Yimaru-BackEnd/internal/repository/questions.go

package repository

import (
	"context"
	"encoding/json"
	"errors"
	"strings"
	"time"

	dbgen "Yimaru-Backend/gen/db"
	"Yimaru-Backend/internal/domain"

	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgtype"
)

func toPgText(s *string) pgtype.Text {
	if s == nil {
		return pgtype.Text{Valid: false}
	}
	return pgtype.Text{String: *s, Valid: true}
}

func fromPgText(t pgtype.Text) *string {
	if !t.Valid {
		return nil
	}
	return &t.String
}

func fromPgInt4(i pgtype.Int4) *int32 {
	if !i.Valid {
		return nil
	}
	return &i.Int32
}

func fromPgInt8(i pgtype.Int8) *int64 {
	if !i.Valid {
		return nil
	}
	return &i.Int64
}

func toPgInt4(i *int32) pgtype.Int4 {
	if i == nil {
		return pgtype.Int4{Valid: false}
	}
	return pgtype.Int4{Int32: *i, Valid: true}
}

func toPgInt8(i *int64) pgtype.Int8 {
	if i == nil {
		return pgtype.Int8{Valid: false}
	}
	return pgtype.Int8{Int64: *i, Valid: true}
}

func timePtr(t pgtype.Timestamptz) *time.Time {
	if !t.Valid {
		return nil
	}
	return &t.Time
}

func questionToDomain(q dbgen.Question) domain.Question {
	return domain.Question{
		ID:                       q.ID,
		QuestionText:             q.QuestionText,
		QuestionType:             q.QuestionType,
		QuestionTypeDefinitionID: fromPgInt8(q.QuestionTypeDefinitionID),
		DynamicPayload:           parseDynamicPayload(q.DynamicPayload),
		DifficultyLevel:          fromPgText(q.DifficultyLevel),
		Points:                   q.Points,
		Explanation:              fromPgText(q.Explanation),
		Tips:                     fromPgText(q.Tips),
		VoicePrompt:              fromPgText(q.VoicePrompt),
		SampleAnswerVoicePrompt:  fromPgText(q.SampleAnswerVoicePrompt),
		ImageURL:                 fromPgText(q.ImageUrl),
		Status:                   q.Status,
		CreatedAt:                q.CreatedAt.Time,
		UpdatedAt:                timePtr(q.UpdatedAt),
	}
}

func parseDynamicPayload(raw []byte) *domain.DynamicQuestionPayload {
	if len(raw) == 0 {
		return nil
	}
	var payload domain.DynamicQuestionPayload
	if err := json.Unmarshal(raw, &payload); err != nil {
		return nil
	}
	return &payload
}

func encodeDynamicPayload(payload *domain.DynamicQuestionPayload) []byte {
	if payload == nil {
		return nil
	}
	b, err := json.Marshal(payload)
	if err != nil {
		return nil
	}
	return b
}

func (s *Store) setQuestionTypeDefinitionID(ctx context.Context, questionID int64, definitionID *int64) error {
	_, err := s.conn.Exec(ctx, `
		UPDATE questions
		SET question_type_definition_id = $2, updated_at = CURRENT_TIMESTAMP
		WHERE id = $1
	`, questionID, toPgInt8(definitionID))
	return err
}

func questionOptionToDomain(o dbgen.QuestionOption) domain.QuestionOption {
	return domain.QuestionOption{
		ID:          o.ID,
		QuestionID:  o.QuestionID,
		OptionText:  o.OptionText,
		OptionOrder: o.OptionOrder,
		IsCorrect:   o.IsCorrect,
		CreatedAt:   o.CreatedAt.Time,
	}
}

func questionShortAnswerToDomain(a dbgen.QuestionShortAnswer) domain.QuestionShortAnswer {
	return domain.QuestionShortAnswer{
		ID:               a.ID,
		QuestionID:       a.QuestionID,
		AcceptableAnswer: a.AcceptableAnswer,
		MatchType:        a.MatchType,
		CreatedAt:        a.CreatedAt.Time,
	}
}

func questionAudioAnswerToDomain(a dbgen.QuestionAudioAnswer) domain.QuestionAudioAnswer {
	return domain.QuestionAudioAnswer{
		ID:                a.ID,
		QuestionID:        a.QuestionID,
		CorrectAnswerText: a.CorrectAnswerText,
		CreatedAt:         a.CreatedAt.Time,
	}
}

func questionSetToDomain(qs dbgen.QuestionSet) domain.QuestionSet {
	return domain.QuestionSet{
		ID:               qs.ID,
		Title:            qs.Title,
		Description:      fromPgText(qs.Description),
		SetType:          qs.SetType,
		OwnerType:        fromPgText(qs.OwnerType),
		OwnerID:          fromPgInt8(qs.OwnerID),
		BannerImage:      fromPgText(qs.BannerImage),
		Persona:          fromPgText(qs.Persona),
		TimeLimitMinutes: fromPgInt4(qs.TimeLimitMinutes),
		PassingScore:     fromPgInt4(qs.PassingScore),
		ShuffleQuestions: qs.ShuffleQuestions,
		Status:           qs.Status,
		IntroVideoURL:    fromPgText(qs.IntroVideoUrl),
		CreatedAt:        qs.CreatedAt.Time,
		UpdatedAt:        timePtr(qs.UpdatedAt),
	}
}

func questionSetItemToDomain(i dbgen.QuestionSetItem) domain.QuestionSetItem {
	return domain.QuestionSetItem{
		ID:           i.ID,
		SetID:        i.SetID,
		QuestionID:   i.QuestionID,
		DisplayOrder: i.DisplayOrder,
		CreatedAt:    i.CreatedAt.Time,
	}
}

