` element in the template to display validation errors.
-
----
-
-### Pattern 2: Polling Image Display (`display.tpl` + `js/display.js`)
-
-Used by the `display` and `zap` modes to show collage progress. The server streams individual image responses, and the client alternates between two `
![]()
` tags to give the appearance of continuous updating.
-
-**Server side:**
-
-`ZAPDisplay` (in `lib/ZAPDisplay.class.php`) sets session variables from `$_POST` and renders `tpl/display.tpl`. The template declares `onload="go(this,['img1','img2'],5000);"` on the `` tag, which kicks off the polling loop.
-
-`ZAPZap` (in `lib/ZAPZap.class.php`) handles each individual poll request. On each invocation it either:
-- Downloads the next source image (if `$_SESSION['words']` is not empty) and streams it via `ImgIOTools::onScreen()`.
-- Starts the next collage (if `$_SESSION['words']` is empty but `$_SESSION['collages'] > 0`).
-- Adds the next source image to the current collage via `ImgProcess::addToCanvas()`.
-- Signals completion by destroying the session and returning an error string (which triggers the `onerror` handler in JavaScript).
-
-**Client side (`js/display.js`):**
-
-```javascript
-var go = function(b, img_id, interval) {
- var i = 0;
- var img0 = document.getElementById(img_id[0]);
- var img1 = document.getElementById(img_id[1]);
- var img = [img0, img1];
- var activeImage = 1; // index of visible image
- var url = 'index.php?mode=zap';
-
- if (isNaN(interval)) {
- interval = 5000;
- }
-
- // Trigger the next image fetch after the current one has loaded.
- img[0].onload = img[1].onload = function() {
- var inactiveImage = activeImage === 0 ? 1 : 0;
- img[activeImage].style.display = 'none';
- img[inactiveImage].style.display = '';
- activeImage = inactiveImage;
-
- setTimeout(function() {
- img[inactiveImage].src = url + '&i=' + (i++);
- }, interval);
- };
-
- // When the backend signals completion it returns a small HTML page.
- // Show the ready link and stop fetching new images.
- img[0].onerror = img[1].onerror = function() {
- document.getElementById('ready').innerHTML = '
Ready';
- };
-
- // Kick off the first request.
- img[activeImage].src = url + '&i=' + (i++);
-};
-```
-
-**How the polling cadence works:**
-
-1. `body onload="go(this,['img1','img2'],5000)"` starts the loop with a 5 s interval between successive fetches.
-2. Two `
![]()
` tags (`#img1` and `#img2`) are used — one is visible, the other hidden.
-3. When the visible image finishes loading (`img.onload`), the pair swaps: the loaded image is hidden, and the previously hidden one is shown. After a 5 s delay (`setTimeout`), the newly hidden image's `src` is set to `index.php?mode=zap&i={counter}`.
-4. Each request to `mode=zap` returns raw image data (a `Content-Type: image/jpeg` response). The browser renders it into the `
![]()
` tag, triggering `onload` again and continuing the cycle.
-5. When `ZAPZap` finishes all collages, it destroys the session and returns an HTML error string instead of image data. The `
![]()
` tag fails to load an image, triggering `onerror`, which replaces the image area with a "Ready" link.
-
-**To reproduce this pattern in a new handler:**
-
-1. Create a template with two `
![]()
` elements and ``.
-2. Include `js/display.js` (or copy the pattern into your own JS file).
-3. Create a `ZAP{Mode}` handler that returns raw image data (set `Content-Type` headers and use `echo` with `readfile()` or Imagick's `getImageBlob()`).
-4. Signal completion by returning a non-image response that will trigger `onerror` on the `
![]()
` tag.
-
----
-
-## Summary: Creating a New Feature End-to-End
-
-To add a completely new feature to ZapMachine, follow these steps:
-
-1. **Add configuration** in `conf/conf.php` (constants, engine names) if needed.
-2. **Create the handler** `lib/ZAP{Mode}.class.php` with `getContent()` returning a string.
-3. **Create the template** `tpl/{mode}.tpl` using the `ob_start`/`include`/`extract`/`ob_get_clean` pattern.
-4. **Choose an interactive pattern:**
- - For form input with validation: add a form in the template, write a JS validation function, and include the script.
- - For polling/image updates: use the two-`
![]()
` swap with `onload`/`onerror`.
-5. **Create a JS file** in `www/js/` and reference it from the template's ``.
-6. **Test the route** at `index.php?mode={ModeName}`.
-7. **Test from CLI** using the bootstrap pattern in `cli_scripts/test.php` (remember `chdir(__DIR__)` + manual `Session::start()` if needed).
