Files
Benjamin Boenisch 5a31f52310 Initial commit: breakpilot-lehrer - Lehrer KI Platform
Services: Admin-Lehrer, Backend-Lehrer, Studio v2, Website,
Klausur-Service, School-Service, Voice-Service, Geo-Service,
BreakPilot Drive, Agent-Core

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-11 23:47:26 +01:00

647 lines
21 KiB
Go

package services
import (
"context"
"github.com/breakpilot/school-service/internal/models"
"github.com/jackc/pgx/v5/pgxpool"
)
// GradeService handles grade-related operations
type GradeService struct {
db *pgxpool.Pool
}
// NewGradeService creates a new GradeService
func NewGradeService(db *pgxpool.Pool) *GradeService {
return &GradeService{db: db}
}
// GetGradeOverview returns grade overview for a class
func (s *GradeService) GetGradeOverview(ctx context.Context, classID string, semester int) ([]models.GradeOverview, error) {
rows, err := s.db.Query(ctx, `
SELECT go.id, go.student_id, go.subject_id, go.school_year_id, go.semester,
go.written_grade_avg, go.written_grade_count, go.oral_grade, go.oral_notes,
go.final_grade, go.final_grade_locked, go.written_weight, go.oral_weight,
go.created_at, go.updated_at,
CONCAT(st.first_name, ' ', st.last_name) as student_name,
sub.name as subject_name
FROM grade_overview go
JOIN students st ON go.student_id = st.id
JOIN subjects sub ON go.subject_id = sub.id
WHERE st.class_id = $1 AND go.semester = $2
ORDER BY st.last_name, st.first_name, sub.name
`, classID, semester)
if err != nil {
return nil, err
}
defer rows.Close()
var grades []models.GradeOverview
for rows.Next() {
var g models.GradeOverview
if err := rows.Scan(&g.ID, &g.StudentID, &g.SubjectID, &g.SchoolYearID, &g.Semester, &g.WrittenGradeAvg, &g.WrittenGradeCount, &g.OralGrade, &g.OralNotes, &g.FinalGrade, &g.FinalGradeLocked, &g.WrittenWeight, &g.OralWeight, &g.CreatedAt, &g.UpdatedAt, &g.StudentName, &g.SubjectName); err != nil {
return nil, err
}
grades = append(grades, g)
}
return grades, nil
}
// GetStudentGrades returns all grades for a student
func (s *GradeService) GetStudentGrades(ctx context.Context, studentID string) ([]models.GradeOverview, error) {
rows, err := s.db.Query(ctx, `
SELECT go.id, go.student_id, go.subject_id, go.school_year_id, go.semester,
go.written_grade_avg, go.written_grade_count, go.oral_grade, go.oral_notes,
go.final_grade, go.final_grade_locked, go.written_weight, go.oral_weight,
go.created_at, go.updated_at,
CONCAT(st.first_name, ' ', st.last_name) as student_name,
sub.name as subject_name
FROM grade_overview go
JOIN students st ON go.student_id = st.id
JOIN subjects sub ON go.subject_id = sub.id
WHERE go.student_id = $1
ORDER BY go.school_year_id DESC, go.semester DESC, sub.name
`, studentID)
if err != nil {
return nil, err
}
defer rows.Close()
var grades []models.GradeOverview
for rows.Next() {
var g models.GradeOverview
if err := rows.Scan(&g.ID, &g.StudentID, &g.SubjectID, &g.SchoolYearID, &g.Semester, &g.WrittenGradeAvg, &g.WrittenGradeCount, &g.OralGrade, &g.OralNotes, &g.FinalGrade, &g.FinalGradeLocked, &g.WrittenWeight, &g.OralWeight, &g.CreatedAt, &g.UpdatedAt, &g.StudentName, &g.SubjectName); err != nil {
return nil, err
}
grades = append(grades, g)
}
return grades, nil
}
// UpdateOralGrade updates the oral grade for a student in a subject
func (s *GradeService) UpdateOralGrade(ctx context.Context, studentID, subjectID string, req *models.UpdateOralGradeRequest) (*models.GradeOverview, error) {