func questionTypeDefinitionToDomain(
	id int64,
	key string,
	displayName string,
	description pgtype.Text,
	stimulusKinds []string,
	responseKinds []string,
	stimulusSchema []byte,
	responseSchema []byte,
	isSystem bool,
	status string,
	createdAt time.Time,
	updatedAt pgtype.Timestamptz,
) domain.QuestionTypeDefinition {
	var stimulusSchemaDef []domain.DynamicElementDefinition
	var responseSchemaDef []domain.DynamicElementDefinition
	if len(stimulusSchema) > 0 {
		_ = json.Unmarshal(stimulusSchema, &stimulusSchemaDef)
	}
	if len(responseSchema) > 0 {
		_ = json.Unmarshal(responseSchema, &responseSchemaDef)
	}

	return domain.QuestionTypeDefinition{
		ID:                     id,
		Key:                    key,
		DisplayName:            displayName,
		Description:            fromPgText(description),
		StimulusComponentKinds: stimulusKinds,
		ResponseComponentKinds: responseKinds,
		StimulusSchema:         stimulusSchemaDef,
		ResponseSchema:         responseSchemaDef,
		IsSystem:               isSystem,
		Status:                 status,
		CreatedAt:              createdAt,
		UpdatedAt:              timePtr(updatedAt),
	}
}

func normalizeDefinitionStatus(status *string) string {
	if status == nil || strings.TrimSpace(*status) == "" {
		return "ACTIVE"
	}
	return strings.ToUpper(strings.TrimSpace(*status))
}

func normalizeDefinitionKinds(values []string) []string {
	out := make([]string, 0, len(values))
	for _, v := range values {
		trimmed := strings.TrimSpace(v)
		if trimmed == "" {
			continue
		}
		out = append(out, trimmed)
	}
	return out
}

func normalizeDefinitionKey(key string) string {
	key = strings.TrimSpace(strings.ToLower(key))
	key = strings.ReplaceAll(key, " ", "_")
	return key
}

func kindsFromStimulusSchema(schema []domain.DynamicElementDefinition) []string {
	seen := make(map[string]struct{})
	out := make([]string, 0, len(schema))
	for _, el := range schema {
		kind := strings.TrimSpace(el.Kind)
		if kind == "" {
			continue
		}
		if _, exists := seen[kind]; exists {
			continue
		}
		seen[kind] = struct{}{}
		out = append(out, kind)
	}
	return out
}

func kindsFromResponseSchema(schema []domain.DynamicElementDefinition) []string {
	seen := make(map[string]struct{})
	out := make([]string, 0, len(schema))
	for _, el := range schema {
		kind := strings.TrimSpace(el.Kind)
		if kind == "" {
			continue
		}
		if _, exists := seen[kind]; exists {
			continue
		}
		seen[kind] = struct{}{}
		out = append(out, kind)
	}
	return out
}

func mustJSON(v interface{}) []byte {
	b, err := json.Marshal(v)
	if err != nil {
		return []byte("[]")
	}
	return b
}

func (s *Store) CreateQuestionTypeDefinition(ctx context.Context, input domain.CreateQuestionTypeDefinitionInput) (domain.QuestionTypeDefinition, error) {
	normalizedKey := normalizeDefinitionKey(input.Key)
	stimulusKinds := normalizeDefinitionKinds(input.StimulusComponentKinds)
	responseKinds := normalizeDefinitionKinds(input.ResponseComponentKinds)
	stimulusSchema := input.StimulusSchema
	responseSchema := input.ResponseSchema

	if len(stimulusKinds) == 0 && len(stimulusSchema) > 0 {
		stimulusKinds = kindsFromStimulusSchema(stimulusSchema)
	}
	if len(responseKinds) == 0 && len(responseSchema) > 0 {
		responseKinds = kindsFromResponseSchema(responseSchema)
	}

	if err := domain.ValidateDynamicQuestionTypeDefinition(stimulusKinds, responseKinds); err != nil {
		return domain.QuestionTypeDefinition{}, err
	}
	if err := domain.ValidateDefinitionSchemas(stimulusSchema, responseSchema); err != nil {
		return domain.QuestionTypeDefinition{}, err
	}
	if err := domain.ValidatePersistableQuestionTypeDefinition(normalizedKey, responseKinds); err != nil {
		return domain.QuestionTypeDefinition{}, err
	}

	row := s.conn.QueryRow(ctx, `
		INSERT INTO question_type_definitions
			(key, display_name, description, stimulus_component_kinds, response_component_kinds, stimulus_schema, response_schema, is_system, status)
		VALUES ($1, $2, $3, $4, $5, $6::jsonb, $7::jsonb, $8, $9)
		RETURNING id, key, display_name, description, stimulus_component_kinds, response_component_kinds, stimulus_schema, response_schema, is_system, status, created_at, updated_at
	`,
		normalizedKey,
		strings.TrimSpace(input.DisplayName),
		toPgText(input.Description),
		stimulusKinds,
		responseKinds,
		mustJSON(stimulusSchema),
		mustJSON(responseSchema),
		input.IsSystem,
		normalizeDefinitionStatus(input.Status),
	)

	var (
		id          int64
		key         string
		displayName string
		description pgtype.Text
		stimulus    []string
		response    []string
		stimulusSch []byte
		responseSch []byte
		isSystem    bool
		status      string
		createdAt   time.Time
		updatedAt   pgtype.Timestamptz
	)
	if err := row.Scan(&id, &key, &displayName, &description, &stimulus, &response, &stimulusSch, &responseSch, &isSystem, &status, &createdAt, &updatedAt); err != nil {
		return domain.QuestionTypeDefinition{}, err
	}

	return questionTypeDefinitionToDomain(id, key, displayName, description, stimulus, response, stimulusSch, responseSch, isSystem, status, createdAt, updatedAt), nil
}

