package comments

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

	"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.Comment, error) {
	comment := models.Comment{}
	err := collection.Find(query).One(&comment)

	return comment, err
}

func list(query interface{}, limit int) ([]models.Comment, error) {
	allocSize := 32
	if limit >= 0 {
		allocSize = limit
	} else {
		limit = 0
	}

	comments := make([]models.Comment, 0, allocSize)
	err := collection.Find(query).Sort("createdDate").Limit(limit).All(&comments)
	if err != nil {
		return nil, err
	}

	return comments, nil
}

func makeCommentID() string {
	result := "SCC"
	offset := 0
	data := make([]byte, 48)

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

		if offset >= 48 {
			rand.Read(data)
			offset = 0
		}
	}

	return result[:32]
}

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

		collection.EnsureIndexKey("chapterId")
		collection.EnsureIndexKey("author")
		collection.EnsureIndexKey("createdDate")
	})
}