webAdministracion/processes/deleteQuestion.php

<?php

	require_once 'config.php';
	require_once 'dbh.inc.php';
	require_once 'checkLogin.php';
	
	
	// EXAMPLE INPUT...
	// array(2) { ["questionID"]=> string(3) "267" ["deleteQuestion"]=> string(0) "" }
	
	// WARNING: SHOULD CONFIRM THAT QUESTION BELONGS TO THE CORRECT USER (AUTHENTICATE THE TRANSACTION)
	// WARNING: IF USER DELETES ALL QUESTIONS FROM A QUESTIONNAIRE USING THIS METHOD, THE DATABASE WILL HAVE UNUSED CATEGORIES/SUBCATEGORIES, AS THEY ARE NOT ASSOCIATED DIRECTLY TO THE QUESTIONNAIRE
	
// 	var_dump($_POST);
// 	exit();


	if(isset($_POST['deleteQuestion'])) {
		


		$questionID = mysqli_real_escape_string($connection, trim($_POST['questionID']));
		
		
		// Check that question ID is not empty string
		if($questionID === "") {
			http_response_code(400);
			echo json_encode(array("error" => "Please specify question ID."));
			exit();
		}
		
		
		// Check that question is registered in the database
		if(mysqli_query($connection, "SELECT * FROM question WHERE id = '$questionID';")->num_rows !== 1) {
			http_response_code(400);
			echo json_encode(array("error" => "Given question ID ($questionID) not in database."));
			exit();
		}
		
		
		// Check that question hasn't been answered yet
		if(mysqli_query($connection, "SELECT * FROM answer WHERE id_question = '$questionID';")->num_rows !== 0) {
			http_response_code(400);
			echo json_encode(array("error" => "Question has already been answered by one or more people, deletion denied."));
			exit();
		}
		
		
		
		/*** STEPS ***/

		// DELETE MOMENT-QUESTION RELATION
		// DELETE QUESTIONNAIRE-QUESTION RELATION
		// DELETE QUESTION-TYPES
		// DELETE QUESTION


		
		// Delete moment-question relation
		$queryUnhookQuestionFromMoment = "DELETE FROM subquestionnair_question WHERE id_question = '$questionID';";
		$result = mysqli_query($connection, $queryUnhookQuestionFromMoment) or die("Error: ".mysqli_error($connection));

		// Delete questionnaire-question relation
		$queryUnhookQuestionFromQuestionnaire = "DELETE FROM questionnair_question WHERE id_question = '$questionID';";
		$result = mysqli_query($connection, $queryUnhookQuestionFromQuestionnaire) or die("Error: ".mysqli_error($connection));
	
		// Delete question types
		$queryDeleteQuestionTypes = "DELETE FROM question_type WHERE id_question = '$questionID';";
		$result = mysqli_query($connection, $queryDeleteQuestionTypes) or die("Error: ".mysqli_error($connection));

		// Delete question
		$queryDeleteQuestion = "DELETE FROM question WHERE id = '$questionID';";
		$result = mysqli_query($connection, $queryDeleteQuestion) or die("Error: ".mysqli_error($connection));
	
		
	
	}