<?php
/* For licensing terms, see /license.txt */

/**
 * @package chamilo.webservices
 */
require_once(dirname(__FILE__).'/../inc/global.inc.php');
$libpath = api_get_path(LIBRARY_PATH);
require_once(dirname(__FILE__).'/webservice.php');

/**
 * Web services available for the Session module. This class extends the WS class
 */
class WSSession extends WS
{

	/**
	 * Creates a session (helper method)
	 *
	 * @param string Name of the session
	 * @param string Start date, use the 'YYYY-MM-DD' format
	 * @param string End date, use the 'YYYY-MM-DD' format
	 * @param int Access delays of the coach (days before)
	 * @param int Access delays of the coach (days after)
	 * @param int Nolimit (0 = no limit of time, 1 = limit of time)
	 * @param int Visibility
	 * @param string User id field name for the coach
	 * @param string User id value for the coach
	 * @param string Original session id field name (use "chamilo_session_id" to use internal id)
	 * @param string Original session id value
	 * @param array Array of extra fields
	 * @return mixed Generated id in case of success, WSError otherwise
	 */
	protected function createSessionHelper(
		$name,
		$start_date,
		$end_date,
		$nb_days_access_before,
		$nb_days_access_after,
		$nolimit,
		$visibility,
		$user_id_field_name,
		$user_id_value,
		$session_id_field_name,
		$session_id_value,
		$extras
	) {
		// Verify that coach exists and get its id
		$user_id = $this->getUserId($user_id_field_name, $user_id_value);
		if ($user_id instanceof WSError) {
			return $user_id;
		}

		$coachStartDate = null;
		if (!empty($nb_days_access_before)) {
			$day = intval($nb_days_access_before);
			$coachStartDate = date('Y-m-d ', strtotime($start_date. ' + '.$day.' days'));
		}

		$coachEndDate = null;
		if (!empty($nb_days_access_after)) {
			$day = intval($nb_days_access_after);
			$coachEndDate = date('Y-m-d ', strtotime($end_date. ' + '.$day.' days'));
		}

		// Try to create the session
		$session_id = SessionManager::create_session(
			$name,
			$start_date,
			$end_date,
			$start_date,
			$end_date,
			$coachStartDate,
			$coachEndDate,
			$user_id,
			0,
			$visibility
		);
		if(!is_int($session_id)) {
			return new WSError(301, 'Could not create the session');
		} else {
			// Add the Original session id to the extra fields
			$extras_associative = array();
			if($session_id_field_name != "chamilo_session_id") {
				$extras_associative[$session_id_field_name] = $session_id_value;
			}
			foreach($extras as $extra) {
				$extras_associative[$extra['field_name']] = $extra['field_value'];
			}
			// Create the extra fields
			foreach($extras_associative as $fname => $fvalue) {
				SessionManager::create_session_extra_field($fname, 1, $fname);
				SessionManager::update_session_extra_field_value(
					$session_id,
					$fname,
					$fvalue
				);
			}
			return $session_id;
		}
	}

	/**
	 * Creates a session
	 *
	 * @param string API secret key
	 * @param string Name of the session
	 * @param string Start date, use the 'YYYY-MM-DD' format
	 * @param string End date, use the 'YYYY-MM-DD' format
	 * @param int Access delays of the coach (days before)
	 * @param int Access delays of the coach (days after)
	 * @param int Nolimit (0 = no limit of time, 1 = limit of time)
	 * @param int Visibility
	 * @param string User id field name for the coach
	 * @param string User id value for the coach
	 * @param string Original session id field name (use "chamilo_session_id" to use internal id)
	 * @param string Original session id value
	 * @param array Array of extra fields
	 * @return int Session id generated
	 */
	public function CreateSession($secret_key, $name, $start_date, $end_date, $nb_days_access_before, $nb_days_access_after, $nolimit, $visibility, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $extras) {
		$verifKey = $this->verifyKey($secret_key);
		if($verifKey instanceof WSError) {
			$this->handleError($verifKey);
		} else {
			$session_id = $this->createSessionHelper($name, $start_date, $end_date, $nb_days_access_before, $nb_days_access_after, $nolimit, $visibility, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $extras);
			if($session_id instanceof WSError) {
				$this->handleError($session_id);
			} else {
				return $session_id;
			}
		}
	}

