Bump version to 4.0.1 with Web UI improvements

- Update version to 4.0.1 across constants.py, __init__.py, pyproject.toml, README
- Refactor channel key UI from radio buttons to select dropdown
- Add LED indicator and key capsule CSS styles
- Reorganize encode/decode forms: RSA key section moved up, PIN + Channel in row
- Streamline channel key JavaScript for dropdown-based selection

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

README.md

@@ -5,7 +5,7 @@ A secure steganography system for hiding encrypted messages in images using hybr
 ![Python](https://img.shields.io/badge/Python-3.10--3.12-blue)
 ![License](https://img.shields.io/badge/License-MIT-green)
 ![Security](https://img.shields.io/badge/Security-AES--256--GCM-red)
-![Version](https://img.shields.io/badge/Version-4.0.0-purple)
+![Version](https://img.shields.io/badge/Version-4.0.1-purple)
 
 ## Features
 

frontends/web/static/js/stegasoo.js

@@ -751,51 +751,35 @@ const Stegasoo = {
     /**
      * Initialize channel key UI for encode/decode pages
      * @param {Object} config - Configuration object
-     * @param {string} config.radioName - Name of radio buttons (default: 'channel_key')
+     * @param {string} config.selectId - ID of channel select dropdown
      * @param {string} config.customInputId - ID of custom key input container
      * @param {string} config.keyInputId - ID of key input field
      * @param {string} config.generateBtnId - ID of generate button (optional)
-     * @param {string} config.customRadioId - ID of custom radio button
-     * @param {string[]} config.cardIds - Array of card/label IDs for active class toggling
      */
     initChannelKey(config = {}) {
-        const radioName = config.radioName || 'channel_key';
+        const selectId = config.selectId || 'channelSelect';
         const customInputId = config.customInputId || 'channelCustomInput';
         const keyInputId = config.keyInputId || 'channelKeyInput';
         const generateBtnId = config.generateBtnId;
-        const customRadioId = config.customRadioId || 'channelCustom';
-        const cardIds = config.cardIds || [];
 
-        const radios = document.querySelectorAll(`input[name="${radioName}"]`);
+        const select = document.getElementById(selectId);
         const customInput = document.getElementById(customInputId);
         const keyInput = document.getElementById(keyInputId);
         const generateBtn = generateBtnId ? document.getElementById(generateBtnId) : null;
-        const customRadio = document.getElementById(customRadioId);
-        
-        // Toggle active class on mode-btn cards
-        const updateActiveState = () => {
-            radios.forEach(radio => {
-                const card = radio.closest('.mode-btn');
-                if (card) {
-                    card.classList.toggle('active', radio.checked);
-                }
-            });
-        };
 
         // Show/hide custom input based on selection
-        radios.forEach(radio => {
+        const updateVisibility = () => {
-            radio.addEventListener('change', () => {
+            const isCustom = select?.value === 'custom';
-                updateActiveState();
-                const isCustom = customRadio?.checked;
             customInput?.classList.toggle('d-none', !isCustom);
             if (isCustom && keyInput) {
                 keyInput.focus();
             }
-            });
+        };
-        });
+
+        select?.addEventListener('change', updateVisibility);
 
         // Initial state
-        updateActiveState();
+        updateVisibility();
 
         // Format and validate key input
         keyInput?.addEventListener('input', () => {
@@ -814,22 +798,22 @@ const Stegasoo = {
     /**
      * Handle form submission with channel key validation
      * @param {HTMLFormElement} form - Form element
-     * @param {string} customRadioId - ID of custom radio button
+     * @param {string} selectId - ID of channel select dropdown
      * @param {string} keyInputId - ID of key input field
      * @returns {boolean} True if valid, false to prevent submission
      */
-    validateChannelKeyOnSubmit(form, customRadioId, keyInputId) {
+    validateChannelKeyOnSubmit(form, selectId, keyInputId) {
-        const customRadio = document.getElementById(customRadioId);
+        const select = document.getElementById(selectId);
         const keyInput = document.getElementById(keyInputId);
 