+# yet to come
+- Logfile also generated in imgProcess Class (0.9.2)
+- Number and camera filename (virgin images) input (0.9.3)
+- Proper stop meganism (0.9.1)
+- better error handling: dead links give dynamicly generated image thats allso used in collage (0.9.3)
+- visualisation of logfile, so viewers can see what is happening (0.9.1)
+- replacing all 'random' image processing parameters (0.7)
diff --git a/docs/framework_guide.md b/docs/framework_guide.md
new file mode 100644
index 0000000..4bff8d8
--- /dev/null
+++ b/docs/framework_guide.md
@@ -0,0 +1,479 @@
+# ZAP Framework Guide
+
+This document explains the internal architecture of ZapMachine and provides step‑by‑step instructions for extending it with new handlers, templates, and interactive elements.
+
+## Architecture Overview
+
+### Front-Controller Routing (`?mode=X` → `ZAPController` → `ZAP{Mode}`)
+
+All HTTP requests enter through `www/index.php`. The front controller reads the `mode` query parameter and dispatches to a class whose name is formed as `ZAP` + the ucfirst'd mode value.
+
+```php
+// www/index.php (simplified)
+$mode = isset($_GET['mode']) ? $_GET['mode'] : 'home';
+require_once '..' . DIRECTORY_SEPARATOR . 'conf' . DIRECTORY_SEPARATOR . 'init.php';
+$config = Config::getInstance();
+$config->register('engines', $search_engines);
+$frontcontroller = new ZAPController($mode);
+$output = $frontcontroller->fetch();
+print($output);
+```
+
+`ZAPController` (in `lib/ZAPController.class.php`) constructs the class name from a prefix (`ZAP`) and the mode, verifies it exists via the autoloader, instantiates it, and calls `getContent()`:
+
+```php
+class ZAPController {
+ private $prefix = 'ZAP';
+
+ public function __construct($mode = 'home') {
+ $mode = trim(strip_tags($mode));
+ $this->mode = ucfirst($mode);
+ $clazz = $this->prefix . $this->mode;
+ if (!class_exists($clazz)) {
+ die('Wrong parameter');
+ }
+ $this->action = new $clazz();
+ }
+
+ public function fetch() {
+ return $this->action->getContent();
+ }
+}
+```
+
+**Registered modes and their handlers:**
+
+| `?mode=` | Class | Template | Purpose |
+|----------|-------|----------|---------|
+| `home` (default) | `ZAPHome` | `tpl/index.tpl` | Word-input form |
+| `display` | `ZAPDisplay` | `tpl/display.tpl` | Collage-generation progress screen |
+| `zap` | `ZAPZap` | *(raw image output)* | Downloads images & processes collages, returns image blobs |
+
+---
+
+### Autoloader
+
+`conf/init.php` registers an `spl_autoload_register` callback that searches every directory on the include path for both `{ClassName}.class.php` and `{ClassName}.interface.php`:
+
+```php
+spl_autoload_register(function ($class_name) {
+ $include_path_tokens = explode(PATH_SEPARATOR, get_include_path());
+ foreach ($include_path_tokens as $prefix) {
+ $path[0] = $prefix . DIRECTORY_SEPARATOR . $class_name . '.interface.php';
+ $path[1] = $prefix . DIRECTORY_SEPARATOR . $class_name . '.class.php';
+ foreach ($path as $thisPath) {
+ if (file_exists($thisPath)) {
+ require_once $thisPath;
+ return;
+ }
+ }
+ }
+});
+```
+
+The include path is built from these directories (relative to the project root):
+
+| Constant | Directory |
+|----------|-----------|
+| `ZAP_RESOURCE_DIR` | `resource/` — search-engine implementations |
+| `ZAP_UTILS_DIR` | `utils/` — utility classes (Session, ZAPCurl, Log) |
+| `ZAP_SESSIONS_DIR` | `sessions/` |
+| `ZAP_LIB_DIR` | `lib/` — core handlers and image processing |
+| `ZAP_TPL_DIR` | `tpl/` — templates |
+| `ZAP_CONF_DIR` | `conf/` — configuration |
+
+This means any `.class.php` or `.interface.php` file placed in one of those directories is automatically found — no manual `require_once` calls needed for library classes.
+
+---
+
+### Config Singleton
+
+Configuration values that must be accessible from any class are managed through `Config` (`conf/Config.class.php`), a classic singleton:
+
+```php
+$config = Config::getInstance();
+$config->register('engines', $search_engines); // store
+$engines = $config->retrieve('engines'); // retrieve — returns false if not found
+```
+
+The singleton is wired in `www/index.php` immediately after `init.php` is loaded.
