headless_lms_server/controllers/course_material/

exams.rs

use chrono::{DateTime, Duration, Utc};
use headless_lms_models::{CourseOrExamId, ModelError, ModelErrorType, exercises::Exercise};
use models::{
    exams::{self, ExamEnrollment},
    exercises,
    pages::{self, Page},
    teacher_grading_decisions::{self, TeacherGradingDecision},
    user_exercise_states,
};

use crate::prelude::*;

/**
GET /api/v0/course-material/exams/:id/enrollment
*/
#[instrument(skip(pool))]
pub async fn enrollment(
    pool: web::Data<PgPool>,
    exam_id: web::Path<Uuid>,
    user: AuthUser,
) -> ControllerResult<web::Json<Option<ExamEnrollment>>> {
    let mut conn = pool.acquire().await?;
    let enrollment = exams::get_enrollment(&mut conn, *exam_id, user.id).await?;
    let token = authorize(&mut conn, Act::Teach, Some(user.id), Res::Exam(*exam_id)).await?;
    token.authorized_ok(web::Json(enrollment))
}

#[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
#[cfg_attr(feature = "ts_rs", derive(TS))]
pub struct IsTeacherTesting {
    pub is_teacher_testing: bool,
}
/**
POST /api/v0/course-material/exams/:id/enroll
*/
#[instrument(skip(pool))]
pub async fn enroll(
    pool: web::Data<PgPool>,
    exam_id: web::Path<Uuid>,
    user: AuthUser,
    payload: web::Json<IsTeacherTesting>,
) -> ControllerResult<web::Json<()>> {
    let mut conn = pool.acquire().await?;
    let exam = exams::get(&mut conn, *exam_id).await?;

    // enroll if teacher is testing regardless of exams starting time
    if payload.is_teacher_testing {
        exams::enroll(&mut conn, *exam_id, user.id, payload.is_teacher_testing).await?;
        let token = authorize(&mut conn, Act::Edit, Some(user.id), Res::Exam(*exam_id)).await?;
        return token.authorized_ok(web::Json(()));
    }

    // check that the exam is not over
    let now = Utc::now();
    if exam.ended_at_or(now, false) {
        return Err(ControllerError::new(
            ControllerErrorType::Forbidden,
            "Exam is over".to_string(),
            None,
        ));
    }

    if exam.started_at_or(now, false) {
        // This check should probably be handled in the authorize function but I'm not sure of
        // the proper action type.
        let can_start =
            models::library::progressing::user_can_take_exam(&mut conn, *exam_id, user.id).await?;
        if !can_start {
            return Err(ControllerError::new(
                ControllerErrorType::Forbidden,
                "User is not allowed to enroll to the exam.".to_string(),
                None,
            ));
        }
        exams::enroll(&mut conn, *exam_id, user.id, payload.is_teacher_testing).await?;
        let token = skip_authorize();
        return token.authorized_ok(web::Json(()));
    }

    // no start time defined or it's still upcoming
    Err(ControllerError::new(
        ControllerErrorType::Forbidden,
        "Exam has not started yet".to_string(),
        None,
    ))
}

#[derive(Debug, Serialize)]
#[cfg_attr(feature = "ts_rs", derive(TS))]
pub struct ExamData {
    pub id: Uuid,
    pub name: String,
    pub instructions: serde_json::Value,
    pub starts_at: DateTime<Utc>,
    pub ends_at: DateTime<Utc>,
    pub ended: bool,
    pub time_minutes: i32,
    pub enrollment_data: ExamEnrollmentData,
    pub language: String,
}

#[derive(Debug, Serialize)]
#[cfg_attr(feature = "ts_rs", derive(TS))]
#[serde(tag = "tag")]
pub enum ExamEnrollmentData {
    /// The student has enrolled to the exam and started it.
    EnrolledAndStarted {
        page_id: Uuid,
        page: Box<Page>,
        enrollment: ExamEnrollment,
    },
    /// The student has not enrolled to the exam yet. However, the the exam is open.
    NotEnrolled { can_enroll: bool },
    /// The exam's start time is in the future, no one can enroll yet.
    NotYetStarted,
    /// The exam is still open but the student has run out of time.
    StudentTimeUp,
    // Exam is still open but student can view published grading results
    StudentCanViewGrading {
        gradings: Vec<(TeacherGradingDecision, Exercise)>,
        enrollment: ExamEnrollment,
    },
}