-        if (customRadio?.checked && keyInput) {
+        if (select?.value === 'custom' && keyInput) {
             if (!this.validateChannelKey(keyInput.value)) {
                 keyInput.classList.add('is-invalid');
                 keyInput.focus();
                 return false;
             }
-            // Set the radio value to the actual key for form submission
+            // Set the select value to the actual key for form submission
-            customRadio.value = keyInput.value;
+            select.value = keyInput.value;
         }
         return true;
     },
@@ -880,20 +864,19 @@ const Stegasoo = {
         this.initCollapseChevrons();
         this.initPassphraseFontResize();
         
-        // Channel key (v4.0.0) - uses mode-btn style
+        // Channel key (v4.0.0) - uses select dropdown
         this.initChannelKey({
+            selectId: 'channelSelect',
             customInputId: 'channelCustomInput',
             keyInputId: 'channelKeyInput',
-            generateBtnId: 'channelKeyGenerate',
+            generateBtnId: 'channelKeyGenerate'
-            customRadioId: 'channelCustom',
-            cardIds: ['channelAutoCard', 'channelPublicCard', 'channelCustomCard']
         });
 
         // Form submission with channel key validation
         const form = document.getElementById('encodeForm');
         const btn = document.getElementById('encodeBtn');
         form?.addEventListener('submit', (e) => {
-            if (!this.validateChannelKeyOnSubmit(form, 'channelCustom', 'channelKeyInput')) {
+            if (!this.validateChannelKeyOnSubmit(form, 'channelSelect', 'channelKeyInput')) {
                 e.preventDefault();
                 return false;
             }
@@ -913,19 +896,18 @@ const Stegasoo = {
         this.initCollapseChevrons();
         this.initPassphraseFontResize();
         
-        // Channel key (v4.0.0) - uses mode-btn style
+        // Channel key (v4.0.0) - uses select dropdown
         this.initChannelKey({
+            selectId: 'channelSelectDec',
             customInputId: 'channelCustomInputDec',
-            keyInputId: 'channelKeyInputDec',
+            keyInputId: 'channelKeyInputDec'
-            customRadioId: 'channelCustomDec',
-            cardIds: ['channelAutoCardDec', 'channelPublicCardDec', 'channelCustomCardDec']
         });
 
         // Form submission with channel key validation and mode display
         const form = document.getElementById('decodeForm');
         const btn = document.getElementById('decodeBtn');
         form?.addEventListener('submit', (e) => {
-            if (!this.validateChannelKeyOnSubmit(form, 'channelCustomDec', 'channelKeyInputDec')) {
+            if (!this.validateChannelKeyOnSubmit(form, 'channelSelectDec', 'channelKeyInputDec')) {
                 e.preventDefault();
                 return false;
             }

frontends/web/static/style.css

@@ -1323,3 +1323,58 @@ footer {
     font-weight: 600;
     font-size: 0.5rem;
 }
+
+/* ----------------------------------------------------------------------------
+   LED Indicator
+   ---------------------------------------------------------------------------- */
+.led-indicator {
+    display: inline-block;
+    width: 6px;
+    height: 6px;
+    border-radius: 50%;
+    vertical-align: middle;
+}
+
+.led-yellow {
+    background: #fbbf24;
+    box-shadow: 0 0 3px #fbbf24, 0 0 6px rgba(251, 191, 36, 0.4);
+}
+
+.led-green {
+    background: #22c55e;
+    box-shadow: 0 0 3px #22c55e, 0 0 6px rgba(34, 197, 94, 0.4);
+}
+
+.led-red {
+    background: #ef4444;
+    box-shadow: 0 0 3px #ef4444, 0 0 6px rgba(239, 68, 68, 0.4);
+}
+
+/* LED Badge backgrounds */
+.led-badge-yellow {
+    background: rgba(251, 191, 36, 0.2);
+    border: 1px solid rgba(251, 191, 36, 0.4);
+    color: #fbbf24;
+}
+
+.led-badge-green {
+    background: rgba(34, 197, 94, 0.2);
+    border: 1px solid rgba(34, 197, 94, 0.4);
+    color: #22c55e;
+}
+
+.led-badge-red {
+    background: rgba(239, 68, 68, 0.2);
+    border: 1px solid rgba(239, 68, 68, 0.4);
+    color: #ef4444;
+}
+
+/* Key capsule container */
+.key-capsule {
+    display: inline-flex;
+    align-items: center;
+    border: 1px dashed rgba(255, 255, 255, 0.3);
+    border-radius: 0.375rem;
+    padding: 0.35rem 0.75rem;
+    background: rgba(0, 0, 0, 0.1);
+}

frontends/web/templates/decode.html

@@ -264,21 +264,7 @@
                         <span class="text-warning small">(provide same factors used during encoding)</span>
                     </h6>
                     
