import { Mongoose } from 'mongoose'
import { blockMetaSchema } from './schemas'
import { MongodbUtils } from './utils'

export class BlockMetaDao {
  private model: any

  constructor(mongoose: Mongoose, collectionName: string) {
    this.model = this.getModel(mongoose, collectionName)
  }

  async count(): Promise<number> {
    return await this.model.countDocuments({}).exec()
  }

  async getHighest(): Promise<object | undefined> {
    return await this.model
      .findOne()
      .sort({ height: -1 })
      .exec()
  }

  async getHighestHeight(): Promise<number> {
    // TODO: evaluate placement of business logic in DAO
    try {
      const doc: any = await this.getHighest()
      return doc.height
    } catch (err) {
      return 0
    }
  }

  async save(data: object): Promise<void> {
    return await this.model(data).save()
  }

  async removeByHeight(height: number): Promise<void> {
    return await this.model.deleteMany({ height }).exec()
  }

  async analyze(startHeight: number, endHeight: number): Promise<object[]> {
    /**
     * Example Result:
     * [
     *  { _id: 5bff81ccbbd4fc5d6f3352d5, height: 95, apiLevel: 1 },
     *  { _id: 5bff81ccbbd4fc5d6f3352d9, height: 96, apiLevel: 1 },
     *  ...
     * ]
     */
    return await this.model
      .find(
        {
          height: {
            $gte: startHeight,
            $lte: endHeight,
          },
        },
        'height apiLevel'
      )
      .exec()
  }

  async reviewIndex(key: string, keyObj: object): Promise<void> {
    return await MongodbUtils.reviewIndex(this.model, key, keyObj)
  }

  private getModel(mongoose: Mongoose, collectionName: string) {
    const schema = blockMetaSchema
    return mongoose.models[collectionName] || mongoose.model(collectionName, schema)
  }
}