// First, get or create the grade overview record
var grade models.GradeOverview
// Try to get the current school year and semester
var schoolYearID string
err := s.db.QueryRow(ctx, `
SELECT sy.id FROM school_years sy
JOIN classes c ON c.school_year_id = sy.id
JOIN students st ON st.class_id = c.id
WHERE st.id = $1 AND sy.is_current = true
LIMIT 1
`, studentID).Scan(&schoolYearID)
if err != nil {
// No current school year found, cannot update
return nil, err
}
// Current semester (simplified - could be calculated from date)
semester := 1
err = s.db.QueryRow(ctx, `
INSERT INTO grade_overview (student_id, subject_id, school_year_id, semester, oral_grade, oral_notes)
VALUES ($1, $2, $3, $4, $5, $6)
ON CONFLICT (student_id, subject_id, school_year_id, semester) DO UPDATE SET
oral_grade = EXCLUDED.oral_grade,
oral_notes = EXCLUDED.oral_notes,
updated_at = NOW()
RETURNING id, student_id, subject_id, school_year_id, semester, written_grade_avg, written_grade_count, oral_grade, oral_notes, final_grade, final_grade_locked, written_weight, oral_weight, created_at, updated_at
`, studentID, subjectID, schoolYearID, semester, req.OralGrade, req.OralNotes).Scan(
&grade.ID, &grade.StudentID, &grade.SubjectID, &grade.SchoolYearID, &grade.Semester, &grade.WrittenGradeAvg, &grade.WrittenGradeCount, &grade.OralGrade, &grade.OralNotes, &grade.FinalGrade, &grade.FinalGradeLocked, &grade.WrittenWeight, &grade.OralWeight, &grade.CreatedAt, &grade.UpdatedAt,
)
return &grade, err
}
// CalculateFinalGrades calculates final grades for all students in a class
func (s *GradeService) CalculateFinalGrades(ctx context.Context, classID string, semester int) error {
// Update written grade averages from approved exam results
_, err := s.db.Exec(ctx, `
WITH avg_grades AS (
SELECT er.student_id, e.subject_id, AVG(er.grade) as avg_grade, COUNT(*) as grade_count
FROM exam_results er
JOIN exams e ON er.exam_id = e.id
JOIN students st ON er.student_id = st.id
WHERE st.class_id = $1 AND er.approved_by_teacher = true AND er.grade IS NOT NULL
GROUP BY er.student_id, e.subject_id
)
UPDATE grade_overview go SET
written_grade_avg = ag.avg_grade,
written_grade_count = ag.grade_count,
updated_at = NOW()
FROM avg_grades ag
WHERE go.student_id = ag.student_id AND go.subject_id = ag.subject_id AND go.semester = $2
`, classID, semester)
if err != nil {
return err
}
// Calculate final grades based on weights
_, err = s.db.Exec(ctx, `
UPDATE grade_overview SET
final_grade = CASE
WHEN oral_grade IS NULL THEN written_grade_avg
WHEN written_grade_avg IS NULL THEN oral_grade
ELSE ROUND((written_grade_avg * written_weight + oral_grade * oral_weight) / (written_weight + oral_weight), 1)
END,
updated_at = NOW()
WHERE student_id IN (SELECT id FROM students WHERE class_id = $1)
AND semester = $2
AND final_grade_locked = false
`, classID, semester)
return err
}
// TransferApprovedGrades transfers approved exam results to grade overview
func (s *GradeService) TransferApprovedGrades(ctx context.Context, teacherID string) error {
// Get current school year
var schoolYearID string
err := s.db.QueryRow(ctx, `
SELECT id FROM school_years WHERE teacher_id = $1 AND is_current = true LIMIT 1
`, teacherID).Scan(&schoolYearID)
if err != nil {
return err
}
// Current semester
semester := 1