func (s *Store) GetQuestionTypeDefinitionByID(ctx context.Context, id int64) (domain.QuestionTypeDefinition, error) {
	row := s.conn.QueryRow(ctx, `
		SELECT id, key, display_name, description, stimulus_component_kinds, response_component_kinds, stimulus_schema, response_schema, is_system, status, created_at, updated_at
		FROM question_type_definitions
		WHERE id = $1
	`, id)

	var (
		key         string
		displayName string
		description pgtype.Text
		stimulus    []string
		response    []string
		stimulusSch []byte
		responseSch []byte
		isSystem    bool
		status      string
		createdAt   time.Time
		updatedAt   pgtype.Timestamptz
	)
	if err := row.Scan(&id, &key, &displayName, &description, &stimulus, &response, &stimulusSch, &responseSch, &isSystem, &status, &createdAt, &updatedAt); err != nil {
		return domain.QuestionTypeDefinition{}, err
	}
	return questionTypeDefinitionToDomain(id, key, displayName, description, stimulus, response, stimulusSch, responseSch, isSystem, status, createdAt, updatedAt), nil
}

func (s *Store) ListQuestionTypeDefinitions(ctx context.Context, status *string, includeSystem bool) ([]domain.QuestionTypeDefinition, error) {
	rows, err := s.conn.Query(ctx, `
		SELECT id, key, display_name, description, stimulus_component_kinds, response_component_kinds, stimulus_schema, response_schema, is_system, status, created_at, updated_at
		FROM question_type_definitions
		WHERE ($1::VARCHAR IS NULL OR status = $1)
		  AND ($2::BOOLEAN = TRUE OR is_system = FALSE)
		ORDER BY is_system DESC, display_name ASC
	`, status, includeSystem)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var out []domain.QuestionTypeDefinition
	for rows.Next() {
		var (
			id          int64
			key         string
			displayName string
			description pgtype.Text
			stimulus    []string
			response    []string
			stimulusSch []byte
			responseSch []byte
			isSystem    bool
			defStatus   string
			createdAt   time.Time
			updatedAt   pgtype.Timestamptz
		)
		if err := rows.Scan(&id, &key, &displayName, &description, &stimulus, &response, &stimulusSch, &responseSch, &isSystem, &defStatus, &createdAt, &updatedAt); err != nil {
			return nil, err
		}
		out = append(out, questionTypeDefinitionToDomain(id, key, displayName, description, stimulus, response, stimulusSch, responseSch, isSystem, defStatus, createdAt, updatedAt))
	}

	return out, rows.Err()
}

func (s *Store) UpdateQuestionTypeDefinition(ctx context.Context, id int64, input domain.UpdateQuestionTypeDefinitionInput) error {
	existing, err := s.GetQuestionTypeDefinitionByID(ctx, id)
	if err != nil {
		return err
	}

	displayName := existing.DisplayName
	if input.DisplayName != nil && strings.TrimSpace(*input.DisplayName) != "" {
		displayName = strings.TrimSpace(*input.DisplayName)
	}

	description := existing.Description
	if input.Description != nil {
		description = input.Description
	}

	stimulusKinds := existing.StimulusComponentKinds
	if input.StimulusComponentKinds != nil {
		stimulusKinds = normalizeDefinitionKinds(input.StimulusComponentKinds)
	}

	responseKinds := existing.ResponseComponentKinds
	if input.ResponseComponentKinds != nil {
		responseKinds = normalizeDefinitionKinds(input.ResponseComponentKinds)
	}
	stimulusSchema := existing.StimulusSchema
	if input.StimulusSchema != nil {
		stimulusSchema = input.StimulusSchema
	}
	responseSchema := existing.ResponseSchema
	if input.ResponseSchema != nil {
		responseSchema = input.ResponseSchema
	}

	if len(stimulusKinds) == 0 && len(stimulusSchema) > 0 {
		stimulusKinds = kindsFromStimulusSchema(stimulusSchema)
	}
	if len(responseKinds) == 0 && len(responseSchema) > 0 {
		responseKinds = kindsFromResponseSchema(responseSchema)
	}

	if err := domain.ValidateDynamicQuestionTypeDefinition(stimulusKinds, responseKinds); err != nil {
		return err
	}
	if err := domain.ValidateDefinitionSchemas(stimulusSchema, responseSchema); err != nil {
		return err
	}
	if err := domain.ValidatePersistableQuestionTypeDefinition(existing.Key, responseKinds); err != nil {
		return err
	}

	status := existing.Status
	if input.Status != nil {
		status = normalizeDefinitionStatus(input.Status)
	}

	_, err = s.conn.Exec(ctx, `
		UPDATE question_type_definitions
		SET display_name = $2,
		    description = $3,
		    stimulus_component_kinds = $4,
		    response_component_kinds = $5,
		    stimulus_schema = $6::jsonb,
		    response_schema = $7::jsonb,
		    status = $8,
		    updated_at = NOW()
		WHERE id = $1
	`, id, displayName, toPgText(description), stimulusKinds, responseKinds, mustJSON(stimulusSchema), mustJSON(responseSchema), status)
	return err
}

func (s *Store) DeleteQuestionTypeDefinition(ctx context.Context, id int64) error {
	var isSystem bool
	err := s.conn.QueryRow(ctx, `SELECT is_system FROM question_type_definitions WHERE id = $1`, id).Scan(&isSystem)
	if err != nil {
		return err
	}
	if isSystem {
		return errors.New("system question type definitions cannot be deleted")
	}

	cmd, err := s.conn.Exec(ctx, `DELETE FROM question_type_definitions WHERE id = $1`, id)
	if err != nil {
		return err
	}
	if cmd.RowsAffected() == 0 {
		return pgx.ErrNoRows
	}
	return nil
}

func (s *Store) CreateQuestion(ctx context.Context, input domain.CreateQuestionInput) (domain.Question, error) {
	q, tx, err := s.BeginTx(ctx)
	if err != nil {
		return domain.Question{}, err
	}
	defer tx.Rollback(ctx)

