package migrate

import (
	"database/sql"
	"fmt"
	"log"
	"os"

	_ "github.com/mattn/go-sqlite3"
)

type Migration struct {
	Version int
	Name    string
}

func Migrate(db *sql.DB) {
	migrationTableSql := `
	CREATE TABLE IF NOT EXISTS migrations(
	  version INTEGER PRIMARY KEY,
	  name VARCHAR(50)
	);`

	_, err := db.Exec(migrationTableSql)
	if err != nil {
		log.Fatal(err)
	}

	files, err := os.ReadDir("./migrations")
	if err != nil {
		log.Fatal("Failed to read migrations directory")
	}

	for _, file := range files {
		fmt.Printf("Checking file: %s\n", file.Name())
		var migration Migration
		row := db.QueryRow("SELECT * FROM migrations WHERE name = ?;", file.Name())
		err = row.Scan(&migration.Version, &migration.Name)
		if err == sql.ErrNoRows {
			fmt.Printf("Running migration: %s\n", file.Name())
			migrationSql, err := os.ReadFile(fmt.Sprintf("./migrations/%s", file.Name()))
			if err != nil {
				log.Fatal(err)
			}

			_, err = db.Exec(string(migrationSql))
			if err != nil {
				log.Fatal(err)
			}

			_, err = db.Exec("INSERT INTO migrations(name) VALUES(?);", file.Name())
			if err != nil {
				log.Fatal(err)
			}
		}
	}
}