import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import '../../core/services/chit_group_service.dart';
import '../../core/models/chit_group.dart';
import '../../core/models/user.dart';

class MemberSelectionDialog extends StatefulWidget {
  final ChitGroup group;
  
  const MemberSelectionDialog({
    super.key,
    required this.group,
  });

  @override
  State<MemberSelectionDialog> createState() => _MemberSelectionDialogState();
}

class _MemberSelectionDialogState extends State<MemberSelectionDialog> {
  final ChitGroupService _service = ChitGroupService.to;
  final TextEditingController _searchController = TextEditingController();
  
  List<User> _allUsers = [];
  List<User> _filteredUsers = [];
  List<User> _selectedUsers = [];
  bool _isLoading = false;
  bool _isAdding = false;
  String _searchQuery = '';

  @override
  void initState() {
    super.initState();
    // Load available users directly (no need to load existing members separately)
    _loadAllUsers();
  }

  @override
  void dispose() {
    _searchController.dispose();
    super.dispose();
  }


  Future<void> _loadAllUsers() async {
    try {
      // Use the enhanced API that filters by group ID
      final users = await _service.getAvailableUsersForGroup(widget.group.id);
      
      print('Total available users for group ${widget.group.id}: ${users.length}');
      print('User IDs: ${users.map((u) => u.id).toList()}');
      
      setState(() {
        _allUsers = users;
        _filteredUsers = users;
      });
      
    } catch (e) {
      print('Error loading available users: $e');
      setState(() {
        _allUsers = [];
        _filteredUsers = [];
      });
      
      // Show error message instead of sample data
      Get.snackbar(
        'Error',
        'Failed to load available users. Please try again.',
        backgroundColor: Colors.red.shade100,
        colorText: Colors.red.shade800,
        snackPosition: SnackPosition.TOP,
      );
    } finally {
      setState(() => _isLoading = false);
    }
  }


  void _filterUsers(String query) {
    setState(() {
      _searchQuery = query;
      if (query.isEmpty) {
        _filteredUsers = _allUsers;
      } else {
        _filteredUsers = _allUsers.where((user) {
          return user.fullName.toLowerCase().contains(query.toLowerCase()) ||
                 user.mobileNumber.contains(query);
        }).toList();
      }
    });
  }


  void _toggleUserSelection(User user) {
    setState(() {
      if (_selectedUsers.contains(user)) {
        _selectedUsers.remove(user);
      } else {
        _selectedUsers.add(user);
      }
    });
  }

  Future<void> _addSelectedUsersToGroup() async {
    if (_selectedUsers.isEmpty) {
      Get.snackbar(
        'Error',
        'Please select at least one user',
        backgroundColor: Colors.orange.shade100,
        colorText: Colors.orange.shade800,
        snackPosition: SnackPosition.TOP,
      );
      return;
    }

    setState(() => _isAdding = true);
    
    try {
      int successCount = 0;
      int errorCount = 0;
      
      for (final user in _selectedUsers) {
        final success = await _service.addMemberToGroup(widget.group.id, {
          'mobile_number': user.mobileNumber,
        });
        
        if (success) {
          successCount++;
        } else {
          errorCount++;
        }
      }
      
      Navigator.of(context).pop(); // Close dialog
      
      if (successCount > 0) {
        Get.snackbar(
          'Success',
          '$successCount user(s) added to chitfund successfully!',
          backgroundColor: Colors.green.shade100,
          colorText: Colors.green.shade800,
          snackPosition: SnackPosition.TOP,
        );
      }
      
      if (errorCount > 0) {
        Get.snackbar(
          'Warning',
          '$errorCount user(s) could not be added (may already be members)',
          backgroundColor: Colors.orange.shade100,
          colorText: Colors.orange.shade800,
          snackPosition: SnackPosition.TOP,
        );
      }
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to add members. Please try again.',
        backgroundColor: Colors.red.shade100,
        colorText: Colors.red.shade800,
        snackPosition: SnackPosition.TOP,
      );
    } finally {
      setState(() => _isAdding = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Dialog(
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16.r)),
      child: Container(
        width: 0.85.sw,
        height: 0.8.sh,
        child: Column(
          children: [
            // Header
            Container(
              padding: EdgeInsets.all(12.w),
              decoration: BoxDecoration(
                color: Colors.blue.shade600,
                borderRadius: BorderRadius.only(
                  topLeft: Radius.circular(16.r),
                  topRight: Radius.circular(16.r),
                ),
              ),
              child: Row(
                children: [
                  Icon(
                    Icons.people_alt,
                    color: Colors.white,
                    size: 24.w,
                  ),
                  SizedBox(width: 12.w),
                  Expanded(
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Text(
                          'Select Members',
                          style: TextStyle(
                            color: Colors.white,
                            fontSize: 16.sp,
                            fontWeight: FontWeight.w600,
                          ),
                        ),
                        Text(
                          widget.group.name,
                          style: TextStyle(
                            color: Colors.white.withOpacity(0.8),
                            fontSize: 12.sp,
                          ),
                        ),
                      ],
                    ),
                  ),
                  IconButton(
                    onPressed: () => Navigator.of(context).pop(),
                    icon: const Icon(Icons.close, color: Colors.white),
                    padding: EdgeInsets.zero,
                    constraints: const BoxConstraints(),
                  ),
                ],
              ),
            ),