// Ensure grade_overview records exist for all students with approved results
_, err = s.db.Exec(ctx, `
INSERT INTO grade_overview (student_id, subject_id, school_year_id, semester)
SELECT DISTINCT er.student_id, e.subject_id, $1, $2
FROM exam_results er
JOIN exams e ON er.exam_id = e.id
WHERE er.approved_by_teacher = true AND e.subject_id IS NOT NULL
ON CONFLICT (student_id, subject_id, school_year_id, semester) DO NOTHING
`, schoolYearID, semester)
return err
}
// LockFinalGrade locks a final grade (prevents further changes)
func (s *GradeService) LockFinalGrade(ctx context.Context, studentID, subjectID string, semester int) error {
_, err := s.db.Exec(ctx, `
UPDATE grade_overview SET final_grade_locked = true, updated_at = NOW()
WHERE student_id = $1 AND subject_id = $2 AND semester = $3
`, studentID, subjectID, semester)
return err
}
// UpdateGradeWeights updates the written/oral weights for grade calculation
func (s *GradeService) UpdateGradeWeights(ctx context.Context, studentID, subjectID string, writtenWeight, oralWeight int) error {
_, err := s.db.Exec(ctx, `
UPDATE grade_overview SET written_weight = $3, oral_weight = $4, updated_at = NOW()
WHERE student_id = $1 AND subject_id = $2
`, studentID, subjectID, writtenWeight, oralWeight)
return err
}
// =============================================
// STATISTICS METHODS
// =============================================
// ClassStatistics holds statistics for a class
type ClassStatistics struct {
ClassID string `json:"class_id"`
ClassName string `json:"class_name"`
StudentCount int `json:"student_count"`
ClassAverage float64 `json:"class_average"`
GradeDistribution map[string]int `json:"grade_distribution"`
BestGrade float64 `json:"best_grade"`
WorstGrade float64 `json:"worst_grade"`
PassRate float64 `json:"pass_rate"`
StudentsAtRisk int `json:"students_at_risk"`
SubjectAverages map[string]float64 `json:"subject_averages"`
}
// SubjectStatistics holds statistics for a subject within a class
type SubjectStatistics struct {
ClassID string `json:"class_id"`
SubjectID string `json:"subject_id"`
SubjectName string `json:"subject_name"`
StudentCount int `json:"student_count"`
Average float64 `json:"average"`
Median float64 `json:"median"`
GradeDistribution map[string]int `json:"grade_distribution"`
BestGrade float64 `json:"best_grade"`
WorstGrade float64 `json:"worst_grade"`
PassRate float64 `json:"pass_rate"`
ExamAverages []ExamAverage `json:"exam_averages"`
}
// ExamAverage holds average for a single exam
type ExamAverage struct {
ExamID string `json:"exam_id"`
Title string `json:"title"`
Average float64 `json:"average"`
ExamDate string `json:"exam_date"`
}
// StudentStatistics holds statistics for a single student
type StudentStatistics struct {
StudentID string `json:"student_id"`
StudentName string `json:"student_name"`
OverallAverage float64 `json:"overall_average"`
SubjectGrades map[string]float64 `json:"subject_grades"`
Trend string `json:"trend"` // "improving", "stable", "declining"
AbsenceDays int `json:"absence_days"`
ExamsCompleted int `json:"exams_completed"`
StrongestSubject string `json:"strongest_subject"`
WeakestSubject string `json:"weakest_subject"`
}
// Notenspiegel represents grade distribution
type Notenspiegel struct {
ClassID string `json:"class_id"`
SubjectID string `json:"subject_id,omitempty"`
ExamID string `json:"exam_id,omitempty"`
Title string `json:"title"`
