docs(README.md): update error handling section and improve API endpoint descriptions

docs(userscript/README.md): enhance configuration instructions and clarify connection testing
feat(userscript/simpleguardhome-404-checker.user.js): add connection testing and notification features for unblocking domains

README.md

@@ -183,7 +183,6 @@ Documentation is available at:
 - ReDoc: `http://localhost:8000/api/redoc` - Alternative documentation UI
 - OpenAPI Schema: `http://localhost:8000/api/openapi.json` - Raw OpenAPI specification
 
-### API Endpoints
 ### API Endpoints
 
 All endpoints follow the official AdGuard Home API specification:
@@ -251,24 +250,23 @@ simpleguardhome/
 
 ## Error Handling
 
-The application implements comprehensive error handling for all endpoints:
+The application implements comprehensive error handling according to endpoint:
 
-- 400 Bad Request
-  - Invalid domain format
-  - Missing required parameters
-  - Invalid whitelist rule format
-- 500 Internal Server Error
-  - Failed to add domain to whitelist
-  - Other internal processing errors
-- 502 Bad Gateway
-  - AdGuard Home API errors
-  - Invalid API responses
-- 503 Service Unavailable
-  - AdGuard Home service unreachable
-  - Connection timeouts
-  - Network errors
+GET /control/filtering/check_host:
+- 400: Invalid domain format or missing name parameter
+- 503: AdGuard Home service unavailable
 
-All errors return an ErrorResponse object with a descriptive message.
+GET /control/filtering/unblock_host:
+- 400: Invalid domain format or missing name parameter
+- 500: Failed to unblock domain
+- 503: AdGuard Home service unavailable
+
+POST /control/filtering/set_rules:
+- 400: Invalid rule format or missing rules
+- 500: Failed to update rules
+- 503: AdGuard Home service unavailable
+
+All endpoints return an ErrorResponse model with a descriptive message.
 
 ## Response Models
 

userscript/README.md

@@ -6,7 +6,8 @@ A Tampermonkey userscript that detects 404 responses while browsing and automati
 
 - Automatically detects 404 responses from both fetch and XMLHttpRequest calls
 - Checks failed domains against your AdGuard Home instance
-- Shows notifications for blocked domains with unblock option
+- Shows notifications for blocked domains with one-click unblock button
+- Directly unblocks domains using SimpleGuardHome API
 - Configurable AdGuard Home instance settings
 - Caches results to minimize API calls
 - Error handling with configuration shortcuts
@@ -20,14 +21,28 @@ A Tampermonkey userscript that detects 404 responses while browsing and automati
 
 ## Configuration
 
+### Initial Setup
 1. Click on the Tampermonkey icon in your browser
-2. Select "Configure SimpleGuardHome Instance" under the script's menu
-3. Enter your AdGuard Home host (e.g., `http://localhost`)
-4. Enter your AdGuard Home port (default: 3000)
+2. Select "⚙️ Configure SimpleGuardHome" under the script's menu
+3. Review your current settings (if any)
+4. Enter new host and port settings
+5. Connection test will be performed automatically
+   - Success: Settings are saved immediately
+   - Failure: Option to save anyway or retry
+
+### Menu Options
+- "⚙️ Configure SimpleGuardHome" - Open configuration dialog
+- "🔄 Test Connection" - Test current settings
 
 ### Default Settings
 - Host: `http://localhost`
-- Port: `3000`
+- Port: `8000` (SimpleGuardHome default port)
+
+### Connection Testing
+- Automatic testing when saving new settings
+- Manual testing available through menu
+- Clear notifications of test results
+- Option to save settings even if test fails
 
 ## How It Works
 
@@ -35,8 +50,10 @@ A Tampermonkey userscript that detects 404 responses while browsing and automati
 2. When a 404 response is detected:
    - Extracts the domain from the failed URL
    - Checks if the domain is blocked by AdGuard Home
-   - Shows a notification if the domain is blocked
-   - Provides a quick "Unblock" button to open SimpleGuardHome
+   - Shows a notification with status if domain is blocked
+   - Provides a one-click "Unblock Domain" button
+   - Directly unblocks domain when button is clicked
+   - Shows success/error notification after unblock attempt
 
 3. Error handling:
    - Connection issues show a notification with configuration options
@@ -54,10 +71,11 @@ A Tampermonkey userscript that detects 404 responses while browsing and automati
 ### Cache System
 - Domain check results are cached for 1 hour
 - Cache includes:
-  - Block status
-  - Blocking reason
-  - Applied rules
+  - Block status (true/false)
   - Timestamp
+- Cache is updated when:
+  - Domain is checked (status: "not blocked", "blocked")
+  - Domain is unblocked (status: "already unblocked", "has been unblocked")
 
 ### Error Handling
 - Connection failures

userscript/simpleguardhome-404-checker.user.js

@@ -19,7 +19,7 @@
     // Default configuration
     const DEFAULT_CONFIG = {
         host: 'http://localhost',
-        port: 8000
+        port: 8000  // SimpleGuardHome runs on port 8000 by default
     };
 
