import * as mongoose from 'mongoose'
import { BILL_STATUS, MILAGE_RATES } from './enums'
import { BookingDocument } from './booking'

export interface AdditionalCosts {
  name: string
  value: number
}

export interface BillDocument
  extends mongoose.SchemaTimestampsConfig,
    mongoose.Document {
  booking: BookingDocument
  milageStart: number
  milageEnd: number
  milage?: number
  rate: MILAGE_RATES
  status: BILL_STATUS
  additionalCosts: AdditionalCosts[]
}

export interface BillModel extends mongoose.Model<BillDocument> {}

const BillSchema = new mongoose.Schema<BillDocument>(
  {
    booking: {
      type: mongoose.Schema.Types.ObjectId,
      ref: 'Booking',
      required: true,
    },
    milageStart: { type: Number, required: true },
    milageEnd: { type: Number, required: true },
    rate: {
      type: Number,
      enum: Object.values(MILAGE_RATES),
      default: MILAGE_RATES.EXTERN_UP_TO_200,
      required: true,
    },
    status: {
      type: String,
      enum: Object.values(BILL_STATUS),
      default: BILL_STATUS.UNINVOICED,
      required: true,
    },
    additionalCosts: [
      {
        name: { type: String, required: true },
        value: { type: Number, required: true },
      },
    ],
  },
  { timestamps: true, collation: { locale: 'de', strength: 1 } }
)

BillSchema.virtual('milage').get(function () {
  const bill = this as BillDocument

  if (!bill.milageStart || !bill.milageEnd) {
    return null
  }
  return bill.milageEnd - bill.milageStart
})

BillSchema.virtual('total').get(function () {
  const bill = this as BillDocument

  if (!bill.milageStart || !bill.milageEnd) {
    return null
  }
  const milageCosts = bill.milage * bill.rate
  const additionalCostSum = bill.additionalCosts
    .map(({ value }) => value)
    .reduce((acc, value) => acc + value, 0)

  return milageCosts + additionalCostSum
})

export default <BillModel>mongoose.models.Bill ||
  mongoose.model<BillDocument, BillModel>('Bill', BillSchema)