package database

import (
	"database/sql"
	"log"
	"time"

	_ "github.com/mattn/go-sqlite3"
)

const (
	ExpiryDuration = time.Hour * 24
)

type User struct {
	ID          string    `json:"sub"`
	Mail        string    `json:"email"`
	Username    string    `json:"preferred_username"`
	DisplayName string    `json:"name"`
	CreatedAt   time.Time `json:"created_at"`
}

type UserSession struct {
	ID       string    `json:"id"`
	UserID   string    `json:"user_id"`
	ExpireAt time.Time `json:"expire_at"`
}

func GetUser(dbConn *sql.DB, id string) (*User, error) {
	row := dbConn.QueryRow(`SELECT id, mail, username, display_name, created_at FROM users WHERE id = ?;`, id)

	var user User
	err := row.Scan(&user.ID, &user.Mail, &user.Username, &user.DisplayName, &user.CreatedAt)
	if err != nil {
		log.Println(err)
		return nil, err
	}

	return &user, nil
}

func FindOrSaveUser(dbConn *sql.DB, user *User) (*User, error) {
	_, err := dbConn.Exec(`INSERT OR REPLACE INTO users (id, mail, username, display_name) VALUES (?, ?, ?, ?);`, user.ID, user.Mail, user.Username, user.DisplayName)
	if err != nil {
		return nil, err
	}

	return user, nil
}

func MakeUserSessionFor(dbConn *sql.DB, user *User) (*UserSession, error) {
	expireAt := time.Now().Add(time.Hour * 12)

	_, err := dbConn.Exec(`INSERT OR REPLACE INTO user_sessions (id, user_id, expire_at) VALUES (?, ?, ?);`, user.ID, user.ID, time.Now().Add(ExpiryDuration))

	if err != nil {
		log.Println(err)
		return nil, err
	}

	return &UserSession{
		ID:       user.ID,
		UserID:   user.ID,
		ExpireAt: expireAt,
	}, nil
}

func GetSession(dbConn *sql.DB, sessionId string) (*UserSession, error) {
	row := dbConn.QueryRow(`SELECT id, user_id, expire_at FROM user_sessions WHERE id = ?;`, sessionId)

	var id, userId string
	var expireAt time.Time
	err := row.Scan(&id, &userId, &expireAt)
	if err != nil {
		log.Println(err)
		return nil, err
	}

	return &UserSession{
		ID:       id,
		UserID:   userId,
		ExpireAt: expireAt,
	}, nil
}

func DeleteSession(dbConn *sql.DB, sessionId string) error {
	_, err := dbConn.Exec(`DELETE FROM user_sessions WHERE id = ?;`, sessionId)
	if err != nil {
		log.Println(err)
		return err
	}

	return nil
}

func RefreshSession(dbConn *sql.DB, sessionId string) (*UserSession, error) {
	newExpireAt := time.Now().Add(ExpiryDuration)

	_, err := dbConn.Exec(`UPDATE user_sessions SET expire_at = ? WHERE id = ?;`, newExpireAt, sessionId)
	if err != nil {
		log.Println(err)
		return nil, err
	}

	session, err := GetSession(dbConn, sessionId)
	if err != nil {
		log.Println(err)
		return nil, err
	}

	return session, nil
}

func DeleteExpiredSessions(dbConn *sql.DB) error {
	_, err := dbConn.Exec(`DELETE FROM user_sessions WHERE expire_at < ?;`, time.Now())
	if err != nil {
		log.Println(err)
		return err
	}
	return nil
}