// Package postgres provides GL's PostgreSQL adapters.
package postgres

import (
	"context"
	"fmt"
	"net/url"
	"strconv"

	"gl/infrastructure/config"

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

type Row interface {
	Scan(dest ...any) error
}

type Tx interface {
	Exec(context.Context, string, ...any) (pgconn.CommandTag, error)
	QueryRow(context.Context, string, ...any) Row
	Commit(context.Context) error
	Rollback(context.Context) error
}

type Database interface {
	Begin(context.Context) (Tx, error)
	QueryRow(context.Context, string, ...any) Row
	Ping(context.Context) error
	Close()
}

type Pool struct {
	pool *pgxpool.Pool
}

func Open(ctx context.Context, cfg config.DatabaseConfig) (*Pool, error) {
	connectionURL := &url.URL{
		Scheme: "postgres",
		User:   url.UserPassword(cfg.User, cfg.Password),
		Host:   cfg.Host + ":" + strconv.Itoa(cfg.Port),
		Path:   cfg.Name,
	}
	query := connectionURL.Query()
	query.Set("sslmode", cfg.SSLMode)
	connectionURL.RawQuery = query.Encode()

	pool, err := pgxpool.New(ctx, connectionURL.String())
	if err != nil {
		return nil, fmt.Errorf("create postgres pool: %w", err)
	}
	return &Pool{pool: pool}, nil
}

func (p *Pool) Begin(ctx context.Context) (Tx, error) {
	tx, err := p.pool.BeginTx(ctx, pgx.TxOptions{})
	if err != nil {
		return nil, err
	}
	return txAdapter{Tx: tx}, nil
}

func (p *Pool) Ping(ctx context.Context) error {
	return p.pool.Ping(ctx)
}

func (p *Pool) QueryRow(ctx context.Context, sql string, args ...any) Row {
	return p.pool.QueryRow(ctx, sql, args...)
}

func (p *Pool) Close() {
	p.pool.Close()
}

type txAdapter struct {
	pgx.Tx
}

func (t txAdapter) QueryRow(ctx context.Context, sql string, args ...any) Row {
	return t.Tx.QueryRow(ctx, sql, args...)
}