/**
GET /api/v0/course-material/exams/:id
*/
#[instrument(skip(pool))]
pub async fn fetch_exam_for_user(
    pool: web::Data<PgPool>,
    exam_id: web::Path<Uuid>,
    user: AuthUser,
) -> ControllerResult<web::Json<ExamData>> {
    let mut conn = pool.acquire().await?;
    let exam = exams::get(&mut conn, *exam_id).await?;

    let starts_at = if let Some(starts_at) = exam.starts_at {
        starts_at
    } else {
        return Err(ControllerError::new(
            ControllerErrorType::Forbidden,
            "Cannot fetch exam that has no start time".to_string(),
            None,
        ));
    };
    let ends_at = if let Some(ends_at) = exam.ends_at {
        ends_at
    } else {
        return Err(ControllerError::new(
            ControllerErrorType::Forbidden,
            "Cannot fetch exam that has no end time".to_string(),
            None,
        ));
    };

    let ended = ends_at < Utc::now();

    if starts_at > Utc::now() {
        // exam has not started yet
        let token = authorize(&mut conn, Act::View, Some(user.id), Res::Exam(*exam_id)).await?;
        return token.authorized_ok(web::Json(ExamData {
            id: exam.id,
            name: exam.name,
            instructions: exam.instructions,
            starts_at,
            ends_at,
            ended,
            time_minutes: exam.time_minutes,
            enrollment_data: ExamEnrollmentData::NotYetStarted,
            language: exam.language,
        }));
    }

    let enrollment = match exams::get_enrollment(&mut conn, *exam_id, user.id).await? {
        Some(enrollment) => {
            if exam.grade_manually {
                // Get the grading results, if the student has any
                let teachers_grading_decisions_list =
                teacher_grading_decisions::get_all_latest_grading_decisions_by_user_id_and_exam_id(
                    &mut conn, user.id, *exam_id,
                )
                .await?;
                let teacher_grading_decisions = teachers_grading_decisions_list.clone();

                let exam_exercises =
                    exercises::get_exercises_by_exam_id(&mut conn, *exam_id).await?;

                let user_exercise_states =
                    user_exercise_states::get_all_for_user_and_course_or_exam(
                        &mut conn,
                        user.id,
                        CourseOrExamId::Exam(*exam_id),
                    )
                    .await?;

                let mut grading_decision_and_exercise_list: Vec<(
                    TeacherGradingDecision,
                    Exercise,
                )> = Vec::new();

                // Check if student has any published grading results they can view at the exam page
                for grading_decision in teachers_grading_decisions_list.into_iter() {
                    if let Some(hidden) = grading_decision.hidden {
                        if !hidden {
                            // Get the corresponding exercise for the grading result
                            for grading in teacher_grading_decisions.into_iter() {
                                let user_exercise_state = user_exercise_states
                                    .iter()
                                    .find(|state| state.id == grading.user_exercise_state_id)
                                    .ok_or_else(|| {
                                        ModelError::new(
                                            ModelErrorType::Generic,
                                            "User_exercise_state not found",
                                            None,
                                        )
                                    })?;

                                let exercise = exam_exercises
                                    .iter()
                                    .find(|exercise| exercise.id == user_exercise_state.exercise_id)
                                    .ok_or_else(|| {
                                        ModelError::new(
                                            ModelErrorType::Generic,
                                            "Exercise not found",
                                            None,
                                        )
                                    })?;

                                grading_decision_and_exercise_list
                                    .push((grading, exercise.clone()));
                            }

                            let token =
                                authorize(&mut conn, Act::View, Some(user.id), Res::Exam(*exam_id))
                                    .await?;
                            return token.authorized_ok(web::Json(ExamData {
                                id: exam.id,
                                name: exam.name,
                                instructions: exam.instructions,
                                starts_at,
                                ends_at,
                                ended,
                                time_minutes: exam.time_minutes,
                                enrollment_data: ExamEnrollmentData::StudentCanViewGrading {
                                    gradings: grading_decision_and_exercise_list,
                                    enrollment,
                                },
                                language: exam.language,
                            }));
                        }
                    }
                }
                // user has ended the exam
                if enrollment.ended_at.is_some() {
                    let token: domain::authorization::AuthorizationToken =
                        authorize(&mut conn, Act::View, Some(user.id), Res::Exam(*exam_id)).await?;
                    return token.authorized_ok(web::Json(ExamData {
                        id: exam.id,
                        name: exam.name,
                        instructions: exam.instructions,
                        starts_at,
                        ends_at,
                        ended,
                        time_minutes: exam.time_minutes,
                        enrollment_data: ExamEnrollmentData::StudentTimeUp,
                        language: exam.language,
                    }));
                }
            }

