<?php

// Data-aware form generator

class scbForms {

	const token = '%input%';

	protected static $cur_name;

	static function input( $args, $formdata = false ) {
		// setle on singular keys
		foreach ( array( 'name', 'value' ) as $key ) {
			$old = $key . 's';

			if ( isset( $args[$old] ) ) {
				$args[$key] = $args[$old];
				unset( $args[$old] );
			}
		}

		if ( !empty( $formdata ) ) {
			$form = new scbForm( $formdata );
			return $form->input( $args );
		}

		if ( empty( $args['name'] ) )
			return trigger_error( 'Empty name', E_USER_WARNING );

		$args = wp_parse_args( $args, array(
			'desc' => '',
			'desc_pos' => '',
		) );

		$val_is_array = isset( $args['value'] ) && is_array( $args['value'] );

		if ( isset( $args['extra'] ) && !is_array( $args['extra'] ) )
			$args['extra'] = shortcode_parse_atts( $args['extra'] );

		self::$cur_name = self::get_name( $args['name'] );

		switch ( $args['type'] ) {
			case 'select':
			case 'radio':
				if ( ! $val_is_array )
					return trigger_error( "'value' argument is expected to be an array", E_USER_WARNING );

				return self::_single_choice( $args );
				break;
			case 'checkbox':
				if ( $val_is_array )
					return self::_multiple_choice( $args );
				else
					return self::_checkbox( $args );
				break;
			default:
				return self::_input( $args );
		}
	}


// ____________UTILITIES____________


	// Generates a table wrapped in a form
	static function form_table( $rows, $formdata = NULL ) {
		$output = '';
		foreach ( $rows as $row )
			$output .= self::table_row( $row, $formdata );

		$output = self::form_table_wrap( $output );

		return $output;
	}

	// Generates a form
	static function form( $inputs, $formdata = NULL, $nonce ) {
		$output = '';
		foreach ( $inputs as $input )
			$output .= self::input( $input, $formdata );

		$output = self::form_wrap( $output, $nonce );

		return $output;
	}

	// Generates a table
	static function table( $rows, $formdata = NULL ) {
		$output = '';
		foreach ( $rows as $row )
			$output .= self::table_row( $row, $formdata );

		$output = self::table_wrap( $output );

		return $output;
	}

	// Generates a table row
	static function table_row( $args, $formdata = NULL ) {
		return self::row_wrap( $args['title'], self::input( $args, $formdata ) );
	}


// ____________WRAPPERS____________


	// Wraps the given content in a <form><table>
	static function form_table_wrap( $content, $nonce = 'update_options' ) {
		$output = self::table_wrap( $content );
		$output = self::form_wrap( $output, $nonce );

		return $output;
	}

	// Wraps the given content in a <form> tag
	static function form_wrap( $content, $nonce = 'update_options' ) {
		$output = "\n<form method='post' action=''>\n";
		$output .= $content;
		$output .= wp_nonce_field( $action = $nonce, $name = "_wpnonce", $referer = true , $echo = false );
		$output .= "\n</form>\n";

		return $output;
	}

	// Wraps the given content in a <table>
	static function table_wrap( $content ) {
		$output = "\n<table class='form-table'>\n" . $content . "\n</table>\n";

		return $output;
	}

	// Wraps the given content in a <tr><td>
	static function row_wrap( $title, $content ) {
		return "\n<tr>\n\t<th scope='row'>" . $title . "</th>\n\t<td>\n\t\t" . $content . "\t</td>\n\n</tr>";
	}


// ____________PRIVATE METHODS____________


	private static function _single_choice( $args ) {
		$args = wp_parse_args( $args, array(
			'numeric' => false,		// use numeric array instead of associative
			'selected' => array( 'foo' ),	// hack to make default blank
		) );

		self::_expand_values( $args );

		if ( 'select' == $args['type'] )
			return self::_select( $args );
		else
			return self::_radio( $args );
	}

	private static function _multiple_choice( $args ) {
		$args = wp_parse_args( $args, array(
			'numeric' => false,		// use numeric array instead of associative
			'checked' => null,
		) );

		self::$cur_name .= '[]';

		self::_expand_values( $args );

		extract( $args );

		if ( !is_array( $checked ) )
			$checked = array();

		$opts = '';
		foreach ( $value as $value => $title ) {
			if ( empty( $value ) || empty( $title ) )
				continue;

			$opts .= self::_checkbox( array(
				'type' => 'checkbox',
				'value' => $value,
				'checked' => in_array( $value, $checked ),
				'desc' => $title,
				'desc_pos' => $desc_pos
			) );
		}

		return $opts;
	}

	private static function _expand_values( &$args ) {
		$value =& $args['value'];

		if ( !empty( $value ) && !self::is_associative( $value ) ) {
			if ( is_array( $args['desc'] ) ) {
				$value = array_combine( $value, $args['desc'] );	// back-compat
			} elseif ( !$args['numeric'] ) {
				$value = array_combine( $value, $value );
			}
		}
	}

	private static function _radio( $args ) {
		extract( $args );

		if ( array( 'foo' ) == $selected ) {
			$selected = key( $value );	// radio buttons should always have one option selected
		}

		$opts = '';
		foreach ( $value as $value => $title ) {
			if ( empty( $value ) || empty( $title ) )
				continue;

