package postgres

import (
	"context"
	"fmt"
	"time"

	"git.optclblast.xyz/draincloud/draincloud-light/internal/closer"
	"git.optclblast.xyz/draincloud/draincloud-light/internal/logger"
	"git.optclblast.xyz/draincloud/draincloud-light/internal/storage/models"
	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgconn"
)

type Database struct {
	db *pgx.Conn
}

func New(ctx context.Context, dsn string) *Database {
	db, err := pgx.Connect(ctx, dsn)
	if err != nil {
		logger.Fatal(ctx, "failed to connect to postgres", logger.Err(err))
	}

	closer.Add(func() error {
		ctx, cancel := context.WithTimeout(ctx, 2*time.Second)
		defer cancel()
		return db.Close(ctx)
	})

	return &Database{db: db}
}

type dbtx interface {
	Exec(ctx context.Context, stmt string, args ...any) (pgconn.CommandTag, error)
	QueryRow(ctx context.Context, sql string, args ...any) pgx.Row
	Query(ctx context.Context, sql string, args ...any) (pgx.Rows, error)
}

func (d *Database) AddUser(ctx context.Context, login string, username string, passwordHash []byte) (uint64, error) {
	return addUser(ctx, d.db, login, username, passwordHash)
}

func (d *Database) GetUserByID(ctx context.Context, id uint64) (*models.User, error) {
	return getUserByID(ctx, d.db, id)
}

func (d *Database) GetUserByLogin(ctx context.Context, login string) (*models.User, error) {
	return getUserByLogin(ctx, d.db, login)
}

func addUser(ctx context.Context, conn dbtx, login string, username string, passwordHash []byte) (uint64, error) {
	const stmt = `INSERT INTO users (login,username,password)
		VALUES ($1,$2,$3,$4) RETURNING id`

	row := conn.QueryRow(ctx, stmt, login, username, passwordHash)

	var id uint64

	if err := row.Scan(&id); err != nil {
		return 0, fmt.Errorf("failed to insert user data into users table: %w", err)
	}

	return id, nil
}

func getUserByID(ctx context.Context, conn dbtx, id uint64) (*models.User, error) {
	const stmt = `SELECT * FROM users WHERE id = $1 LIMIT 1`
	u := new(models.User)

	row := conn.QueryRow(ctx, stmt, id)
	if err := row.Scan(&u.ID, &u.Login, &u.Username, &u.PasswordHash, &u.CreatedAt, &u.UpdatedAt); err != nil {
		return nil, fmt.Errorf("failed to fetch user by id: %w", err)
	}

	return u, nil
}

func getUserByLogin(ctx context.Context, conn dbtx, login string) (*models.User, error) {
	const stmt = `SELECT * FROM users WHERE login = $1 LIMIT 1`
	u := new(models.User)

	row := conn.QueryRow(ctx, stmt, login)
	if err := row.Scan(&u.ID, &u.Login, &u.Username, &u.PasswordHash, &u.CreatedAt, &u.UpdatedAt); err != nil {
		return nil, fmt.Errorf("failed to fetch user by login: %w", err)
	}

	return u, nil
}