Distribution map[string]int `json:"distribution"`
Total int `json:"total"`
Average float64 `json:"average"`
PassRate float64 `json:"pass_rate"`
}
// GetClassStatistics returns statistics for a class
func (s *GradeService) GetClassStatistics(ctx context.Context, classID string, semester int) (*ClassStatistics, error) {
stats := &ClassStatistics{
ClassID: classID,
GradeDistribution: make(map[string]int),
SubjectAverages: make(map[string]float64),
}
// Initialize grade distribution
for i := 1; i <= 6; i++ {
stats.GradeDistribution[string('0'+rune(i))] = 0
}
// Get class info and student count
err := s.db.QueryRow(ctx, `
SELECT c.name, COUNT(s.id)
FROM classes c
LEFT JOIN students s ON s.class_id = c.id
WHERE c.id = $1
GROUP BY c.name
`, classID).Scan(&stats.ClassName, &stats.StudentCount)
if err != nil {
return nil, err
}
// Build semester condition
semesterCond := ""
if semester > 0 {
semesterCond = " AND go.semester = " + string('0'+rune(semester))
}
// Get overall statistics from grade_overview
var avgGrade, bestGrade, worstGrade float64
var totalPassed, totalStudents int
err = s.db.QueryRow(ctx, `
SELECT
COALESCE(AVG(go.final_grade), 0),
COALESCE(MIN(go.final_grade), 0),
COALESCE(MAX(go.final_grade), 0),
COUNT(CASE WHEN go.final_grade <= 4.0 THEN 1 END),
COUNT(go.id)
FROM grade_overview go
JOIN students s ON s.id = go.student_id
WHERE s.class_id = $1 AND go.final_grade IS NOT NULL`+semesterCond+`
`, classID).Scan(&avgGrade, &bestGrade, &worstGrade, &totalPassed, &totalStudents)
if err == nil {
stats.ClassAverage = avgGrade
stats.BestGrade = bestGrade
stats.WorstGrade = worstGrade
if totalStudents > 0 {
stats.PassRate = float64(totalPassed) / float64(totalStudents) * 100
}
}
// Get grade distribution
rows, err := s.db.Query(ctx, `
SELECT FLOOR(go.final_grade) as grade_bucket, COUNT(*) as count
FROM grade_overview go
JOIN students s ON s.id = go.student_id
WHERE s.class_id = $1 AND go.final_grade IS NOT NULL`+semesterCond+`
GROUP BY FLOOR(go.final_grade)
`, classID)
if err == nil {
defer rows.Close()
for rows.Next() {
var bucket int
var count int
if err := rows.Scan(&bucket, &count); err == nil && bucket >= 1 && bucket <= 6 {
stats.GradeDistribution[string('0'+rune(bucket))] = count
}
}
}
// Count students at risk
s.db.QueryRow(ctx, `
SELECT COUNT(DISTINCT s.id)
FROM students s
JOIN grade_overview go ON go.student_id = s.id
WHERE s.class_id = $1 AND go.final_grade >= 4.5
`, classID).Scan(&stats.StudentsAtRisk)
// Get subject averages
subjectRows, err := s.db.Query(ctx, `
SELECT sub.name, AVG(go.final_grade)
FROM grade_overview go
JOIN subjects sub ON sub.id = go.subject_id
JOIN students s ON s.id = go.student_id
WHERE s.class_id = $1 AND go.final_grade IS NOT NULL`+semesterCond+`
GROUP BY sub.name
`, classID)
if err == nil {
defer subjectRows.Close()
for subjectRows.Next() {
var name string
var avg float64
if err := subjectRows.Scan(&name, &avg); err == nil {
stats.SubjectAverages[name] = avg
}
}
}
return stats, nil
}
// GetSubjectStatistics returns statistics for a specific subject in a class
func (s *GradeService) GetSubjectStatistics(ctx context.Context, classID, subjectID string, semester int) (*SubjectStatistics, error) {
stats := &SubjectStatistics{
ClassID: classID,
SubjectID: subjectID,
GradeDistribution: make(map[string]int),
ExamAverages: []ExamAverage{},
}
// Initialize grade distribution
for i := 1; i <= 6; i++ {