-                    <div class="row">
+                    <div class="mb-3">
-                        <div class="col-md-4 mb-3">
-                          <div class="security-box">
-                            <label class="form-label"><i class="bi bi-123 me-1"></i> PIN</label>
-                            <div class="input-group pin-input-container">
-                                <input type="password" name="pin" class="form-control" id="pinInput" placeholder="••••••" maxlength="9" style="max-width: 180px;">
-                                <button class="btn btn-outline-secondary" type="button" data-toggle-password="pinInput">
-                                    <i class="bi bi-eye"></i>
-                                </button>
-                            </div>
-                            <div class="form-text">If PIN was used during encoding</div>
-                          </div>
-                        </div>
-                        
-                        <div class="col-md-8 mb-3">
                       <div class="security-box">
                         <label class="form-label">
                             <i class="bi bi-file-earmark-lock me-1"></i> RSA Key
@@ -338,53 +324,52 @@
                         </div>
                       </div>
                     </div>
+
+                    <!-- PIN + Channel Row -->
+                    <div class="row">
+                        <div class="col-md-4 mb-3">
+                          <div class="security-box h-100">
+                            <label class="form-label"><i class="bi bi-123 me-1"></i> PIN</label>
+                            <div class="input-group pin-input-container">
+                                <input type="password" name="pin" class="form-control" id="pinInput" placeholder="••••••" maxlength="9" style="max-width: 180px;">
+                                <button class="btn btn-outline-secondary" type="button" data-toggle-password="pinInput">
+                                    <i class="bi bi-eye"></i>
+                                </button>
+                            </div>
+                            <div class="form-text">If PIN was used during encoding</div>
+                          </div>
                         </div>
 
-                    <!-- ================================================================
+                        <div class="col-md-8 mb-3">
-                         CHANNEL KEY (v4.0.0) - Deployment/Group Isolation
+                          <div class="security-box h-100">
-                         ================================================================ -->
-                    <div class="mb-4">
-                      <div class="security-box">
                             <label class="form-label">
                                 <i class="bi bi-broadcast me-1"></i> Channel
                                 <span class="badge bg-info ms-1">v4.0</span>
+                                <a href="/about#channel-keys" class="text-muted ms-1" title="Learn about channels"><i class="bi bi-info-circle"></i></a>
                             </label>
 
-                        <div class="d-flex gap-2">
+                            <select class="form-select" name="channel_key" id="channelSelectDec">
-                            <!-- Auto Mode -->
+                                <option value="auto" selected>Auto{% if channel_configured %} (Server Key){% endif %}</option>
-                            <label class="mode-btn flex-fill {% if channel_configured %}active{% endif %}" id="channelAutoCardDec" for="channelAutoDec">
+                                <option value="none">Public</option>
-                                <input class="form-check-input" type="radio" name="channel_key" id="channelAutoDec" value="auto" checked>
+                                <option value="custom">Custom</option>
-                                <i class="bi bi-gear-fill {% if channel_configured %}text-success{% else %}text-secondary{% endif %} ms-2"></i>
+                            </select>
-                                <span class="ms-2"><strong>Auto</strong> <span class="text-muted d-none d-sm-inline">· {% if channel_configured %}Server Key{% else %}Public{% endif %}</span></span>
-                            </label>
-                            
-                            <!-- Public Mode -->
-                            <label class="mode-btn flex-fill" id="channelPublicCardDec" for="channelPublicDec">
-                                <input class="form-check-input" type="radio" name="channel_key" id="channelPublicDec" value="none">
-                                <i class="bi bi-globe text-info ms-2"></i>
-                                <span class="ms-2"><strong>Public</strong> <span class="text-muted d-none d-sm-inline">· No key</span></span>
-                            </label>
-                            
-                            <!-- Custom Key -->
-                            <label class="mode-btn flex-fill" id="channelCustomCardDec" for="channelCustomDec">
-                                <input class="form-check-input" type="radio" name="channel_key" id="channelCustomDec" value="custom">
-                                <i class="bi bi-key-fill text-warning ms-2"></i>
-                                <span class="ms-2"><strong>Custom</strong></span>
-                            </label>
-                        </div>
 
