package database

import (
	"context"
	"errors"
	"fmt"
	"github.com/jackc/pgx/v4/pgxpool"
	"github.com/knadh/koanf"
	"github.com/rs/zerolog/log"
	"time"
)

func InitPool(config *koanf.Koanf) *pgxpool.Pool {
	pool := NewPool(config)

	if err := runMigrations(pool); err != nil {
		log.Fatal().Err(err).Msg("Couldn't apply migrations")
		panic(err)
	}

	return pool
}

func NewPool(config *koanf.Koanf) *pgxpool.Pool {
	connStr, err := getConnectionString(config)
	if err != nil {
		log.Fatal().Err(err).Msg("Couldn't construct DB connection string")
		panic(err)
	}

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	pool, err := pgxpool.Connect(ctx, connStr)
	if err != nil {
		log.Fatal().Err(err).Msg("Couldn't connect to DB")
		panic(err)
	}

	return pool
}

func getConnectionString(config *koanf.Koanf) (string, error) {
	username := config.String("db.username")
	if username == "" {
		return "", errors.New("database username is missing")
	}

	password := config.String("db.password")
	if password == "" {
		return "", errors.New("database password is missing")
	}

	name := config.String("db.name")
	if name == "" {
		return "", errors.New("database name is missing")
	}

	host := config.String("db.host")
	if name == "" {
		return "", errors.New("database host is missing")
	}

	return fmt.Sprintf("postgresql://%s:%s@%s/%s", username, password, host, name), nil
}