<?php

/**

 * Common functions to manipulate with the quiz

 */



if ( !defined( 'ABSPATH' ) ) {

	exit; // Exit if accessed directly

}



/**

 * Get all questions of a quiz

 *

 * @author  TuNN

 *

 * @param   int     $quiz_id  The ID of a quiz to get all questions

 * @param   boolean $only_ids return an array of questions with IDs only or as post objects

 *

 * @return  array|null

 */

function learn_press_get_quiz_questions( $quiz_id = null, $only_ids = true ) {

	if ( !$quiz_id ) {

		$quiz_id = get_the_ID();

	}

	return ( $quiz = LP_Quiz::get_quiz( $quiz_id ) ) ? $quiz->get_questions() : false;

}





function learn_press_question_class( $question = null, $args = array() /*, $classes = null, $user_id = null, $context = null*/ ) {

	$args    = wp_parse_args(

		$args,

		array(

			'user'    => LP()->user,

			'quiz'    => LP()->quiz,

			'classes' => ''

		)

	);

	$quiz    = $args['quiz'];

	$user    = $args['user'];

	$classes = $args['classes'];





	if ( !$question ) {

		$question = LP_Question_Factory::get_question( get_the_ID() );

	} elseif ( is_numeric( $question ) ) {

		$question = LP_Question_Factory::get_question( $question );

	}

	if ( $question ) {

		if ( is_string( $classes ) ) {

			$classes = explode( ' ', $classes );

		}

		settype( $classes, 'array' );

		$classes = array_merge( $classes, array( "learn-press-question-wrap", "question-type-{$question->type}", "question-{$question->id}" ) );

		$status  = $user->get_quiz_status( $quiz->id );

		if ( $status == 'completed' ) {

			$user_id     = learn_press_get_current_user_id();

			$user        = learn_press_get_user( $user_id );

			$answer_data = $user->get_answer_results( $question->id, $quiz->id );

			$classes[]   = 'question-results';

			if ( $user->is_answered_question( $question->id, $quiz->id ) ) {

				if ( $answer_data['correct'] ) {

					$classes[] = 'correct';

				} else {

					$classes[] = 'incorrect';

				}

			} else {

				$classes[] = 'skipped';

			}

		} else if ( $status == 'started' && $question->id == learn_press_get_request( 'question' ) ) {

			$classes[] = 'current';

		}



		$classes = apply_filters( 'learn_press_question_class', $classes, $question, $quiz );

		$classes = array_unique( $classes );

		$classes = array_filter( $classes );

		echo "class=\"" . join( ' ', $classes ) . "\"";

	}

}



function learn_press_get_user_quiz_meta( $quiz_user_id, $meta_key, $single = true ) {

	return get_metadata( 'learnpress_user_quiz', $quiz_user_id, $meta_key, $single );

}



function learn_press_add_user_quiz_meta( $quiz_user_id, $meta_key, $meta_value, $prev_value = '' ) {

	return add_metadata( 'learnpress_user_quiz', $quiz_user_id, $meta_key, $meta_value, $prev_value );

}



function learn_press_update_user_quiz_meta( $quiz_user_id, $meta_key, $meta_value, $prev_value = '' ) {

	return update_metadata( 'learnpress_user_quiz', $quiz_user_id, $meta_key, $meta_value, $prev_value );

}



/**

 * @param int

 * @param int - since 0.9.5

 *

 * @return bool|int

 */

function learn_press_get_current_question( $quiz_id = null, $user_id = 0 ) {

	if ( $user_id ) {

		$user = learn_press_get_user( $user_id );

	} else {

		$user = LP()->user;

	}

	return $user->get_current_question( $quiz_id );

}



/**

 * Check to see if user not passed the ID of quiz try to get it from global

 * Only works in single quiz page

 *

 * @param $id

 *

 * @return mixed

 */

function learn_press_get_quiz_id( $id ) {

	if ( !$id ) {

		global $quiz;

		$id = $quiz->id;

