From 310e05545f18301a72f750be98cd7dd5fc8db5a0 Mon Sep 17 00:00:00 2001
From: LD-Reborn <lucretia.dietz@gmx.de>
Date: Sat, 25 Oct 2025 22:15:08 +0200
Subject: [PATCH] Implemented users update button in frontend

---
 src/Controllers/UsersController.cs |  96 ++++----
 src/Helpers/UsersHelper.cs         |  44 ++++
 src/Models/UserModels.cs           |  12 +-
 src/Models/UsersRequestModels.cs   |  14 +-
 src/Models/UsersResponseModels.cs  |  13 ++
 src/Views/Home/Users.cshtml        | 355 ++++++++++++++++++++++++++---
 6 files changed, 458 insertions(+), 76 deletions(-)
 create mode 100644 src/Helpers/UsersHelper.cs
 create mode 100644 src/Models/UsersResponseModels.cs

diff --git a/src/Controllers/UsersController.cs b/src/Controllers/UsersController.cs
index 96cb3b4..ac43bd4 100644
--- a/src/Controllers/UsersController.cs
+++ b/src/Controllers/UsersController.cs
@@ -1,4 +1,3 @@
-// Controllers/UsersController.cs
 using Berufsschule_HAM.Services;
 using Microsoft.AspNetCore.Mvc;
 using Novell.Directory.Ldap;
@@ -8,6 +7,7 @@ using System.Security.Cryptography;
 using System.Text;
 using Microsoft.AspNetCore.Authorization;
 using System.Text.Json;
+using System.Buffers.Text;
 
 [Authorize(Roles = "CanManageUsers")]
 [Route("[controller]")]
@@ -66,7 +66,7 @@ public class UsersController : Controller
         try
         {
             jpegPhoto ??= Convert.ToBase64String(System.IO.File.ReadAllBytes("wwwroot/user_default.jpeg")); // TODO: cleanup - make this a config setting
-            uid ??= sn.ToLower() + cn.ToLower();
+            uid ??= UsersHelper.CreateUsername(cn, sn);
             title ??= "";
             description ??= "{}";
             if (!userPassword.StartsWith('{'))
@@ -98,53 +98,67 @@ public class UsersController : Controller
     }
 
