package repository

import (
	"context"
	"errors"
	"strings"
	"time"

	dbmodel "github.com/danyel/go-guess/backend/internal/database/entity"
	dbmapper "github.com/danyel/go-guess/backend/internal/database/mapper"
	servicemodel "github.com/danyel/go-guess/backend/internal/service/model"
	"github.com/danyel/go-guess/backend/internal/web/middleware"
	"github.com/jackc/pgx/v5/pgconn"
	"github.com/testcontainers/testcontainers-go/log"
	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

var (
	ErrNotFound            = errors.New("record not found")
	ErrConflict            = errors.New("record conflicts with existing data")
	ErrInterviewNotStarted = errors.New("interview is not started")
)

type IStore interface {
	FindUserByEmail(context.Context, string) (servicemodel.User, error)
	ListUsers(context.Context) ([]servicemodel.User, error)
	CreateUser(context.Context, servicemodel.User) (servicemodel.User, error)
	ListJobs(context.Context) ([]servicemodel.JobPosting, error)
	GetJob(context.Context, uint) (servicemodel.JobPosting, error)
	CreateJob(context.Context, servicemodel.JobPosting) (servicemodel.JobPosting, error)
	UpdateJob(context.Context, uint, string, int) (servicemodel.JobPosting, error)
	ListQuestions(context.Context, string) ([]servicemodel.Question, error)
	GetQuestion(context.Context, uint) (servicemodel.Question, error)
	CreateQuestion(context.Context, servicemodel.Question) (servicemodel.Question, error)
	UpdateQuestion(context.Context, uint, servicemodel.Question) (servicemodel.Question, error)
	SetQuestionDeprecated(context.Context, uint, bool) (servicemodel.Question, error)
	AttachQuestion(context.Context, uint, uint) error
	DetachQuestion(context.Context, uint, uint) error
	ListParticipants(context.Context) ([]servicemodel.Participant, error)
	GetParticipant(context.Context, uint) (servicemodel.Participant, error)
	CreateParticipant(context.Context, servicemodel.Participant) (servicemodel.Participant, error)
	UpdateParticipant(context.Context, servicemodel.Participant) (servicemodel.Participant, error)
	AllTraits(context.Context) ([]servicemodel.Trait, error)
	ListInvitations(context.Context, uint) ([]servicemodel.Invitation, error)
	CreateInvitation(context.Context, servicemodel.Invitation) (servicemodel.Invitation, error)
	GetInterview(context.Context, string) (servicemodel.Interview, error)
	AcceptInvitation(context.Context, string, time.Time) error
	SaveAnswer(context.Context, string, uint, string) error
	CompleteInvitation(context.Context, string, time.Time) error
	GetInvitation(context.Context, uint, uint) (servicemodel.Invitation, error)
	UpdateInvitationOutcome(context.Context, uint, uint, string) (servicemodel.Invitation, error)
	CreateScheduledInterview(context.Context, servicemodel.ScheduledInterview, []uint) (servicemodel.ScheduledInterview, error)
	ListScheduledInterviews(context.Context, uint) ([]servicemodel.ScheduledInterview, error)
	GetScheduledInterview(context.Context, uint) (servicemodel.ScheduledInterview, error)
	GetScheduledInterviewByToken(context.Context, string) (servicemodel.ScheduledInterview, error)
	UpdateScheduledInterviewStatus(context.Context, uint, string) (servicemodel.ScheduledInterview, error)
	UpdateScheduledInterviewDocument(context.Context, uint, string) (servicemodel.ScheduledInterview, error)
	ListInterviewNotes(context.Context, uint) ([]servicemodel.InterviewNote, error)
	CreateInterviewNote(context.Context, servicemodel.InterviewNote) (servicemodel.InterviewNote, error)
	ListInbox(context.Context, uint) ([]servicemodel.ScheduledInterview, error)
	UpdateAttendeeStatus(context.Context, uint, uint, string) (servicemodel.InterviewAttendee, error)
	ListCalendar(context.Context, uint) ([]servicemodel.ScheduledInterview, error)
}

type Store struct {
	d *gorm.DB
}

func New(db *gorm.DB) *Store {
	return &Store{d: db}
}

func (s *Store) db(ctx context.Context) *gorm.DB {
	// Vervang 'yourproject/middleware' door het echte importpad naar je middleware
	if tx, ok := ctx.Value(middleware.TxKey).(*gorm.DB); ok {
		log.Printf("Using tenant-isolated database schema transaction")
		return tx.WithContext(ctx)
	}