	var points interface{}
	if input.Points != nil {
		points = *input.Points
	}
	var status interface{}
	if input.Status != nil {
		status = *input.Status
	}

	question, err := q.CreateQuestion(ctx, dbgen.CreateQuestionParams{
		QuestionText:            input.QuestionText,
		QuestionType:            input.QuestionType,
		DifficultyLevel:         toPgText(input.DifficultyLevel),
		Column4:                 points,
		Explanation:             toPgText(input.Explanation),
		Tips:                    toPgText(input.Tips),
		VoicePrompt:             toPgText(input.VoicePrompt),
		SampleAnswerVoicePrompt: toPgText(input.SampleAnswerVoicePrompt),
		ImageUrl:                toPgText(input.ImageURL),
		Column10:                status,
		Column11:                encodeDynamicPayload(input.DynamicPayload),
	})
	if err != nil {
		return domain.Question{}, err
	}

	for _, opt := range input.Options {
		var order interface{}
		if opt.OptionOrder != nil {
			order = *opt.OptionOrder
		}
		_, err = q.CreateQuestionOption(ctx, dbgen.CreateQuestionOptionParams{
			QuestionID: question.ID,
			OptionText: opt.OptionText,
			Column3:    order,
			Column4:    opt.IsCorrect,
		})
		if err != nil {
			return domain.Question{}, err
		}
	}

	for _, sa := range input.ShortAnswers {
		var matchType interface{}
		if sa.MatchType != nil {
			matchType = *sa.MatchType
		}
		_, err = q.CreateQuestionShortAnswer(ctx, dbgen.CreateQuestionShortAnswerParams{
			QuestionID:       question.ID,
			AcceptableAnswer: sa.AcceptableAnswer,
			Column3:          matchType,
		})
		if err != nil {
			return domain.Question{}, err
		}
	}

	if input.AudioCorrectAnswerText != nil && *input.AudioCorrectAnswerText != "" {
		_, err = q.CreateQuestionAudioAnswer(ctx, dbgen.CreateQuestionAudioAnswerParams{
			QuestionID:        question.ID,
			CorrectAnswerText: *input.AudioCorrectAnswerText,
		})
		if err != nil {
			return domain.Question{}, err
		}
	}

	if err = s.setQuestionTypeDefinitionID(ctx, question.ID, input.QuestionTypeDefinitionID); err != nil {
		return domain.Question{}, err
	}

	if err = tx.Commit(ctx); err != nil {
		return domain.Question{}, err
	}

	created := questionToDomain(question)
	created.QuestionTypeDefinitionID = input.QuestionTypeDefinitionID
	return created, nil
}

func (s *Store) GetQuestionByID(ctx context.Context, id int64) (domain.Question, error) {
	q, err := s.queries.GetQuestionByID(ctx, id)
	if err != nil {
		return domain.Question{}, err
	}
	return questionToDomain(q), nil
}

func (s *Store) GetQuestionWithDetails(ctx context.Context, id int64) (domain.QuestionWithDetails, error) {
	q, err := s.queries.GetQuestionByID(ctx, id)
	if err != nil {
		return domain.QuestionWithDetails{}, err
	}

	opts, err := s.queries.GetOptionsByQuestionID(ctx, id)
	if err != nil {
		return domain.QuestionWithDetails{}, err
	}

	shortAnswers, err := s.queries.GetShortAnswersByQuestionID(ctx, id)
	if err != nil {
		return domain.QuestionWithDetails{}, err
	}

	options := make([]domain.QuestionOption, len(opts))
	for i, o := range opts {
		options[i] = questionOptionToDomain(o)
	}

	answers := make([]domain.QuestionShortAnswer, len(shortAnswers))
	for i, a := range shortAnswers {
		answers[i] = questionShortAnswerToDomain(a)
	}

	var audioAnswer *domain.QuestionAudioAnswer
	aa, err := s.queries.GetAudioAnswerByQuestionID(ctx, id)
	if err == nil {
		mapped := questionAudioAnswerToDomain(aa)
		audioAnswer = &mapped
	}

	return domain.QuestionWithDetails{
		Question:     questionToDomain(q),
		Options:      options,
		ShortAnswers: answers,
		AudioAnswer:  audioAnswer,
	}, nil
}

func (s *Store) ListQuestions(ctx context.Context, questionType, difficulty, status *string, limit, offset int32) ([]domain.Question, int64, error) {
	var qType, diff, stat string
	if questionType != nil {
		qType = *questionType
	}
	if difficulty != nil {
		diff = *difficulty
	}
	if status != nil {
		stat = *status
	}

	rows, err := s.queries.ListQuestions(ctx, dbgen.ListQuestionsParams{
		Column1: qType,
		Column2: diff,
		Column3: stat,
		Limit:   pgtype.Int4{Int32: limit, Valid: true},
		Offset:  pgtype.Int4{Int32: offset, Valid: true},
	})
	if err != nil {
		return nil, 0, err
	}

	var totalCount int64
	questions := make([]domain.Question, len(rows))
	for i, r := range rows {
		if i == 0 {
			totalCount = r.TotalCount
		}
		questions[i] = domain.Question{
			ID:                       r.ID,
			QuestionText:             r.QuestionText,
			QuestionType:             r.QuestionType,
			QuestionTypeDefinitionID: fromPgInt8(r.QuestionTypeDefinitionID),
			DynamicPayload:           parseDynamicPayload(r.DynamicPayload),
			DifficultyLevel:          fromPgText(r.DifficultyLevel),
			Points:                   r.Points,
			Explanation:              fromPgText(r.Explanation),
			Tips:                     fromPgText(r.Tips),
			VoicePrompt:              fromPgText(r.VoicePrompt),
			SampleAnswerVoicePrompt:  fromPgText(r.SampleAnswerVoicePrompt),
			ImageURL:                 fromPgText(r.ImageUrl),
			Status:                   r.Status,
			CreatedAt:                r.CreatedAt.Time,
			UpdatedAt:                timePtr(r.UpdatedAt),
		}
	}