     [HttpPost("Update")]
-    public async Task<bool> Update([FromBody] UsersModifyRequestModel requestModel)
+    public async Task<UsersUpdateRequestModel> Update([FromBody] UsersModifyRequestModel requestModel)
     {
         if (requestModel is null)
         {
             _logger.LogError("Unable to update a user because the UsersModifyRequestModel is null");
-            return false;
+            return new() { Success = false };
         }
-        string uid = requestModel.uid;
-        UserModel? user = null;
-        if (requestModel.Cn is not null)
+        try
         {
-            await _ldap.UpdateUser(uid, "cn", requestModel.Cn);
-            user ??= await _ldap.GetUserByUidAsync(uid);
-            string newUid = user.Sn?.ToLower() + requestModel.Cn.ToLower();
-            await _ldap.UpdateUser(uid, "uid", newUid);
-            uid = newUid;
-        }
-        if (requestModel.Sn is not null)
+            string uid = requestModel.Uid;
+            UserModel? user = null;
+            if (requestModel.NewUid is not null && requestModel.NewUid.Length > 0)
+            {
+                await _ldap.UpdateUser(uid, "uid", requestModel.NewUid);
+                uid = requestModel.NewUid;
+            }
+            if (requestModel.Title is not null)
+            {
+                await _ldap.UpdateUser(uid, "title", requestModel.Title);
+            }
+            if (requestModel.Description is not null)
+            {
+                await _ldap.UpdateUser(uid, "description", JsonSerializer.Serialize(requestModel.Description));
+            }
+            if (requestModel.JpegPhoto is not null && requestModel.JpegPhoto.Length > 0)
+            {
+                await _ldap.UpdateUser(uid, "jpegPhoto", requestModel.JpegPhoto);
+            }
+            if (requestModel.UserPassword is not null && requestModel.UserPassword.Length > 0)
+            {
+                await _ldap.UpdateUser(uid, "userPassword", "{SHA256}" + Convert.ToBase64String(SHA256.HashData(Encoding.UTF8.GetBytes(requestModel.UserPassword))));
+            }
+
+            string newUid = uid;
+            if (requestModel.Cn is not null)
+            {
+                await _ldap.UpdateUser(uid, "cn", requestModel.Cn);
+                user ??= await _ldap.GetUserByUidAsync(uid);
+                newUid = UsersHelper.CreateUsername(requestModel.Cn, user.Sn ?? "");
+                
+            }
+            if (requestModel.Sn is not null)
+            {
+                await _ldap.UpdateUser(uid, "sn", requestModel.Sn);
+                user ??= await _ldap.GetUserByUidAsync(uid);
+                newUid = UsersHelper.CreateUsername(user.Cn ?? "", requestModel.Sn);
+            }
+            if (newUid.Length == 0)
+            {
+                throw new Exception("Username cannot be empty");
+            }
+            if (newUid != uid)
+            {
+                await _ldap.UpdateUser(uid, "uid", newUid);
+                uid = newUid;
+            }
+            return new() { Success = true, NewUid = uid };
+        } catch (Exception ex)
         {
-            await _ldap.UpdateUser(uid, "sn", requestModel.Sn);
-            user ??= await _ldap.GetUserByUidAsync(uid);
-            string newUid = requestModel.Sn.ToLower() + user.Cn?.ToLower();
-            await _ldap.UpdateUser(uid, "uid", newUid);
-            uid = newUid;
+            return new() { Success = false, Exception = ex.Message };
         }
-        if (requestModel.NewUid is not null)
-        {
-            await _ldap.UpdateUser(uid, "uid", requestModel.NewUid);
-            uid = requestModel.NewUid;
-        }
-        if (requestModel.Title is not null)
-        {
-            await _ldap.UpdateUser(uid, "title", requestModel.Title);
-        }
-        if (requestModel.Description is not null)
-        {
-            await _ldap.UpdateUser(uid, "description", requestModel.Description);
-        }
-        if (requestModel.JpegPhoto is not null)
-        {
-            await _ldap.UpdateUser(uid, "jpegPhoto", requestModel.JpegPhoto);
-        }
-        if (requestModel.UserPassword is not null)
-        {
-            await _ldap.UpdateUser(uid, "userPassword", requestModel.UserPassword);
-        }
-        return true;
     }
 
     [HttpPost("AddGroup")]
diff --git a/src/Helpers/UsersHelper.cs b/src/Helpers/UsersHelper.cs
new file mode 100644
index 0000000..7f16c4e
--- /dev/null
+++ b/src/Helpers/UsersHelper.cs
@@ -0,0 +1,44 @@
+using System.Globalization;
+using System.Text;
+using System.Text.RegularExpressions;
+namespace Berufsschule_HAM.Helpers;
+
+public static partial class UsersHelper
+{
+    public static string CreateUsername(string givenName, string surname)
+    {
+        if (string.IsNullOrWhiteSpace(givenName) || string.IsNullOrWhiteSpace(surname))
+            throw new ArgumentException("Given name and surname must not be empty.");
+
+        string combined = (surname + givenName).ToLowerInvariant();
+
+        // Normalize to decompose accents (e.g., é -> e +  ́)
+        string normalized = combined.Normalize(NormalizationForm.FormD);
+
+        // Remove diacritics
+        var sb = new StringBuilder();
+        foreach (var c in normalized)
+        {
+            var category = CharUnicodeInfo.GetUnicodeCategory(c);
+            if (category != UnicodeCategory.NonSpacingMark)
+                sb.Append(c);
+        }
+
+        string cleaned = sb.ToString();
+
+        // Replace German ligatures etc.
+        cleaned = cleaned
+            .Replace("ß", "ss")
+            .Replace("æ", "ae")
+            .Replace("œ", "oe")
+            .Replace("ø", "o");
+
+        // Remove everything not a-z
+        cleaned = AtoZ().Replace(cleaned, "");
+
+        return cleaned;
+    }
+
+    [GeneratedRegex("[^a-z]")]
+    private static partial Regex AtoZ();
+}
\ No newline at end of file
diff --git a/src/Models/UserModels.cs b/src/Models/UserModels.cs
index 7fe6616..52cd777 100644
--- a/src/Models/UserModels.cs
+++ b/src/Models/UserModels.cs
@@ -1,4 +1,5 @@
 using System.Text.Json;
+using System.Text.Json.Serialization;
 
