pics/models/Form.php

<?php
/*****************************************************************************
 * Form.php
 * Contains key class Form.
 *
 * Global Data Lab code (C) Radboud University Nijmegen
 * Programming (C) Aaron van Geffen, 2015-2022
 *****************************************************************************/

class Form
{
	public $request_method;
	public $request_url;
	public $content_above;
	public $content_below;
	private $fields = [];
	private $data = [];
	private $missing = [];
	private $submit_caption;
	private $trim_inputs;

	// NOTE: this class does not verify the completeness of form options.
	public function __construct($options)
	{
		$this->request_method = !empty($options['request_method']) ? $options['request_method'] : 'POST';
		$this->request_url = !empty($options['request_url']) ? $options['request_url'] : BASEURL;
		$this->fields = !empty($options['fields']) ? $options['fields'] : [];
		$this->content_below = !empty($options['content_below']) ? $options['content_below'] : null;
		$this->content_above = !empty($options['content_above']) ? $options['content_above'] : null;
		$this->submit_caption = !empty($options['submit_caption']) ? $options['submit_caption'] : 'Save information';
		$this->trim_inputs = !empty($options['trim_inputs']);
	}

	public function getFields()
	{
		return $this->fields;
	}

	public function getData()
	{
		return $this->data;
	}

	public function getSubmitButtonCaption()
	{
		return $this->submit_caption;
	}

	public function getMissing()
	{
		return $this->missing;
	}

	public function setData($data)
	{
		$this->verify($data, true);
		$this->missing = [];
	}

	public function setFieldAsMissing($field)
	{
		$this->missing[] = $field;
	}

	public function verify($post, $initalisation = false)
	{
		$this->data = [];
		$this->missing = [];

		foreach ($this->fields as $field_id => $field)
		{
			// Field disabled?
			if (!empty($field['disabled']))
			{
				$this->data[$field_id] = '';
				continue;
			}

			// No data present at all for this field?
			if ((!isset($post[$field_id]) || $post[$field_id] == '') &&
				$field['type'] !== 'captcha')
			{
				if (empty($field['is_optional']))
					$this->missing[] = $field_id;

				if ($field['type'] === 'select' && !empty($field['multiple']))
					$this->data[$field_id] = [];
				else
					$this->data[$field_id] = '';

				continue;
			}

			// Should we trim this?
			if ($this->trim_inputs && $field['type'] !== 'captcha' && empty($field['multiple']))
				$post[$field_id] = trim($post[$field_id]);

			// Using a custom validation function?
			if (isset($field['validate']) && is_callable($field['validate']))
			{
				// Validation functions can clean up the data if passed by reference
				$this->data[$field_id] = $post[$field_id];

				// Evaluate validation functions as boolean to see if data is missing
				if (!$field['validate']($post[$field_id]))
					$this->missing[] = $field_id;

				continue;
			}

			// Verify data by field type
			switch ($field['type'])
			{
				case 'select':
				case 'radio':
					$this->validateSelect($field_id, $field, $post);
					break;

				case 'checkbox':
					// Just give us a 'boolean' int for this one
					$this->data[$field_id] = empty($post[$field_id]) ? 0 : 1;
					break;

				case 'color':
					$this->validateColor($field_id, $field, $post);
					break;

				case 'file':
					// Asset needs to be processed out of POST! This is just a filename.
					$this->data[$field_id] = isset($post[$field_id]) ? $post[$field_id] : '';
					break;

				case 'numeric':
					$this->validateNumeric($field_id, $field, $post);
					break;

				case 'captcha':
					if (isset($_POST['g-recaptcha-response']) && !$initalisation)
						$this->validateCaptcha($field_id);
					elseif (!$initalisation)
					{
						$this->missing[] = $field_id;
						$this->data[$field_id] = 0;
					}
					break;

				case 'text':
				case 'textarea':
				default:
					$this->validateText($field_id, $field, $post);
			}
		}
	}

	private function validateCaptcha($field_id)
	{
		$postdata = http_build_query([
			'secret' => RECAPTCHA_API_SECRET,
			'response' => $_POST['g-recaptcha-response'],
		]);

		$opts = [
			'http' => [
				'method'  => 'POST',
				'header'  => 'Content-type: application/x-www-form-urlencoded',
				'content' => $postdata,
			]
		];

