<?php

use Qs\Html;

class Qs_View_Helper_TreeView extends Zend_View_Helper_Abstract
{
    public function treeView($tree, $selectedId = null, $attribs = [])
    {
        $parent = null;
        $this->prepareTree($tree, $parent, $selectedId);
        return $this->renderItems($tree, $attribs);
    }

    protected function prepareTree(&$tree, &$parent, $selectedId)
    {
        if ($parent) {
            $parent['opened'] = false;
        }
        foreach ($tree as &$item) {
            $item['selected'] = $item['id'] == $selectedId;
            if (!empty($item['sub'])) {
                $this->prepareTree($item['sub'], $item, $selectedId);
            }
            if (($item['id'] == $selectedId || Qs_Array::get($item, 'opened'))) {
                if ($parent) {
                    $parent['opened'] = true;
                }
                $item['opened'] = true;
            }
        }
        return $this;
    }

    protected function renderItems($tree, $attribs, $level = 1)
    {
        $xhtml = '';
        $index = 0;
        $count = count($tree);
        foreach ($tree as $item) {
            $xhtml .= $this->renderItem($item, $level, ++$index == $count);
        }
        return Html::renderContainer('ul', $xhtml, $attribs);
    }

    protected function renderItem($item, $level, $last)
    {
        $attribs = [
            'class' => [],
        ];
        if (($isTop = (1 == $level))) {
            $attribs['class'][] = 'top-level';
        }
        $xhtml = '';
        $opened = Qs_Array::get($item, 'opened');
        if (!empty($item['sub'])) {
            $branchClass = $opened ? 'collapsable' : 'expandable';
            $attribs['class'][] = $branchClass;
            if ($last) {
                $attribs['class'][] = 'last' . ucfirst($branchClass);
            }
            $xhtml .= $this->renderHitarea($isTop, $opened, $last);
        }
        $xhtml .= $this->renderLink($item, $isTop);
        if (!empty($item['sub'])) {
            $ulAttribs = [];
            if (!$opened) {
                $ulAttribs['style'] = 'display:none';
            }
            $xhtml .= $this->renderItems($item['sub'], $ulAttribs, $level + 1);
        } elseif ($last) {
            $attribs['class'][] = 'last';
        }
        $attribs['class'] = implode(' ', $attribs['class']);
        return Html::renderContainer('li', $xhtml, $attribs);
    }

    protected function renderLink($item, $isTop)
    {
        $attribs = ['href' => $item['url'], 'class' => []];
        if ($isTop) {
            $attribs['class'][] = 'top-level';
        }
        if ($item['selected']) {
            $attribs['class'][] = 'selected';
        }
        if (!empty($attribs['class'])) {
            $attribs['class'] = implode(' ', $attribs['class']);
        } else {
            unset($attribs['class']);
        }
        return Html::renderContainer('a', $item['title'], $attribs);
    }

    protected function renderHitarea($isTop, $opened, $last)
    {
        $class = ['hitarea'];
        if ($isTop) {
            $class[] = 'top-level-hitarea';
        }
        $class[] = ($stateClass = ($opened ? 'collapsable' : 'expandable') . '-hitarea');
        if ($last) {
            $class[] = 'last' . ucfirst($stateClass);
        }
        return Html::renderContainer('div', '', ['class' => implode(' ', $class)]);
    }
}