// punch_status_banner.dart
//
// Top-of-connection-page banner that shows whether the current session is a
// P2P direct connection (NAT punch succeeded) or a relay fallback (NAT punch
// failed, going through the user's 21117 server). User-facing copy makes the
// implications clear:
//
//   - P2P: 绿色横幅 + ⚡ icon: "P2P 直连成功 — 走的是两台机器之间的网络，可放心传文件"
//   - Relay: 橙色横幅 + ⚠ icon: "中继模式 — 视频/控制走服务器 21117 中转，请勿传大文件"
//
// The status comes from ConnectionType.direct, which the Rust core sets
// when the connection is established (see src/client/io_loop.rs:184 —
// set_connection_type(secure, direct, stream_type)).
//
// The banner is reactive: it subscribes to the Rx<String> so it updates
// automatically if the connection type changes (e.g. after a re-connect).
//
// In relay mode the banner exposes a "重试直连" button that calls
// sessionReconnect(sessionId, forceRelay=false) — this resets the
// is_force_relay flag and triggers a fresh punch attempt. Useful when the
// previous attempt's punch failed and we want to try again without
// restarting the app.

import 'package:flutter/material.dart';
import 'package:get/get.dart';

import '../../common/shared_state.dart';
import '../../models/model.dart';

class PunchStatusBanner extends StatelessWidget {
  final String peerId;
  final SessionID? sessionId;
  const PunchStatusBanner(
      {super.key, required this.peerId, this.sessionId});

  @override
  Widget build(BuildContext context) {
    return Obx(() {
      final ct = ConnectionTypeState.find(peerId);
      if (!ct.isValid()) {
        // Not connected yet — show nothing
        return const SizedBox.shrink();
      }
      final isDirect = ct.direct.value == ConnectionType.strDirect;
      if (isDirect) {
        return _Banner(
          color: const Color(0xFFE7F5EA), // light green
          iconColor: const Color(0xFF1E8E3E),
          icon: Icons.bolt,
          text: 'P2P 直连成功 — 走的是两台机器之间的网络，可放心传文件',
          sessionId: sessionId,
        );
      } else {
        return _Banner(
          color: const Color(0xFFFFF3E0), // light orange
          iconColor: const Color(0xFFE65100),
          icon: Icons.warning_amber_rounded,
          text: '中继模式 — 视频/控制走服务器 21117 中转，请勿传大文件',
          sessionId: sessionId,
        );
      }
    });
  }
}

class _Banner extends StatelessWidget {
  final Color color;
  final Color iconColor;
  final IconData icon;
  final String text;
  final SessionID? sessionId;
  const _Banner({
    required this.color,
    required this.iconColor,
    required this.icon,
    required this.text,
    this.sessionId,
  });

  @override
  Widget build(BuildContext context) {
    return Material(
      color: color,
      elevation: 2,
      child: SafeArea(
        bottom: false,
        child: Padding(
          padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
          child: Row(
            mainAxisSize: MainAxisSize.min,
            children: [
              Icon(icon, color: iconColor, size: 18),
              const SizedBox(width: 8),
              Flexible(
                child: Text(
                  text,
                  style: TextStyle(
                    color: iconColor,
                    fontSize: 13,
                    fontWeight: FontWeight.w500,
                  ),
                ),
              ),
              const SizedBox(width: 8),
              TextButton.icon(
                onPressed:
                    sessionId == null ? null : () => _retryDirect(sessionId!),
                icon: const Icon(Icons.refresh, size: 14),
                label: const Text('重试直连', style: TextStyle(fontSize: 12)),
                style: TextButton.styleFrom(
                  foregroundColor: iconColor,
                  padding:
                      const EdgeInsets.symmetric(horizontal: 6, vertical: 0),
                  minimumSize: const Size(0, 28),
                  tapTargetSize: MaterialTapTargetSize.shrinkWrap,
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  void _retryDirect(SessionID sessionId) {
    // Resets is_force_relay and triggers a fresh punch attempt.
    bind.sessionReconnect(sessionId: sessionId, forceRelay: false);
  }
}