 namespace Berufsschule_HAM.Models;
 
@@ -26,17 +27,24 @@ public class UserModel
 
 public class UserDescription
 {
+    [JsonPropertyName("BirthDate")]
     public required string BirthDate { get; set; }
+    [JsonPropertyName("Address")]
     public required UserAddress Address { get; set; }
+    [JsonPropertyName("Workplace")]
     public required string Workplace { get; set; }
+    [JsonPropertyName("Groups")]
     public List<string>? Groups { get; set; }
 }
 
 public class UserAddress
 {
+    [JsonPropertyName("City")]
     public string? City { get; set; }
+    [JsonPropertyName("Street")]
     public string? Street { get; set; }
-    public string? StreetNr { get; set; }
+    [JsonPropertyName("StreetNr")]
+    public int? StreetNr { get; set; }
 }
 
 public class UserAuthenticationResult
@@ -61,5 +69,5 @@ public class UserTableViewModel
     public required string Title { get; set; }
     public required string Name { get; set; }
     public required string Surname { get; set; }
-    public required string Workplace { get; set; }
+    public required UserDescription Description { get; set; }
 }
\ No newline at end of file
diff --git a/src/Models/UsersRequestModels.cs b/src/Models/UsersRequestModels.cs
index 0abfe5a..9b98e63 100644
--- a/src/Models/UsersRequestModels.cs
+++ b/src/Models/UsersRequestModels.cs
@@ -1,3 +1,5 @@
+using System.Text.Json.Serialization;
+
 namespace Berufsschule_HAM.Models;
 
 public class UsersIndexRequestModel
@@ -13,13 +15,21 @@ public class UsersIndexRequestModel
 
 public class UsersModifyRequestModel
 {
-    public required string uid { get; set; }
+    [JsonPropertyName("Uid")]
+    public required string Uid { get; set; }
+    [JsonPropertyName("NewUid")]
     public string? NewUid { get; set; } = null;
+    [JsonPropertyName("Cn")]
     public string? Cn { get; set; } = null;
+    [JsonPropertyName("Sn")]
     public string? Sn { get; set; } = null;
+    [JsonPropertyName("Title")]
     public string? Title { get; set; } = null;
-    public string? Description { get; set; } = null;
+    [JsonPropertyName("Description")]
+    public UserDescription? Description { get; set; } = null;
+    [JsonPropertyName("JpegPhoto")]
     public string? JpegPhoto { get; set; } = null;
+    [JsonPropertyName("UserPassword")]
     public string? UserPassword { get; set; } = null;
 }
 