                             <!-- Server channel indicator (compact) -->
                             {% if channel_configured %}
                             <div class="small text-success mt-2">
                                 <i class="bi bi-shield-lock me-1"></i>
-                            Server: <code>{{ channel_fingerprint }}</code>
+                                Server: <code>{{ channel_fingerprint[:4] }}-••••-···-••••-{{ channel_fingerprint[-4:] }}</code>
                             </div>
                             {% endif %}
+                          </div>
+                        </div>
+                    </div>
 
-                        <!-- Custom key input -->
+                    <!-- Custom Channel Key Input (shown when Custom selected) -->
-                        <div class="mt-2 d-none" id="channelCustomInputDec">
+                    <div class="mb-4 d-none" id="channelCustomInputDec">
-                            <div class="input-group input-group-sm">
+                        <div class="security-box">
-                                <span class="input-group-text"><i class="bi bi-key"></i></span>
+                            <label class="form-label"><i class="bi bi-key me-1"></i> Custom Channel Key</label>
+                            <div class="input-group">
                                 <input type="text" name="channel_key_custom" class="form-control font-monospace"
                                        placeholder="XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX"
                                        pattern="[A-Za-z0-9]{4}(-[A-Za-z0-9]{4}){7}"
@@ -392,7 +377,6 @@
                             </div>
                         </div>
                     </div>
-                    </div>
                     
                     <!-- ================================================================
                          ADVANCED OPTIONS (v3.0) - Extraction Mode

frontends/web/templates/encode.html

@@ -331,21 +331,7 @@
                         <span class="text-warning small">(provide at least one: PIN or RSA Key)</span>
                     </h6>
                     
-                    <div class="row">
+                    <div class="mb-3">
-                        <div class="col-md-4 mb-3">
-                          <div class="security-box">
-                            <label class="form-label"><i class="bi bi-123 me-1"></i> PIN</label>
-                            <div class="input-group pin-input-container">
-                              <input type="password" name="pin" class="form-control" id="pinInput" placeholder="••••••" maxlength="9" style="max-width: 180px;">
-                              <button class="btn btn-outline-secondary" type="button" data-toggle-password="pinInput">
-                                <i class="bi bi-eye"></i>
-                              </button>
-                            </div>
-                            <div class="form-text">Static 6-9 digit PIN</div>
-                          </div>
-                        </div>
-                        
-                        <div class="col-md-8 mb-3">
                       <div class="security-box">
                         <label class="form-label">
                             <i class="bi bi-file-earmark-lock me-1"></i> RSA Key
@@ -405,53 +391,52 @@
                         </div>
                       </div>
                     </div>
+
+                    <!-- PIN + Channel Row -->
+                    <div class="row">
+                        <div class="col-md-4 mb-3">
+                          <div class="security-box h-100">
+                            <label class="form-label"><i class="bi bi-123 me-1"></i> PIN</label>
+                            <div class="input-group pin-input-container">
+                              <input type="password" name="pin" class="form-control" id="pinInput" placeholder="••••••" maxlength="9" style="max-width: 180px;">
+                              <button class="btn btn-outline-secondary" type="button" data-toggle-password="pinInput">
+                                <i class="bi bi-eye"></i>
+                              </button>
+                            </div>
+                            <div class="form-text">Static 6-9 digit PIN</div>
+                          </div>
                         </div>
 
-                    <!-- ================================================================
+                        <div class="col-md-8 mb-3">
-                         CHANNEL KEY (v4.0.0) - Deployment/Group Isolation
+                          <div class="security-box h-100">
-                         ================================================================ -->
-                    <div class="mb-4">
-                      <div class="security-box">
                             <label class="form-label">
                                 <i class="bi bi-broadcast me-1"></i> Channel
                                 <span class="badge bg-info ms-1">v4.0</span>
+                                <a href="/about#channel-keys" class="text-muted ms-1" title="Learn about channels"><i class="bi bi-info-circle"></i></a>
                             </label>
 