	log.Printf("WARNING: Falling back to global public database connection!")
	return s.d.WithContext(ctx)
}

func (s *Store) FindUserByEmail(ctx context.Context, email string) (servicemodel.User, error) {
	var value dbmodel.User
	if err := s.db(ctx).Where("lower(email) = ?", strings.ToLower(email)).First(&value).Error; err != nil {
		return servicemodel.User{}, mapError(err)
	}
	return dbmapper.UserToService(value), nil
}

func (s *Store) ListUsers(ctx context.Context) ([]servicemodel.User, error) {
	var values []dbmodel.User
	if err := s.db(ctx).Order("display_name, email").Find(&values).Error; err != nil {
		return nil, err
	}
	result := make([]servicemodel.User, len(values))
	for i, value := range values {
		result[i] = dbmapper.UserToService(value)
		result[i].PasswordHash = ""
	}
	return result, nil
}

func (s *Store) CreateUser(ctx context.Context, value servicemodel.User) (servicemodel.User, error) {
	entity := dbmodel.User{
		Email: value.Email, PasswordHash: value.PasswordHash,
		DisplayName: value.DisplayName, Role: value.Role,
	}
	if err := s.db(ctx).Create(&entity).Error; err != nil {
		return servicemodel.User{}, mapError(err)
	}
	result := dbmapper.UserToService(entity)
	result.PasswordHash = ""
	return result, nil
}

func (s *Store) ListJobs(ctx context.Context) ([]servicemodel.JobPosting, error) {
	var values []dbmodel.JobPosting
	if err := preloadJob(s.db(ctx)).Order("created_at DESC").Find(&values).Error; err != nil {
		return nil, err
	}
	result := make([]servicemodel.JobPosting, len(values))
	for i, value := range values {
		result[i] = dbmapper.JobToService(value)
	}
	return result, nil
}

func (s *Store) GetJob(ctx context.Context, id uint) (servicemodel.JobPosting, error) {
	var value dbmodel.JobPosting
	if err := preloadJob(s.db(ctx)).First(&value, id).Error; err != nil {
		return servicemodel.JobPosting{}, mapError(err)
	}
	return dbmapper.JobToService(value), nil
}

func (s *Store) CreateJob(ctx context.Context, value servicemodel.JobPosting) (servicemodel.JobPosting, error) {
	entity := dbmodel.JobPosting{
		Title: value.Title, Description: value.Description, Seniority: value.Seniority,
		Position: value.Position, Status: value.Status, DurationMinutes: value.DurationMinutes,
	}
	var err error
	entity.Labels, err = s.resolveTraits(ctx, value.Labels)
	if err != nil {
		return servicemodel.JobPosting{}, err
	}
	entity.RequiredSkills, err = s.resolveTraits(ctx, value.RequiredSkills)
	if err != nil {
		return servicemodel.JobPosting{}, err
	}
	entity.AdditionalSkills, err = s.resolveTraits(ctx, value.AdditionalSkills)
	if err != nil {
		return servicemodel.JobPosting{}, err
	}
	if err := s.db(ctx).Create(&entity).Error; err != nil {
		return servicemodel.JobPosting{}, mapError(err)
	}
	return s.GetJob(ctx, entity.ID)
}

func (s *Store) UpdateJob(ctx context.Context, id uint, status string, durationMinutes int) (servicemodel.JobPosting, error) {
	result := s.db(ctx).Model(&dbmodel.JobPosting{}).Where("id = ?", id).
		Updates(map[string]any{"status": status, "duration_minutes": durationMinutes})
	if result.Error != nil {
		return servicemodel.JobPosting{}, result.Error
	}
	if result.RowsAffected == 0 {
		return servicemodel.JobPosting{}, ErrNotFound
	}
	return s.GetJob(ctx, id)
}

func (s *Store) ListQuestions(ctx context.Context, search string) ([]servicemodel.Question, error) {
	query := s.db(ctx).Preload("Options").Order("deprecated, created_at DESC")
	if search = strings.TrimSpace(search); search != "" {
		query = query.Where("text ILIKE ?", "%"+search+"%")
	}
	var values []dbmodel.Question
	if err := query.Find(&values).Error; err != nil {
		return nil, err
	}
	result := make([]servicemodel.Question, len(values))
	for i, value := range values {
		result[i] = dbmapper.QuestionToService(value)
	}
	return result, nil
}