diff --git a/src/Models/UsersResponseModels.cs b/src/Models/UsersResponseModels.cs
new file mode 100644
index 0000000..0df701d
--- /dev/null
+++ b/src/Models/UsersResponseModels.cs
@@ -0,0 +1,13 @@
+using System.Text.Json.Serialization;
+
+namespace Berufsschule_HAM.Models;
+
+public class UsersUpdateRequestModel
+{
+    [JsonPropertyName("Success")]
+    public required bool Success { get; set; }
+    [JsonPropertyName("Exception")]
+    public string? Exception { get; set; }
+    [JsonPropertyName("NewUid")]
+    public string? NewUid { get; set; }
+}
\ No newline at end of file
diff --git a/src/Views/Home/Users.cshtml b/src/Views/Home/Users.cshtml
index c526b36..84e5392 100644
--- a/src/Views/Home/Users.cshtml
+++ b/src/Views/Home/Users.cshtml
@@ -1,6 +1,8 @@
 @using Microsoft.AspNetCore.Mvc.Localization
 @using Berufsschule_HAM.Models
 @using System.Buffers.Text
+@using System.Text.Json;
+@using System.Text.Json.Serialization;
 @model UsersIndexViewModel
 @inject IViewLocalizer T
 @{
@@ -42,15 +44,29 @@
                     <td>@userTableViewModel.Title</td>
                     <td>@userTableViewModel.Name</td>
                     <td>@userTableViewModel.Surname</td>
-                    <td>@userTableViewModel.Workplace</td>
+                    <td>@userTableViewModel.Description.Workplace</td>
                     <td>
                         <div class="d-flex gap-2">
-                            <button class="btn btn-sm btn-primary">Update</button>
+                            <button class="btn btn-sm btn-warning"
+                                data-user-id="@userTableViewModel.Uid"
+                                data-user-title="@userTableViewModel.Title"
+                                data-user-name="@userTableViewModel.Name"
+                                data-user-surname="@userTableViewModel.Surname"
+                                data-user-workplace="@userTableViewModel.Description.Workplace"
+                                data-user-birthdate="@userTableViewModel.Description.BirthDate"
+                                data-user-address-city="@userTableViewModel.Description.Address.City"
+                                data-user-address-street="@userTableViewModel.Description.Address.Street"
+                                data-user-address-streetnr="@userTableViewModel.Description.Address.StreetNr"
+                                data-user-groups="@JsonSerializer.Serialize(userTableViewModel.Description.Groups)"
+                                data-bs-toggle="modal"
+                                data-bs-target="#updateModal">
+                                Update
+                            </button>
                             <button class="btn btn-sm btn-danger btn-delete" 
                                 data-user-id="@userTableViewModel.Uid"
                                 data-bs-toggle="modal"
                                 data-bs-target="#deleteModal">
-                                🗑️ Delete
+                                Delete
                             </button>
                         </div>
                     </td>
@@ -84,6 +100,34 @@
 </div>
 
 
+<script>
+    // Simple toast helper
+    function showToast(message, type) {
+        const toastContainer = document.getElementById('toastContainer') || createToastContainer();
+        const toast = document.createElement('div');
+        toast.className = `toast align-items-center text-white bg-${type} border-0`;
+        toast.role = 'alert';
+        toast.innerHTML = `
+            <div class="d-flex">
+                <div class="toast-body">${message}</div>
+                <button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast"></button>
+            </div>
+        `;
+        toastContainer.appendChild(toast);
+        const bsToast = new bootstrap.Toast(toast, { delay: 3000 });
+        bsToast.show();
+        toast.addEventListener('hidden.bs.toast', () => toast.remove());
+    }
+
+    function createToastContainer() {
+        const container = document.createElement('div');
+        container.id = 'toastContainer';
+        container.className = 'toast-container position-fixed bottom-0 end-0 p-3';
+        document.body.appendChild(container);
+        return container;
+    }
+</script>
+
 <script>
     document.addEventListener('DOMContentLoaded', () => {
         const deleteModal = document.getElementById('deleteModal');
@@ -115,8 +159,7 @@
                     headers: {
                         'Content-Type': 'application/json',
                         'Accept': 'application/json'
-                    }//,
-                    //body: JSON.stringify({ id: userId }) // Use this for Post requests with [FromBody] parameters like in /Groups/Update
+                    }
                 });
 