stats.GradeDistribution[string('0'+rune(i))] = 0
}
// Get subject name and basic stats
semesterCond := ""
if semester > 0 {
semesterCond = " AND go.semester = " + string('0'+rune(semester))
}
err := s.db.QueryRow(ctx, `
SELECT
sub.name,
COUNT(DISTINCT s.id),
COALESCE(AVG(go.final_grade), 0),
COALESCE(MIN(go.final_grade), 0),
COALESCE(MAX(go.final_grade), 0),
COUNT(CASE WHEN go.final_grade <= 4.0 THEN 1 END),
COUNT(go.id)
FROM grade_overview go
JOIN subjects sub ON sub.id = go.subject_id
JOIN students s ON s.id = go.student_id
WHERE s.class_id = $1 AND go.subject_id = $2 AND go.final_grade IS NOT NULL`+semesterCond+`
GROUP BY sub.name
`, classID, subjectID).Scan(
&stats.SubjectName, &stats.StudentCount, &stats.Average,
&stats.BestGrade, &stats.WorstGrade,
new(int), new(int), // We'll calculate pass rate separately
)
if err != nil {
return nil, err
}
// Get grade distribution
rows, err := s.db.Query(ctx, `
SELECT FLOOR(go.final_grade), COUNT(*)
FROM grade_overview go
JOIN students s ON s.id = go.student_id
WHERE s.class_id = $1 AND go.subject_id = $2 AND go.final_grade IS NOT NULL`+semesterCond+`
GROUP BY FLOOR(go.final_grade)
`, classID, subjectID)
if err == nil {
defer rows.Close()
var passed, total int
for rows.Next() {
var bucket, count int
if err := rows.Scan(&bucket, &count); err == nil && bucket >= 1 && bucket <= 6 {
stats.GradeDistribution[string('0'+rune(bucket))] = count
total += count
if bucket <= 4 {
passed += count
}
}
}
if total > 0 {
stats.PassRate = float64(passed) / float64(total) * 100
}
}
// Get exam averages
examRows, err := s.db.Query(ctx, `
SELECT e.id, e.title, AVG(er.grade), COALESCE(e.exam_date::text, '')
FROM exams e
JOIN exam_results er ON er.exam_id = e.id
JOIN students s ON er.student_id = s.id
WHERE s.class_id = $1 AND e.subject_id = $2 AND er.grade IS NOT NULL
GROUP BY e.id, e.title, e.exam_date
ORDER BY e.exam_date DESC NULLS LAST
`, classID, subjectID)
if err == nil {
defer examRows.Close()
for examRows.Next() {
var ea ExamAverage
if err := examRows.Scan(&ea.ExamID, &ea.Title, &ea.Average, &ea.ExamDate); err == nil {
stats.ExamAverages = append(stats.ExamAverages, ea)
}
}
}
return stats, nil
}
// GetStudentStatistics returns statistics for a specific student
func (s *GradeService) GetStudentStatistics(ctx context.Context, studentID string) (*StudentStatistics, error) {
stats := &StudentStatistics{
StudentID: studentID,
SubjectGrades: make(map[string]float64),
}
// Get student name
err := s.db.QueryRow(ctx, `
SELECT CONCAT(first_name, ' ', last_name) FROM students WHERE id = $1
`, studentID).Scan(&stats.StudentName)
if err != nil {
return nil, err
}
// Get subject grades and calculate overall average
var totalGrade, numSubjects float64
var bestGrade float64 = 6
var worstGrade float64 = 1
var bestSubject, worstSubject string
rows, err := s.db.Query(ctx, `
SELECT sub.name, go.final_grade
FROM grade_overview go
JOIN subjects sub ON sub.id = go.subject_id
WHERE go.student_id = $1 AND go.final_grade IS NOT NULL
ORDER BY sub.name
`, studentID)
if err != nil {
return nil, err
}
defer rows.Close()
for rows.Next() {
var name string
var grade float64
if err := rows.Scan(&name, &grade); err == nil {
stats.SubjectGrades[name] = grade
totalGrade += grade
numSubjects++
if grade < bestGrade {
bestGrade = grade
bestSubject = name
}
if grade > worstGrade {
worstGrade = grade
worstSubject = name