	}

	return $id;

}



/**

 * Check if user has completed a quiz or not

 *

 * @author  TuNN

 *

 * @param   int $user_id The ID of user need to check

 * @param   int $quiz_id The ID of quiz need to check

 *

 * @return  boolean

 */

function learn_press_user_has_completed_quiz( $user_id = null, $quiz_id = null ) {

	//_deprecated_function( __FUNCTION__, '1.0', 'LP_User() -> has_completed_quiz' );



	if ( $user = learn_press_get_user( $user_id ) ) {

		return $user->has_completed_quiz( $quiz_id );

	}

	return false;

}



/**

 * get the time remaining of a quiz has started by an user

 *

 * @param null $user_id

 * @param null $quiz_id

 *

 * @return int

 */

function learn_press_get_quiz_time_remaining( $user_id = null, $quiz_id = null ) {

	global $quiz;

	if ( !$user_id ) $user_id = get_current_user_id();

	$quiz_id = $quiz_id ? $quiz_id : ( $quiz ? $quiz->id : 0 );

	if ( !$quiz_id ) return 0;

	$meta            = get_user_meta( $user_id, '_lpr_quiz_start_time', true );

	$quiz_duration   = get_post_meta( $quiz_id, '_lpr_duration', true );

	$time_remaining  = $quiz_duration * 60;

	$quiz_start_time = !empty( $meta[$quiz_id] ) ? $meta[$quiz_id] : 0;

	$quiz_start_time = apply_filters( 'learn_press_user_quiz_start_time', $quiz_start_time, $quiz_id, $user_id );



	if ( $quiz_duration && learn_press_user_has_started_quiz( $user_id, $quiz_id ) ) {

		$quiz_duration *= 60;

		$now = current_time( 'timestamp' );



		if ( $now < $quiz_start_time + $quiz_duration ) {

			$time_remaining = $quiz_start_time + $quiz_duration - $now;

		} else {

			$time_remaining = 0;

		}



	}

	return apply_filters( 'learn_press_get_quiz_time_remaining', $time_remaining, $user_id, $quiz_id );

}



/*

 * Get question url in a quiz for user

 *

 * @param int the ID of a quiz

 * @param int the ID of question - default is current question of quiz user is doing

 * @param int the ID of user - default is current user

 *

 * @return string

 */

function learn_press_get_user_question_url( $quiz_id, $current_question_id = 0, $user_id = 0 ) {

	if ( !$current_question_id ) {

		$current_question_id = learn_press_get_current_question( $quiz_id, $user_id );

	}

	$permalink = get_the_permalink( $quiz_id );

	if ( $current_question_id && get_post_type( $current_question_id ) == 'lp_question' ) {

		$question_name = get_post_field( 'post_name', $current_question_id );

		if ( '' != get_option( 'permalink_structure' ) ) {

			$permalink .= $question_name;

		} else {

			$permalink = add_query_arg( 'question', $question_name, $permalink );

		}

	}

	$permalink = trailingslashit( $permalink );

	return apply_filters( 'learn_press_quiz_question_url', $permalink, $quiz_id, $current_question_id, $user_id );

}



/**

 * Check if user has started a quiz or not

 *

 * @param int $user_id

 * @param int $quiz_id

 *

 * @return boolean

 */

function learn_press_user_has_started_quiz( $user_id = null, $quiz_id = null ) {

	$user = $user_id ? learn_press_get_user( $user_id ) : LP()->user;

	return $user ? $user->has( 'started-quiz', $quiz_id ) : false;

}



/**

 * Get current status of a quiz for user

 * Status:

 *      - null => User does not start quiz

 *        - Started => User has started quiz

 *        - Completed => User has finished quiz

 *

 * @param            $quiz_id

 * @param bool|false $user_id

 *

 * @return string

 */

function learn_press_get_user_quiz_status( $quiz_id, $user_id = false ) {

	$user = $user_id ? learn_press_get_user( $user_id ) : LP()->user;

	return $user ? $user->get_quiz_status( $quiz_id ) : '';