                 const result = await response.json();
@@ -140,31 +183,281 @@
                 showToast('Error contacting server', 'danger');
             }
         });
-
-        // Simple toast helper
-        function showToast(message, type) {
-            const toastContainer = document.getElementById('toastContainer') || createToastContainer();
-            const toast = document.createElement('div');
-            toast.className = `toast align-items-center text-white bg-${type} border-0`;
-            toast.role = 'alert';
-            toast.innerHTML = `
-                <div class="d-flex">
-                    <div class="toast-body">${message}</div>
-                    <button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast"></button>
-                </div>
-            `;
-            toastContainer.appendChild(toast);
-            const bsToast = new bootstrap.Toast(toast, { delay: 3000 });
-            bsToast.show();
-            toast.addEventListener('hidden.bs.toast', () => toast.remove());
-        }
-
-        function createToastContainer() {
-            const container = document.createElement('div');
-            container.id = 'toastContainer';
-            container.className = 'toast-container position-fixed bottom-0 end-0 p-3';
-            document.body.appendChild(container);
-            return container;
-        }
     });
 </script>
+
+<!-- User Update Modal -->
+<div class="modal fade" id="updateModal" tabindex="-1" aria-labelledby="updateModalLabel" aria-hidden="true">
+    <div class="modal-dialog modal-dialog-centered modal-lg">
+        <div class="modal-content">
+            <div class="modal-header bg-warning text-dark">
+                <h5 class="modal-title" id="updateModalLabel">Update User</h5>
+                <button type="button" class="btn-close btn-close-white" data-bs-dismiss="modal"></button>
+            </div>
+            <div class="modal-body">
+                <form id="updateForm">
+                    <input type="hidden" id="updateUid" name="Uid" />
+
+                    <div class="row g-3">
+                        <h6 class="fw-bold">Personal information</h6>
+                        <div class="col-md-6">
+                            <label class="form-label">Title</label>
+                            <input type="text" id="updateTitle" name="Title" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">Name</label>
+                            <input type="text" id="updateName" name="Cn" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">Surname</label>
+                            <input type="text" id="updateSurname" name="Sn" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">Birth date</label>
+                            <input type="text" id="updateBirthdate" name="Description.BirthDate" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">City</label>
+                            <input type="text" id="updateAddressCity" name="Description.Address.City" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">Street</label>
+                            <input type="text" id="updateAddressStreet" name="Description.Address.Street" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">Street Nr.</label>
+                            <input type="text" id="updateAddressStreetNr" name="Description.Address.StreetNr" class="form-control" />
+                        </div>
+                        <hr class="my-3">
+                        <h6 class="fw-bold">Workplace & account</h6>
+                        <div class="col-md-6">
+                            <label class="form-label">Workplace</label>
+                            <input type="text" id="updateWorkplace" name="Description.Workplace" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">Groups</label>
+                            <select id="updateGroups" name="Description.Groups" class="form-select" multiple></select>
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">New Password</label>
+                            <input type="password" id="updatePassword" name="UserPassword" class="form-control" />
+                        </div>
+                        <div class="col-md-6">
+                            <label class="form-label">Photo</label>
+                            <input type="file" id="updatePhotoFile" accept="image/*" class="form-control" />
+                            <input type="hidden" id="updateJpegPhoto" name="JpegPhoto" />
+                            <div class="mt-2 text-center">
+                                <img id="updatePhotoPreview" src="" alt="Preview" class="img-thumbnail" style="max-height: 150px; display: none;" />
+                            </div>
+                        </div>
+                    </div>
+                </form>
+            </div>
+            <div class="modal-footer">
+                <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Cancel</button>
+                <button type="submit" form="updateForm" class="btn btn-warning">Save changes</button>