            // Chitfund Info
            Container(
              padding: EdgeInsets.symmetric(horizontal: 8.w, vertical: 6.h),
              color: Colors.blue.shade50,
              child: Row(
                children: [
                  Expanded(
                    child: _buildInfoItem('Monthly', '₹${widget.group.monthlyInstallment.toStringAsFixed(0)}'),
                  ),
                  Expanded(
                    child: _buildInfoItem('Members', '${widget.group.currentMemberCount}/${widget.group.maxMembers}'),
                  ),
                  Expanded(
                    child: _buildInfoItem('Available', '${widget.group.maxMembers - widget.group.currentMemberCount}'),
                  ),
                ],
              ),
            ),

            // Search and Selection Controls
            Container(
              padding: EdgeInsets.all(8.w),
              child: Column(
                children: [
                  // Search Bar
                  TextField(
                    controller: _searchController,
                    decoration: InputDecoration(
                      hintText: 'Search users...',
                      prefixIcon: const Icon(Icons.search),
                      suffixIcon: _isLoading
                          ? SizedBox(
                              width: 20.w,
                              height: 20.w,
                              child: const CircularProgressIndicator(strokeWidth: 2),
                            )
                          : IconButton(
                              icon: const Icon(Icons.refresh),
                              onPressed: () {
                                print('Manual refresh triggered');
                                _loadAllUsers();
                              },
                              tooltip: 'Refresh members',
                            ),
                      border: OutlineInputBorder(
                        borderRadius: BorderRadius.circular(8.r),
                      ),
                      contentPadding: EdgeInsets.symmetric(horizontal: 12.w, vertical: 12.h),
                    ),
                    onChanged: _filterUsers,
                  ),
                  SizedBox(height: 6.h),
                  
                  
                  // Selection Summary
                  Row(
                    children: [
                      Expanded(
                        child: Text(
                          '${_filteredUsers.length} users available',
                          style: TextStyle(
                            fontSize: 14.sp,
                            color: Colors.grey.shade600,
                          ),
                        ),
                      ),
                      if (_selectedUsers.isNotEmpty)
                        Container(
                          padding: EdgeInsets.symmetric(horizontal: 12.w, vertical: 4.h),
                          decoration: BoxDecoration(
                            color: Colors.blue.shade100,
                            borderRadius: BorderRadius.circular(12.r),
                          ),
                          child: Text(
                            '${_selectedUsers.length} selected',
                            style: TextStyle(
                              fontSize: 12.sp,
                              fontWeight: FontWeight.w600,
                              color: Colors.blue.shade700,
                            ),
                          ),
                        ),
                    ],
                  ),
                ],
              ),
            ),

            // Users List
            Flexible(
              child: _isLoading && _allUsers.isEmpty
                  ? const Center(child: CircularProgressIndicator())
                  : _filteredUsers.isEmpty
                      ? Center(
                          child: Column(
                            mainAxisAlignment: MainAxisAlignment.center,
                            children: [
                              Icon(
                                Icons.people_outline,
                                size: 64.w,
                                color: Colors.grey.shade400,
                              ),
                              SizedBox(height: 16.h),
                              Text(
                                _searchQuery.isEmpty
                                    ? 'No users found'
                                    : 'No users match your search',
                                style: TextStyle(
                                  fontSize: 16.sp,
                                  color: Colors.grey.shade600,
                                ),
                              ),
                              if (_searchQuery.isNotEmpty) ...[
                                SizedBox(height: 8.h),
                                TextButton(
                                  onPressed: () {
                                    _searchController.clear();
                                    _filterUsers('');
                                  },
                                  child: const Text('Clear search'),
                                ),
                              ],
                            ],
                          ),
                        )
                      : ListView.builder(
                          padding: EdgeInsets.symmetric(horizontal: 12.w),
                          itemCount: _filteredUsers.length,
                          itemBuilder: (context, index) {
                            final user = _filteredUsers[index];
                            final isSelected = _selectedUsers.contains(user);
                            return _buildUserCard(user, isSelected);
                          },
                        ),
            ),