+
+---
+
+### Session Management
+
+The `Session` class (`utils/Session.class.php`) wraps PHP's native sessions:
+
+```php
+Session::start('ZAP'); // Begin session (sessions named 'ZAP')
+Session::reset(); // Clear $_SESSION array
+Session::deleteCookie(); // Remove client-side session cookie
+Session::destroy(); // Reset + delete cookie + session_destroy()
+```
+
+Session data is stored verbatim in `$_SESSION` and uses these keys:
+
+| Key | Type | Set by | Purpose |
+|-----|------|--------|---------|
+| `words` | `string[]` | `ZAPDisplay` | Keyword list for image search |
+| `folder` | `string` | `ZAPDisplay` | Absolute path to session folder |
+| `collages` | `int` | `ZAPDisplay` | Number of collages to generate |
+| `width` | `int` | `ZAPDisplay` | Collage width in pixels |
+| `height` | `int` | `ZAPDisplay` | Collage height in pixels |
+| `images` | `string[]` | `ZAPZap` | Queue of source image paths for current collage |
+| `imgOriginal` | `string[]` | `ZAPZap` | Immutable copy of the original image list |
+| `collageNr` | `int` | `ZAPZap` | Current collage sequence number |
+
+**CLI note:** Session is only started automatically in web mode. See [CLI Bootstrap](#cli-bootstrap) below.
+
+---
+
+### Plugin-Based Search Engines
+
+Search engines implement the `Search` interface (`resource/Search.interface.php`):
+
+```php
+interface Search {
+ public function setQuery($word);
+ public function setParam($key, $value);
+ public function getData();
+}
+```
+
+Each engine class lives in `resource/` and returns data in a universal array format:
+
+```php
+$data['result'] = true; // Boolean: success / failure
+$data['engine'] = __CLASS__; // Engine name, e.g. 'Brave'
+$data['results'][0]['clickurl'] = '...'; // Image URL to download
+$data['results'][0]['referer'] = '...'; // Source page URL
+$data['results'][0]['thumb'] = '...'; // Thumbnail URL
+```
+
+Available engines are registered as an array of names in `conf/conf.php` and wired through the Config singleton at runtime. `ImgSearch` randomly selects an engine from the registered list each time it runs:
+
+```php
+$config = Config::getInstance();
+$engines = $config->retrieve('engines');
+$this->engine = $engines[array_rand($engines)];
+```
+
+**Current engine:** `Brave` (`resource/Brave.class.php`) — uses the Brave Search API.
+
+To add a new engine:
+1. Create `resource/YourEngine.class.php` implementing `Search`.
+2. Add `'yourengine'` to the `$search_engines` array in `conf/conf.php`.
+
+---
+
+### Image Processing Pipeline
+
+The image pipeline runs entirely server-side through three classes in `lib/`:
+
+1. **`ImgSearch`** (`lib/ImgSearch.class.php`) — searches for an image URL via a registered engine, downloads the file, validates its MIME type (`image/jpeg`, `image/gif`, `image/png`), and saves it to the session folder.
+
+2. **`ImgProcess`** (`lib/ImgProcess.class.php`) — constructs collages using ImageMagick. Each collage starts with `createBasicCanvas()` (zoom-crops the first source image) then layers additional images via `addToCanvas()` (random transparency + composite).
+
+3. **`ImgIOTools`** (`lib/ImgIOTools.class.php`) — handles output: `onScreen()` streams an Imagick object as an HTTP image response; `urlOnScreen()` loads a file path first; `saveImg()` writes to disk.
+
+4. **`ImgTools`** (`lib/ImgTools.class.php`) — utility functions: `zoomCrop()`, `transparantRandom()`, `randomRotate()`, `resize()`, `recolor()`, `convertGifsToPng()`.
+
+---
+
+### CLI Bootstrap
+
+CLI scripts (in `cli_scripts/`) bootstrap the application differently from web requests. Because `init.php` skips `Session::start()` when `php_sapi_name() === 'cli'`, CLI scripts must handle sessions manually if needed.
+
+**Example — `cli_scripts/test.php`:**
+
+```php
+#!/usr/bin/env php
+register('engines', $search_engines);
+```
+
+Key differences from the web entry point:
+- `chdir(__DIR__)` is **required** before `require_once 'init.php'` because `init.php` uses `realpath('.')` to define `ZAP_APP_BASE_DIR`.
+- `Session::start()` is **not called** — the `init.php` condition `php_sapi_name() !== 'cli'` guards against it.
+- You must explicitly register engines with `Config::getInstance()->register('engines', …)` because `www/index.php` normally does this.