func (s *Store) GetQuestion(ctx context.Context, id uint) (servicemodel.Question, error) {
	var value dbmodel.Question
	if err := s.db(ctx).Preload("Options").First(&value, id).Error; err != nil {
		return servicemodel.Question{}, mapError(err)
	}
	return dbmapper.QuestionToService(value), nil
}

func (s *Store) CreateQuestion(ctx context.Context, value servicemodel.Question) (servicemodel.Question, error) {
	options := make([]dbmodel.QuestionOption, len(value.Options))
	for i, option := range value.Options {
		options[i] = dbmodel.QuestionOption{Text: option}
	}
	entity := dbmodel.Question{
		Text: value.Text, Type: value.Type, Options: options,
		CodeSnippet: value.CodeSnippet, ReferenceAnswer: value.ReferenceAnswer,
		Deprecated: value.Deprecated,
	}
	if err := s.db(ctx).Create(&entity).Error; err != nil {
		return servicemodel.Question{}, mapError(err)
	}
	return s.GetQuestion(ctx, entity.ID)
}

func (s *Store) UpdateQuestion(ctx context.Context, id uint, value servicemodel.Question) (servicemodel.Question, error) {
	err := s.db(ctx).Transaction(func(tx *gorm.DB) error {
		result := tx.Model(&dbmodel.Question{}).Where("id = ?", id).
			Updates(map[string]any{
				"text": value.Text, "type": value.Type, "code_snippet": value.CodeSnippet,
				"reference_answer": value.ReferenceAnswer,
			})
		if result.Error != nil {
			return result.Error
		}
		if result.RowsAffected == 0 {
			return ErrNotFound
		}
		if err := tx.Where("question_id = ?", id).Delete(&dbmodel.QuestionOption{}).Error; err != nil {
			return err
		}
		if len(value.Options) == 0 {
			return nil
		}
		options := make([]dbmodel.QuestionOption, len(value.Options))
		for i, option := range value.Options {
			options[i] = dbmodel.QuestionOption{QuestionID: id, Text: option}
		}
		return tx.Create(&options).Error
	})
	if err != nil {
		return servicemodel.Question{}, mapError(err)
	}
	return s.GetQuestion(ctx, id)
}

func (s *Store) SetQuestionDeprecated(ctx context.Context, id uint, deprecated bool) (servicemodel.Question, error) {
	result := s.db(ctx).Model(&dbmodel.Question{}).Where("id = ?", id).
		Update("deprecated", deprecated)
	if result.Error != nil {
		return servicemodel.Question{}, result.Error
	}
	if result.RowsAffected == 0 {
		return servicemodel.Question{}, ErrNotFound
	}
	return s.GetQuestion(ctx, id)
}

func (s *Store) AttachQuestion(ctx context.Context, jobID, questionID uint) error {
	var job dbmodel.JobPosting
	if err := s.db(ctx).First(&job, jobID).Error; err != nil {
		return mapError(err)
	}
	var question dbmodel.Question
	if err := s.db(ctx).First(&question, questionID).Error; err != nil {
		return mapError(err)
	}
	var invitations int64
	if err := s.db(ctx).Model(&dbmodel.Invitation{}).Where("job_id = ?", jobID).
		Count(&invitations).Error; err != nil {
		return err
	}
	if invitations > 0 {
		return ErrConflict
	}
	return mapError(s.db(ctx).Model(&job).Association("Questions").Append(&question))
}

func (s *Store) DetachQuestion(ctx context.Context, jobID, questionID uint) error {
	var job dbmodel.JobPosting
	if err := s.db(ctx).First(&job, jobID).Error; err != nil {
		return mapError(err)
	}
	var invitations int64
	if err := s.db(ctx).Model(&dbmodel.Invitation{}).Where("job_id = ?", jobID).
		Count(&invitations).Error; err != nil {
		return err
	}
	if invitations > 0 {
		return ErrConflict
	}
	return s.db(ctx).Model(&job).Association("Questions").
		Delete(&dbmodel.Question{ID: questionID})
}

func (s *Store) ListParticipants(ctx context.Context) ([]servicemodel.Participant, error) {
	var values []dbmodel.Participant
	if err := s.db(ctx).Preload("Traits").Order("last_name, first_name").Find(&values).Error; err != nil {
		return nil, err
	}
	result := make([]servicemodel.Participant, len(values))
	for i, value := range values {
		result[i] = dbmapper.ParticipantToService(value)
	}
	return result, nil
}

