package unknownnicks

import (
	"sync"

	"github.com/globalsign/mgo/bson"
)

var updateMutex sync.Mutex
var updateMap map[string]int

// Add adds a nick as unknown.
func Add(nick string) {
	updateMap[nick] = updateMap[nick] + 1
}

// BeginUpdate starts an add operation
func BeginUpdate() error {
	updateMutex.Lock()

	_, err := collection.RemoveAll(bson.M{})
	if err != nil {
		updateMutex.Unlock()
		return err
	}

	if updateMap == nil {
		updateMap = make(map[string]int)
	}

	for key := range updateMap {
		delete(updateMap, key)
	}

	return nil
}

// CancelUpdate cancels an add operation
func CancelUpdate() {
	updateMutex.Unlock()
}

// CommitUpdate commits an add operation to the database.
func CommitUpdate() error {
	defer updateMutex.Unlock()

	for nick, score := range updateMap {
		_, err := collection.UpsertId(nick, bson.M{"$set": bson.M{"score": score}})
		if err != nil {
			return err
		}
	}

	return nil
}