		$context  = stream_context_create($opts);
		$result = file_get_contents('https://www.google.com/recaptcha/api/siteverify', false, $context);
		$check = json_decode($result);

		if ($check->success)
		{
			$this->data[$field_id] = 1;
		}
		else
		{
			$this->data[$field_id] = 0;
			$this->missing[] = $field_id;
		}
	}

	private function validateColor($field_id, array $field, array $post)
	{
		// Colors are stored as a string of length 3 or 6 (hex)
		if (!isset($post[$field_id]) || (strlen($post[$field_id]) != 3 && strlen($post[$field_id]) != 6))
		{
			$this->missing[] = $field_id;
			$this->data[$field_id] = '';
		}
		else
			$this->data[$field_id] = $post[$field_id];
	}

	private function validateNumeric($field_id, array $field, array $post)
	{
		$data = isset($post[$field_id]) ? $post[$field_id] : '';

		// Sanity check: does this even look numeric?
		if (!is_numeric($data))
		{
			$this->missing[] = $field_id;
			$this->data[$field_id] = 0;
			return;
		}

		// Do we need to a minimum bound?
		if (isset($field['min_value']))
		{
			if (is_float($field['min_value']) && (float) $data < $field['min_value'])
			{
				$this->missing[] = $field_id;
				$this->data[$field_id] = 0.0;
			}
			elseif (is_int($field['min_value']) && (int) $data < $field['min_value'])
			{
				$this->missing[] = $field_id;
				$this->data[$field_id] = 0;
			}
		}

		// What about a maximum bound?
		if (isset($field['max_value']))
		{
			if (is_float($field['max_value']) && (float) $data > $field['max_value'])
			{
				$this->missing[] = $field_id;
				$this->data[$field_id] = 0.0;
			}
			elseif (is_int($field['max_value']) && (int) $data > $field['max_value'])
			{
				$this->missing[] = $field_id;
				$this->data[$field_id] = 0;
			}
		}

		$this->data[$field_id] = $data;
	}

	private function validateSelect($field_id, array $field, array $post)
	{
		// Skip validation? Dangerous territory!
		if (isset($field['verify_options']) && $field['verify_options'] === false)
		{
			$this->data[$field_id] = $post[$field_id];
			return;
		}

		// Check whether selected option is valid.
		if (($field['type'] !== 'select' || empty($field['multiple'])) && empty($field['has_groups']))
		{
			if (isset($post[$field_id]) && !isset($field['options'][$post[$field_id]]))
			{
				$this->missing[] = $field_id;
				$this->data[$field_id] = '';
				return;
			}
			else
				$this->data[$field_id] = $post[$field_id];
		}
		// Multiple selections involve a bit more work.
		elseif (!empty($field['multiple']) && empty($field['has_groups']))
		{
			$this->data[$field_id] = [];
			if (!is_array($post[$field_id]))
			{
				if (isset($field['options'][$post[$field_id]]))
					$this->data[$field_id][] = $post[$field_id];
				else
					$this->missing[] = $field_id;
				return;
			}

			foreach ($post[$field_id] as $option)
			{
				if (isset($field['options'][$option]))
					$this->data[$field_id][] = $option;
			}

			if (empty($this->data[$field_id]))
				$this->missing[] = $field_id;
		}
		// Any optgroups involved?
		elseif (!empty($field['has_groups']))
		{
			if (!isset($post[$field_id]))
			{
				$this->missing[] = $field_id;
				$this->data[$field_id] = '';
				return;
			}

			// Expensive: iterate over all groups until the value selected has been found.
			foreach ($field['options'] as $label => $options)
			{
				if (is_array($options))
				{
					// Consider each of the options as a valid a value.
					foreach ($options as $value => $label)
					{
						if ($post[$field_id] === $value)
						{
							$this->data[$field_id] = $options;
							return;
						}
					}
				}
				else
				{
					// This is an ungrouped value in disguise! Treat it as such.
					if ($post[$field_id] === $options)
					{
						$this->data[$field_id] = $options;
						return;
					}
					else
						continue;
				}
			}

			// If we've reached this point, we'll consider the data invalid.
			$this->missing[] = $field_id;
			$this->data[$field_id] = '';
		}
		else
		{
			throw new UnexpectedValueException('Unexpected field configuration in validateSelect!');
		}
	}

	private function validateText($field_id, array $field, array $post)
	{
		$this->data[$field_id] = isset($post[$field_id]) ? $post[$field_id] : '';

		// Trim leading and trailing whitespace?
		if (!empty($field['trim']))
			$this->data[$field_id] = trim($this->data[$field_id]);

		// Is there a length limit to enforce?
		if (isset($field['maxlength']) && strlen($post[$field_id]) > $field['maxlength']) {
			$post[$field_id] = substr($post[$field_id], 0, $field['maxlength']);
		}
	}
}