func (s *Store) GetParticipant(ctx context.Context, id uint) (servicemodel.Participant, error) {
	var value dbmodel.Participant
	if err := s.db(ctx).Preload("Traits").First(&value, id).Error; err != nil {
		return servicemodel.Participant{}, mapError(err)
	}
	return dbmapper.ParticipantToService(value), nil
}

func (s *Store) CreateParticipant(ctx context.Context, value servicemodel.Participant) (servicemodel.Participant, error) {
	entity := dbmodel.Participant{
		FirstName: value.FirstName, LastName: value.LastName, Birthday: value.Birthday,
		Email: value.Email, ContactInfo: value.ContactInfo, Photo: value.Photo,
		PhotoType: value.PhotoType, CV: value.CV, CVFilename: value.CVFilename,
	}
	var err error
	entity.Traits, err = s.resolveTraits(ctx, value.Traits)
	if err != nil {
		return servicemodel.Participant{}, err
	}
	if err := s.db(ctx).Create(&entity).Error; err != nil {
		return servicemodel.Participant{}, mapError(err)
	}
	return s.GetParticipant(ctx, entity.ID)
}

func (s *Store) UpdateParticipant(ctx context.Context, value servicemodel.Participant) (servicemodel.Participant, error) {
	entity := dbmodel.Participant{
		ID:        value.ID,
		FirstName: value.FirstName, LastName: value.LastName, Birthday: value.Birthday,
		Email: value.Email, ContactInfo: value.ContactInfo, Photo: value.Photo,
		PhotoType: value.PhotoType, CV: value.CV, CVFilename: value.CVFilename,
	}
	db := s.db(ctx)
	if err := db.Transaction(func(tx *gorm.DB) error {
		traits, err := resolveTraits(tx, value.Traits)
		if err != nil {
			return err
		}
		entity.Traits = traits
		result := tx.Model(&dbmodel.Participant{}).Where("id = ?", value.ID).Updates(map[string]any{
			"first_name": value.FirstName, "last_name": value.LastName, "birthday": value.Birthday,
			"email": value.Email, "contact_info": value.ContactInfo, "photo": value.Photo,
			"photo_type": value.PhotoType, "cv": value.CV, "cv_filename": value.CVFilename,
		})
		if result.Error != nil {
			return mapError(result.Error)
		}
		if result.RowsAffected == 0 {
			return ErrNotFound
		}
		return tx.Model(&entity).Association("Traits").Replace(entity.Traits)
	}); err != nil {
		return servicemodel.Participant{}, err
	}
	return s.GetParticipant(ctx, entity.ID)
}

func (s *Store) AllTraits(ctx context.Context) ([]servicemodel.Trait, error) {
	var values []dbmodel.Trait
	if err := s.db(ctx).Order("name").Find(&values).Error; err != nil {
		return nil, err
	}
	result := make([]servicemodel.Trait, len(values))
	for i, value := range values {
		result[i] = servicemodel.Trait{ID: value.ID, Name: value.Name}
	}
	return result, nil
}

func (s *Store) ListInvitations(ctx context.Context, jobID uint) ([]servicemodel.Invitation, error) {
	var values []dbmodel.Invitation
	if err := s.db(ctx).Preload("Participant").Where("job_id = ?", jobID).
		Order("created_at DESC").Find(&values).Error; err != nil {
		return nil, err
	}
	result := make([]servicemodel.Invitation, len(values))
	for i, value := range values {
		result[i] = dbmapper.InvitationToService(value)
	}
	return result, nil
}

func (s *Store) CreateInvitation(ctx context.Context, value servicemodel.Invitation) (servicemodel.Invitation, error) {
	entity := dbmodel.Invitation{
		JobID: value.JobID, ParticipantID: value.ParticipantID,
		Token: value.Token, Status: value.Status, DurationMinutes: value.DurationMinutes,
	}
	if err := s.db(ctx).Create(&entity).Error; err != nil {
		return servicemodel.Invitation{}, mapError(err)
	}
	var created dbmodel.Invitation
	if err := s.db(ctx).Preload("Participant").First(&created, entity.ID).Error; err != nil {
		return servicemodel.Invitation{}, mapError(err)
	}
	return dbmapper.InvitationToService(created), nil
}

