project-inter-server/src/repositories/parking/RedisParkingRepository.ts

import { ParkingGetterSetterRepository } from "./ParkingGetterSetterRepository";
import { IParkingStructure } from "../../entities/ParkingRepositoryEntities";
import { HistoricalParkingAverageQueryResult, ParkingStructureCountOptions } from "./ParkingGetterRepository";
import { BaseRedisRepository } from "../BaseRedisRepository";
import { PARKING_LOGGING_INTERVAL_MS } from "./ParkingRepositoryConstants";

export type ParkingStructureID = string;

export class RedisParkingRepository extends BaseRedisRepository implements ParkingGetterSetterRepository {
  private dataLastAdded: Map<ParkingStructureID, Date> = new Map();
  private loggingIntervalMs = PARKING_LOGGING_INTERVAL_MS;

  addOrUpdateParkingStructure = async (structure: IParkingStructure): Promise<void> => {
    const keys = this.createRedisKeys(structure.id);
    await this.redisClient.hSet(keys.structure, this.createRedisHashFromStructure(structure));
    await this.addHistoricalDataForStructure(structure);
  };

  private addHistoricalDataForStructure = async (structure: IParkingStructure): Promise<void> => {
    const now = Date.now();
    const lastAdded = this.dataLastAdded.get(structure.id);

    if (this.shouldLogHistoricalData(lastAdded, now)) {
      const keys = this.createRedisKeys(structure.id);
      await this.addTimeSeriesDataPoint(keys.timeSeries, now, structure.spotsAvailable, structure.id);
      this.dataLastAdded.set(structure.id, new Date(now));
    }
  };

  clearParkingStructureData = async (): Promise<void> => {
    const structureKeys = await this.redisClient.keys('parking:structure:*');
    const timeSeriesKeys = await this.redisClient.keys('parking:timeseries:*');

    const allKeys = [...structureKeys, ...timeSeriesKeys];
    if (allKeys.length > 0) {
      await this.redisClient.del(allKeys);
    }

    this.dataLastAdded.clear();
  };

  getParkingStructureById = async (id: string): Promise<IParkingStructure | null> => {
    const keys = this.createRedisKeys(id);
    const data = await this.redisClient.hGetAll(keys.structure);

    if (Object.keys(data).length === 0) {
      return null;
    }

    return this.createStructureFromRedisData(data);
  };

  getParkingStructures = async (): Promise<IParkingStructure[]> => {
    const keys = await this.redisClient.keys('parking:structure:*');
    const structures: IParkingStructure[] = [];

    for (const key of keys) {
      const data = await this.redisClient.hGetAll(key);
      if (Object.keys(data).length > 0) {
        structures.push(this.createStructureFromRedisData(data));
      }
    }

    return structures;
  };

  removeParkingStructureIfExists = async (id: string): Promise<IParkingStructure | null> => {
    const structure = await this.getParkingStructureById(id);
    if (structure) {
      const keys = this.createRedisKeys(id);
      await this.redisClient.del([keys.structure, keys.timeSeries]);
      this.dataLastAdded.delete(id);
      return structure;
    }
    return null;
  };

  getHistoricalAveragesOfParkingStructureCounts = async (id: string, options: ParkingStructureCountOptions): Promise<HistoricalParkingAverageQueryResult[]> => {
    return this.calculateAveragesFromRecords(id, options);
  };

  private createRedisKeys = (structureId: string) => ({
    structure: `parking:structure:${structureId}`,
    timeSeries: `parking:timeseries:${structureId}`
  });

  private createRedisHashFromStructure = (structure: IParkingStructure): Record<string, string> => ({
    id: structure.id,
    name: structure.name,
    address: structure.address,
    capacity: structure.capacity.toString(),
    spotsAvailable: structure.spotsAvailable.toString(),
    latitude: structure.coordinates.latitude.toString(),
    longitude: structure.coordinates.longitude.toString(),
    updatedTime: structure.updatedTime.toISOString()
  });

  private createStructureFromRedisData = (data: Record<string, string>): IParkingStructure => ({
    id: data.id,
    name: data.name,
    address: data.address,
    capacity: parseInt(data.capacity),
    spotsAvailable: parseInt(data.spotsAvailable),
    coordinates: {
      latitude: parseFloat(data.latitude),
      longitude: parseFloat(data.longitude)
    },
    updatedTime: new Date(data.updatedTime)
  });

  private shouldLogHistoricalData = (lastAdded: Date | undefined, currentTime: number): boolean => {
    return !lastAdded || (currentTime - lastAdded.getTime()) >= this.loggingIntervalMs;
  };

  private addTimeSeriesDataPoint = async (timeSeriesKey: string, timestamp: number, value: number, structureId: string): Promise<void> => {
    try {
      await this.redisClient.sendCommand([
        'TS.ADD',
        timeSeriesKey,
        timestamp.toString(),
        value.toString(),
        'LABELS',
        'structureId',
        structureId
      ]);
    } catch (error) {
      await this.createTimeSeriesAndAddDataPoint(timeSeriesKey, timestamp, value, structureId);
    }
  };

  private createTimeSeriesAndAddDataPoint = async (timeSeriesKey: string, timestamp: number, value: number, structureId: string): Promise<void> => {
    try {
      await this.redisClient.sendCommand([
        'TS.CREATE',
        timeSeriesKey,
        'RETENTION',
        '2678400000',  // one month
        'LABELS',
        'structureId',
        structureId
      ]);
      await this.redisClient.sendCommand([
        'TS.ADD',
        timeSeriesKey,
        timestamp.toString(),
        value.toString()
      ]);
    } catch (createError) {
      await this.redisClient.sendCommand([
        'TS.ADD',
        timeSeriesKey,
        timestamp.toString(),
        value.toString()
      ]);
    }
  };

  private calculateAveragesFromRecords = async (
    id: string,
    options: ParkingStructureCountOptions
  ): Promise<HistoricalParkingAverageQueryResult[]> => {
    const keys = this.createRedisKeys(id);
    const { from, to, intervalMs } = options;
    const results: HistoricalParkingAverageQueryResult[] = [];

    let currentIntervalStart = from.getTime();
    const endTime = to.getTime();

    while (currentIntervalStart < endTime) {
      const currentIntervalEnd = Math.min(currentIntervalStart + intervalMs, endTime);

      try {
        const aggregationResult = await this.redisClient.sendCommand([
          'TS.RANGE',
          keys.timeSeries,
          currentIntervalStart.toString(),
          currentIntervalEnd.toString(),
          'AGGREGATION',
          'AVG',
          intervalMs.toString()
        ]) as [string, string][];

        if (aggregationResult && aggregationResult.length > 0) {
          const [, averageValue] = aggregationResult[0];
          results.push({
            from: new Date(currentIntervalStart),
            to: new Date(currentIntervalEnd),
            averageSpotsAvailable: parseFloat(averageValue)
          });
        }
      } catch (error) {
        // If Redis aggregation fails, skip this interval
      }

      currentIntervalStart = currentIntervalEnd;
    }

    return results;
  };

  setLoggingInterval = (intervalMs: number): void => {
    this.loggingIntervalMs = intervalMs;
  };
}