-                        <div class="d-flex gap-2">
+                            <select class="form-select" name="channel_key" id="channelSelect">
-                            <!-- Auto Mode -->
+                                <option value="auto" selected>Auto{% if channel_configured %} (Server Key){% endif %}</option>
-                            <label class="mode-btn flex-fill {% if channel_configured %}active{% endif %}" id="channelAutoCard" for="channelAuto">
+                                <option value="none">Public</option>
-                                <input class="form-check-input" type="radio" name="channel_key" id="channelAuto" value="auto" checked>
+                                <option value="custom">Custom</option>
-                                <i class="bi bi-gear-fill {% if channel_configured %}text-success{% else %}text-secondary{% endif %} ms-2"></i>
+                            </select>
-                                <span class="ms-2"><strong>Auto</strong> <span class="text-muted d-none d-sm-inline">· {% if channel_configured %}Server Key{% else %}Public{% endif %}</span></span>
-                            </label>
-                            
-                            <!-- Public Mode -->
-                            <label class="mode-btn flex-fill" id="channelPublicCard" for="channelPublic">
-                                <input class="form-check-input" type="radio" name="channel_key" id="channelPublic" value="none">
-                                <i class="bi bi-globe text-info ms-2"></i>
-                                <span class="ms-2"><strong>Public</strong> <span class="text-muted d-none d-sm-inline">· No key</span></span>
-                            </label>
-                            
-                            <!-- Custom Key -->
-                            <label class="mode-btn flex-fill" id="channelCustomCard" for="channelCustom">
-                                <input class="form-check-input" type="radio" name="channel_key" id="channelCustom" value="custom">
-                                <i class="bi bi-key-fill text-warning ms-2"></i>
-                                <span class="ms-2"><strong>Custom</strong></span>
-                            </label>
-                        </div>
 
                             <!-- Server channel indicator (compact) -->
                             {% if channel_configured %}
                             <div class="small text-success mt-2" id="channelServerInfo">
                                 <i class="bi bi-shield-lock me-1"></i>
-                            Server: <code>{{ channel_fingerprint }}</code>
+                                Server: <code>{{ channel_fingerprint[:4] }}-••••-···-••••-{{ channel_fingerprint[-4:] }}</code>
                             </div>
                             {% endif %}
+                          </div>
+                        </div>
+                    </div>
 
-                        <!-- Custom key input -->
+                    <!-- Custom Channel Key Input (shown when Custom selected) -->
-                        <div class="mt-2 d-none" id="channelCustomInput">
+                    <div class="mb-4 d-none" id="channelCustomInput">
-                            <div class="input-group input-group-sm">
+                        <div class="security-box">
-                                <span class="input-group-text"><i class="bi bi-key"></i></span>
+                            <label class="form-label"><i class="bi bi-key me-1"></i> Custom Channel Key</label>
+                            <div class="input-group">
                                 <input type="text" name="channel_key_custom" class="form-control font-monospace"
                                        placeholder="XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX"
                                        pattern="[A-Za-z0-9]{4}(-[A-Za-z0-9]{4}){7}"
@@ -465,7 +450,6 @@
                             </div>
                         </div>
                     </div>
-                    </div>
                     
                     <!-- Advanced Options (DCT sub-options only) -->
                     <div class="mb-4 {% if not has_dct %}d-none{% endif %}" id="advancedOptionsContainer">

frontends/web/templates/index.html

@@ -25,10 +25,12 @@
     <div class="d-flex align-items-center justify-content-between">
         <div>
             <i class="bi bi-shield-lock me-2"></i>
-            <strong>Private Channel Active</strong>
+            <strong>Private Channel Mode</strong>
-            <span class="text-muted ms-2">Messages are isolated to this deployment</span>
+        </div>
+        <div class="key-capsule">
+            <span class="badge led-badge-yellow"><span class="led-indicator led-yellow me-1"></span>Key Loaded</span>
+            <code class="small ms-2">{{ channel_fingerprint }}</code>
         </div>
-        <code class="small">{{ channel_fingerprint }}</code>
     </div>
 </div>
 {% endif %}

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "stegasoo"
-version = "4.0.0"
+version = "4.0.1"
 description = "Secure steganography with hybrid photo + passphrase + PIN authentication"
 readme = "README.md"
 license = "MIT"

src/stegasoo/__init__.py

@@ -1,5 +1,5 @@
 """
-Stegasoo - Secure Steganography with Multi-Factor Authentication (v4.0.0)
+Stegasoo - Secure Steganography with Multi-Factor Authentication (v4.0.1)
 