func (s *Store) GetInterview(ctx context.Context, token string) (servicemodel.Interview, error) {
	var invitation dbmodel.Invitation
	err := s.db(ctx).Preload("Participant").Preload("Answers").
		Preload("Job.Labels").Preload("Job.RequiredSkills").Preload("Job.AdditionalSkills").
		Preload("Job.Questions.Options").Where("token = ?", token).First(&invitation).Error
	if err != nil {
		return servicemodel.Interview{}, mapError(err)
	}
	answers := make(map[uint]string, len(invitation.Answers))
	for _, answer := range invitation.Answers {
		answers[answer.QuestionID] = answer.Answer
	}
	return servicemodel.Interview{
		Invitation: dbmapper.InvitationToService(invitation),
		Job:        dbmapper.JobToService(invitation.Job),
		Answers:    answers,
	}, nil
}

func (s *Store) AcceptInvitation(ctx context.Context, token string, acceptedAt time.Time) error {
	result := s.db(ctx).Model(&dbmodel.Invitation{}).
		Where("token = ? AND status = ?", token, "pending").
		Updates(map[string]any{"status": "accepted", "accepted_at": acceptedAt})
	if result.Error != nil {
		return result.Error
	}
	if result.RowsAffected == 0 {
		return ErrConflict
	}
	return nil
}

func (s *Store) SaveAnswer(ctx context.Context, token string, questionID uint, answer string) error {
	var invitation dbmodel.Invitation
	if err := s.db(ctx).Where("token = ?", token).First(&invitation).Error; err != nil {
		return mapError(err)
	}
	value := dbmodel.InvitationAnswer{InvitationID: invitation.ID, QuestionID: questionID, Answer: answer}
	return s.db(ctx).Clauses(clause.OnConflict{
		Columns:   []clause.Column{{Name: "invitation_id"}, {Name: "question_id"}},
		DoUpdates: clause.AssignmentColumns([]string{"answer", "updated_at"}),
	}).Create(&value).Error
}

func (s *Store) CompleteInvitation(ctx context.Context, token string, completedAt time.Time) error {
	result := s.db(ctx).Model(&dbmodel.Invitation{}).
		Where("token = ? AND status = ?", token, "accepted").
		Updates(map[string]any{"status": "completed", "completed_at": completedAt})
	if result.Error != nil {
		return result.Error
	}
	if result.RowsAffected == 0 {
		return ErrConflict
	}
	return nil
}

func (s *Store) GetInvitation(ctx context.Context, jobID, invitationID uint) (servicemodel.Invitation, error) {
	var value dbmodel.Invitation
	if err := s.db(ctx).Preload("Participant").
		Where("id = ? AND job_id = ?", invitationID, jobID).First(&value).Error; err != nil {
		return servicemodel.Invitation{}, mapError(err)
	}
	return dbmapper.InvitationToService(value), nil
}

func (s *Store) UpdateInvitationOutcome(
	ctx context.Context, jobID, invitationID uint, outcome string,
) (servicemodel.Invitation, error) {
	result := s.db(ctx).Model(&dbmodel.Invitation{}).
		Where("id = ? AND job_id = ?", invitationID, jobID).Update("outcome", outcome)
	if result.Error != nil {
		return servicemodel.Invitation{}, mapError(result.Error)
	}
	if result.RowsAffected == 0 {
		return servicemodel.Invitation{}, ErrNotFound
	}
	return s.GetInvitation(ctx, jobID, invitationID)
}

func (s *Store) CreateScheduledInterview(
	ctx context.Context, value servicemodel.ScheduledInterview, interviewerIDs []uint,
) (servicemodel.ScheduledInterview, error) {
	entity := dbmodel.ScheduledInterview{
		JobID: value.JobID, InvitationID: value.InvitationID, ParticipantID: value.ParticipantID,
		CreatorID: value.CreatorID, StartsAt: value.StartsAt, Location: value.Location,
		CandidateToken: value.CandidateToken, SharedDocument: value.SharedDocument, Status: value.Status,
	}
	err := s.db(ctx).Transaction(func(tx *gorm.DB) error {
		if err := tx.Create(&entity).Error; err != nil {
			return err
		}
		attendees := make([]dbmodel.InterviewAttendee, 0, len(interviewerIDs))
		for _, userID := range interviewerIDs {
			status := "invited"
			if userID == value.CreatorID {
				status = "accepted"
			}
			attendees = append(attendees, dbmodel.InterviewAttendee{
				InterviewID: entity.ID, UserID: userID, Status: status,
			})
		}
		return tx.Create(&attendees).Error
	})
	if err != nil {
		return servicemodel.ScheduledInterview{}, mapError(err)
	}
	return s.GetScheduledInterview(ctx, entity.ID)
}

