package file

import (
	"errors"
	"path/filepath"
	"sync"

	"git.andreafazzi.eu/andrea/probo/hasher/sha256"
	"git.andreafazzi.eu/andrea/probo/store/memory"
)

var (
	ErrorMetaHeaderIsNotPresent = errors.New("Meta header was not found in file.")

	DefaultQuizzesDir     = "quizzes"
	DefaultCollectionsDir = "collections"
)

type FileProboCollectorStore struct {
	Dir string

	memoryStore *memory.MemoryProboCollectorStore

	quizzesPaths     map[string]string
	collectionsPaths map[string]string

	quizzesDir     string
	collectionsDir string

	// A mutex is used to synchronize read/write access to the map
	lock sync.RWMutex
}

func NewFileProboCollectorStore(dirname string) (*FileProboCollectorStore, error) {
	s := new(FileProboCollectorStore)

	s.Dir = dirname

	s.quizzesDir = filepath.Join(s.Dir, DefaultQuizzesDir)
	s.collectionsDir = filepath.Join(s.Dir, DefaultCollectionsDir)

	err := s.Reindex()
	if err != nil {
		return nil, err
	}

	return s, nil
}

func (s *FileProboCollectorStore) Reindex() error {
	s.memoryStore = memory.NewMemoryProboCollectorStore(
		sha256.NewDefault256Hasher(sha256.DefaultSHA256HashingFn),
	)

	s.quizzesPaths = make(map[string]string)
	s.collectionsPaths = make(map[string]string)

	err := s.reindexQuizzes()
	if err != nil {
		return err
	}

	err = s.reindexCollections()
	if err != nil {
		return err
	}

	return nil
}