			$opts .= self::_checkbox( array(
				'type' => 'radio',
				'value' => $value,
				'checked' => ( (string) $value == (string) $selected ),
				'desc' => $title,
				'desc_pos' => $desc_pos
			) );
		}

		return $opts;
	}

	private static function _select( $args ) {
		extract( wp_parse_args( $args, array(
			'text' => '',
			'extra' => array()
		) ) );

		$options = array();

		if ( false !== $text ) {
			$options[] = array(
				'value' => '',
				'selected' => ( $selected == array( 'foo' ) ),
				'title' => $text
			);
		}

		foreach ( $value as $value => $title ) {
			if ( empty( $value ) || empty( $title ) )
				continue;

			$options[] = array(
				'value' => $value,
				'selected' => ( (string) $value == (string) $selected ),
				'title' => $title
			);
		}

		$opts = '';
		foreach ( $options as $option ) {
			extract( $option );

			$opts .= html( 'option', compact( 'value', 'selected' ), $title );
		}

		$extra['name'] = self::$cur_name;

		$input = html( 'select', $extra, $opts );

		return self::add_label( $input, $desc, $desc_pos );
	}

	// Handle args for a single checkbox or radio input
	private static function _checkbox( $args ) {
		$args = wp_parse_args( $args, array(
			'value' => true,
			'desc' => NULL,
			'checked' => false,
			'extra' => array(),
		) );

		foreach ( $args as $key => &$val )
			$$key = &$val;
		unset( $val );

		$extra['checked'] = $checked;

		if ( is_null( $desc ) && !is_bool( $value ) )
			$desc = str_replace( '[]', '', $value );

		return self::_input_gen( $args );
	}

	// Handle args for text inputs
	private static function _input( $args ) {
		$args = wp_parse_args( $args, array(
			'value' => '',
			'desc_pos' => 'after',
			'extra' => array( 'class' => 'regular-text' ),
		) );

		foreach ( $args as $key => &$val )
			$$key = &$val;
		unset( $val );

		if ( !isset( $extra['id'] ) && !is_array( $name ) && false === strpos( $name, '[' ) )
			$extra['id'] = $name;

		return self::_input_gen( $args );
	}

	// Generate html with the final args
	private static function _input_gen( $args ) {
		extract( wp_parse_args( $args, array(
			'value' => NULL,
			'desc' => NULL,
			'extra' => array()
		) ) );

		$extra['name'] = self::$cur_name;

		if ( 'textarea' == $type ) {
			$input = html( 'textarea', $extra, esc_textarea( $value ) );
		} else {
			$extra['value'] = $value;
			$extra['type'] = $type;
			$input = html( 'input', $extra );
		}

		return self::add_label( $input, $desc, $desc_pos );
	}

	private static function add_label( $input, $desc, $desc_pos ) {
		if ( empty( $desc_pos ) )
			$desc_pos = 'after';

		$label = '';
		if ( false === strpos( $desc, self::token ) ) {
			switch ( $desc_pos ) {
				case 'before': $label = $desc . ' ' . self::token; break;
				case 'after': $label = self::token . ' ' . $desc;
			}
		} else {
			$label = $desc;
		}

		$label = trim( str_replace( self::token, $input, $label ) );

		if ( empty( $desc ) )
			$output = $input;
		else
			$output = html( 'label', $label );

		return $output . "\n";
	}


// Utilities


	/**
	 * Generates the proper string for a name attribute.
	 *
	 * @param array|string $name The raw name
	 *
	 * @return string
	 */
	static function get_name( $name ) {
		$name = (array) $name;

		$name_str = array_shift( $name );

		foreach ( $name as $key ) {
			$name_str .= '[' . esc_attr( $key ) . ']';
		}

		return $name_str;
	}

	/**
	 * Traverses the formdata and retrieves the correct value.
	 *
	 * @param array|string $name The name of the value
	 * @param array $value The data that will be traversed
	 *
	 * @return mixed
	 */
	static function get_value( $name, $value ) {
		foreach ( (array) $name as $key ) {
			if ( !isset( $value[ $key ] ) )
				return null;

			$value = $value[$key];
		}

		return $value;
	}

	private static function is_associative( $array ) {
		$keys = array_keys( $array );
		return array_keys( $keys ) !== $keys;
	}
}

/**
 * A wrapper for scbForms, containing the formdata
 */
class scbForm {
	protected $data = array();
	protected $prefix = array();

	function __construct( $data, $prefix = false ) {
		if ( is_array( $data ) )
			$this->data = $data;

		if ( $prefix )
			$this->prefix = (array) $prefix;
	}

	function traverse_to( $path ) {
		$data = scbForms::get_value( $path, $this->data );

		$prefix = array_merge( $this->prefix, (array) $path );

		return new scbForm( $data, $prefix );
	}

	function input( $args ) {
		$value = scbForms::get_value( $args['name'], $this->data );

		if ( !is_null( $value ) ) {
			switch ( $args['type'] ) {
			case 'select':
			case 'radio':
				$args['selected'] = $value;
				break;
			case 'checkbox':
				if ( is_array( $value ) )
					$args['checked'] = $value;
				else
					$args['checked'] = ( $value || ( isset( $args['value'] ) && $value == $args['value'] ) );
				break;
			default:
				$args['value'] = $value;
			}
		}

		if ( !empty( $this->prefix ) ) {
			$args['name'] = array_merge( $this->prefix, (array) $args['name'] );
		}

		return scbForms::input( $args );
	}
}