}



/**

 * Redirect to question if user access to a quiz that user has started

 *

 * @param string

 *

 * @return string

 */

function learn_press_redirect_to_question( $template ) {

	global $post_type;

	if ( is_single() && $post_type == LP()->quiz_post_type ) {

		$user        = learn_press_get_current_user();

		$quiz_id     = get_the_ID();

		$quiz_status = $user->get_quiz_status( $quiz_id );

		if ( $quiz_status == 'started' && learn_press_get_quiz_time_remaining( $user->id, $quiz_id ) == 0 && get_post_meta( $quiz_id, '_lpr_duration', true ) ) {

			$user->finish_quiz( $quiz_id );

			$quiz_status = 'completed';

		}

		$redirect = null;

		if ( learn_press_get_request( 'question' ) && $quiz_status == '' ) {

			$redirect = get_the_permalink( $quiz_id );

		} elseif ( $quiz_status == 'started' ) {

			if ( learn_press_get_request( 'question' ) ) {

			} else {

				$redirect = learn_press_get_user_question_url( $quiz_id );

			}

		} elseif ( $quiz_status == 'completed' && learn_press_get_request( 'question' ) ) {

			$redirect = get_the_permalink( $quiz_id );

		}

		if ( $redirect && !learn_press_is_current_url( $redirect ) ) {

			wp_redirect( $redirect );

			exit();

		}

	}

	return $template;

}



//add_action( 'template_redirect', 'learn_press_redirect_to_question' );





function learn_press_get_quizzes( $user_id = 0, &$args = array() ) {

	if ( !$user_id ) {

		$user_id = learn_press_get_current_user_id();

	}

	if ( !$user_id ) {

		return;

	}

	$user = learn_press_get_user( $user_id );

	return $user->get_quizzes( $args );

}



function learn_press_output_question_nonce( $question ) {

	printf( '<input type="hidden" name="update-question-nonce" value="%s" />', wp_create_nonce( 'current-question-nonce-' . $question->id ) );

}



add_action( 'learn_press_after_question_wrap', 'learn_press_output_question_nonce' );



function learn_press_add_question_type_support( $types, $supports ) {

	if ( empty( $GLOBALS['learn_press_question_type_support'] ) ) {

		$GLOBALS['learn_press_question_type_support'] = array();

	}

	$_supports = $GLOBALS['learn_press_question_type_support'];

	settype( $types, 'array' );

	settype( $supports, 'array' );



	$types    = array_filter( $types );

	$supports = array_filter( $supports );



	if ( $types ) foreach ( $types as $type ) {

		if ( !$type ) {

			continue;

		}

		if ( empty( $_supports[$type] ) ) {

			$_supports[$type] = array();

		}

		if ( $supports ) foreach ( $supports as $s ) {

			$_supports[$type][] = $s;

		}

		$_supports[$type] = array_filter( $_supports[$type] );

	}

	$GLOBALS['learn_press_question_type_support'] = $_supports;

}



function learn_press_get_question_type_support( $type = '' ) {

	$supports = !empty( $GLOBALS['learn_press_question_type_support'] ) ? $GLOBALS['learn_press_question_type_support'] : array();

	return $type && !empty( $supports[$type] ) ? $supports[$type] : $supports;

}



function learn_press_question_type_support( $type, $features ) {

	settype( $features, 'array' );

	$features    = array_filter( $features );

	$supports    = learn_press_get_question_type_support( $type );

	$has_support = true;

	if ( $features ) {

		foreach ( $features as $feature ) {

			$has_support = $has_support && in_array( $feature, $supports );

		}

	}

	return $has_support;

}



function _learn_press_add_question_type_support() {

	learn_press_add_question_type_support(

		array(

			'multi_choice',

			'single_choice',

			'true_or_false'

		),

		'check-answer'

	);

}



add_action( 'plugins_loaded', '_learn_press_add_question_type_support' );