mark/model.go

package main

import (
	"errors"

	"github.com/br0xen/boltease"
)

// model.go contains some basic database stuff

// MarkDB is an abstraction of a boltease.DB (which is an abstraction of
// a bolt.DB)
type MarkDB struct {
	db             *boltease.DB
	dbOpened       int // Track how many 'open' requests are outstanding
	path, filename string
}

func NewDatabase(path, name string) (*MarkDB, error) {
	if path[len(path)-1] != '/' {
		path = path + "/"
	}
	mdb := MarkDB{
		path:     path,
		filename: name,
	}
	return &mdb, nil
}

func (mdb *MarkDB) openDatabase() error {
	mdb.dbOpened += 1
	if mdb.dbOpened == 1 {
		// We actually need to open the DB
		var err error
		mdb.db, err = boltease.Create(mdb.path+mdb.filename, 0600, nil)
		if err != nil {
			return err
		}
	}
	return nil
}

func (mdb *MarkDB) closeDatabase() error {
	mdb.dbOpened -= 1
	if mdb.dbOpened == 0 {
		// Actually close the database
		return mdb.db.CloseDB()
	}
	return nil
}

func (mdb *MarkDB) initDatabase() error {
	var err error
	if err = mdb.openDatabase(); err != nil {
		return err
	}
	defer mdb.closeDatabase()

	// Create the path to the bucket to store bookmarks
	if err = mdb.db.MkBucketPath([]string{"bookmarks"}); err != nil {
		return errors.New("Error creating 'bookmarks' bucket: " + err.Error())
	}
	// Create the path to the bucket to store additional config
	if err = mdb.db.MkBucketPath([]string{"config"}); err != nil {
		return errors.New("Error creating 'config' bucket: " + err.Error())
	}
	if err = mdb.db.SetInt([]string{"config"}, "lastIdx", 0); err != nil {
		return errors.New("Error setting 'lastIdx' to 0: " + err.Error())
	}
	return nil
}

// GetLastIndex returns the last used index for a bookmark
// If we had a problem getting it, we return the error
func (mdb *MarkDB) GetLastIndex() (int, error) {
	return mdb.db.GetInt([]string{"config"}, "lastIdx")
}

// GetNextIndex returns the next available index for a bookmark
func (mdb *MarkDB) GetNextIndex() int {
	idx, err := mdb.GetLastIndex()
	if err != nil {
		return -1
	}
	return idx + 1
}