<?php

/** @see FLY_TagBuilder_RenderMode */
require_once 'FLY/TagBuilder/RenderMode.php';


/**
 * This class can be used to generate HTML tags programmatically.
 *
 * It can compose the definition of an HTML tag, its attributes, CSS styles and tag content.<br>
 * Once defined, the class can return the HTML for the specified tag.<br>
 *
 * @package FLY
 * @author Yves Feupi Lepatio
 */
class FLY_TagBuilder
{
    /**
     * Name of the HTML tag.
     * @var string
     */
    protected $_tagName = '';

    /**
     * Inner content of the tag.
     * @var string
     */
    protected $_innerHtml = '';

    /**
     * Tag's attributes.
     * @var array
     */
    protected $_attributes = array();

    /**
     * Standard inline tags.
     * @var array
     */
    protected $_inlineTags = array (
        'meta', 'link', 'img', 'br', 'input', 'hr'
    );

    /**
     * Gets the tag name.
     *
     * @return string
     */
    public function getTagName()
    {
        return $this->_tagName;
    }

    /**
     * Gets all tag's attributes.
     *
     * The returned array can be structured like this:
     * array('attr_1', 'attr_2', ...)
     *
     * @return array Returns the array of the attributes; an empty array otherwise.
     */
    public function getAttributes()
    {
        return $this->_attributes;
    }

    /**
     * Sets the inner content of the tag.
     *
     * @param string $html
     * @return FLY_TagBuilder
     */
    public function setInnerHtml($html)
    {
        $this->_innerHtml = (string) $html;

        return $this;
    }

    /**
     * Creates a new tag.
     *
     * @param string $tagName The name of the tag.
     * @throws InvalidArgumentException if the tag name is malformed
     * @return void
     */
    public function __construct($tagName)
    {
        if ( ! preg_match('/^[a-z][a-z0-9]*$/i', $tagName))
        {
            throw new InvalidArgumentException('`' . $tagName . '` is not a valid tag name');
        }

        $this->_tagName = strtolower($tagName);
    }

    /**
     * Static method for initialization.
     *
     * @param string $tagName The name of the tag.
     * @return FLY_TagBuilder
     */
    public static function CreateTagBuilder($tagName)
    {
        return new self($tagName);
    }

    /**
     * toString()
     *
     * @param int $renderMode The int must be a const of {@link FLY_TagBuilder_RenderMode}.
     *        Note: The default value is <code>FLY_TagBuilder_RenderMode::NORMAL</code>.
     * @return string
     */
    public function toString($renderMode = FLY_TagBuilder_RenderMode::NORMAL)
    {
        $result = '<' . $this->_tagName . $this->_buildAttributes();

        switch ($renderMode)
        {
            case FLY_TagBuilder_RenderMode::END_TAG:
                $result = '</' . $this->_tagName . '>';
                break;

            case FLY_TagBuilder_RenderMode::SELF_CLOSING:
                $result .= ' />';
                break;

            case FLY_TagBuilder_RenderMode::START_TAG:
                $result .= '>';
                break;

            case FLY_TagBuilder_RenderMode::NORMAL:
            default:
                $result .= $this->_isInlineTag($this->_tagName)
                           ? ' />'
                           : sprintf('>%s</%s>', $this->_innerHtml, $this->_tagName);
                break;
        }

        return $result;
    }

    /**
     * _isInlineTag()
     *
     * @param string $tagName
     * @return bool
     */
    protected function _isInlineTag($tagName)
    {
        return in_array($tagName, $this->_inlineTags);
    }

    /**
     * Returns the attributes formatted like they are in a tag. e.g: class="bg title" src=""
     *
     * @return string
     */
    protected function _buildAttributes()
    {
        if (0 == count($this->_attributes))
        {
            return '';
        }

        $result = '';

        if ($this->hasAttribute('id'))
        {
            $result .= sprintf(' id="%s"', $this->_attributes['id']);
        }
        if ($this->hasAttribute('class'))
        {
            $result .= sprintf(' class="%s"', $this->_attributes['class']);
        }

        $this->removeAttributes(array('id', 'class'));

        foreach ($this->_attributes as $name => $value)
        {
            $result .= sprintf(' %s="%s"', $name, $value);
        }

        return $result;
    }

    /**
     * removeAttributes()
     *
     * @return FLY_TagBuilder
     */
    public function removeAttributes(array $names)
    {
        foreach ($names as $name)
        {
            $this->removeAttribute($name);
        }

        return $this;
    }

    /**
     * removeAttribute()
     *
     * @name string $name
     * @return FLY_TagBuilder
     */
    public function removeAttribute($name)
    {
        if ($this->hasAttribute($name))
        {
            unset($this->_attributes[$name]);
        }

        return $this;
    }

    /**
     * hasAttribute()
     *
     * @return bool
     */
    public function hasAttribute($name)
    {
        $bool = array_key_exists($name, $this->_attributes);

        return $bool;
    }

    /**
     * Merges the attributes.
     *
     * @param array $attributes      A collection of pairs ("attributeName" => "value")
     * @param bool  $replaceExisting Replace existing attribute or not
     * @return FLY_TagBuilder
     * @throws InvalidArgumentException if the attribute name is malformed
     */
    public function mergeAttributes(array $attributes, $replaceExisting = true)
    {
        foreach ($attributes as $name => $value)
        {
            $this->mergeAttribute($name, $value, $replaceExisting);
        }

        return $this;
    }

    /**
     * Merges the attribute.
     *
     * @param string $name            The attribute name
     * @param string $value           The attribute value
     * @param bool   $replaceExisting Replace existing attribute or not
     * @return FLY_TagBuilder
     * @throws InvalidArgumentException if the attribute name is malformed
     */
    public function mergeAttribute($name, $value, $replaceExisting = true)
    {
        if ( ! preg_match('/^[a-z][a-z0-9]+$/i', $name))
        {
            throw new InvalidArgumentException('The attribute name `' . $name . '` is not well-named');
        }

        $name  = strtolower($name);
        $value = trim($value);

        if (($name == 'class') && ! $replaceExisting)
        {
            $this->addCssClass($value);
        }

        if ($replaceExisting || ! $this->hasAttribute($name))
        {
            $this->_attributes[$name] = $value;
        }

        return $this;
    }

    /**
     * Adds CSS value.
     *
     * @param string $value
     * @return FLY_TagBuilder
     */
    public function addCssClass($value)
    {
        $value = str_replace('\s+', ' ', trim($value));

        if ($this->hasAttribute('class') && ($value != ''))
        {
            $cssValues = preg_split('/ /', $value);

            foreach ($cssValues as $cssValue)
            {
                if (false === strpos($this->_attributes['class'], $cssValue))
                {
                    $this->_attributes['class'] .= ' ' . $cssValue;
                }
            }
        }
        else
        {
            $this->_attributes['class'] = $value;
        }

        return $this;
    }

    /**
     * Removes CSS class.
     *
     * @param string $value
     * @return FLY_TagBuilder
     */
    public function removeCssClass($value)
    {
        $value = str_replace('\s+', ' ', trim($value));

        if ($this->hasAttribute('class') && ($value != ''))
        {
            $cssValues = preg_split('/ /', $value);

            foreach ($cssValues as $cssValue)
            {
                if (false !== strpos($this->_attributes['class'], $cssValue))
                {
                    $this->_attributes['class'] = preg_replace(
                        "/^(?:{$cssValue}\s)?(.*?)(?:\s{$cssValue})?(.*?)(?:\s{$cssValue})?$/",
                        '$1$2',
                        $this->_attributes['class']
                    );
                }
            }
        }

        return $this;
    }
}