Plugin Hooks
============

Application Hooks
-----------------

Hooks can extend, replace, filter data or change the default behavior. Each hook is identified with a unique name, example: `controller:calendar:user:events`

### Listen on hook events

In your `initialize()` method you need to call the method `on()` of the class `Kanboard\Core\Plugin\Hook`:

```php
$this->hook->on('hook_name', $callable);
```

The first argument is the name of the hook and the second is a PHP callable.

### Hooks executed only once

Some hooks can have only one listener:

#### model:subtask-time-tracking:calculate:time-spent

- Override time spent calculation when sub-task timer is stopped
- Arguments:
    - `$user_id` (integer)
    - `$start` (DateTime)
    - `$end` (DateTime)

#### model:subtask-time-tracking:calendar:events

- Override subtask time tracking events to display the calendar
- Arguments:
    - `$user_id` (integer)
    - `$events` (array)
    - `$start` (string, ISO-8601 format)
    - `$end` (string, ISO-8601 format)

### Merge hooks

"Merge hooks" act in the same way as the function `array_merge`. The hook callback must return an array. This array will be merged with the default one.

Example to add events in the user calendar:

```php
class Plugin extends Base
{
    public function initialize()
    {
        $container = $this->container;

        $this->hook->on('controller:calendar:user:events', function($user_id, $start, $end) use ($container) {
            $model = new SubtaskForecast($container);
            return $model->getCalendarEvents($user_id, $end); // Return new events
        });
    }
}
```

List of merging hooks:

#### controller:calendar:project:events

- Add more events to the project calendar
- Arguments:
    - `$project_id` (integer)
    - `$start` Calendar start date (string, ISO-8601 format)
    - `$end` Calendar` end date (string, ISO-8601 format)

#### controller:calendar:user:events

- Add more events to the user calendar
- Arguments:
    - `$user_id` (integer)
    - `$start` Calendar start date (string, ISO-8601 format)
    - `$end` Calendar end date (string, ISO-8601 format)

Asset Hooks
-----------

Asset hooks can be used to add a new stylesheet easily or a new JavaScript file in the layout. You can use this feature to create a theme and override all Kanboard default styles.

Example to add a new stylesheet:

```php
<?php

namespace Kanboard\Plugin\Css;

use Kanboard\Core\Plugin\Base;

class Plugin extends Base
{
    public function initialize()
    {
        $this->hook->on('template:layout:css', 'plugins/Css/skin.css');
    }
}
```

List of asset Hooks:

- `template:layout:css`
- `template:layout:js`

Template Hooks
--------------

Template hooks allow to add new content in existing templates.

Example to add new content in the dashboard sidebar:

```php
$this->template->hook->attach('template:dashboard:sidebar', 'myplugin:dashboard/sidebar');
```

This call is usually defined in the `initialize()` method.
The first argument is name of the hook and the second argument is the template name.

Template names prefixed with the plugin name and colon indicate the location of the template.

Example with `myplugin:dashboard/sidebar`:

- `myplugin` is the name of your plugin (lowercase)
- `dashboard/sidebar` is the template name
- On the filesystem, the plugin will be located here: `plugins\Myplugin\Template\dashboard\sidebar.php`
- Templates are written in pure PHP (don't forget to escape data)

Template names without prefix are core templates.

List of template hooks:

- `template:auth:login-form:before`
- `template:auth:login-form:after`
- `template:dashboard:sidebar`
- `template:config:sidebar`
- `template:config:integrations`
- `template:project:integrations`
- `template:user:integrations`
- `template:export:sidebar`
- `template:layout:head`
- `template:layout:top`
- `template:layout:bottom`
- `template:project:dropdown`: "Actions" menu on left in different project views
- `template:project:header:before`
- `template:project:header:after`
- `template:project-user:sidebar`
- `template:task:sidebar:information`
- `template:task:sidebar:actions`
- `template:user:sidebar:information`
- `template:user:sidebar:actions`
- `template:app:filters-helper:before`
- `template:app:filters-helper:after`

Another template hooks can be added if necessary, just ask on the issue tracker.