            // Footer
            Container(
              padding: EdgeInsets.all(8.w),
              decoration: BoxDecoration(
                color: Colors.grey.shade50,
                borderRadius: BorderRadius.only(
                  bottomLeft: Radius.circular(16.r),
                  bottomRight: Radius.circular(16.r),
                ),
              ),
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  // Status text
                  Text(
                    _selectedUsers.isEmpty
                        ? 'Select users to add'
                        : 'Ready to add ${_selectedUsers.length} user(s)',
                    style: TextStyle(
                      fontSize: 12.sp,
                      color: Colors.grey.shade600,
                    ),
                    textAlign: TextAlign.center,
                  ),
                  SizedBox(height: 8.h),
                  // Action buttons
                  Row(
                    children: [
                      Expanded(
                        child: OutlinedButton(
                          onPressed: () => Navigator.of(context).pop(),
                          style: OutlinedButton.styleFrom(
                            padding: EdgeInsets.symmetric(vertical: 12.h),
                          ),
                          child: const Text('Cancel'),
                        ),
                      ),
                      SizedBox(width: 8.w),
                      Expanded(
                        child: ElevatedButton(
                          onPressed: _isAdding || _selectedUsers.isEmpty ? null : _addSelectedUsersToGroup,
                          style: ElevatedButton.styleFrom(
                            backgroundColor: Colors.blue.shade600,
                            foregroundColor: Colors.white,
                            padding: EdgeInsets.symmetric(vertical: 12.h),
                          ),
                          child: _isAdding
                              ? SizedBox(
                                  width: 16.w,
                                  height: 16.w,
                                  child: const CircularProgressIndicator(
                                    strokeWidth: 2,
                                    valueColor: AlwaysStoppedAnimation<Color>(Colors.white),
                                  ),
                                )
                              : Text('Add ${_selectedUsers.length} Member(s)'),
                        ),
                      ),
                    ],
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildInfoItem(String label, String value) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.center,
      children: [
        Text(
          label,
          style: TextStyle(
            fontSize: 10.sp,
            color: Colors.blue.shade600,
            fontWeight: FontWeight.w500,
          ),
          textAlign: TextAlign.center,
        ),
        SizedBox(height: 2.h),
        Text(
          value,
          style: TextStyle(
            fontSize: 12.sp,
            fontWeight: FontWeight.w600,
            color: Colors.blue.shade800,
          ),
          textAlign: TextAlign.center,
        ),
      ],
    );
  }

  Widget _buildUserCard(User user, bool isSelected) {
    return Card(
      margin: EdgeInsets.only(bottom: 4.h),
      elevation: isSelected ? 4 : 1,
      color: isSelected ? Colors.blue.shade50 : Colors.white,
      child: ListTile(
        dense: true,
        contentPadding: EdgeInsets.symmetric(horizontal: 12.w, vertical: 4.h),
        leading: CircleAvatar(
          radius: 16.r,
          backgroundColor: isSelected ? Colors.blue.shade600 : Colors.blue.shade100,
          child: Text(
            user.fullName.isNotEmpty ? user.fullName[0].toUpperCase() : '?',
            style: TextStyle(
              color: isSelected ? Colors.white : Colors.blue.shade700,
              fontWeight: FontWeight.w600,
              fontSize: 12.sp,
            ),
          ),
        ),
        title: Text(
          user.fullName,
          style: TextStyle(
            fontSize: 14.sp,
            fontWeight: FontWeight.w600,
            color: isSelected ? Colors.blue.shade800 : Colors.grey.shade800,
          ),
        ),
        subtitle: Text(
          user.mobileNumber,
          style: TextStyle(
            fontSize: 12.sp,
            color: isSelected ? Colors.blue.shade600 : Colors.grey.shade600,
          ),
        ),
        trailing: Checkbox(
          value: isSelected,
          onChanged: (bool? value) => _toggleUserSelection(user),
          activeColor: Colors.blue.shade600,
          materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
        ),
        onTap: () => _toggleUserSelection(user),
      ),
    );
  }

  String _formatDate(DateTime date) {
    return '${date.day}/${date.month}/${date.year}';
  }
}