	return questions, totalCount, nil
}

func (s *Store) SearchQuestions(ctx context.Context, query string, limit, offset int32) ([]domain.Question, int64, error) {
	rows, err := s.queries.SearchQuestions(ctx, dbgen.SearchQuestionsParams{
		Column1: pgtype.Text{String: query, Valid: true},
		Limit:   pgtype.Int4{Int32: limit, Valid: true},
		Offset:  pgtype.Int4{Int32: offset, Valid: true},
	})
	if err != nil {
		return nil, 0, err
	}

	var totalCount int64
	questions := make([]domain.Question, len(rows))
	for i, r := range rows {
		if i == 0 {
			totalCount = r.TotalCount
		}
		questions[i] = domain.Question{
			ID:                       r.ID,
			QuestionText:             r.QuestionText,
			QuestionType:             r.QuestionType,
			QuestionTypeDefinitionID: fromPgInt8(r.QuestionTypeDefinitionID),
			DynamicPayload:           parseDynamicPayload(r.DynamicPayload),
			DifficultyLevel:          fromPgText(r.DifficultyLevel),
			Points:                   r.Points,
			Explanation:              fromPgText(r.Explanation),
			Tips:                     fromPgText(r.Tips),
			VoicePrompt:              fromPgText(r.VoicePrompt),
			SampleAnswerVoicePrompt:  fromPgText(r.SampleAnswerVoicePrompt),
			ImageURL:                 fromPgText(r.ImageUrl),
			Status:                   r.Status,
			CreatedAt:                r.CreatedAt.Time,
			UpdatedAt:                timePtr(r.UpdatedAt),
		}
	}

	return questions, totalCount, nil
}

func (s *Store) UpdateQuestion(ctx context.Context, id int64, input domain.CreateQuestionInput) error {
	var points int32
	if input.Points != nil {
		points = *input.Points
	}
	var status string
	if input.Status != nil {
		status = *input.Status
	}

	err := s.queries.UpdateQuestion(ctx, dbgen.UpdateQuestionParams{
		ID:                      id,
		QuestionText:            input.QuestionText,
		QuestionType:            input.QuestionType,
		DifficultyLevel:         toPgText(input.DifficultyLevel),
		Points:                  points,
		Explanation:             toPgText(input.Explanation),
		Tips:                    toPgText(input.Tips),
		VoicePrompt:             toPgText(input.VoicePrompt),
		SampleAnswerVoicePrompt: toPgText(input.SampleAnswerVoicePrompt),
		ImageUrl:                toPgText(input.ImageURL),
		Status:                  status,
		Column11:                encodeDynamicPayload(input.DynamicPayload),
	})
	if err != nil {
		return err
	}

	if input.AudioCorrectAnswerText != nil {
		_ = s.queries.DeleteAudioAnswerByQuestionID(ctx, id)
		if *input.AudioCorrectAnswerText != "" {
			_, err = s.queries.CreateQuestionAudioAnswer(ctx, dbgen.CreateQuestionAudioAnswerParams{
				QuestionID:        id,
				CorrectAnswerText: *input.AudioCorrectAnswerText,
			})
			if err != nil {
				return err
			}
		}
	}

	if input.QuestionTypeDefinitionID != nil {
		if err := s.setQuestionTypeDefinitionID(ctx, id, input.QuestionTypeDefinitionID); err != nil {
			return err
		}
	}

	return nil
}

func (s *Store) ArchiveQuestion(ctx context.Context, id int64) error {
	return s.queries.ArchiveQuestion(ctx, id)
}

func (s *Store) DeleteQuestion(ctx context.Context, id int64) error {
	return s.queries.DeleteQuestion(ctx, id)
}

func (s *Store) CreateQuestionOption(ctx context.Context, questionID int64, optionText string, optionOrder *int32, isCorrect bool) (domain.QuestionOption, error) {
	var order interface{}
	if optionOrder != nil {
		order = *optionOrder
	}

	opt, err := s.queries.CreateQuestionOption(ctx, dbgen.CreateQuestionOptionParams{
		QuestionID: questionID,
		OptionText: optionText,
		Column3:    order,
		Column4:    isCorrect,
	})
	if err != nil {
		return domain.QuestionOption{}, err
	}
	return questionOptionToDomain(opt), nil
}

func (s *Store) GetOptionsByQuestionID(ctx context.Context, questionID int64) ([]domain.QuestionOption, error) {
	opts, err := s.queries.GetOptionsByQuestionID(ctx, questionID)
	if err != nil {
		return nil, err
	}

	result := make([]domain.QuestionOption, len(opts))
	for i, o := range opts {
		result[i] = questionOptionToDomain(o)
	}
	return result, nil
}

func (s *Store) UpdateQuestionOption(ctx context.Context, id int64, optionText *string, optionOrder *int32, isCorrect *bool) error {
	var text string
	if optionText != nil {
		text = *optionText
	}
	var order int32
	if optionOrder != nil {
		order = *optionOrder
	}
	var correct bool
	if isCorrect != nil {
		correct = *isCorrect
	}

	return s.queries.UpdateQuestionOption(ctx, dbgen.UpdateQuestionOptionParams{
		ID:          id,
		OptionText:  text,
		OptionOrder: order,
		IsCorrect:   correct,
	})
}

func (s *Store) DeleteQuestionOption(ctx context.Context, id int64) error {
	return s.queries.DeleteQuestionOption(ctx, id)
}

func (s *Store) DeleteOptionsByQuestionID(ctx context.Context, questionID int64) error {
	return s.queries.DeleteOptionsByQuestionID(ctx, questionID)
}

