package db

import (
	"context"
	"crypto/rand"
	"encoding/hex"
	"time"

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

func (db *DB) CreateSession(ctx context.Context, userID string) (*Session, error) {
	token := make([]byte, 32)
	if _, err := rand.Read(token); err != nil {
		return nil, err
	}

	s := &Session{
		Token:     hex.EncodeToString(token),
		UserID:    userID,
		ExpiresAt: time.Now().Add(30 * 24 * time.Hour),
	}

	_, err := db.pool.Exec(ctx,
		`INSERT INTO sessions (token, user_id, expires_at) VALUES ($1, $2, $3)`,
		s.Token, s.UserID, s.ExpiresAt)
	return s, err
}

func (db *DB) ValidateSession(ctx context.Context, token string) (*Session, error) {
	var s Session
	err := db.pool.QueryRow(ctx,
		`SELECT token, user_id, expires_at FROM sessions
		 WHERE token = $1 AND expires_at > NOW()`,
		token).Scan(&s.Token, &s.UserID, &s.ExpiresAt)
	if err == pgx.ErrNoRows {
		return nil, nil
	}
	return &s, err
}

func (db *DB) DeleteSession(ctx context.Context, token string) error {
	_, err := db.pool.Exec(ctx, `DELETE FROM sessions WHERE token = $1`, token)
	return err
}