implemented anonymous user authentification with browser identification number from cookies

migrations/005_browser_id.sql

@@ -19,7 +19,7 @@ CREATE INDEX idx_votes_browser ON votes(browser_id);
 
 -- Drops old Constraint voter_name based
 ALTER TABLE votes
-    DROP CONSTRAINT IF EXISTS votes_contribution_id_voter_name_key;
+    DROP CONSTRAINT IF EXISTS votes_unique_per_voter;
 
 -- Creates new Constraint browser_id based
 ALTER TABLE votes

public/api/contributions.php

@@ -126,6 +126,23 @@ function handle_read($input) {
         'features' => $features
     ];
 
+    // Includes User's Votes for persistent Vote Display
+    // Returns which Contributions the current Browser has voted on
+    $browser_id = $input['browser_id'] ?? '';
+    if ($browser_id !== '') {
+        $stmt = $pdo->prepare("
+            SELECT contribution_id, vote_type 
+            FROM votes 
+            WHERE browser_id = :bid
+        ");
+        $stmt->execute([':bid' => $browser_id]);
+        $user_votes = [];
+        foreach ($stmt->fetchAll() as $v) {
+            $user_votes[$v['contribution_id']] = $v['vote_type'];
+        }
+        $featureCollection['user_votes'] = $user_votes;
+    }
+
     json_response($featureCollection);
 }
 
@@ -162,10 +179,10 @@ function handle_create($input) {
     try {
         $stmt = $pdo->prepare("
             INSERT INTO contributions 
-                (municipality_id, geom, geom_type, category, title, description, author_name)
+                (municipality_id, geom, geom_type, category, title, description, author_name, browser_id)
             VALUES 
                 (:mid, ST_SetSRID(ST_GeomFromGeoJSON(:geom), 4326), :geom_type, 
-                 :category, :title, :description, :author_name)
+                 :category, :title, :description, :author_name, :browser_id)
         ");
 
         $stmt->execute([
@@ -175,7 +192,8 @@ function handle_create($input) {
             ':category'    => $input['category'],
             ':title'       => $input['title'],
             ':description' => $input['description'] ?? '',
-            ':author_name' => $input['author_name']
+            ':author_name' => $input['author_name'],
+            ':browser_id'  => $input['browser_id'] ?? null
         ]);
 
         json_response([
@@ -320,11 +338,16 @@ function handle_vote($input) {
     // Prepared SQL Statement
     try {
         // Checks if Voter already voted on this Contribution
+        $browser_id = $input['browser_id'] ?? '';
+        if (empty($browser_id)) {
+            error_response('Browser ID required for Voting.');
+        }
+
         $stmt = $pdo->prepare("
             SELECT vote_id, vote_type FROM votes
-            WHERE contribution_id = :cid AND voter_name = :voter
+            WHERE contribution_id = :cid AND browser_id = :bid
         ");
-        $stmt->execute([':cid' => $input['contribution_id'], ':voter' => $input['voter_name']]);
+        $stmt->execute([':cid' => $input['contribution_id'], ':bid' => $browser_id]);
         $existing = $stmt->fetch();
 
         if ($existing) {
@@ -339,27 +362,29 @@ function handle_vote($input) {
                 $stmt->execute([':vid' => $existing['vote_id']]);
 
                 $stmt = $pdo->prepare("
-                    INSERT INTO votes (contribution_id, voter_name, vote_type)
+                    INSERT INTO votes (contribution_id, voter_name, vote_type, browser_id)
-                    VALUES (:cid, :voter, :vtype)
+                    VALUES (:cid, :voter, :vtype, :bid)
                 ");
                 $stmt->execute([
                     ':cid'   => $input['contribution_id'],
                     ':voter' => $input['voter_name'],
-                    ':vtype' => $input['vote_type']
+                    ':vtype' => $input['vote_type'],
+                    ':bid'   => $browser_id
                 ]);
                 json_response(['message' => 'Vote changed.', 'action' => 'changed'], 200);
             }
         } else {
             // No existing Vote — Inserts Vote
             $stmt = $pdo->prepare("
-                INSERT INTO votes (contribution_id, voter_name, vote_type)
+                    INSERT INTO votes (contribution_id, voter_name, vote_type, browser_id)
-                VALUES (:cid, :voter, :vtype)
+                    VALUES (:cid, :voter, :vtype, :bid)
-            ");
+                ");
-            $stmt->execute([
+                $stmt->execute([
-                ':cid'   => $input['contribution_id'],
+                    ':cid'   => $input['contribution_id'],
-                ':voter' => $input['voter_name'],
+                    ':voter' => $input['voter_name'],
-                ':vtype' => $input['vote_type']
+                    ':vtype' => $input['vote_type'],
-            ]);
+                    ':bid'   => $browser_id
+                ]);
             json_response(['message' => 'Vote recorded.', 'action' => 'created'], 201);
         }
 

public/index.php

@@ -5,18 +5,8 @@
 // Renders Leaflet Map Interface including Leaflet Plugins
 // =====================================================================
 