func (s *Store) CreateQuestionShortAnswer(ctx context.Context, questionID int64, acceptableAnswer string, matchType *string) (domain.QuestionShortAnswer, error) {
	var mt interface{}
	if matchType != nil {
		mt = *matchType
	}

	sa, err := s.queries.CreateQuestionShortAnswer(ctx, dbgen.CreateQuestionShortAnswerParams{
		QuestionID:       questionID,
		AcceptableAnswer: acceptableAnswer,
		Column3:          mt,
	})
	if err != nil {
		return domain.QuestionShortAnswer{}, err
	}
	return questionShortAnswerToDomain(sa), nil
}

func (s *Store) GetShortAnswersByQuestionID(ctx context.Context, questionID int64) ([]domain.QuestionShortAnswer, error) {
	answers, err := s.queries.GetShortAnswersByQuestionID(ctx, questionID)
	if err != nil {
		return nil, err
	}

	result := make([]domain.QuestionShortAnswer, len(answers))
	for i, a := range answers {
		result[i] = questionShortAnswerToDomain(a)
	}
	return result, nil
}

func (s *Store) UpdateQuestionShortAnswer(ctx context.Context, id int64, acceptableAnswer, matchType *string) error {
	var answer, mt string
	if acceptableAnswer != nil {
		answer = *acceptableAnswer
	}
	if matchType != nil {
		mt = *matchType
	}

	return s.queries.UpdateQuestionShortAnswer(ctx, dbgen.UpdateQuestionShortAnswerParams{
		ID:               id,
		AcceptableAnswer: answer,
		MatchType:        mt,
	})
}

func (s *Store) DeleteQuestionShortAnswer(ctx context.Context, id int64) error {
	return s.queries.DeleteQuestionShortAnswer(ctx, id)
}

func (s *Store) DeleteShortAnswersByQuestionID(ctx context.Context, questionID int64) error {
	return s.queries.DeleteShortAnswersByQuestionID(ctx, questionID)
}

func (s *Store) CreateQuestionSet(ctx context.Context, input domain.CreateQuestionSetInput) (domain.QuestionSet, error) {
	var shuffleQuestions interface{}
	if input.ShuffleQuestions != nil {
		shuffleQuestions = *input.ShuffleQuestions
	}
	var status interface{}
	if input.Status != nil {
		status = *input.Status
	}

	qs, err := s.queries.CreateQuestionSet(ctx, dbgen.CreateQuestionSetParams{
		Title:            input.Title,
		Description:      toPgText(input.Description),
		SetType:          input.SetType,
		OwnerType:        toPgText(input.OwnerType),
		OwnerID:          toPgInt8(input.OwnerID),
		BannerImage:      toPgText(input.BannerImage),
		Persona:          toPgText(input.Persona),
		TimeLimitMinutes: toPgInt4(input.TimeLimitMinutes),
		PassingScore:     toPgInt4(input.PassingScore),
		Column10:         shuffleQuestions,
		Column11:         status,
		IntroVideoUrl:    toPgText(input.IntroVideoURL),
	})
	if err != nil {
		return domain.QuestionSet{}, err
	}
	return questionSetToDomain(qs), nil
}

func (s *Store) GetQuestionSetByID(ctx context.Context, id int64) (domain.QuestionSet, error) {
	qs, err := s.queries.GetQuestionSetByID(ctx, id)
	if err != nil {
		return domain.QuestionSet{}, err
	}
	return questionSetToDomain(qs), nil
}

func (s *Store) GetQuestionSetsByOwner(ctx context.Context, ownerType string, ownerID int64) ([]domain.QuestionSet, error) {
	sets, err := s.queries.GetQuestionSetsByOwner(ctx, dbgen.GetQuestionSetsByOwnerParams{
		OwnerType: pgtype.Text{String: ownerType, Valid: true},
		OwnerID:   pgtype.Int8{Int64: ownerID, Valid: true},
	})
	if err != nil {
		return nil, err
	}

	result := make([]domain.QuestionSet, len(sets))
	for i, qs := range sets {
		result[i] = questionSetToDomain(qs)
	}
	return result, nil
}

func (s *Store) GetQuestionSetsByType(ctx context.Context, setType string, limit, offset int32) ([]domain.QuestionSet, int64, error) {
	rows, err := s.queries.GetQuestionSetsByType(ctx, dbgen.GetQuestionSetsByTypeParams{
		SetType: setType,
		Limit:   pgtype.Int4{Int32: limit, Valid: true},
		Offset:  pgtype.Int4{Int32: offset, Valid: true},
	})
	if err != nil {
		return nil, 0, err
	}

	var totalCount int64
	result := make([]domain.QuestionSet, len(rows))
	for i, r := range rows {
		if i == 0 {
			totalCount = r.TotalCount
		}
		result[i] = domain.QuestionSet{
			ID:               r.ID,
			Title:            r.Title,
			Description:      fromPgText(r.Description),
			SetType:          r.SetType,
			OwnerType:        fromPgText(r.OwnerType),
			OwnerID:          fromPgInt8(r.OwnerID),
			BannerImage:      fromPgText(r.BannerImage),
			Persona:          fromPgText(r.Persona),
			TimeLimitMinutes: fromPgInt4(r.TimeLimitMinutes),
			PassingScore:     fromPgInt4(r.PassingScore),
			ShuffleQuestions: r.ShuffleQuestions,
			Status:           r.Status,
			IntroVideoURL:    fromPgText(r.IntroVideoUrl),
			CreatedAt:        r.CreatedAt.Time,
			UpdatedAt:        timePtr(r.UpdatedAt),
		}
	}