	/**
	 * Deletes a session (helper method)
	 *
	 * @param string Session id field name
	 * @param string Session id value
	 * @return mixed True in case of success, WSError otherwise
	 */
	protected function deleteSessionHelper($session_id_field_name, $session_id_value) {
		$session_id = $this->getSessionId($session_id_field_name, $session_id_value);
		if($session_id instanceof WSError) {
			return $session_id;
		} else {
			SessionManager::delete($session_id, true);
			return true;
		}
	}

	/**
	 * Deletes a session
	 *
	 * @param string API secret key
	 * @param string Session id field name
	 * @param string Session id value
	 */
	public function DeleteSession($secret_key, $session_id_field_name, $session_id_value) {
		$verifKey = $this->verifyKey($secret_key);
		if($verifKey instanceof WSError) {
			$this->handleError($verifKey);
		} else {
			$result = $this->deleteSessionHelper($session_id_field_name, $session_id_value);
			if($result instanceof WSError) {
				$this->handleError($result);
			}
		}
	}

	/**
	 * Edits a session (helper method)
	 *
	 * @param string Name of the session
	 * @param string Start date, use the 'YYYY-MM-DD' format
	 * @param string End date, use the 'YYYY-MM-DD' format
	 * @param int Access delays of the coach (days before)
	 * @param int Access delays of the coach (days after)
	 * @param int Nolimit (0 = no limit of time, 1 = limit of time)
	 * @param int Visibility
	 * @param string User id field name for the coach
	 * @param string User id value for the coach
	 * @param string Original session id field name (use "chamilo_session_id" to use internal id)
	 * @param string Original session id value
	 * @param array Array of extra fields
	 * @return mixed True on success, WSError otherwise
	 */
    protected function editSessionHelper(
        $name,
        $start_date,
        $end_date,
        $nb_days_access_before,
        $nb_days_access_after,
        $nolimit,
        $visibility,
        $user_id_field_name,
        $user_id_value,
        $session_id_field_name,
        $session_id_value,
        $extras
    ) {
		$session_id = $this->getSessionId($session_id_field_name, $session_id_value);
		if($session_id instanceof WSError) {
			return $session_id;
		} else {
			// Verify that coach exists and get its id
			$user_id = $this->getUserId($user_id_field_name, $user_id_value);
			if ($user_id instanceof WSError) {
				return $user_id;
			}

            $coachStartDate = null;
            if (!empty($nb_days_access_before)) {
                $day = intval($nb_days_access_before);
                $coachStartDate = date('Y-m-d ', strtotime($start_date. ' + '.$day.' days'));
            }

            $coachEndDate = null;
            if (!empty($nb_days_access_after)) {
                $day = intval($nb_days_access_after);
                $coachEndDate = date('Y-m-d ', strtotime($end_date. ' + '.$day.' days'));
            }

            $result_id = SessionManager::edit_session(
                $session_id,
                $name,
                $start_date,
                $end_date,
                $start_date,
                $end_date,
                $coachStartDate,
                $coachEndDate,
                $user_id,
                0,
                (int)$visibility
            );
			if(!is_int($result_id)) {
				return new WSError(302, 'Could not edit the session');
			} else {
				if(!empty($extras)) {
					$extras_associative = array();
					foreach($extras as $extra) {
						$extras_associative[$extra['field_name']] = $extra['field_value'];
					}
					// Create the extra fields
					foreach($extras_associative as $fname => $fvalue) {
						SessionManager::create_session_extra_field($fname, 1, $fname);
						SessionManager::update_session_extra_field_value($session_id, $fname, $fvalue);
					}
				}
				return true;
			}
		}
	}