-// Reads Environment Configfile
-$envFile = __DIR__ . '/../../.env';
-if (file_exists($envFile)) {
-    $lines = file($envFile, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
-    foreach ($lines as $line) {
-        if (strpos(trim($line), '#') === 0) continue;
-        list($key, $value) = array_map('trim', explode('=', $line, 2));
-        putenv("$key=$value");
-    }
-}
-
 require_once __DIR__ . '/api/db.php';
+require_once __DIR__ . '/api/auth.php';
 
 // -----------------------------------------------------------------
 // Loads Municipality Configuration
@@ -122,6 +112,8 @@ $news_items = $stmt->fetchAll();
 
         <!-- Mobile Hamburger Menu -->
         <button class="header-menu-toggle" onclick="toggleMobileNav()">
+            <i class="fa-solid fa-bars"></i>
+        </button>
     </header>
 
 
@@ -370,6 +362,9 @@ $news_items = $stmt->fetchAll();
 
         // Category Definitions from Database
         const CATEGORIES = <?= json_encode(get_categories(), JSON_UNESCAPED_UNICODE) ?>;
+
+        // Admin Status from PHP Session
+        const IS_ADMIN = <?= (function_exists('is_admin') && is_admin()) ? 'true' : 'false' ?>;
     </script>
 
     <!-- Application Logic -->

public/js/app.js

@@ -16,9 +16,26 @@
 // API Endpoint as relative Path
 const API_URL = 'api/contributions.php';
 
-// Current User Name, set via Login Modal, stored in sessionStorage
+// Username set via Login Modal stored in sessionStorage
 let currentUser = sessionStorage.getItem('webgis_user') || '';
 
+// Browser Identification Number for anonymous User Identification stored as Cookie
+let browserId = getBrowserId();
+
+function getBrowserId() {
+    let id = document.cookie.replace(/(?:(?:^|.*;\s*)webgis_browser_id\s*=\s*([^;]*).*$)|^.*$/, '$1');
+    if (!id) {
+        id = 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function (c) {
+            const r = Math.random() * 16 | 0;
+            return (c === 'x' ? r : (r & 0x3 | 0x8)).toString(16);
+        });
+        // Cookie Expiration in one Year
+        document.cookie = 'webgis_browser_id=' + id + ';path=/;max-age=31536000;SameSite=Lax';
+    }
+    return id;
+}
+
+
 // Application State
 let map;                                      // Leaflet Map Instance
 let sidebar;                                  // Sidebar Instance
@@ -290,9 +307,15 @@ function apiCall(data, callback) {
         });
 }
 
+
 // Loads all Contributions from API and displays Contributions on Map
 function loadContributions() {
-    apiCall({ action: 'read', municipality_id: MUNICIPALITY.id }, function (data) {
+    const readParams = { action: 'read', municipality_id: MUNICIPALITY.id };
+
+    // Sends Browser ID for persistent Vote Display
+    readParams.browser_id = browserId;
+
+    apiCall(readParams, function (data) {
         if (data.error) {
             console.error('Load Error:', data.error);
             return;
@@ -300,6 +323,14 @@ function loadContributions() {
 
         contributionsData = data.features || [];
 
+        // Restores Vote Highlights from API Response
+        if (data.user_votes) {
+            userVotes = {};
+            for (const key in data.user_votes) {
+                userVotes[key] = data.user_votes[key];
+            }
+        }
+
         // Removes existing Layer if present
         if (contributionsLayer) {
             map.removeLayer(contributionsLayer);
@@ -384,7 +415,7 @@ function buildPopupHtml(feature) {
                     '<i class="fa-solid fa-thumbs-down"></i> <span id="dislikes-' + props.contribution_id + '">' + props.dislikes_count + '</span>' +
                 '</button>' +
             '</div>' +
-            (currentUser === props.author_name ?
+            (props.browser_id === browserId || (typeof IS_ADMIN !== 'undefined' && IS_ADMIN) ?
                 '<div class="popup-detail-actions">' +
                     '<button class="btn btn-primary" onclick="editContribution(' + props.contribution_id + ')"><i class="fa-solid fa-pen"></i> Bearbeiten</button>' +
                     '<button class="btn btn-danger" onclick="deleteContribution(' + props.contribution_id + ')"><i class="fa-solid fa-trash"></i> Löschen</button>' +
@@ -441,7 +472,8 @@ function submitCreate() {
         description: description,
         geom: geom,
         geom_type: geomType,
-        author_name: currentUser
+        author_name: currentUser,
+        browser_id: browserId
     }, function (response) {
         if (response.error) {
             Swal.fire('Fehler', response.error, 'error');
@@ -570,7 +602,8 @@ function voteContribution(contributionId, voteType) {
         action: 'vote',
         contribution_id: contributionId,
         voter_name: currentUser,
-        vote_type: voteType
+        vote_type: voteType,
+        browser_id: browserId
     }, function (response) {
         if (response.error) {
             return;