func (s *Store) ListScheduledInterviews(ctx context.Context, jobID uint) ([]servicemodel.ScheduledInterview, error) {
	var values []dbmodel.ScheduledInterview
	if err := preloadScheduledInterview(s.db(ctx)).Where("job_id = ?", jobID).
		Order("starts_at").Find(&values).Error; err != nil {
		return nil, err
	}
	return scheduledInterviewsToService(values), nil
}

func (s *Store) GetScheduledInterview(ctx context.Context, id uint) (servicemodel.ScheduledInterview, error) {
	var value dbmodel.ScheduledInterview
	if err := preloadScheduledInterview(s.db(ctx)).First(&value, id).Error; err != nil {
		return servicemodel.ScheduledInterview{}, mapError(err)
	}
	return dbmapper.ScheduledInterviewToService(value), nil
}

func (s *Store) GetScheduledInterviewByToken(ctx context.Context, token string) (servicemodel.ScheduledInterview, error) {
	var value dbmodel.ScheduledInterview
	if err := preloadScheduledInterview(s.db(ctx)).
		Where("candidate_token = ?", token).First(&value).Error; err != nil {
		return servicemodel.ScheduledInterview{}, mapError(err)
	}
	return dbmapper.ScheduledInterviewToService(value), nil
}

func (s *Store) UpdateScheduledInterviewStatus(
	ctx context.Context, id uint, status string,
) (servicemodel.ScheduledInterview, error) {
	result := s.db(ctx).Model(&dbmodel.ScheduledInterview{}).
		Where("id = ?", id).Update("status", status)
	if result.Error != nil {
		return servicemodel.ScheduledInterview{}, result.Error
	}
	if result.RowsAffected == 0 {
		return servicemodel.ScheduledInterview{}, ErrNotFound
	}
	return s.GetScheduledInterview(ctx, id)
}

func (s *Store) UpdateScheduledInterviewDocument(
	ctx context.Context, id uint, document string,
) (servicemodel.ScheduledInterview, error) {
	result := s.db(ctx).Model(&dbmodel.ScheduledInterview{}).
		Where("id = ?", id).Update("shared_document", document)
	if result.Error != nil {
		return servicemodel.ScheduledInterview{}, result.Error
	}
	if result.RowsAffected == 0 {
		return servicemodel.ScheduledInterview{}, ErrNotFound
	}
	return s.GetScheduledInterview(ctx, id)
}

func (s *Store) ListInterviewNotes(ctx context.Context, interviewID uint) ([]servicemodel.InterviewNote, error) {
	var values []dbmodel.InterviewNote
	if err := s.db(ctx).Preload("Author").Where("interview_id = ?", interviewID).
		Order("created_at, id").Find(&values).Error; err != nil {
		return nil, err
	}
	result := make([]servicemodel.InterviewNote, len(values))
	for i, value := range values {
		result[i] = dbmapper.InterviewNoteToService(value)
	}
	return result, nil
}

func (s *Store) CreateInterviewNote(
	ctx context.Context, value servicemodel.InterviewNote,
) (servicemodel.InterviewNote, error) {
	entity := dbmodel.InterviewNote{
		InterviewID: value.InterviewID, AuthorID: value.AuthorID, Body: value.Body,
	}
	if err := s.db(ctx).Transaction(func(tx *gorm.DB) error {
		var interview dbmodel.ScheduledInterview
		if err := tx.Clauses(clause.Locking{Strength: "UPDATE"}).
			Select("id", "status").First(&interview, value.InterviewID).Error; err != nil {
			return err
		}
		if interview.Status != "started" {
			return ErrInterviewNotStarted
		}
		return tx.Create(&entity).Error
	}); err != nil {
		if errors.Is(err, ErrInterviewNotStarted) {
			return servicemodel.InterviewNote{}, err
		}
		return servicemodel.InterviewNote{}, mapError(err)
	}
	if err := s.db(ctx).Preload("Author").First(&entity, entity.ID).Error; err != nil {
		return servicemodel.InterviewNote{}, mapError(err)
	}
	return dbmapper.InterviewNoteToService(entity), nil
}