	/**
	 * Edits a session
	 *
	 * @param string API secret key
	 * @param string Name of the session
	 * @param string Start date, use the 'YYYY-MM-DD' format
	 * @param string End date, use the 'YYYY-MM-DD' format
	 * @param int Access delays of the coach (days before)
	 * @param int Access delays of the coach (days after)
	 * @param int Nolimit (0 = no limit of time, 1 = limit of time)
	 * @param int Visibility
	 * @param string User id field name for the coach
	 * @param string User id value for the coach
	 * @param string Original session id field name (use "chamilo_session_id" to use internal id)
	 * @param string Original session id value
	 * @param array Array of extra fields
	 */
	public function EditSession($secret_key, $name, $start_date, $end_date, $nb_days_access_before, $nb_days_access_after, $nolimit, $visibility, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $extras) {
		$verifKey = $this->verifyKey($secret_key);
		if($verifKey instanceof WSError) {
			$this->handleError($verifKey);
		} else {
			$result = $this->editSessionHelper($name, $start_date, $end_date, $nb_days_access_before, $nb_days_access_after, $nolimit, $visibility, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $extras);
			if($session_id_value instanceof WSError) {
				$this->handleError($result);
			}
		}
	}

	/**
	 * Change user subscription (helper method)
	 *
	 * @param string User id field name
	 * @param string User id value
	 * @param string Session id field name
	 * @param string Session id value
	 * @param int State (1 to subscribe, 0 to unsubscribe)
	 * @return mixed True on success, WSError otherwise
	 */
	protected function changeUserSubscription($user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $state) {
		$session_id = $this->getSessionId($session_id_field_name, $session_id_value);
		if($session_id instanceof WSError) {
			return $session_id;
		} else {
			$user_id = $this->getUserId($user_id_field_name, $user_id_value);
			if($user_id instanceof WSError) {
				return $user_id;
			} else {
				if($state  == 1) {
					SessionManager::suscribe_users_to_session($session_id, array($user_id));
				} else {
					$result = SessionManager::unsubscribe_user_from_session($session_id, $user_id);
					if (!$result) {
						return new WSError(303, 'There was an error unsubscribing this user from the session');
					}
				}
				return true;
			}
		}
	}

	/**
	 * Subscribe user to a session
	 *
	 * @param string API secret key
	 * @param string User id field name
	 * @param string User id value
	 * @param string Session id field name
	 * @param string Session id value
	 */
	public function SubscribeUserToSession($secret_key, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value) {
		$verifKey = $this->verifyKey($secret_key);
		if($verifKey instanceof WSError) {
			$this->handleError($verifKey);
		} else {
			$result = $this->changeUserSubscription($user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, 1);
			if($result instanceof WSError) {
				$this->handleError($result);
			}
		}
	}

	/**
	 * Subscribe user to a session
	 *
	 * @param string API secret key
	 * @param string User id field name
	 * @param string User id value
	 * @param string Session id field name
	 * @param string Session id value
	 */
	public function UnsubscribeUserFromSession($secret_key, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value) {
		$verifKey = $this->verifyKey($secret_key);
		if($verifKey instanceof WSError) {
			$this->handleError($verifKey);
		} else {
			$result = $this->changeUserSubscription($user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, 0);
			if($result instanceof WSError) {
				$this->handleError($result);
			}
		}
	}
    
    /**
     * Change Teacher subscription (helper method)
     *
     * @param string User id field name
     * @param string User id value
     * @param string Session id field name
     * @param string Session id value
     * @param string Course id field name
     * @param string Course id value
     * @param int State (1 to subscribe, 0 to unsubscribe)
     * @return mixed True on success, WSError otherwise
     */
    protected function changeTeacherSubscription($user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $course_id_field_name, $course_id_value, $state)
    {
        $session_id = $this->getSessionId($session_id_field_name, $session_id_value);
        if ($session_id instanceof WSError) {
            return $session_id;
        } else {
            $user_id = $this->getUserId($user_id_field_name, $user_id_value);
            if ($user_id instanceof WSError) {
                return $user_id;
            } else {
                $course_id = $this->getCourseId($course_id_field_name, $course_id_value);
                if ($course_id instanceof WSError) {
                    return $course_id;
                } else {
                    if ($state == 1) {
                        SessionManager::set_coach_to_course_session($user_id, $session_id, $course_id);
                    } else {
                        $user_id = array (0 => $user_id);
                        $result = SessionManager::removeUsersFromCourseSession($user_id, $session_id, $course_id);
                        if (!$result) {
                            return new WSError(303, 'There was an error unsubscribing this Teacher from the session');
                        }
                    }
                    return true;
                }
            }
        }
    }