            // user has started the exam
            if Utc::now() < ends_at
                && (Utc::now()
                    > enrollment.started_at + Duration::minutes(exam.time_minutes.into())
                    || enrollment.ended_at.is_some())
            {
                // exam is still open but the student's time has expired or student has ended their exam
                if enrollment.ended_at.is_none() {
                    exams::update_exam_ended_at(&mut conn, *exam_id, user.id, Utc::now()).await?;
                }
                let token: domain::authorization::AuthorizationToken =
                    authorize(&mut conn, Act::View, Some(user.id), Res::Exam(*exam_id)).await?;
                return token.authorized_ok(web::Json(ExamData {
                    id: exam.id,
                    name: exam.name,
                    instructions: exam.instructions,
                    starts_at,
                    ends_at,
                    ended,
                    time_minutes: exam.time_minutes,
                    enrollment_data: ExamEnrollmentData::StudentTimeUp,
                    language: exam.language,
                }));
            }
            enrollment
        }
        _ => {
            // user has not started the exam
            let token = authorize(&mut conn, Act::View, Some(user.id), Res::Exam(*exam_id)).await?;
            let can_enroll =
                models::library::progressing::user_can_take_exam(&mut conn, *exam_id, user.id)
                    .await?;
            return token.authorized_ok(web::Json(ExamData {
                id: exam.id,
                name: exam.name,
                instructions: exam.instructions,
                starts_at,
                ends_at,
                ended,
                time_minutes: exam.time_minutes,
                enrollment_data: ExamEnrollmentData::NotEnrolled { can_enroll },
                language: exam.language,
            }));
        }
    };

    let page = pages::get_page(&mut conn, exam.page_id).await?;

    let token = authorize(&mut conn, Act::View, Some(user.id), Res::Exam(*exam_id)).await?;
    token.authorized_ok(web::Json(ExamData {
        id: exam.id,
        name: exam.name,
        instructions: exam.instructions,
        starts_at,
        ends_at,
        ended,
        time_minutes: exam.time_minutes,
        enrollment_data: ExamEnrollmentData::EnrolledAndStarted {
            page_id: exam.page_id,
            page: Box::new(page),
            enrollment,
        },
        language: exam.language,
    }))
}

/**
GET /api/v0/course-material/exams/:id/fetch-exam-for-testing

Fetches an exam for testing.
*/
#[instrument(skip(pool))]
pub async fn fetch_exam_for_testing(
    pool: web::Data<PgPool>,
    exam_id: web::Path<Uuid>,
    user: AuthUser,
) -> ControllerResult<web::Json<ExamData>> {
    let mut conn = pool.acquire().await?;
    let exam = exams::get(&mut conn, *exam_id).await?;

    let starts_at = Utc::now();
    let ends_at = if let Some(ends_at) = exam.ends_at {
        ends_at
    } else {
        return Err(ControllerError::new(
            ControllerErrorType::Forbidden,
            "Cannot fetch exam that has no end time".to_string(),
            None,
        ));
    };
    let ended = ends_at < Utc::now();

    let enrollment = match exams::get_enrollment(&mut conn, *exam_id, user.id).await? {
        Some(enrollment) => enrollment,
        _ => {
            // user has not started the exam
            let token = authorize(&mut conn, Act::Edit, Some(user.id), Res::Exam(*exam_id)).await?;
            let can_enroll =
                models::library::progressing::user_can_take_exam(&mut conn, *exam_id, user.id)
                    .await?;
            return token.authorized_ok(web::Json(ExamData {
                id: exam.id,
                name: exam.name,
                instructions: exam.instructions,
                starts_at,
                ends_at,
                ended,
                time_minutes: exam.time_minutes,
                enrollment_data: ExamEnrollmentData::NotEnrolled { can_enroll },
                language: exam.language,
            }));
        }
    };