+            </div>
+        </div>
+    </div>
+</div>
+
+<script>
+
+    function unflatten(obj) {
+        const result = {};
+        for (const [key, value] of Object.entries(obj)) {
+            const parts = key.split(".");
+            let current = result;
+            for (let i = 0; i < parts.length; i++) {
+                const part = parts[i];
+
+                if (i === parts.length - 1) {
+                    // Last part — assign value
+                    try {
+                        // Try to parse JSON strings like "[...]" if possible
+                        current[part] = JSON.parse(value);
+                    } catch {
+                        current[part] = value;
+                    }
+                } else {
+                    // Intermediate part — create object if needed
+                    current[part] = current[part] || {};
+                    current = current[part];
+                }
+            }
+        }
+
+        return result;
+    }
+
+    document.addEventListener('DOMContentLoaded', () => {
+        // --- Update user modal ---
+        const updateModal = document.getElementById('updateModal');
+        const updateForm = document.getElementById('updateForm');
+        let updateButton = null;
+        
+        updateModal.addEventListener('show.bs.modal', event => {
+            updateButton = event.relatedTarget;
+            const userId = updateButton.getAttribute('data-user-id');
+            const title = updateButton.getAttribute('data-user-title');
+            const name = updateButton.getAttribute('data-user-name');
+            const surname = updateButton.getAttribute('data-user-surname');
+            const workplace = updateButton.getAttribute('data-user-workplace');
+            const birthdate = updateButton.getAttribute('data-user-birthdate');
+            const addressCity = updateButton.getAttribute('data-user-address-city');
+            const addressStreet = updateButton.getAttribute('data-user-address-street');
+            const addressStreetNr = updateButton.getAttribute('data-user-address-streetnr');
+
+            // Fill form fields
+            updateForm.querySelector('#updateUid').value = userId;
+            updateForm.querySelector('#updateTitle').value = title || '';
+            updateForm.querySelector('#updateName').value = name || '';
+            updateForm.querySelector('#updateSurname').value = surname || '';
+            updateForm.querySelector('#updateWorkplace').value = workplace || '';
+            updateForm.querySelector('#updateBirthdate').value = birthdate || '';
+            updateForm.querySelector('#updateAddressCity').value = addressCity || '';
+            updateForm.querySelector('#updateAddressStreet').value = addressStreet || '';
+            updateForm.querySelector('#updateAddressStreetNr').value = addressStreetNr || '';
+            updateForm.querySelector('#updatePassword').value = '';
+            updateForm.querySelector('#updateJpegPhoto').value = '';
+        });
+
+        updateForm.addEventListener('submit', async e => {
+            e.preventDefault();
+            var dataFromEntries = Object.fromEntries(new FormData(updateForm).entries());
+            var data = unflatten(dataFromEntries);
+            data.Description.Groups = Array.from(updateForm.querySelector('#updateGroups').selectedOptions).map(option => option.value);
+            try {
+                const response = await fetch('/Users/Update', {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/json', 'Accept': 'application/json' },
+                    body: JSON.stringify(data)
+                });
+
+                const result = await response.json();
+                if (result.Success) {
+                    // Close modal
+                    bootstrap.Modal.getInstance(updateModal).hide();
+
+                    // Update table row
+                    const row = updateButton.closest('tr');
+                    row.querySelector('td:nth-child(2)').textContent = result.NewUid || '';
+                    row.querySelector('td:nth-child(3)').textContent = data.Title || '';
+                    row.querySelector('td:nth-child(4)').textContent = data.Cn || '';
+                    row.querySelector('td:nth-child(5)').textContent = data.Sn || '';
+                    row.querySelector('td:nth-child(6)').textContent = data.Description?.Workplace || '';
+                    // Update button data attributes, so the next edit uses the new data
+                    updateButton.setAttribute('data-user-id', result.NewUid || '');
+                    updateButton.setAttribute('data-user-title', data.Title || '');
+                    updateButton.setAttribute('data-user-name', data.Cn || '');
+                    updateButton.setAttribute('data-user-surname', data.Sn || '');
+                    updateButton.setAttribute('data-user-workplace', data.Description?.Workplace || '');
+                    updateButton.setAttribute('data-user-groups', JSON.stringify(data.Description?.Groups || []));