 Changes in v4.0.0:
 - Added channel key support for deployment/group isolation
@@ -7,11 +7,11 @@ Changes in v4.0.0:
 - encode() and decode() now accept channel_key parameter
 """
 
-__version__ = "4.0.0"
+__version__ = "4.0.1"
 
 # Core functionality
 from .encode import encode
-from .decode import decode, decode_file
+from .decode import decode, decode_file, decode_text
 
 # Credential generation
 from .generate import (
@@ -158,6 +158,7 @@ __all__ = [
     "encode",
     "decode",
     "decode_file",
+    "decode_text",
     
     # Generation
     "generate_pin",

src/stegasoo/constants.py

@@ -1,5 +1,5 @@
 """
-Stegasoo Constants and Configuration (v4.0.0 - Channel Key Support)
+Stegasoo Constants and Configuration (v4.0.1 - Channel Key Support)
 
 Central location for all magic numbers, limits, and crypto parameters.
 All version numbers, limits, and configuration values should be defined here.
@@ -21,7 +21,7 @@ from pathlib import Path
 # VERSION
 # ============================================================================
 
-__version__ = "4.0.0"
+__version__ = "4.0.1"
 
 # ============================================================================
 # FILE FORMAT

src/stegasoo/crypto.py

@@ -624,12 +624,15 @@ def get_active_channel_key() -> Optional[str]:
     return get_channel_key()
 
 
-def get_channel_fingerprint() -> Optional[str]:
+def get_channel_fingerprint(key: Optional[str] = None) -> Optional[str]:
     """
-    Get a display-safe fingerprint of the configured channel key.
+    Get a display-safe fingerprint of a channel key.
+
+    Args:
+        key: Channel key (if None, uses configured key)
 
     Returns:
         Masked key like "ABCD-••••-••••-••••-••••-••••-••••-3456" or None
     """
     from .channel import get_channel_fingerprint as _get_fingerprint
-    return _get_fingerprint()
+    return _get_fingerprint(key)

src/stegasoo/steganography.py

@@ -56,23 +56,24 @@ EXT_TO_FORMAT = {
 }
 
 # =============================================================================
-# OVERHEAD CONSTANTS (v3.2.0 - Updated for date-independent format)
+# OVERHEAD CONSTANTS (v4.0.0 - Updated for channel key support)
 # =============================================================================
-# v3.2.0 Header format (no date field):
+# v4.0.0 Header format (with flags byte for channel key indicator):
 #   Magic:   4 bytes  (\x89ST3)
-#   Version: 1 byte   (4 for v3.2.0)
+#   Version: 1 byte   (5 for v4.0.0)
+#   Flags:   1 byte   (bit 0 = has channel key)
 #   Salt:    32 bytes
 #   IV:      12 bytes
 #   Tag:     16 bytes
 #   -----------------
-#   Total:   65 bytes
+#   Total:   66 bytes
 #
-# Previous v3.1.0 had date field (10 bytes + 1 byte length) = 76 bytes header
+# v3.2.0 had 65 bytes (no flags byte)
-# The old value of 104 was incorrect even for v3.1.0
+# v3.1.0 had date field (10 bytes + 1 byte length) = 76 bytes header
 
-HEADER_OVERHEAD = 65       # v3.2.0: Magic + version + salt + iv + tag
+HEADER_OVERHEAD = 66       # v4.0.0: Magic + version + flags + salt + iv + tag
 LENGTH_PREFIX = 4          # 4 bytes for payload length in LSB embedding
-ENCRYPTION_OVERHEAD = HEADER_OVERHEAD + LENGTH_PREFIX  # 69 bytes total
+ENCRYPTION_OVERHEAD = HEADER_OVERHEAD + LENGTH_PREFIX  # 70 bytes total
 
 # DCT output format options (v3.0.1)
 DCT_OUTPUT_PNG = 'png'

tests/test_stegasoo.py

@@ -1,11 +1,13 @@
 """
 Stegasoo Tests (v4.0.0)
 
-Tests for key generation, validation, encoding/decoding, and output formats.
+Tests for key generation, validation, encoding/decoding, output formats,
+and channel key functionality.
 