}
}
}
if numSubjects > 0 {
stats.OverallAverage = totalGrade / numSubjects
stats.StrongestSubject = bestSubject
stats.WeakestSubject = worstSubject
}
// Count exams completed
s.db.QueryRow(ctx, `
SELECT COUNT(*) FROM exam_results WHERE student_id = $1 AND grade IS NOT NULL
`, studentID).Scan(&stats.ExamsCompleted)
// Count absence days
s.db.QueryRow(ctx, `
SELECT COALESCE(SUM(periods), 0) FROM attendance
WHERE student_id = $1 AND status IN ('absent_excused', 'absent_unexcused')
`, studentID).Scan(&stats.AbsenceDays)
// Determine trend (simplified - compare first and last exam grades)
stats.Trend = "stable"
var firstGrade, lastGrade float64
s.db.QueryRow(ctx, `
SELECT grade FROM exam_results
WHERE student_id = $1 AND grade IS NOT NULL
ORDER BY created_at ASC LIMIT 1
`, studentID).Scan(&firstGrade)
s.db.QueryRow(ctx, `
SELECT grade FROM exam_results
WHERE student_id = $1 AND grade IS NOT NULL
ORDER BY created_at DESC LIMIT 1
`, studentID).Scan(&lastGrade)
if lastGrade < firstGrade-0.5 {
stats.Trend = "improving"
} else if lastGrade > firstGrade+0.5 {
stats.Trend = "declining"
}
return stats, nil
}
// GetNotenspiegel returns grade distribution (Notenspiegel)
func (s *GradeService) GetNotenspiegel(ctx context.Context, classID, subjectID, examID string, semester int) (*Notenspiegel, error) {
ns := &Notenspiegel{
ClassID: classID,
SubjectID: subjectID,
ExamID: examID,
Distribution: make(map[string]int),
}
// Initialize distribution
for i := 1; i <= 6; i++ {
ns.Distribution[string('0'+rune(i))] = 0
}
var query string
var args []interface{}
if examID != "" {
// Notenspiegel for specific exam
query = `
SELECT e.title, FLOOR(er.grade), COUNT(*), AVG(er.grade)
FROM exam_results er
JOIN exams e ON e.id = er.exam_id
WHERE er.exam_id = $1 AND er.grade IS NOT NULL
GROUP BY e.title, FLOOR(er.grade)
`
args = []interface{}{examID}
} else if subjectID != "" {
// Notenspiegel for subject in class
semesterCond := ""
if semester > 0 {
semesterCond = " AND go.semester = " + string('0'+rune(semester))
}
query = `
SELECT sub.name, FLOOR(go.final_grade), COUNT(*), AVG(go.final_grade)
FROM grade_overview go
JOIN subjects sub ON sub.id = go.subject_id
JOIN students s ON s.id = go.student_id
WHERE s.class_id = $1 AND go.subject_id = $2 AND go.final_grade IS NOT NULL` + semesterCond + `
GROUP BY sub.name, FLOOR(go.final_grade)
`
args = []interface{}{classID, subjectID}
} else {
// Notenspiegel for entire class
semesterCond := ""
if semester > 0 {
semesterCond = " AND go.semester = " + string('0'+rune(semester))
}
query = `
SELECT c.name, FLOOR(go.final_grade), COUNT(*), AVG(go.final_grade)
FROM grade_overview go
JOIN students s ON s.id = go.student_id
JOIN classes c ON c.id = s.class_id
WHERE s.class_id = $1 AND go.final_grade IS NOT NULL` + semesterCond + `
GROUP BY c.name, FLOOR(go.final_grade)
`
args = []interface{}{classID}
}
rows, err := s.db.Query(ctx, query, args...)
if err != nil {
return nil, err
}
defer rows.Close()
var passed int
for rows.Next() {
var title string
var bucket, count int
var avg float64
if err := rows.Scan(&title, &bucket, &count, &avg); err == nil {
ns.Title = title
if bucket >= 1 && bucket <= 6 {
ns.Distribution[string('0'+rune(bucket))] = count
ns.Total += count
if bucket <= 4 {
passed += count
}
}
ns.Average = avg
}
}
if ns.Total > 0 {
ns.PassRate = float64(passed) / float64(ns.Total) * 100
}
return ns, nil
}