visual feedback

 **Technical Enhancements:**
- **Animation Controllers**: Proper lifecycle management
- **State Management**: Clean separation of concerns
- **Navigation Callbacks**: Reusable navigation system
- **Error Handling**: Graceful fallbacks and user feedback

This creates a Reddit-style threaded conversation experience with smooth
animations, inline replies, and intuitive navigation between posts in a chain.
2026-01-30 07:40:19 -06:00

32 lines
1.1 KiB
Dart

/// Converts an ISO 3166-1 alpha-2 country code to a flag emoji.
///
/// Uses Unicode Regional Indicator Symbols to create flag emojis.
/// Each letter A-Z maps to a regional indicator symbol (U+1F1E6 to U+1F1FF).
/// Combining two regional indicators creates a flag emoji.
///
/// Example: 'US' -> 🇺🇸, 'GB' -> 🇬🇧, 'CA' -> 🇨🇦
///
/// Returns null if the country code is invalid or null.
String? getCountryFlag(String? countryCode) {
if (countryCode == null || countryCode.length != 2) {
return null;
}
final code = countryCode.toUpperCase();
// Validate that both characters are A-Z
if (!RegExp(r'^[A-Z]{2}$').hasMatch(code)) {
return null;
}
// Convert each letter to its regional indicator symbol
// 'A' = 65 in ASCII, Regional Indicator A = 0x1F1E6
// Offset = 0x1F1E6 - 65 = 127397
const int regionalIndicatorOffset = 0x1F1E6 - 65;
final firstChar = code.codeUnitAt(0) + regionalIndicatorOffset;
final secondChar = code.codeUnitAt(1) + regionalIndicatorOffset;
return String.fromCharCodes([firstChar, secondChar]);
}