package models

import (
	"database/sql"
	"time"
)

type User struct {
	ID           int64
	Name         string
	PasswordHash string
	CreatedAt    time.Time
}

type Question struct {
	ID        string // sha256(text)[:8 bytes] hex = 16 chars
	Text      string
	Source    string
	CreatedAt time.Time
}

type Answer struct {
	ID         int64
	QuestionID string
	Text       string
	IsCorrect  bool
	Position   int
}

type Test struct {
	ID          int64
	UserID      int64
	CreatedAt   time.Time
	CompletedAt sql.NullTime
	NQuestions  int
	QuestionIDs []string // unmarshaled from JSON
}

type TestAnswer struct {
	TestID           int64
	QuestionID       string
	SelectedAnswerID sql.NullInt64
	IsCorrect        sql.NullBool
	AnsweredAt       sql.NullTime
}

// Draft holds LLM-extracted questions pending user review before import.
type Draft struct {
	ID        string
	UserID    int64
	Source    string
	Questions []DraftQuestion
	CreatedAt time.Time
}

type DraftQuestion struct {
	Text    string        `json:"text"`
	Answers []DraftAnswer `json:"answers"`
}

type DraftAnswer struct {
	Text      string `json:"text"`
	IsCorrect bool   `json:"is_correct"`
}

type UserQuestionStat struct {
	UserID       int64
	QuestionID   string
	TimesSeen    int
	TimesCorrect int
	LastSeenAt   sql.NullTime
}