 Updated for v4.0.0:
 - Same API as v3.2.0 (passphrase, no date_str)
-- JPEG normalization for jpegio compatibility
+- Channel key support for deployment/group isolation
+- HEADER_OVERHEAD increased to 66 bytes (flags byte added)
 - Python 3.12 recommended (3.13 not supported)
 """
 
@@ -16,17 +18,20 @@ import io
 import stegasoo
 from stegasoo import (
     generate_pin,
-    generate_phrase,
+    generate_passphrase,
     generate_credentials,
     validate_pin,
     validate_message,
     validate_passphrase,
+    validate_channel_key,
     encode,
     decode,
     decode_text,
+    generate_channel_key,
+    get_channel_fingerprint,
     __version__,
 )
-from stegasoo.steganography import get_output_format, HEADER_OVERHEAD
+from stegasoo.steganography import get_output_format
 
 
 # =============================================================================
@@ -104,16 +109,16 @@ class TestKeygen:
             assert len(pin) == length
             assert pin.isdigit()
 
-    def test_generate_phrase_default(self):
+    def test_generate_passphrase_default(self):
-        """Default phrase should have 4 words (v3.2.0 change)."""
+        """Default passphrase should have 4 words (v3.2.0 change)."""
-        phrase = generate_phrase()
+        phrase = generate_passphrase()
         words = phrase.split()
         assert len(words) == 4  # Changed from 3 in v3.1.x
 
-    def test_generate_phrase_custom_length(self):
+    def test_generate_passphrase_custom_length(self):
-        """Phrase generation should work for custom lengths."""
+        """Passphrase generation should work for custom lengths."""
         for length in [3, 4, 5, 6, 8, 12]:
-            phrase = generate_phrase(length)
+            phrase = generate_passphrase(length)
             words = phrase.split()
             assert len(words) == length
 
@@ -287,19 +292,20 @@ class TestOutputFormat:
 
 
 # =============================================================================
-# Header Overhead Test (v3.2.0)
+# Header Overhead Test (v4.0.0)
 # =============================================================================
 
 class TestConstants:
     """Tests for constants and configuration."""
 
     def test_header_overhead_value(self):
-        """Header overhead should be 65 bytes (v3.2.0 fix)."""
+        """Header overhead should be 66 bytes (v4.0.0: added flags byte)."""
-        assert HEADER_OVERHEAD == 65
+        from stegasoo.steganography import HEADER_OVERHEAD
+        assert HEADER_OVERHEAD == 66
 
 
 # =============================================================================
-# Encode/Decode Tests (v3.2.0 Updated)
+# Encode/Decode Tests (v4.0.0 Updated)
 # =============================================================================
 
 class TestEncodeDecode:
@@ -474,8 +480,8 @@ class TestEncodeDecode:
 
         assert decoded.message == message
 
-    def test_filename_has_no_date(self, png_image):
+    def test_filename_format(self, png_image):
-        """v3.2.0: Output filename should not have date suffix."""
+        """Output filename should have random hex and date suffix."""
         result = encode(
             message="Test",
             reference_photo=png_image,
@@ -483,10 +489,10 @@ class TestEncodeDecode:
             passphrase="test phrase here now",
             pin="123456"
         )
-        # Filename should be like "a1b2c3d4.png", not "a1b2c3d4_20251227.png"
+        # Filename format: {random_hex}_{YYYYMMDD}.{ext}
-        # Check that there's no underscore followed by 8 digits
+        # e.g., "a1b2c3d4_20251227.png"
         import re
-        assert not re.search(r'_\d{8}\.', result.filename)
+        assert re.search(r'^[a-f0-9]{8}_\d{8}\.png$', result.filename)
 
