package pg

import (
	"context"
	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgxpool"
	"sync"
)

type Postgres struct {
	db *pgxpool.Pool
}

var (
	pgInstance *Postgres
	pgOnce     sync.Once
)

func NewPgPool(
	ctx context.Context,
	username, password, host, port, dbname string,
) *Postgres {
	connString := "postgres://" + username + ":" + password + "@" + host + ":" + port + "/" + dbname + "?pool_max_conns=100"
	pgOnce.Do(func() {
		db, err := pgxpool.New(ctx, connString)
		if err != nil {
			panic(err)
		}
		pgInstance = &Postgres{db}
	})

	return pgInstance
}

func (pg *Postgres) Insert(ctx context.Context, query string, args ...interface{}) (int64, error) {
	var id int64
	err := pg.db.QueryRow(ctx, query, args...).Scan(&id)
	if err != nil {
		return 0, err
	}
	return id, nil
}

func (pg *Postgres) Select(ctx context.Context, query string, args ...interface{}) (pgx.Rows, error) {
	result, err := pg.db.Query(ctx, query, args...)
	if err != nil {
		return nil, err
	}
	return result, nil
}

func (pg *Postgres) Update(ctx context.Context, query string, args ...interface{}) error {
	_, err := pg.db.Query(ctx, query, args...)
	if err != nil {
		return err
	}
	return nil
}

func (pg *Postgres) Delete(ctx context.Context, query string, args ...interface{}) error {
	_, err := pg.db.Query(ctx, query, args...)
	if err != nil {
		return err
	}
	return nil
}

func (pg *Postgres) CreateTable(ctx context.Context, query string) error {
	_, err := pg.db.Exec(ctx, query)
	if err != nil {
		return err
	}

	return nil
}

func (pg *Postgres) DropTable(ctx context.Context, query string) error {
	_, err := pg.db.Exec(ctx, query)
	if err != nil {
		return err
	}
	return nil
}