     // Get current configuration
@@ -30,27 +30,144 @@
         };
     }
 
-    // Show configuration dialog
-    function showConfigDialog() {
-        const config = getConfig();
-        const host = prompt('Enter SimpleGuardHome host (e.g. http://localhost):', config.host);
-        if (host === null) return;
-
-        const port = prompt('Enter SimpleGuardHome port:', config.port);
-        if (port === null) return;
-
-        GM_setValue('host', host);
-        GM_setValue('port', parseInt(port, 10) || DEFAULT_CONFIG.port);
-
-        alert('Configuration saved! The new settings will be used for future checks.');
+    // Test SimpleGuardHome connection
+    async function testConnection(host, port) {
+        try {
+            const response = await new Promise((resolve, reject) => {
+                GM_xmlhttpRequest({
+                    method: 'GET',
+                    url: `${host}:${port}/health`,
+                    headers: {'Accept': 'application/json'},
+                    onload: resolve,
+                    onerror: reject
+                });
+            });
+            return response.status === 200;
+        } catch (error) {
+            return false;
+        }
     }
 
-    // Register configuration menu command
-    GM_registerMenuCommand('Configure SimpleGuardHome Instance', showConfigDialog);
+    // Show configuration dialog
+    async function showConfigDialog() {
+        const config = getConfig();
+        const currentSettings = `Current Settings:
+- Host: ${config.host}
+- Port: ${config.port}
+
+Enter new settings or cancel to keep current.`;
+
+        const host = prompt(currentSettings + '\n\nEnter SimpleGuardHome host (e.g. http://localhost):', config.host);
+        if (host === null) return;
+
+        const port = prompt('Enter SimpleGuardHome port (default: 8000):', config.port);
+        if (port === null) return;
+
+        const newPort = parseInt(port, 10) || DEFAULT_CONFIG.port;
+
+        // Test connection with new settings
+        const success = await testConnection(host, newPort);
+        if (success) {
+            GM_setValue('host', host);
+            GM_setValue('port', newPort);
+            createNotification('SimpleGuardHome configuration saved and connection tested successfully!');
+        } else {
+            const save = confirm('Could not connect to SimpleGuardHome with these settings. Save anyway?');
+            if (save) {
+                GM_setValue('host', host);
+                GM_setValue('port', newPort);
+                createNotification('Configuration saved, but connection test failed. Please verify your settings.');
+            }
+        }
+    }
+
+    // Register configuration menu commands
+    GM_registerMenuCommand('⚙️ Configure SimpleGuardHome', showConfigDialog);
+    GM_registerMenuCommand('🔄 Test Connection', async () => {
+        const config = getConfig();
+        const success = await testConnection(config.host, config.port);
+        createNotification(success ?
+            'Successfully connected to SimpleGuardHome!' :
+            'Could not connect to SimpleGuardHome. Please check your settings.');
+    });
 
     // Store check results to avoid repeated API calls
     const checkedDomains = new Map();
 
+    // Create notification container
+    function createNotification(message, showUnblockButton = false, domain = '') {
+        const notif = document.createElement('div');
+        notif.style.cssText = `
+            position: fixed;
+            bottom: 20px;
+            right: 20px;
+            background: #333;
+            color: white;
+            padding: 15px;
+            border-radius: 5px;
+            box-shadow: 0 2px 5px rgba(0,0,0,0.2);
+            z-index: 9999;
+            font-family: sans-serif;
+            max-width: 300px;
+        `;
+        
+        const messageDiv = document.createElement('div');
+        messageDiv.textContent = message;
+        notif.appendChild(messageDiv);
+
+        if (showUnblockButton) {
+            const button = document.createElement('button');
+            button.textContent = 'Unblock Domain';
+            button.style.cssText = `
+                margin-top: 10px;
+                padding: 5px 10px;
+                background: #007bff;
+                color: white;
+                border: none;
+                border-radius: 3px;
+                cursor: pointer;
+            `;
+            button.onclick = () => unblockDomain(domain);
+            notif.appendChild(button);
+        }
+
+        document.body.appendChild(notif);
+        setTimeout(() => notif.remove(), 10000); // Remove after 10 seconds
+    }
+
+    // Unblock a domain
+    async function unblockDomain(domain) {
+        const config = getConfig();
+        const apiUrl = `${config.host}:${config.port}/control/filtering/unblock_host?name=${encodeURIComponent(domain)}`;
+
+        GM_xmlhttpRequest({
+            method: 'GET',
+            url: apiUrl,
+            headers: {'Accept': 'application/json'},
+            onload: function(response) {
+                try {
+                    const data = JSON.parse(response.responseText);
+                    createNotification(data.message);
+                    
+                    // Update cache if successful
+                    if (data.message.includes('unblocked')) {
+                        checkedDomains.set(domain, {
+                            isBlocked: false,
+                            timestamp: Date.now()
+                        });
+                    }
+                } catch (error) {
+                    console.error('SimpleGuardHome unblock error:', error);
+                    createNotification('Failed to unblock domain. Please try again.');
+                }
+            },
+            onerror: function(error) {
+                console.error('SimpleGuardHome API error:', error);
+                createNotification('Error connecting to SimpleGuardHome. Please check your settings.');
+            }
+        });
+    }
+
     // Check if domain is blocked by AdGuard Home
     async function checkDomain(domain) {
         // Skip if already checked recently
@@ -80,9 +197,13 @@
                             timestamp: Date.now()
                         });
 
-                        // If blocked, redirect to SimpleGuardHome interface
+                        // If blocked, show notification with unblock option
                         if (isBlocked) {
-                            window.location.href = apiUrl;
+                            createNotification(
+                                `Domain ${domain} is blocked by AdGuard Home.`,
+                                true,
+                                domain
+                            );
                         }
                     } catch (error) {
                         console.error('SimpleGuardHome parsing error:', error);