    /**
     * Subscribe teacher to a session course
     *
     * @param string API secret key
     * @param string User id field name
     * @param string User id value
     * @param string Session id field name
     * @param string Session id value
     * @param string Course id field name
     * @param string Course id value
     */
    public function SubscribeTeacherToSessionCourse($secret_key, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $course_id_field_name, $course_id_value)
    {
        $verifKey = $this->verifyKey($secret_key);
        if ($verifKey instanceof WSError) {
            $this->handleError($verifKey);
        } else {
            $result = $this->changeUserSubscription($user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $course_id_field_name, $course_id_value, 1);
            if ($result instanceof WSError) {
                $this->handleError($result);
            }
        }
    }

    /**
     * Subscribe teacher to a session course
     *
     * @param string API secret key
     * @param string User id field name
     * @param string User id value
     * @param string Session id field name
     * @param string Session id value
     * @param string Course id field name
     * @param string Course id value
     */
    public function UnsubscribeTeacherFromSessionCourse($secret_key, $user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $course_id_field_name, $course_id_value)
    {
        $verifKey = $this->verifyKey($secret_key);
        if ($verifKey instanceof WSError) {
            $this->handleError($verifKey);
        } else {
            $result = $this->changeUserSubscription($user_id_field_name, $user_id_value, $session_id_field_name, $session_id_value, $course_id_field_name, $course_id_value, 0);
            if ($result instanceof WSError) {
                $this->handleError($result);
            }
        }
    }

    /**
	 * Change course subscription
	 *
	 * @param string Course id field name
	 * @param string Course id value
	 * @param string Session id field name
	 * @param string Session id value
	 * @param int State (1 to subscribe, 0 to unsubscribe)
	 * @return mixed True on success, WSError otherwise
	 */
	protected function changeCourseSubscription($course_id_field_name, $course_id_value, $session_id_field_name, $session_id_value, $state) {
		$session_id = $this->getSessionId($session_id_field_name, $session_id_value);
		if($session_id instanceof WSError) {
			return $session_id;
		} else {
			$course_id = $this->getCourseId($course_id_field_name, $course_id_value);
			if($course_id instanceof WSError) {
				return $course_id;
			} else {
				if($state  == 1) {
					SessionManager::add_courses_to_session($session_id, array($course_id));
					return true;
				} else {
					$result = SessionManager::unsubscribe_course_from_session($session_id, $course_id);
					if ($result) {
						return true;
					} else {
						return new WSError(304, 'Error unsubscribing course from session');
					}
				}
			}
		}
    }

	/**
	 * Subscribe course to session
	 *
	 * @param string API secret key
	 * @param string Course id field name
	 * @param string Course id value
	 * @param string Session id field name
	 * @param string Session id value
	 */
	public function SubscribeCourseToSession($secret_key, $course_id_field_name, $course_id_value, $session_id_field_name, $session_id_value) {
		$verifKey = $this->verifyKey($secret_key);
		if($verifKey instanceof WSError) {
			$this->handleError($verifKey);
		} else {
			$result = $this->changeCourseSubscription($course_id_field_name, $course_id_value, $session_id_field_name, $session_id_value, 1);
			if($result instanceof WSError) {
				$this->handleError($result);
			}
		}
	}

	/**
	 * Unsubscribe course from session
	 *
	 * @param string API secret key
	 * @param string Course id field name
	 * @param string Course id value
	 * @param string Session id field name
	 * @param string Session id value
	 */
	public function UnsubscribeCourseFromSession($secret_key, $course_id_field_name, $course_id_value, $session_id_field_name, $session_id_value) {
		$verifKey = $this->verifyKey($secret_key);
		if($verifKey instanceof WSError) {
			$this->handleError($verifKey);
		} else {
			$result = $this->changeCourseSubscription($course_id_field_name, $course_id_value, $session_id_field_name, $session_id_value, 0);
			if($result instanceof WSError) {
				$this->handleError($result);
			}
		}
	}

}