package files

import (
	"crypto/rand"
	"encoding/binary"
	"strconv"
	"time"

	"git.aiterp.net/rpdata/api/internal/store"
	"git.aiterp.net/rpdata/api/models"
	"github.com/globalsign/mgo"
)

var collection *mgo.Collection

func find(query interface{}) (models.File, error) {
	file := models.File{}

	err := collection.Find(query).One(&file)
	if err != nil {
		return models.File{}, err
	}

	return file, nil
}

func list(query interface{}) ([]models.File, error) {
	list := make([]models.File, 0, 32)

	err := collection.Find(query).Sort("-time").All(&list)
	if err != nil {
		return nil, err
	}

	return list, nil
}

// makeID makes a random file ID that's 32 characters long
func makeID() string {
	result := "F" + strconv.FormatInt(time.Now().UnixNano(), 36)
	offset := 0
	data := make([]byte, 32)

	rand.Read(data)
	for len(result) < 32 {
		result += strconv.FormatUint(binary.LittleEndian.Uint64(data[offset:]), 36)
		offset += 8

		if offset >= 32 {
			rand.Read(data)
			offset = 0
		}
	}

	return result[:32]
}

func init() {
	store.HandleInit(func(db *mgo.Database) {
		collection = db.C("file.headers")

		collection.EnsureIndexKey("author")
		collection.EnsureIndexKey("public")
		collection.EnsureIndexKey("kind", "name", "author")
		collection.EnsureIndexKey("author", "public")
		collection.EnsureIndexKey("kind")
	})
}

var allowdMimeTypes = map[string]bool{
	"":                    false,
	"image/jpeg":          true,
	"image/png":           true,
	"image/gif":           true,
	"text/plain":          true,
	"application/json":    true,
	"application/pdf":     false,
	"binary/octet-stream": false,
	"video/mp4":           false,
	"audio/mp3":           false,
}