 
 # =============================================================================
@@ -605,3 +611,155 @@ class TestBackwardCompatibility:
                 pin="123456",
                 date_str="2025-01-01"  # Removed parameter
             )
+
+
+# =============================================================================
+# Channel Key Tests (v4.0.0)
+# =============================================================================
+
+class TestChannelKey:
+    """Tests for channel key functionality (v4.0.0)."""
+
+    def test_generate_channel_key_format(self):
+        """Generated channel key should have correct format."""
+        key = generate_channel_key()
+        # Format: XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX (8 groups of 4)
+        assert len(key) == 39
+        parts = key.split('-')
+        assert len(parts) == 8
+        for part in parts:
+            assert len(part) == 4
+            assert part.isalnum()
+
+    def test_validate_channel_key_valid(self):
+        """Valid channel key should pass validation."""
+        key = generate_channel_key()
+        assert validate_channel_key(key)
+
+    def test_validate_channel_key_invalid(self):
+        """Invalid channel key should fail validation."""
+        assert not validate_channel_key("")
+        assert not validate_channel_key("invalid")
+        assert not validate_channel_key("ABCD-1234")  # Too short
+
+    def test_channel_fingerprint_format(self):
+        """Channel fingerprint should mask middle sections."""
+        key = "ABCD-1234-EFGH-5678-IJKL-9012-MNOP-3456"
+        fingerprint = get_channel_fingerprint(key)
+        assert fingerprint is not None
+        # First and last groups visible, middle masked
+        assert fingerprint.startswith("ABCD-")
+        assert fingerprint.endswith("-3456")
+        assert "••••" in fingerprint
+
+    def test_encode_decode_with_channel_key(self, png_image):
+        """Encode/decode should work with explicit channel key."""
+        message = "Secret with channel key!"
+        passphrase = "apple forest thunder mountain"
+        pin = "123456"
+        channel_key = generate_channel_key()
+
+        # Encode with channel key
+        result = encode(
+            message=message,
+            reference_photo=png_image,
+            carrier_image=png_image,
+            passphrase=passphrase,
+            pin=pin,
+            channel_key=channel_key
+        )
+
+        assert result.stego_image is not None
+
+        # Decode with same channel key
+        decoded = decode(
+            stego_image=result.stego_image,
+            reference_photo=png_image,
+            passphrase=passphrase,
+            pin=pin,
+            channel_key=channel_key
+        )
+
+        assert decoded.message == message
+
+    def test_decode_wrong_channel_key_fails(self, png_image):
+        """Decoding with wrong channel key should fail."""
+        message = "Secret message"
+        passphrase = "apple forest thunder mountain"
+        pin = "123456"
+        channel_key1 = generate_channel_key()
+        channel_key2 = generate_channel_key()
+
+        # Encode with one channel key
+        result = encode(
+            message=message,
+            reference_photo=png_image,
+            carrier_image=png_image,
+            passphrase=passphrase,
+            pin=pin,
+            channel_key=channel_key1
+        )
+
+        # Decode with different channel key should fail
+        with pytest.raises((stegasoo.DecryptionError, stegasoo.ExtractionError)):
+            decode(
+                stego_image=result.stego_image,
+                reference_photo=png_image,
+                passphrase=passphrase,
+                pin=pin,
+                channel_key=channel_key2
+            )
+
+    def test_encode_decode_public_mode(self, png_image):
+        """Encode/decode should work without channel key (public mode)."""
+        message = "Public message!"
+        passphrase = "apple forest thunder mountain"
+        pin = "123456"
+
+        # Encode without channel key (explicit public mode)
+        result = encode(
+            message=message,
+            reference_photo=png_image,
+            carrier_image=png_image,
+            passphrase=passphrase,
+            pin=pin,
+            channel_key=""  # Explicit public mode
+        )
+
+        # Decode without channel key
+        decoded = decode(
+            stego_image=result.stego_image,
+            reference_photo=png_image,
+            passphrase=passphrase,
+            pin=pin,
+            channel_key=""  # Explicit public mode
+        )
+
+        assert decoded.message == message
+
+    def test_channel_key_mismatch_public_vs_private(self, png_image):
+        """Decoding public message with channel key should fail."""
+        message = "Public message"
+        passphrase = "apple forest thunder mountain"
+        pin = "123456"
+
+        # Encode without channel key (public)
+        result = encode(
+            message=message,
+            reference_photo=png_image,
+            carrier_image=png_image,
+            passphrase=passphrase,
+            pin=pin,
+            channel_key=""  # Public mode
+        )
+
+        # Decode with channel key should fail
+        channel_key = generate_channel_key()
+        with pytest.raises((stegasoo.DecryptionError, stegasoo.ExtractionError)):
+            decode(
+                stego_image=result.stego_image,
+                reference_photo=png_image,
+                passphrase=passphrase,
+                pin=pin,
+                channel_key=channel_key
+            )