TTime/backend/internal/database/db.go

package database

import (
	"embed"
	"log"
	"os"
	"path/filepath"

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

// This struct is a wrapper type that holds the database connection
// Internally DB holds a connection pool, so it's safe for concurrent use
type Db struct {
	*sqlx.DB
}

//go:embed migrations
var scripts embed.FS

const userInsert = "INSERT INTO users (username, password) VALUES (?, ?)"
const projectInsert = "INSERT INTO projects (name, description, user_id) SELECT ?, ?, id FROM users WHERE username = ?"

// DbConnect connects to the database
func DbConnect(dbpath string) *Db {
	// Open the database
	db, err := sqlx.Connect("sqlite3", dbpath)
	if err != nil {
		panic(err)
	}

	// Ping forces the connection to be established
	err = db.Ping()
	if err != nil {
		panic(err)
	}

	return &Db{db}
}

// AddUser adds a user to the database
func (d *Db) AddUser(username string, password string) error {
	_, err := d.Exec(userInsert, username, password)
	return err
}

// Removes a user from the database
func (d *Db) RemoveUser(username string) error {
	_, err := d.Exec("DELETE FROM users WHERE username = ?", username)
	return err
}

func (d *Db) GetUserId(username string) (int, error) {
	var id int
	err := d.Get(&id, "SELECT id FROM users WHERE username = ?", username)
	return id, err
}

// Creates a new project in the database, associated with a user
func (d *Db) AddProject(name string, description string, username string) error {
	_, err := d.Exec(projectInsert, name, description, username)
	return err
}

// Reads a directory of migration files and applies them to the database.
// This will eventually be used on an embedded directory
func (d *Db) Migrate(dirname string) error {
	// Read the embedded scripts directory
	files, err := scripts.ReadDir("migrations")
	if err != nil {
		return err
	}

	tr := d.MustBegin()

	// Iterate over each SQL file and execute it
	for _, file := range files {
		if file.IsDir() || filepath.Ext(file.Name()) != ".sql" {
			continue
		}

		// This is perhaps not the most elegant way to do this
		sqlFile := filepath.Join("migrations", file.Name())
		sqlBytes, err := os.ReadFile(sqlFile)
		if err != nil {
			return err
		}

		sqlQuery := string(sqlBytes)
		_, err = tr.Exec(sqlQuery)
		if err != nil {
			return err
		}
		log.Println("Executed SQL file:", file.Name())
	}

	tr.Commit()
	return nil
}