    let page = pages::get_page(&mut conn, exam.page_id).await?;

    let token = authorize(&mut conn, Act::Edit, Some(user.id), Res::Exam(*exam_id)).await?;
    token.authorized_ok(web::Json(ExamData {
        id: exam.id,
        name: exam.name,
        instructions: exam.instructions,
        starts_at,
        ends_at,
        ended,
        time_minutes: exam.time_minutes,
        enrollment_data: ExamEnrollmentData::EnrolledAndStarted {
            page_id: exam.page_id,
            page: Box::new(page),
            enrollment,
        },
        language: exam.language,
    }))
}

#[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
#[cfg_attr(feature = "ts_rs", derive(TS))]
pub struct ShowExerciseAnswers {
    pub show_exercise_answers: bool,
}
/**
POST /api/v0/course-material/exams/:id/update-show-exercise-answers

Used for testing an exam, updates wheter exercise answers are shown.
*/
#[instrument(skip(pool))]
pub async fn update_show_exercise_answers(
    pool: web::Data<PgPool>,
    exam_id: web::Path<Uuid>,
    user: AuthUser,
    payload: web::Json<ShowExerciseAnswers>,
) -> ControllerResult<web::Json<()>> {
    let mut conn = pool.acquire().await?;
    let show_answers = payload.show_exercise_answers;
    exams::update_show_exercise_answers(&mut conn, *exam_id, user.id, show_answers).await?;
    let token = authorize(&mut conn, Act::Teach, Some(user.id), Res::Exam(*exam_id)).await?;
    token.authorized_ok(web::Json(()))
}

/**
POST /api/v0/course-material/exams/:id/reset-exam-progress

Used for testing an exam, resets exercise submissions and restarts the exam time.
*/
#[instrument(skip(pool))]
pub async fn reset_exam_progress(
    pool: web::Data<PgPool>,
    exam_id: web::Path<Uuid>,
    user: AuthUser,
) -> ControllerResult<web::Json<()>> {
    let mut conn = pool.acquire().await?;

    let started_at = Utc::now();
    exams::update_exam_start_time(&mut conn, *exam_id, user.id, started_at).await?;

    models::exercise_slide_submissions::delete_exercise_submissions_with_exam_id_and_user_id(
        &mut conn, *exam_id, user.id,
    )
    .await?;

    let token = authorize(&mut conn, Act::Teach, Some(user.id), Res::Exam(*exam_id)).await?;
    token.authorized_ok(web::Json(()))
}

/**
POST /api/v0/course-material/exams/:id/end-exam-time

Used for marking the students exam as ended in the exam enrollment
*/
#[instrument(skip(pool))]
pub async fn end_exam_time(
    pool: web::Data<PgPool>,
    exam_id: web::Path<Uuid>,
    user: AuthUser,
) -> ControllerResult<web::Json<()>> {
    let mut conn = pool.acquire().await?;

    let ended_at = Utc::now();
    models::exams::update_exam_ended_at(&mut conn, *exam_id, user.id, ended_at).await?;

    let token = authorize(&mut conn, Act::View, Some(user.id), Res::Exam(*exam_id)).await?;
    token.authorized_ok(web::Json(()))
}

/**
Add a route for each controller in this module.

The name starts with an underline in order to appear before other functions in the module documentation.

We add the routes by calling the route method instead of using the route annotations because this method preserves the function signatures for documentation.
*/
pub fn _add_routes(cfg: &mut ServiceConfig) {
    cfg.route("/{id}/enrollment", web::get().to(enrollment))
        .route("/{id}/enroll", web::post().to(enroll))
        .route("/{id}", web::get().to(fetch_exam_for_user))
        .route(
            "/testexam/{id}/fetch-exam-for-testing",
            web::get().to(fetch_exam_for_testing),
        )
        .route(
            "/testexam/{id}/update-show-exercise-answers",
            web::post().to(update_show_exercise_answers),
        )
        .route(
            "/testexam/{id}/reset-exam-progress",
            web::post().to(reset_exam_progress),
        )
        .route("/{id}/end-exam-time", web::post().to(end_exam_time));
}