package db

import (
	"errors"
	"fmt"
	"io/fs"

	"database/sql"
	"github.com/golang-migrate/migrate/v4"
	"github.com/golang-migrate/migrate/v4/database/pgx/v5"
	sqlitemig "github.com/golang-migrate/migrate/v4/database/sqlite"
	"github.com/golang-migrate/migrate/v4/source/iofs"
	_ "github.com/jackc/pgx/v5/stdlib"
	_ "modernc.org/sqlite"
)

// Migrate applies all up migrations from the given fs (root contains *.sql files).
func Migrate(dsn string, migrations fs.FS) error {
	source, err := iofs.New(migrations, ".")
	if err != nil {
		return fmt.Errorf("migrations source: %w", err)
	}

	sqlDB, err := sql.Open("pgx", dsn)
	if err != nil {
		return fmt.Errorf("open sql db: %w", err)
	}
	defer sqlDB.Close()

	driver, err := pgx.WithInstance(sqlDB, &pgx.Config{})
	if err != nil {
		return fmt.Errorf("migrate driver: %w", err)
	}

	m, err := migrate.NewWithInstance("iofs", source, "pgx", driver)
	if err != nil {
		return fmt.Errorf("migrate instance: %w", err)
	}
	if err := m.Up(); err != nil && !errors.Is(err, migrate.ErrNoChange) {
		return fmt.Errorf("migrate up: %w", err)
	}
	return nil
}

// MigrateSQLite applies all up migrations from the given fs to a SQLite database
// at path (creating it if needed).
func MigrateSQLite(path string, migrations fs.FS) error {
	source, err := iofs.New(migrations, ".")
	if err != nil {
		return fmt.Errorf("migrations source: %w", err)
	}

	sqlDB, err := sql.Open("sqlite", path)
	if err != nil {
		return fmt.Errorf("open sql db: %w", err)
	}
	defer sqlDB.Close()

	driver, err := sqlitemig.WithInstance(sqlDB, &sqlitemig.Config{})
	if err != nil {
		return fmt.Errorf("migrate driver: %w", err)
	}

	m, err := migrate.NewWithInstance("iofs", source, "sqlite", driver)
	if err != nil {
		return fmt.Errorf("migrate instance: %w", err)
	}
	if err := m.Up(); err != nil && !errors.Is(err, migrate.ErrNoChange) {
		return fmt.Errorf("migrate up: %w", err)
	}
	return nil
}