+
+---
+
+### Logging
+
+The `Log` class (`utils/Log.class.php`) writes timestamped messages to a session folder. It is used by `ImgSearch` (controlled by the `ZAP_LOG` constant in `conf/conf.php`). Each log call appends to both `log.txt` (plain text) and `log.xml` (XML-friendly) in the session's output directory.
+
+```php
+if (ZAP_LOG == true) {
+ $log = new Log($this->folder);
+ $log->addToLog('ok', 'Search: ', "downloaded to $imageName");
+ $log->addToLog('error', 'Search: ', 'bad search data received');
+}
+```
+
+---
+
+## Template Rendering Pipeline
+
+The template system is a minimal PHP-native pattern built around `ob_start()` / `include` / `extract()` / `ob_get_clean()`. There is no template engine — templates are plain PHP files that receive variables via the symbol table.
+
+### How Templates Work
+
+Every `ZAP{Mode}` handler follows the same rendering pattern:
+
+```php
+class ZAPHome {
+ private $template = 'index'; // corresponds to tpl/index.tpl
+ private $tpl = '';
+
+ public function __construct() {
+ $this->ver = ZAP_VERSION;
+ extract(get_object_vars($this)); // ← makes all private properties available as $variables
+
+ ob_start(); // ← start output buffer
+ include getZAPTemplate($this->template); // ← include the .tpl file
+ $this->tpl .= ob_get_clean(); // ← capture buffer content, clean buffer
+ }
+
+ public function getContent() {
+ return $this->tpl;
+ }
+}
+```
+
+**Step by step:**
+
+1. Properties are set in the constructor (often from `$_POST`, `$_SESSION`, or constants like `ZAP_VERSION`).
+2. `extract(get_object_vars($this))` promotes every private property to a local variable in the current symbol table. A property `$this->template = 'index'` becomes `$template = 'index'`.
+3. `ob_start()` begins capturing all output.
+4. `include getZAPTemplate($this->template)` includes the file `tpl/{name}.tpl`. The included file inherits the current symbol table, so it can use `$ver`, `$folder`, `$words`, etc. directly.
+5. `ob_get_clean()` retrieves the captured HTML and closes the buffer.
+6. `getContent()` returns the accumulated output string, which `ZAPController::fetch()` returns to `index.php` for `print()`.
+
+### The `getZAPTemplate()` Helper
+
+```php
+function getZAPTemplate($tplname) {
+ $tplfile = $tplname . '.tpl';
+ $tplfilepath = ZAP_APP_BASE_DIR . DIRECTORY_SEPARATOR
+ . ZAP_TPL_DIR . DIRECTORY_SEPARATOR . $tplfile;
+ if (file_exists($tplfilepath)) {
+ return $tplfilepath;
+ } else {
+ return ERROR_PREFIX . 'No template';
+ }
+}
+```
+
+All templates live in the `tpl/` directory and have the `.tpl` extension. The helper resolves the absolute path so the `include` call works from any working directory.
+
+### Adding a New Template
+
+To add a new page/view:
+
+1. **Create the `ZAP{Mode}` handler** in `lib/`. The class must be named `ZAP{Mode}` (case-sensitive, PascalCase after the prefix) and must implement a `getContent()` method that returns a string:
+
+ ```php
+ pageTitle = 'My Example Page';
+ extract(get_object_vars($this));
+
+ ob_start();
+ include getZAPTemplate($this->template);
+ $this->tpl .= ob_get_clean();
+ }
+
+ public function getContent() {
+ return $this->tpl;
+ }
+ }
+ ```
+
+2. **Create the template** at `tpl/example.tpl`:
+
+ ```php
+
+
+
Example — <?php echo $pageTitle; ?>
+
+
+
ZAP version
+
+
+ ```
+
+3. **Use the route:** Navigate to `index.php?mode=example`. The autoloader finds `ZAPExample` in `lib/`, the front controller instantiates it, and `getZAPTemplate()` loads `tpl/example.tpl`.
+
+No registration step is required — the front controller's naming convention (`ZAP` + ucfirst(mode)) and the autoloader handle discovery automatically.
+
+---
+
+## Adding Interactive Elements
+
+This section documents the two interactive-element patterns used in the application. Each pattern pairs a server-side template with a client-side JavaScript file.
+
+### Pattern 1: Form with Client-Side Validation (`index.tpl` + `js/main.js`)
+
+Used by `ZAPHome` to collect word inputs, validate them in the browser, and POST to the `display` mode.
+
+**Server side (`ZAPHome` in `lib/ZAPHome.class.php`):**
+
+The handler passes two template variables into `tpl/index.tpl`:
+- `$ver` — the ZAP version string.
+- `$status` — an optional status message from the query string (`?stat=...`).
+
+The template renders a `