	// COUNT(*) OVER() only appears when at least one row is returned.
	// For out-of-range offsets, fetch total count explicitly so pagination metadata stays correct.
	if len(rows) == 0 {
		err = s.conn.QueryRow(
			ctx,
			`SELECT COUNT(*) FROM question_sets WHERE set_type = $1 AND status != 'ARCHIVED'`,
			setType,
		).Scan(&totalCount)
		if err != nil {
			return nil, 0, err
		}
	}
	return result, totalCount, nil
}

func (s *Store) GetPublishedQuestionSetsByOwner(ctx context.Context, ownerType string, ownerID int64) ([]domain.QuestionSet, error) {
	sets, err := s.queries.GetPublishedQuestionSetsByOwner(ctx, dbgen.GetPublishedQuestionSetsByOwnerParams{
		OwnerType: pgtype.Text{String: ownerType, Valid: true},
		OwnerID:   pgtype.Int8{Int64: ownerID, Valid: true},
	})
	if err != nil {
		return nil, err
	}

	result := make([]domain.QuestionSet, len(sets))
	for i, qs := range sets {
		result[i] = questionSetToDomain(qs)
	}
	return result, nil
}

func (s *Store) GetInitialAssessmentSet(ctx context.Context) (domain.QuestionSet, error) {
	qs, err := s.queries.GetInitialAssessmentSet(ctx)
	if err != nil {
		return domain.QuestionSet{}, err
	}
	return questionSetToDomain(qs), nil
}

func (s *Store) GetFirstIncompletePreviousPractice(ctx context.Context, userID int64, questionSetID int64) (*domain.PracticeAccessBlock, error) {
	row, err := s.queries.GetFirstIncompletePreviousPractice(ctx, dbgen.GetFirstIncompletePreviousPracticeParams{
		UserID:        userID,
		QuestionSetID: questionSetID,
	})
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return nil, nil
		}
		return nil, err
	}
	return &domain.PracticeAccessBlock{
		QuestionSetID: row.ID,
		Title:         row.Title,
		DisplayOrder:  row.DisplayOrder,
	}, nil
}

func (s *Store) MarkPracticeCompleted(ctx context.Context, userID int64, questionSetID int64) error {
	_, err := s.queries.MarkPracticeCompleted(ctx, dbgen.MarkPracticeCompletedParams{
		UserID:        userID,
		QuestionSetID: questionSetID,
	})
	return err
}

func (s *Store) UpdateQuestionSet(ctx context.Context, id int64, input domain.CreateQuestionSetInput) error {
	var shuffleQuestions bool
	if input.ShuffleQuestions != nil {
		shuffleQuestions = *input.ShuffleQuestions
	}
	var status string
	if input.Status != nil {
		status = *input.Status
	}

	return s.queries.UpdateQuestionSet(ctx, dbgen.UpdateQuestionSetParams{
		ID:               id,
		Title:            input.Title,
		Description:      toPgText(input.Description),
		BannerImage:      toPgText(input.BannerImage),
		Persona:          toPgText(input.Persona),
		TimeLimitMinutes: toPgInt4(input.TimeLimitMinutes),
		PassingScore:     toPgInt4(input.PassingScore),
		ShuffleQuestions: shuffleQuestions,
		Status:           status,
		IntroVideoUrl:    toPgText(input.IntroVideoURL),
	})
}

func (s *Store) ArchiveQuestionSet(ctx context.Context, id int64) error {
	return s.queries.ArchiveQuestionSet(ctx, id)
}

func (s *Store) DeleteQuestionSet(ctx context.Context, id int64) error {
	return s.queries.DeleteQuestionSet(ctx, id)
}

func (s *Store) AddQuestionToSet(ctx context.Context, setID, questionID int64, displayOrder *int32) (domain.QuestionSetItem, error) {
	var order interface{}
	if displayOrder != nil {
		order = *displayOrder
	}

	item, err := s.queries.AddQuestionToSet(ctx, dbgen.AddQuestionToSetParams{
		SetID:      setID,
		QuestionID: questionID,
		Column3:    order,
	})
	if err != nil {
		return domain.QuestionSetItem{}, err
	}
	return questionSetItemToDomain(item), nil
}

func (s *Store) GetQuestionSetItems(ctx context.Context, setID int64) ([]domain.QuestionSetItemWithQuestion, error) {
	rows, err := s.queries.GetQuestionSetItems(ctx, setID)
	if err != nil {
		return nil, err
	}

	result := make([]domain.QuestionSetItemWithQuestion, len(rows))
	for i, r := range rows {
		result[i] = domain.QuestionSetItemWithQuestion{
			QuestionSetItem: domain.QuestionSetItem{
				ID:           r.ID,
				SetID:        r.SetID,
				QuestionID:   r.QuestionID,
				DisplayOrder: r.DisplayOrder,
			},
			QuestionText:            r.QuestionText,
			QuestionType:            r.QuestionType,
			DynamicPayload:          parseDynamicPayload(r.DynamicPayload),
			DifficultyLevel:         fromPgText(r.DifficultyLevel),
			Points:                  r.Points,
			Explanation:             fromPgText(r.Explanation),
			Tips:                    fromPgText(r.Tips),
			VoicePrompt:             fromPgText(r.VoicePrompt),
			SampleAnswerVoicePrompt: fromPgText(r.SampleAnswerVoicePrompt),
			ImageURL:                fromPgText(r.ImageUrl),
			AudioCorrectAnswerText:  fromPgText(r.AudioCorrectAnswerText),
			QuestionStatus:          r.QuestionStatus,
		}
	}
	return result, nil
}

func (s *Store) GetQuestionSetItemsPaginated(ctx context.Context, setID int64, questionType *string, limit, offset int32) ([]domain.QuestionSetItemWithQuestion, int64, error) {
	qType := ""
	if questionType != nil {
		qType = *questionType
	}
	rows, err := s.queries.GetQuestionSetItemsPaginated(ctx, dbgen.GetQuestionSetItemsPaginatedParams{
		SetID:   setID,
		Column2: qType,
		Offset:  pgtype.Int4{Int32: offset, Valid: true},
		Limit:   pgtype.Int4{Int32: limit, Valid: true},
	})
	if err != nil {
		return nil, 0, err
	}