func (s *Store) ListInbox(ctx context.Context, userID uint) ([]servicemodel.ScheduledInterview, error) {
	var values []dbmodel.ScheduledInterview
	if err := preloadScheduledInterview(s.db(ctx)).
		Joins("JOIN interview_attendees inbox_attendee ON inbox_attendee.interview_id = scheduled_interviews.id").
		Where("inbox_attendee.user_id = ?", userID).
		Order("inbox_attendee.created_at DESC").Find(&values).Error; err != nil {
		return nil, err
	}
	return scheduledInterviewsToService(values), nil
}

func (s *Store) UpdateAttendeeStatus(
	ctx context.Context, interviewID, userID uint, status string,
) (servicemodel.InterviewAttendee, error) {
	result := s.db(ctx).Model(&dbmodel.InterviewAttendee{}).
		Where("interview_id = ? AND user_id = ?", interviewID, userID).Update("status", status)
	if result.Error != nil {
		return servicemodel.InterviewAttendee{}, result.Error
	}
	if result.RowsAffected == 0 {
		return servicemodel.InterviewAttendee{}, ErrNotFound
	}
	var value dbmodel.InterviewAttendee
	if err := s.db(ctx).Preload("User").
		Where("interview_id = ? AND user_id = ?", interviewID, userID).First(&value).Error; err != nil {
		return servicemodel.InterviewAttendee{}, mapError(err)
	}
	attendee := servicemodel.InterviewAttendee{
		ID: value.ID, InterviewID: value.InterviewID, UserID: value.UserID,
		Status: value.Status, User: dbmapper.UserToService(value.User),
		CreatedAt: value.CreatedAt, UpdatedAt: value.UpdatedAt,
	}
	attendee.User.PasswordHash = ""
	return attendee, nil
}

func (s *Store) ListCalendar(ctx context.Context, userID uint) ([]servicemodel.ScheduledInterview, error) {
	var values []dbmodel.ScheduledInterview
	if err := preloadScheduledInterview(s.db(ctx)).
		Joins("JOIN interview_attendees ON interview_attendees.interview_id = scheduled_interviews.id").
		Where("interview_attendees.user_id = ? AND interview_attendees.status <> ?", userID, "declined").
		Order("scheduled_interviews.starts_at").Find(&values).Error; err != nil {
		return nil, err
	}
	return scheduledInterviewsToService(values), nil
}

func (s *Store) resolveTraits(ctx context.Context, values []servicemodel.Trait) ([]dbmodel.Trait, error) {
	return resolveTraits(s.db(ctx), values)
}

func resolveTraits(db *gorm.DB, values []servicemodel.Trait) ([]dbmodel.Trait, error) {
	result := make([]dbmodel.Trait, 0, len(values))
	seen := make(map[string]struct{}, len(values))
	for _, value := range values {
		name := strings.TrimSpace(value.Name)
		normalized := strings.ToLower(name)
		if normalized == "" {
			continue
		}
		if _, ok := seen[normalized]; ok {
			continue
		}
		seen[normalized] = struct{}{}
		var trait dbmodel.Trait
		if err := db.Where(dbmodel.Trait{Normalized: normalized}).
			Attrs(dbmodel.Trait{Name: name}).FirstOrCreate(&trait).Error; err != nil {
			return nil, err
		}
		result = append(result, trait)
	}
	return result, nil
}

func preloadJob(db *gorm.DB) *gorm.DB {
	return db.Preload("Labels").Preload("RequiredSkills").Preload("AdditionalSkills").
		Preload("Questions.Options")
}

func preloadScheduledInterview(db *gorm.DB) *gorm.DB {
	return db.Preload("Job", func(db *gorm.DB) *gorm.DB {
		return db.Select("id", "title")
	}).Preload("Participant", func(db *gorm.DB) *gorm.DB {
		return db.Select("id", "first_name", "last_name")
	}).
		Preload("Creator").Preload("Attendees.User").Preload("Notes.Author")
}

func scheduledInterviewsToService(values []dbmodel.ScheduledInterview) []servicemodel.ScheduledInterview {
	result := make([]servicemodel.ScheduledInterview, len(values))
	for i, value := range values {
		result[i] = dbmapper.ScheduledInterviewToService(value)
	}
	return result
}

func mapError(err error) error {
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return ErrNotFound
	}
	var pgError *pgconn.PgError
	if errors.As(err, &pgError) && pgError.Code == "23505" {
		return ErrConflict
	}
	return err
}