<?php

namespace SilverStripe\Forms;

use SilverStripe\Core\Convert;
use SilverStripe\ORM\FieldType\DBHTMLText;
use SilverStripe\View\Requirements;
use InvalidArgumentException;

/**
 * Defines a set of tabs in a form.
 * The tabs are build with our standard tabstrip javascript library.
 * By default, the HTML is generated using FieldHolder.
 *
 * <b>Usage</b>
 *
 * <code>
 * new TabSet(
 * 	$name = "TheTabSetName",
 * 	new Tab(
 * 		$title='Tab one',
 * 		new HeaderField("A header"),
 * 		new LiteralField("Lipsum","Lorem ipsum dolor sit amet enim.")
 * 	),
 * 	new Tab(
 * 		$title='Tab two',
 * 		new HeaderField("A second header"),
 * 		new LiteralField("Lipsum","Ipsum dolor sit amet enim.")
 * 	)
 * )
 * </code>
 */
class TabSet extends CompositeField {

	/**
	 * Use custom react component
	 *
	 * @var string
	 */
	protected $schemaComponent = 'Tabs';

	/**
	 * @var TabSet
	 */
	protected $tabSet;

	/**
	 * @var string
	 */
	protected $id;

	/**
	 * @param string $name Identifier
	 * @param string|Tab|TabSet $titleOrTab Natural language title of the tabset, or first tab.
	 * If its left out, the class uses {@link FormField::name_to_label()} to produce a title
	 * from the {@link $name} parameter.
	 * @param Tab|TabSet ...$tabs All further parameters are inserted as children into the TabSet
	 */
	public function __construct($name, $titleOrTab = null, $tabs = null) {
		if(!is_string($name)) {
			throw new InvalidArgumentException('Invalid string parameter for $name');
		}

		// Get following arguments
		$tabs = func_get_args();
		array_shift($tabs);

		// Detect title from second argument, if it is a string
		if($titleOrTab && is_string($titleOrTab)) {
			$title = $titleOrTab;
			array_shift($tabs);
		} else {
			$title = static::name_to_label($name);
		}

		// Normalise children list
		if(count($tabs) === 1 && (is_array($tabs[0]) || $tabs[0] instanceof FieldList)) {
			$tabs = $tabs[0];
		}

		// Ensure tabs are assigned to this tabset
		if($tabs) {
			foreach($tabs as $tab) {
				if ($tab instanceof Tab || $tab instanceof TabSet) {
					$tab->setTabSet($this);
				} else {
					throw new InvalidArgumentException("TabSet can only contain instances of other Tab or Tabsets");
				}
			}
		}

		parent::__construct($tabs);

		// Assign name and title (not assigned by parent constructor)
		$this->setName($name);
		$this->setTitle($title);
		$this->setID(Convert::raw2htmlid($name));
	}

	public function ID() {
		if($this->tabSet) {
			return $this->tabSet->ID() . '_' . $this->id . '_set';
		} else {
			return $this->id;
		}
	}

	/**
	 * Set custom HTML ID to use for this tabset
	 *
	 * @param string $id
	 * @return $this
	 */
	public function setID($id) {
		$this->id = $id;
		return $this;
	}

	/**
	 * Returns a tab-strip and the associated tabs.
	 * The HTML is a standardised format, containing a &lt;ul;
	 *
	 * @param array $properties
	 * @return DBHTMLText|string
	 */
	public function FieldHolder($properties = array()) {
		$obj = $properties ? $this->customise($properties) : $this;

		return $obj->renderWith($this->getTemplates());
	}

	/**
	 * Return a set of all this classes tabs
	 *
	 * @return FieldList
	 */
	public function Tabs() {
		return $this->children;
	}

	/**
	 * @param FieldList $children Assign list of tabs
	 */
	public function setTabs($children){
		$this->children = $children;
	}

	/**
	 * Assign to a TabSet instance
	 *
	 * @param TabSet $val
	 * @return $this
	 */
	public function setTabSet($val) {
		$this->tabSet = $val;
		return $this;
	}

	/**
	 * Get parent tabset
	 *
	 * @return TabSet
	 */
	public function getTabSet() {
		return $this->tabSet;
	}

	public function getAttributes() {
		return array_merge(
			$this->attributes,
			array(
				'id' => $this->ID(),
				'class' => $this->extraClass()
			)
		);
	}

	/**
	 * Add a new child field to the end of the set.
	 *
	 * @param FormField $field
	 */
	public function push(FormField $field) {
		if ($field instanceof Tab || $field instanceof TabSet) {
			$field->setTabSet($this);
		}
		parent::push($field);
	}

	/**
	 * Add a new child field to the beginning of the set.
	 *
	 * @param FormField $field
	 */
	public function unshift(FormField $field) {
		if ($field instanceof Tab || $field instanceof TabSet) {
			$field->setTabSet($this);
		}
		parent::unshift($field);
	}

	/**
	 * Inserts a field before a particular field in a FieldList.
	 *
	 * @param string $insertBefore Name of the field to insert before
	 * @param FormField $field The form field to insert
	 * @return FormField|null
	 */
	public function insertBefore($insertBefore, $field) {
		if ($field instanceof Tab || $field instanceof TabSet) {
			$field->setTabSet($this);
		}
		return parent::insertBefore($insertBefore, $field);
	}

	/**
	 * Inserts a field after a particular field in a FieldList.
	 *
	 * @param string $insertAfter Name of the field to insert after
	 * @param FormField $field The form field to insert
	 * @return FormField|null
	 */
	public function insertAfter($insertAfter, $field) {
		if ($field instanceof Tab || $field instanceof TabSet) {
			$field->setTabSet($this);
		}
		return parent::insertAfter($insertAfter, $field);
	}
}