	var totalCount int64
	result := make([]domain.QuestionSetItemWithQuestion, len(rows))
	for i, r := range rows {
		if i == 0 {
			totalCount = r.TotalCount
		}
		result[i] = domain.QuestionSetItemWithQuestion{
			QuestionSetItem: domain.QuestionSetItem{
				ID:           r.ID,
				SetID:        r.SetID,
				QuestionID:   r.QuestionID,
				DisplayOrder: r.DisplayOrder,
			},
			QuestionText:            r.QuestionText,
			QuestionType:            r.QuestionType,
			DynamicPayload:          parseDynamicPayload(r.DynamicPayload),
			DifficultyLevel:         fromPgText(r.DifficultyLevel),
			Points:                  r.Points,
			Explanation:             fromPgText(r.Explanation),
			Tips:                    fromPgText(r.Tips),
			VoicePrompt:             fromPgText(r.VoicePrompt),
			SampleAnswerVoicePrompt: fromPgText(r.SampleAnswerVoicePrompt),
			ImageURL:                fromPgText(r.ImageUrl),
			AudioCorrectAnswerText:  fromPgText(r.AudioCorrectAnswerText),
			QuestionStatus:          r.QuestionStatus,
		}
	}
	return result, totalCount, nil
}

func (s *Store) GetPublishedQuestionsInSet(ctx context.Context, setID int64) ([]domain.QuestionSetItemWithQuestion, error) {
	rows, err := s.queries.GetPublishedQuestionsInSet(ctx, setID)
	if err != nil {
		return nil, err
	}

	result := make([]domain.QuestionSetItemWithQuestion, len(rows))
	for i, r := range rows {
		result[i] = domain.QuestionSetItemWithQuestion{
			QuestionSetItem: domain.QuestionSetItem{
				ID:           r.ID,
				SetID:        r.SetID,
				QuestionID:   r.QuestionID,
				DisplayOrder: r.DisplayOrder,
			},
			QuestionText:            r.QuestionText,
			QuestionType:            r.QuestionType,
			DynamicPayload:          parseDynamicPayload(r.DynamicPayload),
			DifficultyLevel:         fromPgText(r.DifficultyLevel),
			Points:                  r.Points,
			Explanation:             fromPgText(r.Explanation),
			Tips:                    fromPgText(r.Tips),
			VoicePrompt:             fromPgText(r.VoicePrompt),
			SampleAnswerVoicePrompt: fromPgText(r.SampleAnswerVoicePrompt),
			ImageURL:                fromPgText(r.ImageUrl),
			AudioCorrectAnswerText:  fromPgText(r.AudioCorrectAnswerText),
			QuestionStatus:          "PUBLISHED",
		}
	}
	return result, nil
}

func (s *Store) RemoveQuestionFromSet(ctx context.Context, setID, questionID int64) error {
	return s.queries.RemoveQuestionFromSet(ctx, dbgen.RemoveQuestionFromSetParams{
		SetID:      setID,
		QuestionID: questionID,
	})
}

func (s *Store) UpdateQuestionOrder(ctx context.Context, setID, questionID int64, displayOrder int32) error {
	return s.queries.UpdateQuestionOrder(ctx, dbgen.UpdateQuestionOrderParams{
		SetID:        setID,
		QuestionID:   questionID,
		DisplayOrder: displayOrder,
	})
}

func (s *Store) CountQuestionsInSet(ctx context.Context, setID int64) (int64, error) {
	return s.queries.CountQuestionsInSet(ctx, setID)
}

func (s *Store) GetQuestionSetsContainingQuestion(ctx context.Context, questionID int64) ([]domain.QuestionSet, error) {
	sets, err := s.queries.GetQuestionSetsContainingQuestion(ctx, questionID)
	if err != nil {
		return nil, err
	}

	result := make([]domain.QuestionSet, len(sets))
	for i, qs := range sets {
		result[i] = questionSetToDomain(qs)
	}
	return result, nil
}

// User Persona methods for question sets

func (s *Store) AddUserPersonaToQuestionSet(ctx context.Context, questionSetID, userID int64, displayOrder int32) error {
	_, err := s.queries.AddUserPersonaToQuestionSet(ctx, dbgen.AddUserPersonaToQuestionSetParams{
		QuestionSetID: questionSetID,
		UserID:        userID,
		Column3:       displayOrder,
	})
	return err
}

func (s *Store) RemoveUserPersonaFromQuestionSet(ctx context.Context, questionSetID, userID int64) error {
	return s.queries.RemoveUserPersonaFromQuestionSet(ctx, dbgen.RemoveUserPersonaFromQuestionSetParams{
		QuestionSetID: questionSetID,
		UserID:        userID,
	})
}

func (s *Store) GetUserPersonasByQuestionSetID(ctx context.Context, questionSetID int64) ([]domain.UserPersona, error) {
	rows, err := s.queries.GetUserPersonasByQuestionSetID(ctx, questionSetID)
	if err != nil {
		return nil, err
	}

	result := make([]domain.UserPersona, len(rows))
	for i, r := range rows {
		result[i] = domain.UserPersona{
			ID:                r.ID,
			FirstName:         fromPgText(r.FirstName),
			LastName:          fromPgText(r.LastName),
			NickName:          fromPgText(r.NickName),
			ProfilePictureURL: fromPgText(r.ProfilePictureUrl),
			Role:              r.Role,
			DisplayOrder:      r.DisplayOrder.Int32,
		}
	}
	return result, nil
}

func (s *Store) ReorderQuestionSets(ctx context.Context, ids []int64, positions []int32) error {
	return s.queries.ReorderQuestionSets(ctx, dbgen.ReorderQuestionSetsParams{
		Ids:       ids,
		Positions: positions,
	})
}