+                    
+                    if (data.JpegPhoto && data.JpegPhoto.length > 0) {
+                        const img = row.querySelector('td:first-child img');
+                        if (img) {
+                            img.src = `data:image/jpeg;base64,${data.JpegPhoto}`;
+                            img.classList.add('border', 'border-success'); // optional visual feedback
+                            setTimeout(() => img.classList.remove('border', 'border-success'), 1000);
+                        }
+                    }
+                    updateForm.reset();
+                    document.getElementById('updatePhotoPreview').style.display = "none";
+                    showToast('User updated successfully', 'success');
+                } else {
+                    showToast(`${result.Exception || 'Update failed'}`, 'danger');
+                }
+            } catch (err) {
+                console.error(err);
+                showToast('Error updating user', 'danger');
+            }
+        });
+    });
+
+    // Group select drop-down
+    document.addEventListener('DOMContentLoaded', () => {
+        const updateModal = document.getElementById('updateModal');
+        const updateForm = document.getElementById('updateForm');
+        const updateGroupsSelect = document.getElementById('updateGroups');
+        let updateButton = null;
+
+        updateModal.addEventListener('show.bs.modal', async event => {
+            updateButton = event.relatedTarget;
+
+            const userId = updateButton.getAttribute('data-user-id');
+            const title = updateButton.getAttribute('data-user-title');
+            const name = updateButton.getAttribute('data-user-name');
+            const surname = updateButton.getAttribute('data-user-surname');
+            const workplace = updateButton.getAttribute('data-user-workplace');
+            const groups = JSON.parse(updateButton.getAttribute('data-user-groups'));
+
+            // Fill basic fields
+            updateForm.querySelector('#updateUid').value = userId;
+            updateForm.querySelector('#updateTitle').value = title || '';
+            updateForm.querySelector('#updateName').value = name || '';
+            updateForm.querySelector('#updateSurname').value = surname || '';
+            updateForm.querySelector('#updateWorkplace').value = workplace || '';
+            updateForm.querySelector('#updatePassword').value = '';
+            updateForm.querySelector('#updateJpegPhoto').value = '';
+
+            // Fetch available groups
+            await populateGroupsDropdown(updateGroupsSelect, groups);
+
+            // Fetch user's existing groups (you need to provide them via data-attribute or fetch)
+            const existingGroups = updateButton.getAttribute('data-user-groups');
+            if (existingGroups) {
+                const selectedGroups = existingGroups.split(',');
+                Array.from(updateGroupsSelect.options).forEach(opt => {
+                    opt.selected = selectedGroups.includes(opt.value);
+                });
+            }
+        });
+
+        async function populateGroupsDropdown(selectElement, preselectedGroups) {
+            try {
+                const res = await fetch('/Groups/Get');
+                const json = await res.json();
+                if (!json.success) {
+                    console.warn('Failed to fetch groups', json);
+                    return;
+                }
+                selectElement.innerHTML = '';
+                json.GroupModels.forEach(group => {
+                    const opt = document.createElement('option');
+                    opt.value = group.Cn;
+                    opt.textContent = group.DisplayName || group.Cn;
+                    selectElement.appendChild(opt);
+                    if (preselectedGroups != null && preselectedGroups.includes(group.Cn)) {
+                        setTimeout(() => {
+                            opt.selected = true;
+                        }, 200);
+                    }
+                });
+            } catch (err) {
+                console.error('Error fetching groups', err);
+            }
+        }
+    });
+
+    document.addEventListener('DOMContentLoaded', () => {
+        const photoInput = document.getElementById('updatePhotoFile');
+        const photoPreview = document.getElementById('updatePhotoPreview');
+        const photoHidden = document.getElementById('updateJpegPhoto');
+
+        photoInput.addEventListener('change', () => {
+            const file = photoInput.files[0];
+            if (!file) return;
+
+            const reader = new FileReader();
+            reader.onload = e => {
+                const base64 = e.target.result.split(',')[1]; // strip data:image/jpeg;base64,
+                photoHidden.value = base64;
+                photoPreview.src = e.target.result;
+                photoPreview.style.display = 'block';
+            };
+            reader.readAsDataURL(file);
+        });
+    });
+
+</script>